Merge commit 'v3.15' into next

139 files changed, 7435 insertions, 5648 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index bc010ee272b6..f2a8b6246ce9 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -18,11 +18,13 @@ CFLAGS_REMOVE_cgroup-debug.o = -pg
 CFLAGS_REMOVE_irq_work.o = -pg
 endif
 
+# cond_syscall is currently not LTO compatible
+CFLAGS_sys_ni.o = $(DISABLE_LTO)
+
 obj-y += sched/
 obj-y += locking/
 obj-y += power/
 obj-y += printk/
-obj-y += cpu/
 obj-y += irq/
 obj-y += rcu/
 
@@ -93,6 +95,7 @@ obj-$(CONFIG_PADATA) += padata.o
 obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
 obj-$(CONFIG_JUMP_LABEL) += jump_label.o
 obj-$(CONFIG_CONTEXT_TRACKING) += context_tracking.o
+obj-$(CONFIG_TORTURE_TEST) += torture.o
 
 $(obj)/configs.o: $(obj)/config_data.h
 
diff --git a/kernel/audit.c b/kernel/audit.c
index 95a20f3f52f1..47845c57eb19 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -182,7 +182,7 @@ struct audit_buffer {
 
 struct audit_reply {
 	__u32 portid;
-	struct net *net;	
+	struct net *net;
 	struct sk_buff *skb;
 };
 
@@ -396,7 +396,7 @@ static void audit_printk_skb(struct sk_buff *skb)
 		if (printk_ratelimit())
 			pr_notice("type=%d %s\n", nlh->nlmsg_type, data);
 		else
-			audit_log_lost("printk limit exceeded\n");
+			audit_log_lost("printk limit exceeded");
 	}
 
 	audit_hold_skb(skb);
@@ -412,7 +412,7 @@ static void kauditd_send_skb(struct sk_buff *skb)
 		BUG_ON(err != -ECONNREFUSED); /* Shouldn't happen */
 		if (audit_pid) {
 			pr_err("*NO* daemon at audit_pid=%d\n", audit_pid);
-			audit_log_lost("auditd disappeared\n");
+			audit_log_lost("auditd disappeared");
 			audit_pid = 0;
 			audit_sock = NULL;
 		}
@@ -607,7 +607,7 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
 {
 	int err = 0;
 
-	/* Only support the initial namespaces for now. */
+	/* Only support initial user namespace for now. */
 	/*
 	 * We return ECONNREFUSED because it tricks userspace into thinking
 	 * that audit was not configured into the kernel.  Lots of users
@@ -618,8 +618,7 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
 	 * userspace will reject all logins.  This should be removed when we
 	 * support non init namespaces!!
 	 */
-	if ((current_user_ns() != &init_user_ns) ||
-	    (task_active_pid_ns(current) != &init_pid_ns))
+	if (current_user_ns() != &init_user_ns)
 		return -ECONNREFUSED;
 
 	switch (msg_type) {
@@ -639,13 +638,18 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
 	case AUDIT_TTY_SET:
 	case AUDIT_TRIM:
 	case AUDIT_MAKE_EQUIV:
-		if (!capable(CAP_AUDIT_CONTROL))
+		/* Only support auditd and auditctl in initial pid namespace
+		 * for now. */
+		if ((task_active_pid_ns(current) != &init_pid_ns))
+			return -EPERM;
+
+		if (!netlink_capable(skb, CAP_AUDIT_CONTROL))
 			err = -EPERM;
 		break;
 	case AUDIT_USER:
 	case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
 	case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
-		if (!capable(CAP_AUDIT_WRITE))
+		if (!netlink_capable(skb, CAP_AUDIT_WRITE))
 			err = -EPERM;
 		break;
 	default:  /* bad msg */
@@ -659,6 +663,7 @@ static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type)
 {
 	int rc = 0;
 	uid_t uid = from_kuid(&init_user_ns, current_uid());
+	pid_t pid = task_tgid_nr(current);
 
 	if (!audit_enabled && msg_type != AUDIT_USER_AVC) {
 		*ab = NULL;
@@ -668,7 +673,7 @@ static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type)
 	*ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
 	if (unlikely(!*ab))
 		return rc;
-	audit_log_format(*ab, "pid=%d uid=%u", task_tgid_vnr(current), uid);
+	audit_log_format(*ab, "pid=%d uid=%u", pid, uid);
 	audit_log_session_info(*ab);
 	audit_log_task_context(*ab);
 
@@ -1097,7 +1102,7 @@ static void __net_exit audit_net_exit(struct net *net)
 		audit_sock = NULL;
 	}
 
-	rcu_assign_pointer(aunet->nlsk, NULL);
+	RCU_INIT_POINTER(aunet->nlsk, NULL);
 	synchronize_net();
 	netlink_kernel_release(sock);
 }
@@ -1829,11 +1834,11 @@ void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
 	spin_unlock_irq(&tsk->sighand->siglock);
 
 	audit_log_format(ab,
-			 " ppid=%ld pid=%d auid=%u uid=%u gid=%u"
+			 " ppid=%d pid=%d auid=%u uid=%u gid=%u"
 			 " euid=%u suid=%u fsuid=%u"
 			 " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
-			 sys_getppid(),
-			 tsk->pid,
+			 task_ppid_nr(tsk),
+			 task_pid_nr(tsk),
 			 from_kuid(&init_user_ns, audit_get_loginuid(tsk)),
 			 from_kuid(&init_user_ns, cred->uid),
 			 from_kgid(&init_user_ns, cred->gid),
diff --git a/kernel/audit.h b/kernel/audit.h
index 8df132214606..7bb65730c890 100644
--- a/kernel/audit.h
+++ b/kernel/audit.h
@@ -106,6 +106,11 @@ struct audit_names {
 	bool			should_free;
 };
 
+struct audit_proctitle {
+	int	len;	/* length of the cmdline field. */
+	char	*value;	/* the cmdline field */
+};
+
 /* The per-task audit context. */
 struct audit_context {
 	int		    dummy;	/* must be the first element */
@@ -202,6 +207,7 @@ struct audit_context {
 		} execve;
 	};
 	int fds[2];
+	struct audit_proctitle proctitle;
 
 #if AUDIT_DEBUG
 	int		    put_count;
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index 92062fd6cc8c..8e9bc9c3dbb7 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -19,6 +19,8 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/kernel.h>
 #include <linux/audit.h>
 #include <linux/kthread.h>
@@ -226,7 +228,7 @@ static int audit_match_signal(struct audit_entry *entry)
 #endif
 
 /* Common user-space to kernel rule translation. */
-static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule)
+static inline struct audit_entry *audit_to_entry_common(struct audit_rule_data *rule)
 {
 	unsigned listnr;
 	struct audit_entry *entry;
@@ -249,7 +251,7 @@ static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule)
 		;
 	}
 	if (unlikely(rule->action == AUDIT_POSSIBLE)) {
-		printk(KERN_ERR "AUDIT_POSSIBLE is deprecated\n");
+		pr_err("AUDIT_POSSIBLE is deprecated\n");
 		goto exit_err;
 	}
 	if (rule->action != AUDIT_NEVER && rule->action != AUDIT_ALWAYS)
@@ -403,7 +405,7 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
 	int i;
 	char *str;
 
-	entry = audit_to_entry_common((struct audit_rule *)data);
+	entry = audit_to_entry_common(data);
 	if (IS_ERR(entry))
 		goto exit_nofree;
 
@@ -431,6 +433,19 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
 			f->val = 0;
 		}
 
+		if ((f->type == AUDIT_PID) || (f->type == AUDIT_PPID)) {
+			struct pid *pid;
+			rcu_read_lock();
+			pid = find_vpid(f->val);
+			if (!pid) {
+				rcu_read_unlock();
+				err = -ESRCH;
+				goto exit_free;
+			}
+			f->val = pid_nr(pid);
+			rcu_read_unlock();
+		}
+
 		err = audit_field_valid(entry, f);
 		if (err)
 			goto exit_free;
@@ -479,8 +494,8 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
 			/* Keep currently invalid fields around in case they
 			 * become valid after a policy reload. */
 			if (err == -EINVAL) {
-				printk(KERN_WARNING "audit rule for LSM "
-				       "\'%s\' is invalid\n",  str);
+				pr_warn("audit rule for LSM \'%s\' is invalid\n",
+					str);
 				err = 0;
 			}
 			if (err) {
@@ -709,8 +724,8 @@ static inline int audit_dupe_lsm_field(struct audit_field *df,
 	/* Keep currently invalid fields around in case they
 	 * become valid after a policy reload. */
 	if (ret == -EINVAL) {
-		printk(KERN_WARNING "audit rule for LSM \'%s\' is "
-		       "invalid\n", df->lsm_str);
+		pr_warn("audit rule for LSM \'%s\' is invalid\n",
+			df->lsm_str);
 		ret = 0;
 	}
 
@@ -1240,12 +1255,14 @@ static int audit_filter_user_rules(struct audit_krule *rule, int type,
 
 	for (i = 0; i < rule->field_count; i++) {
 		struct audit_field *f = &rule->fields[i];
+		pid_t pid;
 		int result = 0;
 		u32 sid;
 
 		switch (f->type) {
 		case AUDIT_PID:
-			result = audit_comparator(task_pid_vnr(current), f->op, f->val);
+			pid = task_pid_nr(current);
+			result = audit_comparator(pid, f->op, f->val);
 			break;
 		case AUDIT_UID:
 			result = audit_uid_comparator(current_uid(), f->op, f->uid);
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 7aef2f4b6c64..f251a5e8d17a 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -42,6 +42,8 @@
  * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance.
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/init.h>
 #include <asm/types.h>
 #include <linux/atomic.h>
@@ -68,6 +70,7 @@
 #include <linux/capability.h>
 #include <linux/fs_struct.h>
 #include <linux/compat.h>
+#include <linux/ctype.h>
 
 #include "audit.h"
 
@@ -79,6 +82,9 @@
 /* no execve audit message should be longer than this (userspace limits) */
 #define MAX_EXECVE_AUDIT_LEN 7500
 
+/* max length to print of cmdline/proctitle value during audit */
+#define MAX_PROCTITLE_AUDIT_LEN 128
+
 /* number of audit rules */
 int audit_n_rules;
 
@@ -451,15 +457,17 @@ static int audit_filter_rules(struct task_struct *tsk,
 		struct audit_field *f = &rule->fields[i];
 		struct audit_names *n;
 		int result = 0;
+		pid_t pid;
 
 		switch (f->type) {
 		case AUDIT_PID:
-			result = audit_comparator(tsk->pid, f->op, f->val);
+			pid = task_pid_nr(tsk);
+			result = audit_comparator(pid, f->op, f->val);
 			break;
 		case AUDIT_PPID:
 			if (ctx) {
 				if (!ctx->ppid)
-					ctx->ppid = sys_getppid();
+					ctx->ppid = task_ppid_nr(tsk);
 				result = audit_comparator(ctx->ppid, f->op, f->val);
 			}
 			break;
@@ -805,7 +813,8 @@ void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
 	rcu_read_unlock();
 }
 
-static inline struct audit_context *audit_get_context(struct task_struct *tsk,
+/* Transfer the audit context pointer to the caller, clearing it in the tsk's struct */
+static inline struct audit_context *audit_take_context(struct task_struct *tsk,
 						      int return_valid,
 						      long return_code)
 {
@@ -842,6 +851,13 @@ static inline struct audit_context *audit_get_context(struct task_struct *tsk,
 	return context;
 }
 
+static inline void audit_proctitle_free(struct audit_context *context)
+{
+	kfree(context->proctitle.value);
+	context->proctitle.value = NULL;
+	context->proctitle.len = 0;
+}
+
 static inline void audit_free_names(struct audit_context *context)
 {
 	struct audit_names *n, *next;
@@ -850,16 +866,15 @@ static inline void audit_free_names(struct audit_context *context)
 	if (context->put_count + context->ino_count != context->name_count) {
 		int i = 0;
 
-		printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
-		       " name_count=%d put_count=%d"
-		       " ino_count=%d [NOT freeing]\n",
-		       __FILE__, __LINE__,
+		pr_err("%s:%d(:%d): major=%d in_syscall=%d"
+		       " name_count=%d put_count=%d ino_count=%d"
+		       " [NOT freeing]\n", __FILE__, __LINE__,
 		       context->serial, context->major, context->in_syscall,
 		       context->name_count, context->put_count,
 		       context->ino_count);
 		list_for_each_entry(n, &context->names_list, list) {
-			printk(KERN_ERR "names[%d] = %p = %s\n", i++,
-			       n->name, n->name->name ?: "(null)");
+			pr_err("names[%d] = %p = %s\n", i++, n->name,
+			       n->name->name ?: "(null)");
 		}
 		dump_stack();
 		return;
@@ -955,6 +970,7 @@ static inline void audit_free_context(struct audit_context *context)
 	audit_free_aux(context);
 	kfree(context->filterkey);
 	kfree(context->sockaddr);
+	audit_proctitle_free(context);
 	kfree(context);
 }
 
@@ -1157,7 +1173,7 @@ static void audit_log_execve_info(struct audit_context *context,
 	 */
 	buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
 	if (!buf) {
-		audit_panic("out of memory for argv string\n");
+		audit_panic("out of memory for argv string");
 		return;
 	}
 
@@ -1271,6 +1287,59 @@ static void show_special(struct audit_context *context, int *call_panic)
 	audit_log_end(ab);
 }
 
+static inline int audit_proctitle_rtrim(char *proctitle, int len)
+{
+	char *end = proctitle + len - 1;
+	while (end > proctitle && !isprint(*end))
+		end--;
+
+	/* catch the case where proctitle is only 1 non-print character */
+	len = end - proctitle + 1;
+	len -= isprint(proctitle[len-1]) == 0;
+	return len;
+}
+
+static void audit_log_proctitle(struct task_struct *tsk,
+			 struct audit_context *context)
+{
+	int res;
+	char *buf;
+	char *msg = "(null)";
+	int len = strlen(msg);
+	struct audit_buffer *ab;
+
+	ab = audit_log_start(context, GFP_KERNEL, AUDIT_PROCTITLE);
+	if (!ab)
+		return;	/* audit_panic or being filtered */
+
+	audit_log_format(ab, "proctitle=");
+
+	/* Not  cached */
+	if (!context->proctitle.value) {
+		buf = kmalloc(MAX_PROCTITLE_AUDIT_LEN, GFP_KERNEL);
+		if (!buf)
+			goto out;
+		/* Historically called this from procfs naming */
+		res = get_cmdline(tsk, buf, MAX_PROCTITLE_AUDIT_LEN);
+		if (res == 0) {
+			kfree(buf);
+			goto out;
+		}
+		res = audit_proctitle_rtrim(buf, res);
+		if (res == 0) {
+			kfree(buf);
+			goto out;
+		}
+		context->proctitle.value = buf;
+		context->proctitle.len = res;
+	}
+	msg = context->proctitle.value;
+	len = context->proctitle.len;
+out:
+	audit_log_n_untrustedstring(ab, msg, len);
+	audit_log_end(ab);
+}
+
 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
 {
 	int i, call_panic = 0;
@@ -1388,6 +1457,8 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
 		audit_log_name(context, n, NULL, i++, &call_panic);
 	}
 
+	audit_log_proctitle(tsk, context);
+
 	/* Send end of event record to help user space know we are finished */
 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
 	if (ab)
@@ -1406,7 +1477,7 @@ void __audit_free(struct task_struct *tsk)
 {
 	struct audit_context *context;
 
-	context = audit_get_context(tsk, 0, 0);
+	context = audit_take_context(tsk, 0, 0);
 	if (!context)
 		return;
 
@@ -1500,7 +1571,7 @@ void __audit_syscall_exit(int success, long return_code)
 	else
 		success = AUDITSC_FAILURE;
 
-	context = audit_get_context(tsk, success, return_code);
+	context = audit_take_context(tsk, success, return_code);
 	if (!context)
 		return;
 
@@ -1550,7 +1621,7 @@ static inline void handle_one(const struct inode *inode)
 	if (likely(put_tree_ref(context, chunk)))
 		return;
 	if (unlikely(!grow_tree_refs(context))) {
-		printk(KERN_WARNING "out of memory, audit has lost a tree reference\n");
+		pr_warn("out of memory, audit has lost a tree reference\n");
 		audit_set_auditable(context);
 		audit_put_chunk(chunk);
 		unroll_tree_refs(context, p, count);
@@ -1609,8 +1680,7 @@ retry:
 			goto retry;
 		}
 		/* too bad */
-		printk(KERN_WARNING
-			"out of memory, audit has lost a tree reference\n");
+		pr_warn("out of memory, audit has lost a tree reference\n");
 		unroll_tree_refs(context, p, count);
 		audit_set_auditable(context);
 		return;
@@ -1682,7 +1752,7 @@ void __audit_getname(struct filename *name)
 
 	if (!context->in_syscall) {
 #if AUDIT_DEBUG == 2
-		printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n",
+		pr_err("%s:%d(:%d): ignoring getname(%p)\n",
 		       __FILE__, __LINE__, context->serial, name);
 		dump_stack();
 #endif
@@ -1721,15 +1791,15 @@ void audit_putname(struct filename *name)
 	BUG_ON(!context);
 	if (!name->aname || !context->in_syscall) {
 #if AUDIT_DEBUG == 2
-		printk(KERN_ERR "%s:%d(:%d): final_putname(%p)\n",
+		pr_err("%s:%d(:%d): final_putname(%p)\n",
 		       __FILE__, __LINE__, context->serial, name);
 		if (context->name_count) {
 			struct audit_names *n;
 			int i = 0;
 
 			list_for_each_entry(n, &context->names_list, list)
-				printk(KERN_ERR "name[%d] = %p = %s\n", i++,
-				       n->name, n->name->name ?: "(null)");
+				pr_err("name[%d] = %p = %s\n", i++, n->name,
+				       n->name->name ?: "(null)");
 			}
 #endif
 		final_putname(name);
@@ -1738,9 +1808,8 @@ void audit_putname(struct filename *name)
 	else {
 		++context->put_count;
 		if (context->put_count > context->name_count) {
-			printk(KERN_ERR "%s:%d(:%d): major=%d"
-			       " in_syscall=%d putname(%p) name_count=%d"
-			       " put_count=%d\n",
+			pr_err("%s:%d(:%d): major=%d in_syscall=%d putname(%p)"
+			       " name_count=%d put_count=%d\n",
 			       __FILE__, __LINE__,
 			       context->serial, context->major,
 			       context->in_syscall, name->name,
@@ -1981,12 +2050,10 @@ static void audit_log_set_loginuid(kuid_t koldloginuid, kuid_t kloginuid,
 	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
 	if (!ab)
 		return;
-	audit_log_format(ab, "pid=%d uid=%u"
-			 " old-auid=%u new-auid=%u old-ses=%u new-ses=%u"
-			 " res=%d",
-			 current->pid, uid,
-			 oldloginuid, loginuid, oldsessionid, sessionid,
-			 !rc);
+	audit_log_format(ab, "pid=%d uid=%u", task_pid_nr(current), uid);
+	audit_log_task_context(ab);
+	audit_log_format(ab, " old-auid=%u auid=%u old-ses=%u ses=%u res=%d",
+			 oldloginuid, loginuid, oldsessionid, sessionid, !rc);
 	audit_log_end(ab);
 }
 
@@ -2208,7 +2275,7 @@ void __audit_ptrace(struct task_struct *t)
 {
 	struct audit_context *context = current->audit_context;
 
-	context->target_pid = t->pid;
+	context->target_pid = task_pid_nr(t);
 	context->target_auid = audit_get_loginuid(t);
 	context->target_uid = task_uid(t);
 	context->target_sessionid = audit_get_sessionid(t);
@@ -2233,7 +2300,7 @@ int __audit_signal_info(int sig, struct task_struct *t)
 
 	if (audit_pid && t->tgid == audit_pid) {
 		if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) {
-			audit_sig_pid = tsk->pid;
+			audit_sig_pid = task_pid_nr(tsk);
 			if (uid_valid(tsk->loginuid))
 				audit_sig_uid = tsk->loginuid;
 			else
@@ -2247,7 +2314,7 @@ int __audit_signal_info(int sig, struct task_struct *t)
 	/* optimize the common case by putting first signal recipient directly
 	 * in audit_context */
 	if (!ctx->target_pid) {
-		ctx->target_pid = t->tgid;
+		ctx->target_pid = task_tgid_nr(t);
 		ctx->target_auid = audit_get_loginuid(t);
 		ctx->target_uid = t_uid;
 		ctx->target_sessionid = audit_get_sessionid(t);
@@ -2268,7 +2335,7 @@ int __audit_signal_info(int sig, struct task_struct *t)
 	}
 	BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
 
-	axp->target_pid[axp->pid_count] = t->tgid;
+	axp->target_pid[axp->pid_count] = task_tgid_nr(t);
 	axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
 	axp->target_uid[axp->pid_count] = t_uid;
 	axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
@@ -2368,7 +2435,7 @@ static void audit_log_task(struct audit_buffer *ab)
 			 from_kgid(&init_user_ns, gid),
 			 sessionid);
 	audit_log_task_context(ab);
-	audit_log_format(ab, " pid=%d comm=", current->pid);
+	audit_log_format(ab, " pid=%d comm=", task_pid_nr(current));
 	audit_log_untrustedstring(ab, current->comm);
 	if (mm) {
 		down_read(&mm->mmap_sem);
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 0c753ddd223b..ceee0c54c6a4 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -33,6 +33,7 @@
 #include <linux/init_task.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
+#include <linux/magic.h>
 #include <linux/mm.h>
 #include <linux/mutex.h>
 #include <linux/mount.h>
@@ -40,23 +41,20 @@
 #include <linux/proc_fs.h>
 #include <linux/rcupdate.h>
 #include <linux/sched.h>
-#include <linux/backing-dev.h>
 #include <linux/slab.h>
-#include <linux/magic.h>
 #include <linux/spinlock.h>
+#include <linux/rwsem.h>
 #include <linux/string.h>
 #include <linux/sort.h>
 #include <linux/kmod.h>
-#include <linux/module.h>
 #include <linux/delayacct.h>
 #include <linux/cgroupstats.h>
 #include <linux/hashtable.h>
-#include <linux/namei.h>
 #include <linux/pid_namespace.h>
 #include <linux/idr.h>
 #include <linux/vmalloc.h> /* TODO: replace with more sophisticated array */
-#include <linux/flex_array.h> /* used in cgroup_attach_task */
 #include <linux/kthread.h>
+#include <linux/delay.h>
 
 #include <linux/atomic.h>
 
@@ -68,43 +66,49 @@
  */
 #define CGROUP_PIDLIST_DESTROY_DELAY	HZ
 
+#define CGROUP_FILE_NAME_MAX		(MAX_CGROUP_TYPE_NAMELEN +	\
+					 MAX_CFTYPE_NAME + 2)
+
+/*
+ * cgroup_tree_mutex nests above cgroup_mutex and protects cftypes, file
+ * creation/removal and hierarchy changing operations including cgroup
+ * creation, removal, css association and controller rebinding.  This outer
+ * lock is needed mainly to resolve the circular dependency between kernfs
+ * active ref and cgroup_mutex.  cgroup_tree_mutex nests above both.
+ */
+static DEFINE_MUTEX(cgroup_tree_mutex);
+
 /*
  * cgroup_mutex is the master lock.  Any modification to cgroup or its
  * hierarchy must be performed while holding it.
  *
- * cgroup_root_mutex nests inside cgroup_mutex and should be held to modify
- * cgroupfs_root of any cgroup hierarchy - subsys list, flags,
- * release_agent_path and so on.  Modifying requires both cgroup_mutex and
- * cgroup_root_mutex.  Readers can acquire either of the two.  This is to
- * break the following locking order cycle.
+ * css_set_rwsem protects task->cgroups pointer, the list of css_set
+ * objects, and the chain of tasks off each css_set.
  *
- *  A. cgroup_mutex -> cred_guard_mutex -> s_type->i_mutex_key -> namespace_sem
- *  B. namespace_sem -> cgroup_mutex
- *
- * B happens only through cgroup_show_options() and using cgroup_root_mutex
- * breaks it.
+ * These locks are exported if CONFIG_PROVE_RCU so that accessors in
+ * cgroup.h can use them for lockdep annotations.
  */
 #ifdef CONFIG_PROVE_RCU
 DEFINE_MUTEX(cgroup_mutex);
-EXPORT_SYMBOL_GPL(cgroup_mutex);	/* only for lockdep */
+DECLARE_RWSEM(css_set_rwsem);
+EXPORT_SYMBOL_GPL(cgroup_mutex);
+EXPORT_SYMBOL_GPL(css_set_rwsem);
 #else
 static DEFINE_MUTEX(cgroup_mutex);
+static DECLARE_RWSEM(css_set_rwsem);
 #endif
 
-static DEFINE_MUTEX(cgroup_root_mutex);
+/*
+ * Protects cgroup_subsys->release_agent_path.  Modifying it also requires
+ * cgroup_mutex.  Reading requires either cgroup_mutex or this spinlock.
+ */
+static DEFINE_SPINLOCK(release_agent_path_lock);
 
-#define cgroup_assert_mutex_or_rcu_locked()				\
+#define cgroup_assert_mutexes_or_rcu_locked()				\
 	rcu_lockdep_assert(rcu_read_lock_held() ||			\
+			   lockdep_is_held(&cgroup_tree_mutex) ||	\
 			   lockdep_is_held(&cgroup_mutex),		\
-			   "cgroup_mutex or RCU read lock required");
-
-#ifdef CONFIG_LOCKDEP
-#define cgroup_assert_mutex_or_root_locked()				\
-	WARN_ON_ONCE(debug_locks && (!lockdep_is_held(&cgroup_mutex) &&	\
-				     !lockdep_is_held(&cgroup_root_mutex)))
-#else
-#define cgroup_assert_mutex_or_root_locked()	do { } while (0)
-#endif
+			   "cgroup_[tree_]mutex or RCU read lock required");
 
 /*
  * cgroup destruction makes heavy use of work items and there can be a lot
@@ -120,42 +124,41 @@ static struct workqueue_struct *cgroup_destroy_wq;
  */
 static struct workqueue_struct *cgroup_pidlist_destroy_wq;
 
-/*
- * Generate an array of cgroup subsystem pointers. At boot time, this is
- * populated with the built in subsystems, and modular subsystems are
- * registered after that. The mutable section of this array is protected by
- * cgroup_mutex.
- */
-#define SUBSYS(_x) [_x ## _subsys_id] = &_x ## _subsys,
-#define IS_SUBSYS_ENABLED(option) IS_BUILTIN(option)
-static struct cgroup_subsys *cgroup_subsys[CGROUP_SUBSYS_COUNT] = {
+/* generate an array of cgroup subsystem pointers */
+#define SUBSYS(_x) [_x ## _cgrp_id] = &_x ## _cgrp_subsys,
+static struct cgroup_subsys *cgroup_subsys[] = {
 #include <linux/cgroup_subsys.h>
 };
+#undef SUBSYS
+
+/* array of cgroup subsystem names */
+#define SUBSYS(_x) [_x ## _cgrp_id] = #_x,
+static const char *cgroup_subsys_name[] = {
+#include <linux/cgroup_subsys.h>
+};
+#undef SUBSYS
 
 /*
- * The dummy hierarchy, reserved for the subsystems that are otherwise
+ * The default hierarchy, reserved for the subsystems that are otherwise
  * unattached - it never has more than a single cgroup, and all tasks are
  * part of that cgroup.
  */
-static struct cgroupfs_root cgroup_dummy_root;
+struct cgroup_root cgrp_dfl_root;
 
-/* dummy_top is a shorthand for the dummy hierarchy's top cgroup */
-static struct cgroup * const cgroup_dummy_top = &cgroup_dummy_root.top_cgroup;
+/*
+ * The default hierarchy always exists but is hidden until mounted for the
+ * first time.  This is for backward compatibility.
+ */
+static bool cgrp_dfl_root_visible;
 
 /* The list of hierarchy roots */
 
 static LIST_HEAD(cgroup_roots);
 static int cgroup_root_count;
 
-/*
- * Hierarchy ID allocation and mapping.  It follows the same exclusion
- * rules as other root ops - both cgroup_mutex and cgroup_root_mutex for
- * writes, either for reads.
- */
+/* hierarchy ID allocation and mapping, protected by cgroup_mutex */
 static DEFINE_IDR(cgroup_hierarchy_idr);
 
-static struct cgroup_name root_cgroup_name = { .name = "/" };
-
 /*
  * Assign a monotonically increasing serial number to cgroups.  It
  * guarantees cgroups with bigger numbers are newer than those with smaller
@@ -175,11 +178,13 @@ static int need_forkexit_callback __read_mostly;
 
 static struct cftype cgroup_base_files[];
 
+static void cgroup_put(struct cgroup *cgrp);
+static int rebind_subsystems(struct cgroup_root *dst_root,
+			     unsigned long ss_mask);
 static void cgroup_destroy_css_killed(struct cgroup *cgrp);
 static int cgroup_destroy_locked(struct cgroup *cgrp);
 static int cgroup_addrm_files(struct cgroup *cgrp, struct cftype cfts[],
 			      bool is_add);
-static int cgroup_file_release(struct inode *inode, struct file *file);
 static void cgroup_pidlist_destroy_all(struct cgroup *cgrp);
 
 /**
@@ -197,8 +202,9 @@ static struct cgroup_subsys_state *cgroup_css(struct cgroup *cgrp,
 					      struct cgroup_subsys *ss)
 {
 	if (ss)
-		return rcu_dereference_check(cgrp->subsys[ss->subsys_id],
-					     lockdep_is_held(&cgroup_mutex));
+		return rcu_dereference_check(cgrp->subsys[ss->id],
+					lockdep_is_held(&cgroup_tree_mutex) ||
+					lockdep_is_held(&cgroup_mutex));
 	else
 		return &cgrp->dummy_css;
 }
@@ -209,6 +215,27 @@ static inline bool cgroup_is_dead(const struct cgroup *cgrp)
 	return test_bit(CGRP_DEAD, &cgrp->flags);
 }
 
+struct cgroup_subsys_state *seq_css(struct seq_file *seq)
+{
+	struct kernfs_open_file *of = seq->private;
+	struct cgroup *cgrp = of->kn->parent->priv;
+	struct cftype *cft = seq_cft(seq);
+
+	/*
+	 * This is open and unprotected implementation of cgroup_css().
+	 * seq_css() is only called from a kernfs file operation which has
+	 * an active reference on the file.  Because all the subsystem
+	 * files are drained before a css is disassociated with a cgroup,
+	 * the matching css from the cgroup's subsys table is guaranteed to
+	 * be and stay valid until the enclosing operation is complete.
+	 */
+	if (cft->ss)
+		return rcu_dereference_raw(cgrp->subsys[cft->ss->id]);
+	else
+		return &cgrp->dummy_css;
+}
+EXPORT_SYMBOL_GPL(seq_css);
+
 /**
  * cgroup_is_descendant - test ancestry
  * @cgrp: the cgroup to be tested
@@ -227,7 +254,6 @@ bool cgroup_is_descendant(struct cgroup *cgrp, struct cgroup *ancestor)
 	}
 	return false;
 }
-EXPORT_SYMBOL_GPL(cgroup_is_descendant);
 
 static int cgroup_is_releasable(const struct cgroup *cgrp)
 {
@@ -254,54 +280,23 @@ static int notify_on_release(const struct cgroup *cgrp)
 	for ((ssid) = 0; (ssid) < CGROUP_SUBSYS_COUNT; (ssid)++)	\
 		if (!((css) = rcu_dereference_check(			\
 				(cgrp)->subsys[(ssid)],			\
+				lockdep_is_held(&cgroup_tree_mutex) ||	\
 				lockdep_is_held(&cgroup_mutex)))) { }	\
 		else
 
 /**
- * for_each_subsys - iterate all loaded cgroup subsystems
+ * for_each_subsys - iterate all enabled cgroup subsystems
  * @ss: the iteration cursor
  * @ssid: the index of @ss, CGROUP_SUBSYS_COUNT after reaching the end
- *
- * Iterates through all loaded subsystems.  Should be called under
- * cgroup_mutex or cgroup_root_mutex.
  */
 #define for_each_subsys(ss, ssid)					\
-	for (({ cgroup_assert_mutex_or_root_locked(); (ssid) = 0; });	\
-	     (ssid) < CGROUP_SUBSYS_COUNT; (ssid)++)			\
-		if (!((ss) = cgroup_subsys[(ssid)])) { }		\
-		else
-
-/**
- * for_each_builtin_subsys - iterate all built-in cgroup subsystems
- * @ss: the iteration cursor
- * @i: the index of @ss, CGROUP_BUILTIN_SUBSYS_COUNT after reaching the end
- *
- * Bulit-in subsystems are always present and iteration itself doesn't
- * require any synchronization.
- */
-#define for_each_builtin_subsys(ss, i)					\
-	for ((i) = 0; (i) < CGROUP_BUILTIN_SUBSYS_COUNT &&		\
-	     (((ss) = cgroup_subsys[i]) || true); (i)++)
+	for ((ssid) = 0; (ssid) < CGROUP_SUBSYS_COUNT &&		\
+	     (((ss) = cgroup_subsys[ssid]) || true); (ssid)++)
 
-/* iterate across the active hierarchies */
-#define for_each_active_root(root)					\
+/* iterate across the hierarchies */
+#define for_each_root(root)						\
 	list_for_each_entry((root), &cgroup_roots, root_list)
 
-static inline struct cgroup *__d_cgrp(struct dentry *dentry)
-{
-	return dentry->d_fsdata;
-}
-
-static inline struct cfent *__d_cfe(struct dentry *dentry)
-{
-	return dentry->d_fsdata;
-}
-
-static inline struct cftype *__d_cft(struct dentry *dentry)
-{
-	return __d_cfe(dentry)->type;
-}
-
 /**
  * cgroup_lock_live_group - take cgroup_mutex and check that cgrp is alive.
  * @cgrp: the cgroup to be checked for liveness
@@ -347,23 +342,23 @@ struct cgrp_cset_link {
 	struct list_head	cgrp_link;
 };
 
-/* The default css_set - used by init and its children prior to any
+/*
+ * The default css_set - used by init and its children prior to any
  * hierarchies being mounted. It contains a pointer to the root state
  * for each subsystem. Also used to anchor the list of css_sets. Not
  * reference-counted, to improve performance when child cgroups
  * haven't been created.
  */
+struct css_set init_css_set = {
+	.refcount		= ATOMIC_INIT(1),
+	.cgrp_links		= LIST_HEAD_INIT(init_css_set.cgrp_links),
+	.tasks			= LIST_HEAD_INIT(init_css_set.tasks),
+	.mg_tasks		= LIST_HEAD_INIT(init_css_set.mg_tasks),
+	.mg_preload_node	= LIST_HEAD_INIT(init_css_set.mg_preload_node),
+	.mg_node		= LIST_HEAD_INIT(init_css_set.mg_node),
+};
 
-static struct css_set init_css_set;
-static struct cgrp_cset_link init_cgrp_cset_link;
-
-/*
- * css_set_lock protects the list of css_set objects, and the chain of
- * tasks off each css_set.  Nests outside task->alloc_lock due to
- * css_task_iter_start().
- */
-static DEFINE_RWLOCK(css_set_lock);
-static int css_set_count;
+static int css_set_count	= 1;	/* 1 for init_css_set */
 
 /*
  * hash table for cgroup groups. This improves the performance to find
@@ -386,30 +381,14 @@ static unsigned long css_set_hash(struct cgroup_subsys_state *css[])
 	return key;
 }
 
-/*
- * We don't maintain the lists running through each css_set to its task
- * until after the first call to css_task_iter_start().  This reduces the
- * fork()/exit() overhead for people who have cgroups compiled into their
- * kernel but not actually in use.
- */
-static int use_task_css_set_links __read_mostly;
-
-static void __put_css_set(struct css_set *cset, int taskexit)
+static void put_css_set_locked(struct css_set *cset, bool taskexit)
 {
 	struct cgrp_cset_link *link, *tmp_link;
 
-	/*
-	 * Ensure that the refcount doesn't hit zero while any readers
-	 * can see it. Similar to atomic_dec_and_lock(), but for an
-	 * rwlock
-	 */
-	if (atomic_add_unless(&cset->refcount, -1, 1))
-		return;
-	write_lock(&css_set_lock);
-	if (!atomic_dec_and_test(&cset->refcount)) {
-		write_unlock(&css_set_lock);
+	lockdep_assert_held(&css_set_rwsem);
+
+	if (!atomic_dec_and_test(&cset->refcount))
 		return;
-	}
 
 	/* This css_set is dead. unlink it and release cgroup refcounts */
 	hash_del(&cset->hlist);
@@ -421,7 +400,7 @@ static void __put_css_set(struct css_set *cset, int taskexit)
 		list_del(&link->cset_link);
 		list_del(&link->cgrp_link);
 
-		/* @cgrp can't go away while we're holding css_set_lock */
+		/* @cgrp can't go away while we're holding css_set_rwsem */
 		if (list_empty(&cgrp->cset_links) && notify_on_release(cgrp)) {
 			if (taskexit)
 				set_bit(CGRP_RELEASABLE, &cgrp->flags);
@@ -431,10 +410,24 @@ static void __put_css_set(struct css_set *cset, int taskexit)
 		kfree(link);
 	}
 
-	write_unlock(&css_set_lock);
 	kfree_rcu(cset, rcu_head);
 }
 
+static void put_css_set(struct css_set *cset, bool taskexit)
+{
+	/*
+	 * Ensure that the refcount doesn't hit zero while any readers
+	 * can see it. Similar to atomic_dec_and_lock(), but for an
+	 * rwlock
+	 */
+	if (atomic_add_unless(&cset->refcount, -1, 1))
+		return;
+
+	down_write(&css_set_rwsem);
+	put_css_set_locked(cset, taskexit);
+	up_write(&css_set_rwsem);
+}
+
 /*
  * refcounted get/put for css_set objects
  */
@@ -443,16 +436,6 @@ static inline void get_css_set(struct css_set *cset)
 	atomic_inc(&cset->refcount);
 }
 
-static inline void put_css_set(struct css_set *cset)
-{
-	__put_css_set(cset, 0);
-}
-
-static inline void put_css_set_taskexit(struct css_set *cset)
-{
-	__put_css_set(cset, 1);
-}
-
 /**
  * compare_css_sets - helper function for find_existing_css_set().
  * @cset: candidate css_set being tested
@@ -535,7 +518,7 @@ static struct css_set *find_existing_css_set(struct css_set *old_cset,
 					struct cgroup *cgrp,
 					struct cgroup_subsys_state *template[])
 {
-	struct cgroupfs_root *root = cgrp->root;
+	struct cgroup_root *root = cgrp->root;
 	struct cgroup_subsys *ss;
 	struct css_set *cset;
 	unsigned long key;
@@ -547,7 +530,7 @@ static struct css_set *find_existing_css_set(struct css_set *old_cset,
 	 * won't change, so no need for locking.
 	 */
 	for_each_subsys(ss, i) {
-		if (root->subsys_mask & (1UL << i)) {
+		if (root->cgrp.subsys_mask & (1UL << i)) {
 			/* Subsystem is in this hierarchy. So we want
 			 * the subsystem state from the new
 			 * cgroup */
@@ -652,11 +635,11 @@ static struct css_set *find_css_set(struct css_set *old_cset,
 
 	/* First see if we already have a cgroup group that matches
 	 * the desired set */
-	read_lock(&css_set_lock);
+	down_read(&css_set_rwsem);
 	cset = find_existing_css_set(old_cset, cgrp, template);
 	if (cset)
 		get_css_set(cset);
-	read_unlock(&css_set_lock);
+	up_read(&css_set_rwsem);
 
 	if (cset)
 		return cset;
@@ -674,13 +657,16 @@ static struct css_set *find_css_set(struct css_set *old_cset,
 	atomic_set(&cset->refcount, 1);
 	INIT_LIST_HEAD(&cset->cgrp_links);
 	INIT_LIST_HEAD(&cset->tasks);
+	INIT_LIST_HEAD(&cset->mg_tasks);
+	INIT_LIST_HEAD(&cset->mg_preload_node);
+	INIT_LIST_HEAD(&cset->mg_node);
 	INIT_HLIST_NODE(&cset->hlist);
 
 	/* Copy the set of subsystem state objects generated in
 	 * find_existing_css_set() */
 	memcpy(cset->subsys, template, sizeof(cset->subsys));
 
-	write_lock(&css_set_lock);
+	down_write(&css_set_rwsem);
 	/* Add reference counts and links from the new css_set. */
 	list_for_each_entry(link, &old_cset->cgrp_links, cgrp_link) {
 		struct cgroup *c = link->cgrp;
@@ -698,31 +684,105 @@ static struct css_set *find_css_set(struct css_set *old_cset,
 	key = css_set_hash(cset->subsys);
 	hash_add(css_set_table, &cset->hlist, key);
 
-	write_unlock(&css_set_lock);
+	up_write(&css_set_rwsem);
 
 	return cset;
 }
 
-/*
- * Return the cgroup for "task" from the given hierarchy. Must be
- * called with cgroup_mutex held.
- */
-static struct cgroup *task_cgroup_from_root(struct task_struct *task,
-					    struct cgroupfs_root *root)
+static struct cgroup_root *cgroup_root_from_kf(struct kernfs_root *kf_root)
 {
-	struct css_set *cset;
-	struct cgroup *res = NULL;
+	struct cgroup *root_cgrp = kf_root->kn->priv;
+
+	return root_cgrp->root;
+}
+
+static int cgroup_init_root_id(struct cgroup_root *root)
+{
+	int id;
+
+	lockdep_assert_held(&cgroup_mutex);
+
+	id = idr_alloc_cyclic(&cgroup_hierarchy_idr, root, 0, 0, GFP_KERNEL);
+	if (id < 0)
+		return id;
+
+	root->hierarchy_id = id;
+	return 0;
+}
+
+static void cgroup_exit_root_id(struct cgroup_root *root)
+{
+	lockdep_assert_held(&cgroup_mutex);
+
+	if (root->hierarchy_id) {
+		idr_remove(&cgroup_hierarchy_idr, root->hierarchy_id);
+		root->hierarchy_id = 0;
+	}
+}
+
+static void cgroup_free_root(struct cgroup_root *root)
+{
+	if (root) {
+		/* hierarhcy ID shoulid already have been released */
+		WARN_ON_ONCE(root->hierarchy_id);
+
+		idr_destroy(&root->cgroup_idr);
+		kfree(root);
+	}
+}
+
+static void cgroup_destroy_root(struct cgroup_root *root)
+{
+	struct cgroup *cgrp = &root->cgrp;
+	struct cgrp_cset_link *link, *tmp_link;
+
+	mutex_lock(&cgroup_tree_mutex);
+	mutex_lock(&cgroup_mutex);
+
+	BUG_ON(atomic_read(&root->nr_cgrps));
+	BUG_ON(!list_empty(&cgrp->children));
+
+	/* Rebind all subsystems back to the default hierarchy */
+	rebind_subsystems(&cgrp_dfl_root, cgrp->subsys_mask);
 
-	BUG_ON(!mutex_is_locked(&cgroup_mutex));
-	read_lock(&css_set_lock);
 	/*
-	 * No need to lock the task - since we hold cgroup_mutex the
-	 * task can't change groups, so the only thing that can happen
-	 * is that it exits and its css is set back to init_css_set.
+	 * Release all the links from cset_links to this hierarchy's
+	 * root cgroup
 	 */
-	cset = task_css_set(task);
+	down_write(&css_set_rwsem);
+
+	list_for_each_entry_safe(link, tmp_link, &cgrp->cset_links, cset_link) {
+		list_del(&link->cset_link);
+		list_del(&link->cgrp_link);
+		kfree(link);
+	}
+	up_write(&css_set_rwsem);
+
+	if (!list_empty(&root->root_list)) {
+		list_del(&root->root_list);
+		cgroup_root_count--;
+	}
+
+	cgroup_exit_root_id(root);
+
+	mutex_unlock(&cgroup_mutex);
+	mutex_unlock(&cgroup_tree_mutex);
+
+	kernfs_destroy_root(root->kf_root);
+	cgroup_free_root(root);
+}
+
+/* look up cgroup associated with given css_set on the specified hierarchy */
+static struct cgroup *cset_cgroup_from_root(struct css_set *cset,
+					    struct cgroup_root *root)
+{
+	struct cgroup *res = NULL;
+
+	lockdep_assert_held(&cgroup_mutex);
+	lockdep_assert_held(&css_set_rwsem);
+
 	if (cset == &init_css_set) {
-		res = &root->top_cgroup;
+		res = &root->cgrp;
 	} else {
 		struct cgrp_cset_link *link;
 
@@ -735,16 +795,27 @@ static struct cgroup *task_cgroup_from_root(struct task_struct *task,
 			}
 		}
 	}
-	read_unlock(&css_set_lock);
+
 	BUG_ON(!res);
 	return res;
 }
 
 /*
- * There is one global cgroup mutex. We also require taking
- * task_lock() when dereferencing a task's cgroup subsys pointers.
- * See "The task_lock() exception", at the end of this comment.
- *
+ * Return the cgroup for "task" from the given hierarchy. Must be
+ * called with cgroup_mutex and css_set_rwsem held.
+ */
+static struct cgroup *task_cgroup_from_root(struct task_struct *task,
+					    struct cgroup_root *root)
+{
+	/*
+	 * No need to lock the task - since we hold cgroup_mutex the
+	 * task can't change groups, so the only thing that can happen
+	 * is that it exits and its css is set back to init_css_set.
+	 */
+	return cset_cgroup_from_root(task_css_set(task), root);
+}
+
+/*
  * A task must hold cgroup_mutex to modify cgroups.
  *
  * Any task can increment and decrement the count field without lock.
@@ -770,98 +841,79 @@ static struct cgroup *task_cgroup_from_root(struct task_struct *task,
  * A cgroup can only be deleted if both its 'count' of using tasks
  * is zero, and its list of 'children' cgroups is empty.  Since all
  * tasks in the system use _some_ cgroup, and since there is always at
- * least one task in the system (init, pid == 1), therefore, top_cgroup
+ * least one task in the system (init, pid == 1), therefore, root cgroup
  * always has either children cgroups and/or using tasks.  So we don't
- * need a special hack to ensure that top_cgroup cannot be deleted.
- *
- *	The task_lock() exception
- *
- * The need for this exception arises from the action of
- * cgroup_attach_task(), which overwrites one task's cgroup pointer with
- * another.  It does so using cgroup_mutex, however there are
- * several performance critical places that need to reference
- * task->cgroup without the expense of grabbing a system global
- * mutex.  Therefore except as noted below, when dereferencing or, as
- * in cgroup_attach_task(), modifying a task's cgroup pointer we use
- * task_lock(), which acts on a spinlock (task->alloc_lock) already in
- * the task_struct routinely used for such matters.
+ * need a special hack to ensure that root cgroup cannot be deleted.
  *
  * P.S.  One more locking exception.  RCU is used to guard the
  * update of a tasks cgroup pointer by cgroup_attach_task()
  */
 
-/*
- * A couple of forward declarations required, due to cyclic reference loop:
- * cgroup_mkdir -> cgroup_create -> cgroup_populate_dir ->
- * cgroup_add_file -> cgroup_create_file -> cgroup_dir_inode_operations
- * -> cgroup_mkdir.
- */
-
-static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode);
-static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry);
 static int cgroup_populate_dir(struct cgroup *cgrp, unsigned long subsys_mask);
-static const struct inode_operations cgroup_dir_inode_operations;
+static struct kernfs_syscall_ops cgroup_kf_syscall_ops;
 static const struct file_operations proc_cgroupstats_operations;
 
-static struct backing_dev_info cgroup_backing_dev_info = {
-	.name		= "cgroup",
-	.capabilities	= BDI_CAP_NO_ACCT_AND_WRITEBACK,
-};
-
-static struct inode *cgroup_new_inode(umode_t mode, struct super_block *sb)
+static char *cgroup_file_name(struct cgroup *cgrp, const struct cftype *cft,
+			      char *buf)
 {
-	struct inode *inode = new_inode(sb);
-
-	if (inode) {
-		inode->i_ino = get_next_ino();
-		inode->i_mode = mode;
-		inode->i_uid = current_fsuid();
-		inode->i_gid = current_fsgid();
-		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
-		inode->i_mapping->backing_dev_info = &cgroup_backing_dev_info;
-	}
-	return inode;
+	if (cft->ss && !(cft->flags & CFTYPE_NO_PREFIX) &&
+	    !(cgrp->root->flags & CGRP_ROOT_NOPREFIX))
+		snprintf(buf, CGROUP_FILE_NAME_MAX, "%s.%s",
+			 cft->ss->name, cft->name);
+	else
+		strncpy(buf, cft->name, CGROUP_FILE_NAME_MAX);
+	return buf;
 }
 
-static struct cgroup_name *cgroup_alloc_name(struct dentry *dentry)
+/**
+ * cgroup_file_mode - deduce file mode of a control file
+ * @cft: the control file in question
+ *
+ * returns cft->mode if ->mode is not 0
+ * returns S_IRUGO|S_IWUSR if it has both a read and a write handler
+ * returns S_IRUGO if it has only a read handler
+ * returns S_IWUSR if it has only a write hander
+ */
+static umode_t cgroup_file_mode(const struct cftype *cft)
 {
-	struct cgroup_name *name;
+	umode_t mode = 0;
 
-	name = kmalloc(sizeof(*name) + dentry->d_name.len + 1, GFP_KERNEL);
-	if (!name)
-		return NULL;
-	strcpy(name->name, dentry->d_name.name);
-	return name;
+	if (cft->mode)
+		return cft->mode;
+
+	if (cft->read_u64 || cft->read_s64 || cft->seq_show)
+		mode |= S_IRUGO;
+
+	if (cft->write_u64 || cft->write_s64 || cft->write_string ||
+	    cft->trigger)
+		mode |= S_IWUSR;
+
+	return mode;
 }
 
 static void cgroup_free_fn(struct work_struct *work)
 {
 	struct cgroup *cgrp = container_of(work, struct cgroup, destroy_work);
 
-	mutex_lock(&cgroup_mutex);
-	cgrp->root->number_of_cgroups--;
-	mutex_unlock(&cgroup_mutex);
-
-	/*
-	 * We get a ref to the parent's dentry, and put the ref when
-	 * this cgroup is being freed, so it's guaranteed that the
-	 * parent won't be destroyed before its children.
-	 */
-	dput(cgrp->parent->dentry);
-
-	/*
-	 * Drop the active superblock reference that we took when we
-	 * created the cgroup. This will free cgrp->root, if we are
-	 * holding the last reference to @sb.
-	 */
-	deactivate_super(cgrp->root->sb);
-
+	atomic_dec(&cgrp->root->nr_cgrps);
 	cgroup_pidlist_destroy_all(cgrp);
 
-	simple_xattrs_free(&cgrp->xattrs);
-
-	kfree(rcu_dereference_raw(cgrp->name));
-	kfree(cgrp);
+	if (cgrp->parent) {
+		/*
+		 * We get a ref to the parent, and put the ref when this
+		 * cgroup is being freed, so it's guaranteed that the
+		 * parent won't be destroyed before its children.
+		 */
+		cgroup_put(cgrp->parent);
+		kernfs_put(cgrp->kn);
+		kfree(cgrp);
+	} else {
+		/*
+		 * This is root cgroup's refcnt reaching zero, which
+		 * indicates that the root should be released.
+		 */
+		cgroup_destroy_root(cgrp->root);
+	}
 }
 
 static void cgroup_free_rcu(struct rcu_head *head)
@@ -872,73 +924,40 @@ static void cgroup_free_rcu(struct rcu_head *head)
 	queue_work(cgroup_destroy_wq, &cgrp->destroy_work);
 }
 
-static void cgroup_diput(struct dentry *dentry, struct inode *inode)
+static void cgroup_get(struct cgroup *cgrp)
 {
-	/* is dentry a directory ? if so, kfree() associated cgroup */
-	if (S_ISDIR(inode->i_mode)) {
-		struct cgroup *cgrp = dentry->d_fsdata;
-
-		BUG_ON(!(cgroup_is_dead(cgrp)));
-
-		/*
-		 * XXX: cgrp->id is only used to look up css's.  As cgroup
-		 * and css's lifetimes will be decoupled, it should be made
-		 * per-subsystem and moved to css->id so that lookups are
-		 * successful until the target css is released.
-		 */
-		mutex_lock(&cgroup_mutex);
-		idr_remove(&cgrp->root->cgroup_idr, cgrp->id);
-		mutex_unlock(&cgroup_mutex);
-		cgrp->id = -1;
-
-		call_rcu(&cgrp->rcu_head, cgroup_free_rcu);
-	} else {
-		struct cfent *cfe = __d_cfe(dentry);
-		struct cgroup *cgrp = dentry->d_parent->d_fsdata;
-
-		WARN_ONCE(!list_empty(&cfe->node) &&
-			  cgrp != &cgrp->root->top_cgroup,
-			  "cfe still linked for %s\n", cfe->type->name);
-		simple_xattrs_free(&cfe->xattrs);
-		kfree(cfe);
-	}
-	iput(inode);
+	WARN_ON_ONCE(cgroup_is_dead(cgrp));
+	WARN_ON_ONCE(atomic_read(&cgrp->refcnt) <= 0);
+	atomic_inc(&cgrp->refcnt);
 }
 
-static void remove_dir(struct dentry *d)
+static void cgroup_put(struct cgroup *cgrp)
 {
-	struct dentry *parent = dget(d->d_parent);
-
-	d_delete(d);
-	simple_rmdir(parent->d_inode, d);
-	dput(parent);
-}
-
-static void cgroup_rm_file(struct cgroup *cgrp, const struct cftype *cft)
-{
-	struct cfent *cfe;
-
-	lockdep_assert_held(&cgrp->dentry->d_inode->i_mutex);
-	lockdep_assert_held(&cgroup_mutex);
+	if (!atomic_dec_and_test(&cgrp->refcnt))
+		return;
+	if (WARN_ON_ONCE(cgrp->parent && !cgroup_is_dead(cgrp)))
+		return;
 
 	/*
-	 * If we're doing cleanup due to failure of cgroup_create(),
-	 * the corresponding @cfe may not exist.
+	 * XXX: cgrp->id is only used to look up css's.  As cgroup and
+	 * css's lifetimes will be decoupled, it should be made
+	 * per-subsystem and moved to css->id so that lookups are
+	 * successful until the target css is released.
 	 */
-	list_for_each_entry(cfe, &cgrp->files, node) {
-		struct dentry *d = cfe->dentry;
+	mutex_lock(&cgroup_mutex);
+	idr_remove(&cgrp->root->cgroup_idr, cgrp->id);
+	mutex_unlock(&cgroup_mutex);
+	cgrp->id = -1;
 
-		if (cft && cfe->type != cft)
-			continue;
+	call_rcu(&cgrp->rcu_head, cgroup_free_rcu);
+}
 
-		dget(d);
-		d_delete(d);
-		simple_unlink(cgrp->dentry->d_inode, d);
-		list_del_init(&cfe->node);
-		dput(d);
+static void cgroup_rm_file(struct cgroup *cgrp, const struct cftype *cft)
+{
+	char name[CGROUP_FILE_NAME_MAX];
 
-		break;
-	}
+	lockdep_assert_held(&cgroup_tree_mutex);
+	kernfs_remove_by_name(cgrp->kn, cgroup_file_name(cgrp, cft, name));
 }
 
 /**
@@ -952,144 +971,106 @@ static void cgroup_clear_dir(struct cgroup *cgrp, unsigned long subsys_mask)
 	int i;
 
 	for_each_subsys(ss, i) {
-		struct cftype_set *set;
+		struct cftype *cfts;
 
 		if (!test_bit(i, &subsys_mask))
 			continue;
-		list_for_each_entry(set, &ss->cftsets, node)
-			cgroup_addrm_files(cgrp, set->cfts, false);
+		list_for_each_entry(cfts, &ss->cfts, node)
+			cgroup_addrm_files(cgrp, cfts, false);
 	}
 }
 
-/*
- * NOTE : the dentry must have been dget()'ed
- */
-static void cgroup_d_remove_dir(struct dentry *dentry)
+static int rebind_subsystems(struct cgroup_root *dst_root,
+			     unsigned long ss_mask)
 {
-	struct dentry *parent;
-
-	parent = dentry->d_parent;
-	spin_lock(&parent->d_lock);
-	spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
-	list_del_init(&dentry->d_u.d_child);
-	spin_unlock(&dentry->d_lock);
-	spin_unlock(&parent->d_lock);
-	remove_dir(dentry);
-}
-
-/*
- * Call with cgroup_mutex held. Drops reference counts on modules, including
- * any duplicate ones that parse_cgroupfs_options took. If this function
- * returns an error, no reference counts are touched.
- */
-static int rebind_subsystems(struct cgroupfs_root *root,
-			     unsigned long added_mask, unsigned removed_mask)
-{
-	struct cgroup *cgrp = &root->top_cgroup;
 	struct cgroup_subsys *ss;
-	unsigned long pinned = 0;
-	int i, ret;
+	int ssid, ret;
 
-	BUG_ON(!mutex_is_locked(&cgroup_mutex));
-	BUG_ON(!mutex_is_locked(&cgroup_root_mutex));
+	lockdep_assert_held(&cgroup_tree_mutex);
+	lockdep_assert_held(&cgroup_mutex);
 
-	/* Check that any added subsystems are currently free */
-	for_each_subsys(ss, i) {
-		if (!(added_mask & (1 << i)))
+	for_each_subsys(ss, ssid) {
+		if (!(ss_mask & (1 << ssid)))
 			continue;
 
-		/* is the subsystem mounted elsewhere? */
-		if (ss->root != &cgroup_dummy_root) {
-			ret = -EBUSY;
-			goto out_put;
-		}
+		/* if @ss is on the dummy_root, we can always move it */
+		if (ss->root == &cgrp_dfl_root)
+			continue;
 
-		/* pin the module */
-		if (!try_module_get(ss->module)) {
-			ret = -ENOENT;
-			goto out_put;
-		}
-		pinned |= 1 << i;
-	}
+		/* if @ss has non-root cgroups attached to it, can't move */
+		if (!list_empty(&ss->root->cgrp.children))
+			return -EBUSY;
 
-	/* subsys could be missing if unloaded between parsing and here */
-	if (added_mask != pinned) {
-		ret = -ENOENT;
-		goto out_put;
+		/* can't move between two non-dummy roots either */
+		if (dst_root != &cgrp_dfl_root)
+			return -EBUSY;
 	}
 
-	ret = cgroup_populate_dir(cgrp, added_mask);
-	if (ret)
-		goto out_put;
+	ret = cgroup_populate_dir(&dst_root->cgrp, ss_mask);
+	if (ret) {
+		if (dst_root != &cgrp_dfl_root)
+			return ret;
+
+		/*
+		 * Rebinding back to the default root is not allowed to
+		 * fail.  Using both default and non-default roots should
+		 * be rare.  Moving subsystems back and forth even more so.
+		 * Just warn about it and continue.
+		 */
+		if (cgrp_dfl_root_visible) {
+			pr_warning("cgroup: failed to create files (%d) while rebinding 0x%lx to default root\n",
+				   ret, ss_mask);
+			pr_warning("cgroup: you may retry by moving them to a different hierarchy and unbinding\n");
+		}
+	}
 
 	/*
 	 * Nothing can fail from this point on.  Remove files for the
 	 * removed subsystems and rebind each subsystem.
 	 */
-	cgroup_clear_dir(cgrp, removed_mask);
-
-	for_each_subsys(ss, i) {
-		unsigned long bit = 1UL << i;
-
-		if (bit & added_mask) {
-			/* We're binding this subsystem to this hierarchy */
-			BUG_ON(cgroup_css(cgrp, ss));
-			BUG_ON(!cgroup_css(cgroup_dummy_top, ss));
-			BUG_ON(cgroup_css(cgroup_dummy_top, ss)->cgroup != cgroup_dummy_top);
+	mutex_unlock(&cgroup_mutex);
+	for_each_subsys(ss, ssid)
+		if (ss_mask & (1 << ssid))
+			cgroup_clear_dir(&ss->root->cgrp, 1 << ssid);
+	mutex_lock(&cgroup_mutex);
 
-			rcu_assign_pointer(cgrp->subsys[i],
-					   cgroup_css(cgroup_dummy_top, ss));
-			cgroup_css(cgrp, ss)->cgroup = cgrp;
+	for_each_subsys(ss, ssid) {
+		struct cgroup_root *src_root;
+		struct cgroup_subsys_state *css;
 
-			ss->root = root;
-			if (ss->bind)
-				ss->bind(cgroup_css(cgrp, ss));
+		if (!(ss_mask & (1 << ssid)))
+			continue;
 
-			/* refcount was already taken, and we're keeping it */
-			root->subsys_mask |= bit;
-		} else if (bit & removed_mask) {
-			/* We're removing this subsystem */
-			BUG_ON(cgroup_css(cgrp, ss) != cgroup_css(cgroup_dummy_top, ss));
-			BUG_ON(cgroup_css(cgrp, ss)->cgroup != cgrp);
+		src_root = ss->root;
+		css = cgroup_css(&src_root->cgrp, ss);
 
-			if (ss->bind)
-				ss->bind(cgroup_css(cgroup_dummy_top, ss));
+		WARN_ON(!css || cgroup_css(&dst_root->cgrp, ss));
 
-			cgroup_css(cgroup_dummy_top, ss)->cgroup = cgroup_dummy_top;
-			RCU_INIT_POINTER(cgrp->subsys[i], NULL);
+		RCU_INIT_POINTER(src_root->cgrp.subsys[ssid], NULL);
+		rcu_assign_pointer(dst_root->cgrp.subsys[ssid], css);
+		ss->root = dst_root;
+		css->cgroup = &dst_root->cgrp;
 
-			cgroup_subsys[i]->root = &cgroup_dummy_root;
+		src_root->cgrp.subsys_mask &= ~(1 << ssid);
+		dst_root->cgrp.subsys_mask |= 1 << ssid;
 
-			/* subsystem is now free - drop reference on module */
-			module_put(ss->module);
-			root->subsys_mask &= ~bit;
-		}
+		if (ss->bind)
+			ss->bind(css);
 	}
 
-	/*
-	 * Mark @root has finished binding subsystems.  @root->subsys_mask
-	 * now matches the bound subsystems.
-	 */
-	root->flags |= CGRP_ROOT_SUBSYS_BOUND;
-
+	kernfs_activate(dst_root->cgrp.kn);
 	return 0;
-
-out_put:
-	for_each_subsys(ss, i)
-		if (pinned & (1 << i))
-			module_put(ss->module);
-	return ret;
 }
 
-static int cgroup_show_options(struct seq_file *seq, struct dentry *dentry)
+static int cgroup_show_options(struct seq_file *seq,
+			       struct kernfs_root *kf_root)
 {
-	struct cgroupfs_root *root = dentry->d_sb->s_fs_info;
+	struct cgroup_root *root = cgroup_root_from_kf(kf_root);
 	struct cgroup_subsys *ss;
 	int ssid;
 
-	mutex_lock(&cgroup_root_mutex);
 	for_each_subsys(ss, ssid)
-		if (root->subsys_mask & (1 << ssid))
+		if (root->cgrp.subsys_mask & (1 << ssid))
 			seq_printf(seq, ",%s", ss->name);
 	if (root->flags & CGRP_ROOT_SANE_BEHAVIOR)
 		seq_puts(seq, ",sane_behavior");
@@ -1097,13 +1078,16 @@ static int cgroup_show_options(struct seq_file *seq, struct dentry *dentry)
 		seq_puts(seq, ",noprefix");
 	if (root->flags & CGRP_ROOT_XATTR)
 		seq_puts(seq, ",xattr");
+
+	spin_lock(&release_agent_path_lock);
 	if (strlen(root->release_agent_path))
 		seq_printf(seq, ",release_agent=%s", root->release_agent_path);
-	if (test_bit(CGRP_CPUSET_CLONE_CHILDREN, &root->top_cgroup.flags))
+	spin_unlock(&release_agent_path_lock);
+
+	if (test_bit(CGRP_CPUSET_CLONE_CHILDREN, &root->cgrp.flags))
 		seq_puts(seq, ",clone_children");
 	if (strlen(root->name))
 		seq_printf(seq, ",name=%s", root->name);
-	mutex_unlock(&cgroup_root_mutex);
 	return 0;
 }
 
@@ -1115,9 +1099,6 @@ struct cgroup_sb_opts {
 	char *name;
 	/* User explicitly requested empty subsystem */
 	bool none;
-
-	struct cgroupfs_root *new_root;
-
 };
 
 /*
@@ -1137,7 +1118,7 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts)
 	BUG_ON(!mutex_is_locked(&cgroup_mutex));
 
 #ifdef CONFIG_CPUSETS
-	mask = ~(1UL << cpuset_subsys_id);
+	mask = ~(1UL << cpuset_cgrp_id);
 #endif
 
 	memset(opts, 0, sizeof(*opts));
@@ -1227,30 +1208,34 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts)
 			return -ENOENT;
 	}
 
-	/*
-	 * If the 'all' option was specified select all the subsystems,
-	 * otherwise if 'none', 'name=' and a subsystem name options
-	 * were not specified, let's default to 'all'
-	 */
-	if (all_ss || (!one_ss && !opts->none && !opts->name))
-		for_each_subsys(ss, i)
-			if (!ss->disabled)
-				set_bit(i, &opts->subsys_mask);
-
 	/* Consistency checks */
 
 	if (opts->flags & CGRP_ROOT_SANE_BEHAVIOR) {
 		pr_warning("cgroup: sane_behavior: this is still under development and its behaviors will change, proceed at your own risk\n");
 
-		if (opts->flags & CGRP_ROOT_NOPREFIX) {
-			pr_err("cgroup: sane_behavior: noprefix is not allowed\n");
+		if ((opts->flags & (CGRP_ROOT_NOPREFIX | CGRP_ROOT_XATTR)) ||
+		    opts->cpuset_clone_children || opts->release_agent ||
+		    opts->name) {
+			pr_err("cgroup: sane_behavior: noprefix, xattr, clone_children, release_agent and name are not allowed\n");
 			return -EINVAL;
 		}
+	} else {
+		/*
+		 * If the 'all' option was specified select all the
+		 * subsystems, otherwise if 'none', 'name=' and a subsystem
+		 * name options were not specified, let's default to 'all'
+		 */
+		if (all_ss || (!one_ss && !opts->none && !opts->name))
+			for_each_subsys(ss, i)
+				if (!ss->disabled)
+					set_bit(i, &opts->subsys_mask);
 
-		if (opts->cpuset_clone_children) {
-			pr_err("cgroup: sane_behavior: clone_children is not allowed\n");
+		/*
+		 * We either have to specify by name or by subsystems. (So
+		 * all empty hierarchies must have a name).
+		 */
+		if (!opts->subsys_mask && !opts->name)
 			return -EINVAL;
-		}
 	}
 
 	/*
@@ -1266,21 +1251,13 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts)
 	if (opts->subsys_mask && opts->none)
 		return -EINVAL;
 
-	/*
-	 * We either have to specify by name or by subsystems. (So all
-	 * empty hierarchies must have a name).
-	 */
-	if (!opts->subsys_mask && !opts->name)
-		return -EINVAL;
-
 	return 0;
 }
 
-static int cgroup_remount(struct super_block *sb, int *flags, char *data)
+static int cgroup_remount(struct kernfs_root *kf_root, int *flags, char *data)
 {
 	int ret = 0;
-	struct cgroupfs_root *root = sb->s_fs_info;
-	struct cgroup *cgrp = &root->top_cgroup;
+	struct cgroup_root *root = cgroup_root_from_kf(kf_root);
 	struct cgroup_sb_opts opts;
 	unsigned long added_mask, removed_mask;
 
@@ -1289,21 +1266,20 @@ static int cgroup_remount(struct super_block *sb, int *flags, char *data)
 		return -EINVAL;
 	}
 
-	mutex_lock(&cgrp->dentry->d_inode->i_mutex);
+	mutex_lock(&cgroup_tree_mutex);
 	mutex_lock(&cgroup_mutex);
-	mutex_lock(&cgroup_root_mutex);
 
 	/* See what subsystems are wanted */
 	ret = parse_cgroupfs_options(data, &opts);
 	if (ret)
 		goto out_unlock;
 
-	if (opts.subsys_mask != root->subsys_mask || opts.release_agent)
+	if (opts.subsys_mask != root->cgrp.subsys_mask || opts.release_agent)
 		pr_warning("cgroup: option changes via remount are deprecated (pid=%d comm=%s)\n",
 			   task_tgid_nr(current), current->comm);
 
-	added_mask = opts.subsys_mask & ~root->subsys_mask;
-	removed_mask = root->subsys_mask & ~opts.subsys_mask;
+	added_mask = opts.subsys_mask & ~root->cgrp.subsys_mask;
+	removed_mask = root->cgrp.subsys_mask & ~opts.subsys_mask;
 
 	/* Don't allow flags or name to change at remount */
 	if (((opts.flags ^ root->flags) & CGRP_ROOT_OPTION_MASK) ||
@@ -1316,422 +1292,333 @@ static int cgroup_remount(struct super_block *sb, int *flags, char *data)
 	}
 
 	/* remounting is not allowed for populated hierarchies */
-	if (root->number_of_cgroups > 1) {
+	if (!list_empty(&root->cgrp.children)) {
 		ret = -EBUSY;
 		goto out_unlock;
 	}
 
-	ret = rebind_subsystems(root, added_mask, removed_mask);
+	ret = rebind_subsystems(root, added_mask);
 	if (ret)
 		goto out_unlock;
 
-	if (opts.release_agent)
+	rebind_subsystems(&cgrp_dfl_root, removed_mask);
+
+	if (opts.release_agent) {
+		spin_lock(&release_agent_path_lock);
 		strcpy(root->release_agent_path, opts.release_agent);
+		spin_unlock(&release_agent_path_lock);
+	}
  out_unlock:
 	kfree(opts.release_agent);
 	kfree(opts.name);
-	mutex_unlock(&cgroup_root_mutex);
 	mutex_unlock(&cgroup_mutex);
-	mutex_unlock(&cgrp->dentry->d_inode->i_mutex);
+	mutex_unlock(&cgroup_tree_mutex);
 	return ret;
 }
 
-static const struct super_operations cgroup_ops = {
-	.statfs = simple_statfs,
-	.drop_inode = generic_delete_inode,
-	.show_options = cgroup_show_options,
-	.remount_fs = cgroup_remount,
-};
+/*
+ * To reduce the fork() overhead for systems that are not actually using
+ * their cgroups capability, we don't maintain the lists running through
+ * each css_set to its tasks until we see the list actually used - in other
+ * words after the first mount.
+ */
+static bool use_task_css_set_links __read_mostly;
+
+static void cgroup_enable_task_cg_lists(void)
+{
+	struct task_struct *p, *g;
+
+	down_write(&css_set_rwsem);
+
+	if (use_task_css_set_links)
+		goto out_unlock;
+
+	use_task_css_set_links = true;
+
+	/*
+	 * We need tasklist_lock because RCU is not safe against
+	 * while_each_thread(). Besides, a forking task that has passed
+	 * cgroup_post_fork() without seeing use_task_css_set_links = 1
+	 * is not guaranteed to have its child immediately visible in the
+	 * tasklist if we walk through it with RCU.
+	 */
+	read_lock(&tasklist_lock);
+	do_each_thread(g, p) {
+		WARN_ON_ONCE(!list_empty(&p->cg_list) ||
+			     task_css_set(p) != &init_css_set);
+
+		/*
+		 * We should check if the process is exiting, otherwise
+		 * it will race with cgroup_exit() in that the list
+		 * entry won't be deleted though the process has exited.
+		 * Do it while holding siglock so that we don't end up
+		 * racing against cgroup_exit().
+		 */
+		spin_lock_irq(&p->sighand->siglock);
+		if (!(p->flags & PF_EXITING)) {
+			struct css_set *cset = task_css_set(p);
+
+			list_add(&p->cg_list, &cset->tasks);
+			get_css_set(cset);
+		}
+		spin_unlock_irq(&p->sighand->siglock);
+	} while_each_thread(g, p);
+	read_unlock(&tasklist_lock);
+out_unlock:
+	up_write(&css_set_rwsem);
+}
 
 static void init_cgroup_housekeeping(struct cgroup *cgrp)
 {
+	atomic_set(&cgrp->refcnt, 1);
 	INIT_LIST_HEAD(&cgrp->sibling);
 	INIT_LIST_HEAD(&cgrp->children);
-	INIT_LIST_HEAD(&cgrp->files);
 	INIT_LIST_HEAD(&cgrp->cset_links);
 	INIT_LIST_HEAD(&cgrp->release_list);
 	INIT_LIST_HEAD(&cgrp->pidlists);
 	mutex_init(&cgrp->pidlist_mutex);
 	cgrp->dummy_css.cgroup = cgrp;
-	simple_xattrs_init(&cgrp->xattrs);
 }
 
-static void init_cgroup_root(struct cgroupfs_root *root)
+static void init_cgroup_root(struct cgroup_root *root,
+			     struct cgroup_sb_opts *opts)
 {
-	struct cgroup *cgrp = &root->top_cgroup;
+	struct cgroup *cgrp = &root->cgrp;
 
 	INIT_LIST_HEAD(&root->root_list);
-	root->number_of_cgroups = 1;
+	atomic_set(&root->nr_cgrps, 1);
 	cgrp->root = root;
-	RCU_INIT_POINTER(cgrp->name, &root_cgroup_name);
 	init_cgroup_housekeeping(cgrp);
 	idr_init(&root->cgroup_idr);
-}
-
-static int cgroup_init_root_id(struct cgroupfs_root *root, int start, int end)
-{
-	int id;
-
-	lockdep_assert_held(&cgroup_mutex);
-	lockdep_assert_held(&cgroup_root_mutex);
-
-	id = idr_alloc_cyclic(&cgroup_hierarchy_idr, root, start, end,
-			      GFP_KERNEL);
-	if (id < 0)
-		return id;
-
-	root->hierarchy_id = id;
-	return 0;
-}
-
-static void cgroup_exit_root_id(struct cgroupfs_root *root)
-{
-	lockdep_assert_held(&cgroup_mutex);
-	lockdep_assert_held(&cgroup_root_mutex);
-
-	if (root->hierarchy_id) {
-		idr_remove(&cgroup_hierarchy_idr, root->hierarchy_id);
-		root->hierarchy_id = 0;
-	}
-}
-
-static int cgroup_test_super(struct super_block *sb, void *data)
-{
-	struct cgroup_sb_opts *opts = data;
-	struct cgroupfs_root *root = sb->s_fs_info;
-
-	/* If we asked for a name then it must match */
-	if (opts->name && strcmp(opts->name, root->name))
-		return 0;
-
-	/*
-	 * If we asked for subsystems (or explicitly for no
-	 * subsystems) then they must match
-	 */
-	if ((opts->subsys_mask || opts->none)
-	    && (opts->subsys_mask != root->subsys_mask))
-		return 0;
-
-	return 1;
-}
-
-static struct cgroupfs_root *cgroup_root_from_opts(struct cgroup_sb_opts *opts)
-{
-	struct cgroupfs_root *root;
 
-	if (!opts->subsys_mask && !opts->none)
-		return NULL;
-
-	root = kzalloc(sizeof(*root), GFP_KERNEL);
-	if (!root)
-		return ERR_PTR(-ENOMEM);
-
-	init_cgroup_root(root);
-
-	/*
-	 * We need to set @root->subsys_mask now so that @root can be
-	 * matched by cgroup_test_super() before it finishes
-	 * initialization; otherwise, competing mounts with the same
-	 * options may try to bind the same subsystems instead of waiting
-	 * for the first one leading to unexpected mount errors.
-	 * SUBSYS_BOUND will be set once actual binding is complete.
-	 */
-	root->subsys_mask = opts->subsys_mask;
 	root->flags = opts->flags;
 	if (opts->release_agent)
 		strcpy(root->release_agent_path, opts->release_agent);
 	if (opts->name)
 		strcpy(root->name, opts->name);
 	if (opts->cpuset_clone_children)
-		set_bit(CGRP_CPUSET_CLONE_CHILDREN, &root->top_cgroup.flags);
-	return root;
+		set_bit(CGRP_CPUSET_CLONE_CHILDREN, &root->cgrp.flags);
 }
 
-static void cgroup_free_root(struct cgroupfs_root *root)
+static int cgroup_setup_root(struct cgroup_root *root, unsigned long ss_mask)
 {
-	if (root) {
-		/* hierarhcy ID shoulid already have been released */
-		WARN_ON_ONCE(root->hierarchy_id);
-
-		idr_destroy(&root->cgroup_idr);
-		kfree(root);
-	}
-}
+	LIST_HEAD(tmp_links);
+	struct cgroup *root_cgrp = &root->cgrp;
+	struct css_set *cset;
+	int i, ret;
 
-static int cgroup_set_super(struct super_block *sb, void *data)
-{
-	int ret;
-	struct cgroup_sb_opts *opts = data;
+	lockdep_assert_held(&cgroup_tree_mutex);
+	lockdep_assert_held(&cgroup_mutex);
 
-	/* If we don't have a new root, we can't set up a new sb */
-	if (!opts->new_root)
-		return -EINVAL;
+	ret = idr_alloc(&root->cgroup_idr, root_cgrp, 0, 1, GFP_KERNEL);
+	if (ret < 0)
+		goto out;
+	root_cgrp->id = ret;
 
-	BUG_ON(!opts->subsys_mask && !opts->none);
+	/*
+	 * We're accessing css_set_count without locking css_set_rwsem here,
+	 * but that's OK - it can only be increased by someone holding
+	 * cgroup_lock, and that's us. The worst that can happen is that we
+	 * have some link structures left over
+	 */
+	ret = allocate_cgrp_cset_links(css_set_count, &tmp_links);
+	if (ret)
+		goto out;
 
-	ret = set_anon_super(sb, NULL);
+	ret = cgroup_init_root_id(root);
 	if (ret)
-		return ret;
+		goto out;
 
-	sb->s_fs_info = opts->new_root;
-	opts->new_root->sb = sb;
+	root->kf_root = kernfs_create_root(&cgroup_kf_syscall_ops,
+					   KERNFS_ROOT_CREATE_DEACTIVATED,
+					   root_cgrp);
+	if (IS_ERR(root->kf_root)) {
+		ret = PTR_ERR(root->kf_root);
+		goto exit_root_id;
+	}
+	root_cgrp->kn = root->kf_root->kn;
 
-	sb->s_blocksize = PAGE_CACHE_SIZE;
-	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
-	sb->s_magic = CGROUP_SUPER_MAGIC;
-	sb->s_op = &cgroup_ops;
+	ret = cgroup_addrm_files(root_cgrp, cgroup_base_files, true);
+	if (ret)
+		goto destroy_root;
 
-	return 0;
-}
+	ret = rebind_subsystems(root, ss_mask);
+	if (ret)
+		goto destroy_root;
 
-static int cgroup_get_rootdir(struct super_block *sb)
-{
-	static const struct dentry_operations cgroup_dops = {
-		.d_iput = cgroup_diput,
-		.d_delete = always_delete_dentry,
-	};
+	/*
+	 * There must be no failure case after here, since rebinding takes
+	 * care of subsystems' refcounts, which are explicitly dropped in
+	 * the failure exit path.
+	 */
+	list_add(&root->root_list, &cgroup_roots);
+	cgroup_root_count++;
 
-	struct inode *inode =
-		cgroup_new_inode(S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR, sb);
+	/*
+	 * Link the root cgroup in this hierarchy into all the css_set
+	 * objects.
+	 */
+	down_write(&css_set_rwsem);
+	hash_for_each(css_set_table, i, cset, hlist)
+		link_css_set(&tmp_links, cset, root_cgrp);
+	up_write(&css_set_rwsem);
 
-	if (!inode)
-		return -ENOMEM;
+	BUG_ON(!list_empty(&root_cgrp->children));
+	BUG_ON(atomic_read(&root->nr_cgrps) != 1);
 
-	inode->i_fop = &simple_dir_operations;
-	inode->i_op = &cgroup_dir_inode_operations;
-	/* directories start off with i_nlink == 2 (for "." entry) */
-	inc_nlink(inode);
-	sb->s_root = d_make_root(inode);
-	if (!sb->s_root)
-		return -ENOMEM;
-	/* for everything else we want ->d_op set */
-	sb->s_d_op = &cgroup_dops;
-	return 0;
+	kernfs_activate(root_cgrp->kn);
+	ret = 0;
+	goto out;
+
+destroy_root:
+	kernfs_destroy_root(root->kf_root);
+	root->kf_root = NULL;
+exit_root_id:
+	cgroup_exit_root_id(root);
+out:
+	free_cgrp_cset_links(&tmp_links);
+	return ret;
 }
 
 static struct dentry *cgroup_mount(struct file_system_type *fs_type,
 			 int flags, const char *unused_dev_name,
 			 void *data)
 {
+	struct cgroup_root *root;
 	struct cgroup_sb_opts opts;
-	struct cgroupfs_root *root;
-	int ret = 0;
-	struct super_block *sb;
-	struct cgroupfs_root *new_root;
-	struct list_head tmp_links;
-	struct inode *inode;
-	const struct cred *cred;
-
-	/* First find the desired set of subsystems */
-	mutex_lock(&cgroup_mutex);
-	ret = parse_cgroupfs_options(data, &opts);
-	mutex_unlock(&cgroup_mutex);
-	if (ret)
-		goto out_err;
+	struct dentry *dentry;
+	int ret;
+	bool new_sb;
 
 	/*
-	 * Allocate a new cgroup root. We may not need it if we're
-	 * reusing an existing hierarchy.
+	 * The first time anyone tries to mount a cgroup, enable the list
+	 * linking each css_set to its tasks and fix up all existing tasks.
 	 */
-	new_root = cgroup_root_from_opts(&opts);
-	if (IS_ERR(new_root)) {
-		ret = PTR_ERR(new_root);
-		goto out_err;
-	}
-	opts.new_root = new_root;
-
-	/* Locate an existing or new sb for this hierarchy */
-	sb = sget(fs_type, cgroup_test_super, cgroup_set_super, 0, &opts);
-	if (IS_ERR(sb)) {
-		ret = PTR_ERR(sb);
-		cgroup_free_root(opts.new_root);
-		goto out_err;
-	}
-
-	root = sb->s_fs_info;
-	BUG_ON(!root);
-	if (root == opts.new_root) {
-		/* We used the new root structure, so this is a new hierarchy */
-		struct cgroup *root_cgrp = &root->top_cgroup;
-		struct cgroupfs_root *existing_root;
-		int i;
-		struct css_set *cset;
-
-		BUG_ON(sb->s_root != NULL);
-
-		ret = cgroup_get_rootdir(sb);
-		if (ret)
-			goto drop_new_super;
-		inode = sb->s_root->d_inode;
-
-		mutex_lock(&inode->i_mutex);
-		mutex_lock(&cgroup_mutex);
-		mutex_lock(&cgroup_root_mutex);
-
-		ret = idr_alloc(&root->cgroup_idr, root_cgrp, 0, 1, GFP_KERNEL);
-		if (ret < 0)
-			goto unlock_drop;
-		root_cgrp->id = ret;
-
-		/* Check for name clashes with existing mounts */
-		ret = -EBUSY;
-		if (strlen(root->name))
-			for_each_active_root(existing_root)
-				if (!strcmp(existing_root->name, root->name))
-					goto unlock_drop;
-
-		/*
-		 * We're accessing css_set_count without locking
-		 * css_set_lock here, but that's OK - it can only be
-		 * increased by someone holding cgroup_lock, and
-		 * that's us. The worst that can happen is that we
-		 * have some link structures left over
-		 */
-		ret = allocate_cgrp_cset_links(css_set_count, &tmp_links);
-		if (ret)
-			goto unlock_drop;
-
-		/* ID 0 is reserved for dummy root, 1 for unified hierarchy */
-		ret = cgroup_init_root_id(root, 2, 0);
-		if (ret)
-			goto unlock_drop;
-
-		sb->s_root->d_fsdata = root_cgrp;
-		root_cgrp->dentry = sb->s_root;
+	if (!use_task_css_set_links)
+		cgroup_enable_task_cg_lists();
 
-		/*
-		 * We're inside get_sb() and will call lookup_one_len() to
-		 * create the root files, which doesn't work if SELinux is
-		 * in use.  The following cred dancing somehow works around
-		 * it.  See 2ce9738ba ("cgroupfs: use init_cred when
-		 * populating new cgroupfs mount") for more details.
-		 */
-		cred = override_creds(&init_cred);
+	mutex_lock(&cgroup_tree_mutex);
+	mutex_lock(&cgroup_mutex);
 
-		ret = cgroup_addrm_files(root_cgrp, cgroup_base_files, true);
-		if (ret)
-			goto rm_base_files;
+	/* First find the desired set of subsystems */
+	ret = parse_cgroupfs_options(data, &opts);
+	if (ret)
+		goto out_unlock;
+retry:
+	/* look for a matching existing root */
+	if (!opts.subsys_mask && !opts.none && !opts.name) {
+		cgrp_dfl_root_visible = true;
+		root = &cgrp_dfl_root;
+		cgroup_get(&root->cgrp);
+		ret = 0;
+		goto out_unlock;
+	}
 
-		ret = rebind_subsystems(root, root->subsys_mask, 0);
-		if (ret)
-			goto rm_base_files;
+	for_each_root(root) {
+		bool name_match = false;
 
-		revert_creds(cred);
+		if (root == &cgrp_dfl_root)
+			continue;
 
 		/*
-		 * There must be no failure case after here, since rebinding
-		 * takes care of subsystems' refcounts, which are explicitly
-		 * dropped in the failure exit path.
+		 * If we asked for a name then it must match.  Also, if
+		 * name matches but sybsys_mask doesn't, we should fail.
+		 * Remember whether name matched.
 		 */
+		if (opts.name) {
+			if (strcmp(opts.name, root->name))
+				continue;
+			name_match = true;
+		}
 
-		list_add(&root->root_list, &cgroup_roots);
-		cgroup_root_count++;
-
-		/* Link the top cgroup in this hierarchy into all
-		 * the css_set objects */
-		write_lock(&css_set_lock);
-		hash_for_each(css_set_table, i, cset, hlist)
-			link_css_set(&tmp_links, cset, root_cgrp);
-		write_unlock(&css_set_lock);
-
-		free_cgrp_cset_links(&tmp_links);
-
-		BUG_ON(!list_empty(&root_cgrp->children));
-		BUG_ON(root->number_of_cgroups != 1);
-
-		mutex_unlock(&cgroup_root_mutex);
-		mutex_unlock(&cgroup_mutex);
-		mutex_unlock(&inode->i_mutex);
-	} else {
 		/*
-		 * We re-used an existing hierarchy - the new root (if
-		 * any) is not needed
+		 * If we asked for subsystems (or explicitly for no
+		 * subsystems) then they must match.
 		 */
-		cgroup_free_root(opts.new_root);
+		if ((opts.subsys_mask || opts.none) &&
+		    (opts.subsys_mask != root->cgrp.subsys_mask)) {
+			if (!name_match)
+				continue;
+			ret = -EBUSY;
+			goto out_unlock;
+		}
 
 		if ((root->flags ^ opts.flags) & CGRP_ROOT_OPTION_MASK) {
 			if ((root->flags | opts.flags) & CGRP_ROOT_SANE_BEHAVIOR) {
 				pr_err("cgroup: sane_behavior: new mount options should match the existing superblock\n");
 				ret = -EINVAL;
-				goto drop_new_super;
+				goto out_unlock;
 			} else {
 				pr_warning("cgroup: new mount options do not match the existing superblock, will be ignored\n");
 			}
 		}
-	}
 
-	kfree(opts.release_agent);
-	kfree(opts.name);
-	return dget(sb->s_root);
-
- rm_base_files:
-	free_cgrp_cset_links(&tmp_links);
-	cgroup_addrm_files(&root->top_cgroup, cgroup_base_files, false);
-	revert_creds(cred);
- unlock_drop:
-	cgroup_exit_root_id(root);
-	mutex_unlock(&cgroup_root_mutex);
-	mutex_unlock(&cgroup_mutex);
-	mutex_unlock(&inode->i_mutex);
- drop_new_super:
-	deactivate_locked_super(sb);
- out_err:
-	kfree(opts.release_agent);
-	kfree(opts.name);
-	return ERR_PTR(ret);
-}
-
-static void cgroup_kill_sb(struct super_block *sb)
-{
-	struct cgroupfs_root *root = sb->s_fs_info;
-	struct cgroup *cgrp = &root->top_cgroup;
-	struct cgrp_cset_link *link, *tmp_link;
-	int ret;
-
-	BUG_ON(!root);
-
-	BUG_ON(root->number_of_cgroups != 1);
-	BUG_ON(!list_empty(&cgrp->children));
-
-	mutex_lock(&cgrp->dentry->d_inode->i_mutex);
-	mutex_lock(&cgroup_mutex);
-	mutex_lock(&cgroup_root_mutex);
+		/*
+		 * A root's lifetime is governed by its root cgroup.  Zero
+		 * ref indicate that the root is being destroyed.  Wait for
+		 * destruction to complete so that the subsystems are free.
+		 * We can use wait_queue for the wait but this path is
+		 * super cold.  Let's just sleep for a bit and retry.
+		 */
+		if (!atomic_inc_not_zero(&root->cgrp.refcnt)) {
+			mutex_unlock(&cgroup_mutex);
+			mutex_unlock(&cgroup_tree_mutex);
+			msleep(10);
+			mutex_lock(&cgroup_tree_mutex);
+			mutex_lock(&cgroup_mutex);
+			goto retry;
+		}
 
-	/* Rebind all subsystems back to the default hierarchy */
-	if (root->flags & CGRP_ROOT_SUBSYS_BOUND) {
-		ret = rebind_subsystems(root, 0, root->subsys_mask);
-		/* Shouldn't be able to fail ... */
-		BUG_ON(ret);
+		ret = 0;
+		goto out_unlock;
 	}
 
 	/*
-	 * Release all the links from cset_links to this hierarchy's
-	 * root cgroup
+	 * No such thing, create a new one.  name= matching without subsys
+	 * specification is allowed for already existing hierarchies but we
+	 * can't create new one without subsys specification.
 	 */
-	write_lock(&css_set_lock);
-
-	list_for_each_entry_safe(link, tmp_link, &cgrp->cset_links, cset_link) {
-		list_del(&link->cset_link);
-		list_del(&link->cgrp_link);
-		kfree(link);
+	if (!opts.subsys_mask && !opts.none) {
+		ret = -EINVAL;
+		goto out_unlock;
 	}
-	write_unlock(&css_set_lock);
 
-	if (!list_empty(&root->root_list)) {
-		list_del(&root->root_list);
-		cgroup_root_count--;
+	root = kzalloc(sizeof(*root), GFP_KERNEL);
+	if (!root) {
+		ret = -ENOMEM;
+		goto out_unlock;
 	}
 
-	cgroup_exit_root_id(root);
+	init_cgroup_root(root, &opts);
 
-	mutex_unlock(&cgroup_root_mutex);
+	ret = cgroup_setup_root(root, opts.subsys_mask);
+	if (ret)
+		cgroup_free_root(root);
+
+out_unlock:
 	mutex_unlock(&cgroup_mutex);
-	mutex_unlock(&cgrp->dentry->d_inode->i_mutex);
+	mutex_unlock(&cgroup_tree_mutex);
 
-	simple_xattrs_free(&cgrp->xattrs);
+	kfree(opts.release_agent);
+	kfree(opts.name);
 
-	kill_litter_super(sb);
-	cgroup_free_root(root);
+	if (ret)
+		return ERR_PTR(ret);
+
+	dentry = kernfs_mount(fs_type, flags, root->kf_root,
+				CGROUP_SUPER_MAGIC, &new_sb);
+	if (IS_ERR(dentry) || !new_sb)
+		cgroup_put(&root->cgrp);
+	return dentry;
+}
+
+static void cgroup_kill_sb(struct super_block *sb)
+{
+	struct kernfs_root *kf_root = kernfs_root_from_sb(sb);
+	struct cgroup_root *root = cgroup_root_from_kf(kf_root);
+
+	cgroup_put(&root->cgrp);
+	kernfs_kill_sb(sb);
 }
 
 static struct file_system_type cgroup_fs_type = {
@@ -1743,57 +1630,6 @@ static struct file_system_type cgroup_fs_type = {
 static struct kobject *cgroup_kobj;
 
 /**
- * cgroup_path - generate the path of a cgroup
- * @cgrp: the cgroup in question
- * @buf: the buffer to write the path into
- * @buflen: the length of the buffer
- *
- * Writes path of cgroup into buf.  Returns 0 on success, -errno on error.
- *
- * We can't generate cgroup path using dentry->d_name, as accessing
- * dentry->name must be protected by irq-unsafe dentry->d_lock or parent
- * inode's i_mutex, while on the other hand cgroup_path() can be called
- * with some irq-safe spinlocks held.
- */
-int cgroup_path(const struct cgroup *cgrp, char *buf, int buflen)
-{
-	int ret = -ENAMETOOLONG;
-	char *start;
-
-	if (!cgrp->parent) {
-		if (strlcpy(buf, "/", buflen) >= buflen)
-			return -ENAMETOOLONG;
-		return 0;
-	}
-
-	start = buf + buflen - 1;
-	*start = '\0';
-
-	rcu_read_lock();
-	do {
-		const char *name = cgroup_name(cgrp);
-		int len;
-
-		len = strlen(name);
-		if ((start -= len) < buf)
-			goto out;
-		memcpy(start, name, len);
-
-		if (--start < buf)
-			goto out;
-		*start = '/';
-
-		cgrp = cgrp->parent;
-	} while (cgrp->parent);
-	ret = 0;
-	memmove(buf, start, buf + buflen - start);
-out:
-	rcu_read_unlock();
-	return ret;
-}
-EXPORT_SYMBOL_GPL(cgroup_path);
-
-/**
  * task_cgroup_path - cgroup path of a task in the first cgroup hierarchy
  * @task: target task
  * @buf: the buffer to write the path into
@@ -1804,49 +1640,55 @@ EXPORT_SYMBOL_GPL(cgroup_path);
  * function grabs cgroup_mutex and shouldn't be used inside locks used by
  * cgroup controller callbacks.
  *
- * Returns 0 on success, fails with -%ENAMETOOLONG if @buflen is too short.
+ * Return value is the same as kernfs_path().
  */
-int task_cgroup_path(struct task_struct *task, char *buf, size_t buflen)
+char *task_cgroup_path(struct task_struct *task, char *buf, size_t buflen)
 {
-	struct cgroupfs_root *root;
+	struct cgroup_root *root;
 	struct cgroup *cgrp;
-	int hierarchy_id = 1, ret = 0;
-
-	if (buflen < 2)
-		return -ENAMETOOLONG;
+	int hierarchy_id = 1;
+	char *path = NULL;
 
 	mutex_lock(&cgroup_mutex);
+	down_read(&css_set_rwsem);
 
 	root = idr_get_next(&cgroup_hierarchy_idr, &hierarchy_id);
 
 	if (root) {
 		cgrp = task_cgroup_from_root(task, root);
-		ret = cgroup_path(cgrp, buf, buflen);
+		path = cgroup_path(cgrp, buf, buflen);
 	} else {
 		/* if no hierarchy exists, everyone is in "/" */
-		memcpy(buf, "/", 2);
+		if (strlcpy(buf, "/", buflen) < buflen)
+			path = buf;
 	}
 
+	up_read(&css_set_rwsem);
 	mutex_unlock(&cgroup_mutex);
-	return ret;
+	return path;
 }
 EXPORT_SYMBOL_GPL(task_cgroup_path);
 
-/*
- * Control Group taskset
- */
-struct task_and_cgroup {
-	struct task_struct	*task;
-	struct cgroup		*cgrp;
-	struct css_set		*cset;
-};
-
+/* used to track tasks and other necessary states during migration */
 struct cgroup_taskset {
-	struct task_and_cgroup	single;
-	struct flex_array	*tc_array;
-	int			tc_array_len;
-	int			idx;
-	struct cgroup		*cur_cgrp;
+	/* the src and dst cset list running through cset->mg_node */
+	struct list_head	src_csets;
+	struct list_head	dst_csets;
+
+	/*
+	 * Fields for cgroup_taskset_*() iteration.
+	 *
+	 * Before migration is committed, the target migration tasks are on
+	 * ->mg_tasks of the csets on ->src_csets.  After, on ->mg_tasks of
+	 * the csets on ->dst_csets.  ->csets point to either ->src_csets
+	 * or ->dst_csets depending on whether migration is committed.
+	 *
+	 * ->cur_csets and ->cur_task point to the current task position
+	 * during iteration.
+	 */
+	struct list_head	*csets;
+	struct css_set		*cur_cset;
+	struct task_struct	*cur_task;
 };
 
 /**
@@ -1857,15 +1699,11 @@ struct cgroup_taskset {
  */
 struct task_struct *cgroup_taskset_first(struct cgroup_taskset *tset)
 {
-	if (tset->tc_array) {
-		tset->idx = 0;
-		return cgroup_taskset_next(tset);
-	} else {
-		tset->cur_cgrp = tset->single.cgrp;
-		return tset->single.task;
-	}
+	tset->cur_cset = list_first_entry(tset->csets, struct css_set, mg_node);
+	tset->cur_task = NULL;
+
+	return cgroup_taskset_next(tset);
 }
-EXPORT_SYMBOL_GPL(cgroup_taskset_first);
 
 /**
  * cgroup_taskset_next - iterate to the next task in taskset
@@ -1876,48 +1714,36 @@ EXPORT_SYMBOL_GPL(cgroup_taskset_first);
  */
 struct task_struct *cgroup_taskset_next(struct cgroup_taskset *tset)
 {
-	struct task_and_cgroup *tc;
+	struct css_set *cset = tset->cur_cset;
+	struct task_struct *task = tset->cur_task;
 
-	if (!tset->tc_array || tset->idx >= tset->tc_array_len)
-		return NULL;
+	while (&cset->mg_node != tset->csets) {
+		if (!task)
+			task = list_first_entry(&cset->mg_tasks,
+						struct task_struct, cg_list);
+		else
+			task = list_next_entry(task, cg_list);
 
-	tc = flex_array_get(tset->tc_array, tset->idx++);
-	tset->cur_cgrp = tc->cgrp;
-	return tc->task;
-}
-EXPORT_SYMBOL_GPL(cgroup_taskset_next);
+		if (&task->cg_list != &cset->mg_tasks) {
+			tset->cur_cset = cset;
+			tset->cur_task = task;
+			return task;
+		}
 
-/**
- * cgroup_taskset_cur_css - return the matching css for the current task
- * @tset: taskset of interest
- * @subsys_id: the ID of the target subsystem
- *
- * Return the css for the current (last returned) task of @tset for
- * subsystem specified by @subsys_id.  This function must be preceded by
- * either cgroup_taskset_first() or cgroup_taskset_next().
- */
-struct cgroup_subsys_state *cgroup_taskset_cur_css(struct cgroup_taskset *tset,
-						   int subsys_id)
-{
-	return cgroup_css(tset->cur_cgrp, cgroup_subsys[subsys_id]);
-}
-EXPORT_SYMBOL_GPL(cgroup_taskset_cur_css);
+		cset = list_next_entry(cset, mg_node);
+		task = NULL;
+	}
 
-/**
- * cgroup_taskset_size - return the number of tasks in taskset
- * @tset: taskset of interest
- */
-int cgroup_taskset_size(struct cgroup_taskset *tset)
-{
-	return tset->tc_array ? tset->tc_array_len : 1;
+	return NULL;
 }
-EXPORT_SYMBOL_GPL(cgroup_taskset_size);
-
 
-/*
+/**
  * cgroup_task_migrate - move a task from one cgroup to another.
+ * @old_cgrp; the cgroup @tsk is being migrated from
+ * @tsk: the task being migrated
+ * @new_cset: the new css_set @tsk is being attached to
  *
- * Must be called with cgroup_mutex and threadgroup locked.
+ * Must be called with cgroup_mutex, threadgroup and css_set_rwsem locked.
  */
 static void cgroup_task_migrate(struct cgroup *old_cgrp,
 				struct task_struct *tsk,
@@ -1925,6 +1751,9 @@ static void cgroup_task_migrate(struct cgroup *old_cgrp,
 {
 	struct css_set *old_cset;
 
+	lockdep_assert_held(&cgroup_mutex);
+	lockdep_assert_held(&css_set_rwsem);
+
 	/*
 	 * We are synchronized through threadgroup_lock() against PF_EXITING
 	 * setting such that we can't race against cgroup_exit() changing the
@@ -1933,15 +1762,16 @@ static void cgroup_task_migrate(struct cgroup *old_cgrp,
 	WARN_ON_ONCE(tsk->flags & PF_EXITING);
 	old_cset = task_css_set(tsk);
 
-	task_lock(tsk);
+	get_css_set(new_cset);
 	rcu_assign_pointer(tsk->cgroups, new_cset);
-	task_unlock(tsk);
 
-	/* Update the css_set linked lists if we're using them */
-	write_lock(&css_set_lock);
-	if (!list_empty(&tsk->cg_list))
-		list_move(&tsk->cg_list, &new_cset->tasks);
-	write_unlock(&css_set_lock);
+	/*
+	 * Use move_tail so that cgroup_taskset_first() still returns the
+	 * leader after migration.  This works because cgroup_migrate()
+	 * ensures that the dst_cset of the leader is the first on the
+	 * tset's dst_csets list.
+	 */
+	list_move_tail(&tsk->cg_list, &new_cset->mg_tasks);
 
 	/*
 	 * We just gained a reference on old_cset by taking it from the
@@ -1949,100 +1779,199 @@ static void cgroup_task_migrate(struct cgroup *old_cgrp,
 	 * we're safe to drop it here; it will be freed under RCU.
 	 */
 	set_bit(CGRP_RELEASABLE, &old_cgrp->flags);
-	put_css_set(old_cset);
+	put_css_set_locked(old_cset, false);
 }
 
 /**
- * cgroup_attach_task - attach a task or a whole threadgroup to a cgroup
- * @cgrp: the cgroup to attach to
- * @tsk: the task or the leader of the threadgroup to be attached
- * @threadgroup: attach the whole threadgroup?
+ * cgroup_migrate_finish - cleanup after attach
+ * @preloaded_csets: list of preloaded css_sets
  *
- * Call holding cgroup_mutex and the group_rwsem of the leader. Will take
- * task_lock of @tsk or each thread in the threadgroup individually in turn.
+ * Undo cgroup_migrate_add_src() and cgroup_migrate_prepare_dst().  See
+ * those functions for details.
  */
-static int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk,
-			      bool threadgroup)
+static void cgroup_migrate_finish(struct list_head *preloaded_csets)
 {
-	int retval, i, group_size;
-	struct cgroupfs_root *root = cgrp->root;
-	struct cgroup_subsys_state *css, *failed_css = NULL;
-	/* threadgroup list cursor and array */
-	struct task_struct *leader = tsk;
-	struct task_and_cgroup *tc;
-	struct flex_array *group;
-	struct cgroup_taskset tset = { };
+	struct css_set *cset, *tmp_cset;
 
-	/*
-	 * step 0: in order to do expensive, possibly blocking operations for
-	 * every thread, we cannot iterate the thread group list, since it needs
-	 * rcu or tasklist locked. instead, build an array of all threads in the
-	 * group - group_rwsem prevents new threads from appearing, and if
-	 * threads exit, this will just be an over-estimate.
-	 */
-	if (threadgroup)
-		group_size = get_nr_threads(tsk);
-	else
-		group_size = 1;
-	/* flex_array supports very large thread-groups better than kmalloc. */
-	group = flex_array_alloc(sizeof(*tc), group_size, GFP_KERNEL);
-	if (!group)
-		return -ENOMEM;
-	/* pre-allocate to guarantee space while iterating in rcu read-side. */
-	retval = flex_array_prealloc(group, 0, group_size, GFP_KERNEL);
-	if (retval)
-		goto out_free_group_list;
+	lockdep_assert_held(&cgroup_mutex);
+
+	down_write(&css_set_rwsem);
+	list_for_each_entry_safe(cset, tmp_cset, preloaded_csets, mg_preload_node) {
+		cset->mg_src_cgrp = NULL;
+		cset->mg_dst_cset = NULL;
+		list_del_init(&cset->mg_preload_node);
+		put_css_set_locked(cset, false);
+	}
+	up_write(&css_set_rwsem);
+}
+
+/**
+ * cgroup_migrate_add_src - add a migration source css_set
+ * @src_cset: the source css_set to add
+ * @dst_cgrp: the destination cgroup
+ * @preloaded_csets: list of preloaded css_sets
+ *
+ * Tasks belonging to @src_cset are about to be migrated to @dst_cgrp.  Pin
+ * @src_cset and add it to @preloaded_csets, which should later be cleaned
+ * up by cgroup_migrate_finish().
+ *
+ * This function may be called without holding threadgroup_lock even if the
+ * target is a process.  Threads may be created and destroyed but as long
+ * as cgroup_mutex is not dropped, no new css_set can be put into play and
+ * the preloaded css_sets are guaranteed to cover all migrations.
+ */
+static void cgroup_migrate_add_src(struct css_set *src_cset,
+				   struct cgroup *dst_cgrp,
+				   struct list_head *preloaded_csets)
+{
+	struct cgroup *src_cgrp;
+
+	lockdep_assert_held(&cgroup_mutex);
+	lockdep_assert_held(&css_set_rwsem);
+
+	src_cgrp = cset_cgroup_from_root(src_cset, dst_cgrp->root);
+
+	/* nothing to do if this cset already belongs to the cgroup */
+	if (src_cgrp == dst_cgrp)
+		return;
+
+	if (!list_empty(&src_cset->mg_preload_node))
+		return;
+
+	WARN_ON(src_cset->mg_src_cgrp);
+	WARN_ON(!list_empty(&src_cset->mg_tasks));
+	WARN_ON(!list_empty(&src_cset->mg_node));
+
+	src_cset->mg_src_cgrp = src_cgrp;
+	get_css_set(src_cset);
+	list_add(&src_cset->mg_preload_node, preloaded_csets);
+}
+
+/**
+ * cgroup_migrate_prepare_dst - prepare destination css_sets for migration
+ * @dst_cgrp: the destination cgroup
+ * @preloaded_csets: list of preloaded source css_sets
+ *
+ * Tasks are about to be moved to @dst_cgrp and all the source css_sets
+ * have been preloaded to @preloaded_csets.  This function looks up and
+ * pins all destination css_sets, links each to its source, and put them on
+ * @preloaded_csets.
+ *
+ * This function must be called after cgroup_migrate_add_src() has been
+ * called on each migration source css_set.  After migration is performed
+ * using cgroup_migrate(), cgroup_migrate_finish() must be called on
+ * @preloaded_csets.
+ */
+static int cgroup_migrate_prepare_dst(struct cgroup *dst_cgrp,
+				      struct list_head *preloaded_csets)
+{
+	LIST_HEAD(csets);
+	struct css_set *src_cset;
+
+	lockdep_assert_held(&cgroup_mutex);
+
+	/* look up the dst cset for each src cset and link it to src */
+	list_for_each_entry(src_cset, preloaded_csets, mg_preload_node) {
+		struct css_set *dst_cset;
+
+		dst_cset = find_css_set(src_cset, dst_cgrp);
+		if (!dst_cset)
+			goto err;
+
+		WARN_ON_ONCE(src_cset->mg_dst_cset || dst_cset->mg_dst_cset);
+		src_cset->mg_dst_cset = dst_cset;
+
+		if (list_empty(&dst_cset->mg_preload_node))
+			list_add(&dst_cset->mg_preload_node, &csets);
+		else
+			put_css_set(dst_cset, false);
+	}
+
+	list_splice(&csets, preloaded_csets);
+	return 0;
+err:
+	cgroup_migrate_finish(&csets);
+	return -ENOMEM;
+}
+
+/**
+ * cgroup_migrate - migrate a process or task to a cgroup
+ * @cgrp: the destination cgroup
+ * @leader: the leader of the process or the task to migrate
+ * @threadgroup: whether @leader points to the whole process or a single task
+ *
+ * Migrate a process or task denoted by @leader to @cgrp.  If migrating a
+ * process, the caller must be holding threadgroup_lock of @leader.  The
+ * caller is also responsible for invoking cgroup_migrate_add_src() and
+ * cgroup_migrate_prepare_dst() on the targets before invoking this
+ * function and following up with cgroup_migrate_finish().
+ *
+ * As long as a controller's ->can_attach() doesn't fail, this function is
+ * guaranteed to succeed.  This means that, excluding ->can_attach()
+ * failure, when migrating multiple targets, the success or failure can be
+ * decided for all targets by invoking group_migrate_prepare_dst() before
+ * actually starting migrating.
+ */
+static int cgroup_migrate(struct cgroup *cgrp, struct task_struct *leader,
+			  bool threadgroup)
+{
+	struct cgroup_taskset tset = {
+		.src_csets	= LIST_HEAD_INIT(tset.src_csets),
+		.dst_csets	= LIST_HEAD_INIT(tset.dst_csets),
+		.csets		= &tset.src_csets,
+	};
+	struct cgroup_subsys_state *css, *failed_css = NULL;
+	struct css_set *cset, *tmp_cset;
+	struct task_struct *task, *tmp_task;
+	int i, ret;
 
-	i = 0;
 	/*
 	 * Prevent freeing of tasks while we take a snapshot. Tasks that are
 	 * already PF_EXITING could be freed from underneath us unless we
 	 * take an rcu_read_lock.
 	 */
+	down_write(&css_set_rwsem);
 	rcu_read_lock();
+	task = leader;
 	do {
-		struct task_and_cgroup ent;
+		/* @task either already exited or can't exit until the end */
+		if (task->flags & PF_EXITING)
+			goto next;
 
-		/* @tsk either already exited or can't exit until the end */
-		if (tsk->flags & PF_EXITING)
+		/* leave @task alone if post_fork() hasn't linked it yet */
+		if (list_empty(&task->cg_list))
 			goto next;
 
-		/* as per above, nr_threads may decrease, but not increase. */
-		BUG_ON(i >= group_size);
-		ent.task = tsk;
-		ent.cgrp = task_cgroup_from_root(tsk, root);
-		/* nothing to do if this task is already in the cgroup */
-		if (ent.cgrp == cgrp)
+		cset = task_css_set(task);
+		if (!cset->mg_src_cgrp)
 			goto next;
+
 		/*
-		 * saying GFP_ATOMIC has no effect here because we did prealloc
-		 * earlier, but it's good form to communicate our expectations.
+		 * cgroup_taskset_first() must always return the leader.
+		 * Take care to avoid disturbing the ordering.
 		 */
-		retval = flex_array_put(group, i, &ent, GFP_ATOMIC);
-		BUG_ON(retval != 0);
-		i++;
+		list_move_tail(&task->cg_list, &cset->mg_tasks);
+		if (list_empty(&cset->mg_node))
+			list_add_tail(&cset->mg_node, &tset.src_csets);
+		if (list_empty(&cset->mg_dst_cset->mg_node))
+			list_move_tail(&cset->mg_dst_cset->mg_node,
+				       &tset.dst_csets);
 	next:
 		if (!threadgroup)
 			break;
-	} while_each_thread(leader, tsk);
+	} while_each_thread(leader, task);
 	rcu_read_unlock();
-	/* remember the number of threads in the array for later. */
-	group_size = i;
-	tset.tc_array = group;
-	tset.tc_array_len = group_size;
+	up_write(&css_set_rwsem);
 
 	/* methods shouldn't be called if no task is actually migrating */
-	retval = 0;
-	if (!group_size)
-		goto out_free_group_list;
+	if (list_empty(&tset.src_csets))
+		return 0;
 
-	/*
-	 * step 1: check that we can legitimately attach to the cgroup.
-	 */
+	/* check that we can legitimately attach to the cgroup */
 	for_each_css(css, i, cgrp) {
 		if (css->ss->can_attach) {
-			retval = css->ss->can_attach(css, &tset);
-			if (retval) {
+			ret = css->ss->can_attach(css, &tset);
+			if (ret) {
 				failed_css = css;
 				goto out_cancel_attach;
 			}
@@ -2050,70 +1979,91 @@ static int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk,
 	}
 
 	/*
-	 * step 2: make sure css_sets exist for all threads to be migrated.
-	 * we use find_css_set, which allocates a new one if necessary.
+	 * Now that we're guaranteed success, proceed to move all tasks to
+	 * the new cgroup.  There are no failure cases after here, so this
+	 * is the commit point.
 	 */
-	for (i = 0; i < group_size; i++) {
-		struct css_set *old_cset;
-
-		tc = flex_array_get(group, i);
-		old_cset = task_css_set(tc->task);
-		tc->cset = find_css_set(old_cset, cgrp);
-		if (!tc->cset) {
-			retval = -ENOMEM;
-			goto out_put_css_set_refs;
-		}
+	down_write(&css_set_rwsem);
+	list_for_each_entry(cset, &tset.src_csets, mg_node) {
+		list_for_each_entry_safe(task, tmp_task, &cset->mg_tasks, cg_list)
+			cgroup_task_migrate(cset->mg_src_cgrp, task,
+					    cset->mg_dst_cset);
 	}
+	up_write(&css_set_rwsem);
 
 	/*
-	 * step 3: now that we're guaranteed success wrt the css_sets,
-	 * proceed to move all tasks to the new cgroup.  There are no
-	 * failure cases after here, so this is the commit point.
+	 * Migration is committed, all target tasks are now on dst_csets.
+	 * Nothing is sensitive to fork() after this point.  Notify
+	 * controllers that migration is complete.
 	 */
-	for (i = 0; i < group_size; i++) {
-		tc = flex_array_get(group, i);
-		cgroup_task_migrate(tc->cgrp, tc->task, tc->cset);
-	}
-	/* nothing is sensitive to fork() after this point. */
+	tset.csets = &tset.dst_csets;
 
-	/*
-	 * step 4: do subsystem attach callbacks.
-	 */
 	for_each_css(css, i, cgrp)
 		if (css->ss->attach)
 			css->ss->attach(css, &tset);
 
-	/*
-	 * step 5: success! and cleanup
-	 */
-	retval = 0;
-out_put_css_set_refs:
-	if (retval) {
-		for (i = 0; i < group_size; i++) {
-			tc = flex_array_get(group, i);
-			if (!tc->cset)
-				break;
-			put_css_set(tc->cset);
-		}
-	}
+	ret = 0;
+	goto out_release_tset;
+
 out_cancel_attach:
-	if (retval) {
-		for_each_css(css, i, cgrp) {
-			if (css == failed_css)
-				break;
-			if (css->ss->cancel_attach)
-				css->ss->cancel_attach(css, &tset);
-		}
+	for_each_css(css, i, cgrp) {
+		if (css == failed_css)
+			break;
+		if (css->ss->cancel_attach)
+			css->ss->cancel_attach(css, &tset);
 	}
-out_free_group_list:
-	flex_array_free(group);
-	return retval;
+out_release_tset:
+	down_write(&css_set_rwsem);
+	list_splice_init(&tset.dst_csets, &tset.src_csets);
+	list_for_each_entry_safe(cset, tmp_cset, &tset.src_csets, mg_node) {
+		list_splice_tail_init(&cset->mg_tasks, &cset->tasks);
+		list_del_init(&cset->mg_node);
+	}
+	up_write(&css_set_rwsem);
+	return ret;
+}
+
+/**
+ * cgroup_attach_task - attach a task or a whole threadgroup to a cgroup
+ * @dst_cgrp: the cgroup to attach to
+ * @leader: the task or the leader of the threadgroup to be attached
+ * @threadgroup: attach the whole threadgroup?
+ *
+ * Call holding cgroup_mutex and threadgroup_lock of @leader.
+ */
+static int cgroup_attach_task(struct cgroup *dst_cgrp,
+			      struct task_struct *leader, bool threadgroup)
+{
+	LIST_HEAD(preloaded_csets);
+	struct task_struct *task;
+	int ret;
+
+	/* look up all src csets */
+	down_read(&css_set_rwsem);
+	rcu_read_lock();
+	task = leader;
+	do {
+		cgroup_migrate_add_src(task_css_set(task), dst_cgrp,
+				       &preloaded_csets);
+		if (!threadgroup)
+			break;
+	} while_each_thread(leader, task);
+	rcu_read_unlock();
+	up_read(&css_set_rwsem);
+
+	/* prepare dst csets and commit */
+	ret = cgroup_migrate_prepare_dst(dst_cgrp, &preloaded_csets);
+	if (!ret)
+		ret = cgroup_migrate(dst_cgrp, leader, threadgroup);
+
+	cgroup_migrate_finish(&preloaded_csets);
+	return ret;
 }
 
 /*
  * Find the task_struct of the task to attach by vpid and pass it along to the
  * function to attach either it or all tasks in its threadgroup. Will lock
- * cgroup_mutex and threadgroup; may take task_lock of task.
+ * cgroup_mutex and threadgroup.
  */
 static int attach_task_by_pid(struct cgroup *cgrp, u64 pid, bool threadgroup)
 {
@@ -2198,12 +2148,19 @@ out_unlock_cgroup:
  */
 int cgroup_attach_task_all(struct task_struct *from, struct task_struct *tsk)
 {
-	struct cgroupfs_root *root;
+	struct cgroup_root *root;
 	int retval = 0;
 
 	mutex_lock(&cgroup_mutex);
-	for_each_active_root(root) {
-		struct cgroup *from_cgrp = task_cgroup_from_root(from, root);
+	for_each_root(root) {
+		struct cgroup *from_cgrp;
+
+		if (root == &cgrp_dfl_root)
+			continue;
+
+		down_read(&css_set_rwsem);
+		from_cgrp = task_cgroup_from_root(from, root);
+		up_read(&css_set_rwsem);
 
 		retval = cgroup_attach_task(from_cgrp, tsk, false);
 		if (retval)
@@ -2228,16 +2185,17 @@ static int cgroup_procs_write(struct cgroup_subsys_state *css,
 }
 
 static int cgroup_release_agent_write(struct cgroup_subsys_state *css,
-				      struct cftype *cft, const char *buffer)
+				      struct cftype *cft, char *buffer)
 {
-	BUILD_BUG_ON(sizeof(css->cgroup->root->release_agent_path) < PATH_MAX);
-	if (strlen(buffer) >= PATH_MAX)
-		return -EINVAL;
+	struct cgroup_root *root = css->cgroup->root;
+
+	BUILD_BUG_ON(sizeof(root->release_agent_path) < PATH_MAX);
 	if (!cgroup_lock_live_group(css->cgroup))
 		return -ENODEV;
-	mutex_lock(&cgroup_root_mutex);
-	strcpy(css->cgroup->root->release_agent_path, buffer);
-	mutex_unlock(&cgroup_root_mutex);
+	spin_lock(&release_agent_path_lock);
+	strlcpy(root->release_agent_path, buffer,
+		sizeof(root->release_agent_path));
+	spin_unlock(&release_agent_path_lock);
 	mutex_unlock(&cgroup_mutex);
 	return 0;
 }
@@ -2262,32 +2220,23 @@ static int cgroup_sane_behavior_show(struct seq_file *seq, void *v)
 	return 0;
 }
 
-/* A buffer size big enough for numbers or short strings */
-#define CGROUP_LOCAL_BUFFER_SIZE 64
-
-static ssize_t cgroup_file_write(struct file *file, const char __user *userbuf,
-				 size_t nbytes, loff_t *ppos)
+static ssize_t cgroup_file_write(struct kernfs_open_file *of, char *buf,
+				 size_t nbytes, loff_t off)
 {
-	struct cfent *cfe = __d_cfe(file->f_dentry);
-	struct cftype *cft = __d_cft(file->f_dentry);
-	struct cgroup_subsys_state *css = cfe->css;
-	size_t max_bytes = cft->max_write_len ?: CGROUP_LOCAL_BUFFER_SIZE - 1;
-	char *buf;
+	struct cgroup *cgrp = of->kn->parent->priv;
+	struct cftype *cft = of->kn->priv;
+	struct cgroup_subsys_state *css;
 	int ret;
 
-	if (nbytes >= max_bytes)
-		return -E2BIG;
-
-	buf = kmalloc(nbytes + 1, GFP_KERNEL);
-	if (!buf)
-		return -ENOMEM;
-
-	if (copy_from_user(buf, userbuf, nbytes)) {
-		ret = -EFAULT;
-		goto out_free;
-	}
-
-	buf[nbytes] = '\0';
+	/*
+	 * kernfs guarantees that a file isn't deleted with operations in
+	 * flight, which means that the matching css is and stays alive and
+	 * doesn't need to be pinned.  The RCU locking is not necessary
+	 * either.  It's just for the convenience of using cgroup_css().
+	 */
+	rcu_read_lock();
+	css = cgroup_css(cgrp, cft->ss);
+	rcu_read_unlock();
 
 	if (cft->write_string) {
 		ret = cft->write_string(css, cft, strstrip(buf));
@@ -2306,53 +2255,23 @@ static ssize_t cgroup_file_write(struct file *file, const char __user *userbuf,
 	} else {
 		ret = -EINVAL;
 	}
-out_free:
-	kfree(buf);
+
 	return ret ?: nbytes;
 }
 
-/*
- * seqfile ops/methods for returning structured data. Currently just
- * supports string->u64 maps, but can be extended in future.
- */
-
 static void *cgroup_seqfile_start(struct seq_file *seq, loff_t *ppos)
 {
-	struct cftype *cft = seq_cft(seq);
-
-	if (cft->seq_start) {
-		return cft->seq_start(seq, ppos);
-	} else {
-		/*
-		 * The same behavior and code as single_open().  Returns
-		 * !NULL if pos is at the beginning; otherwise, NULL.
-		 */
-		return NULL + !*ppos;
-	}
+	return seq_cft(seq)->seq_start(seq, ppos);
 }
 
 static void *cgroup_seqfile_next(struct seq_file *seq, void *v, loff_t *ppos)
 {
-	struct cftype *cft = seq_cft(seq);
-
-	if (cft->seq_next) {
-		return cft->seq_next(seq, v, ppos);
-	} else {
-		/*
-		 * The same behavior and code as single_open(), always
-		 * terminate after the initial read.
-		 */
-		++*ppos;
-		return NULL;
-	}
+	return seq_cft(seq)->seq_next(seq, v, ppos);
 }
 
 static void cgroup_seqfile_stop(struct seq_file *seq, void *v)
 {
-	struct cftype *cft = seq_cft(seq);
-
-	if (cft->seq_stop)
-		cft->seq_stop(seq, v);
+	seq_cft(seq)->seq_stop(seq, v);
 }
 
 static int cgroup_seqfile_show(struct seq_file *m, void *arg)
@@ -2372,96 +2291,35 @@ static int cgroup_seqfile_show(struct seq_file *m, void *arg)
 	return 0;
 }
 
-static struct seq_operations cgroup_seq_operations = {
-	.start		= cgroup_seqfile_start,
-	.next		= cgroup_seqfile_next,
-	.stop		= cgroup_seqfile_stop,
-	.show		= cgroup_seqfile_show,
+static struct kernfs_ops cgroup_kf_single_ops = {
+	.atomic_write_len	= PAGE_SIZE,
+	.write			= cgroup_file_write,
+	.seq_show		= cgroup_seqfile_show,
 };
 
-static int cgroup_file_open(struct inode *inode, struct file *file)
-{
-	struct cfent *cfe = __d_cfe(file->f_dentry);
-	struct cftype *cft = __d_cft(file->f_dentry);
-	struct cgroup *cgrp = __d_cgrp(cfe->dentry->d_parent);
-	struct cgroup_subsys_state *css;
-	struct cgroup_open_file *of;
-	int err;
-
-	err = generic_file_open(inode, file);
-	if (err)
-		return err;
-
-	/*
-	 * If the file belongs to a subsystem, pin the css.  Will be
-	 * unpinned either on open failure or release.  This ensures that
-	 * @css stays alive for all file operations.
-	 */
-	rcu_read_lock();
-	css = cgroup_css(cgrp, cft->ss);
-	if (cft->ss && !css_tryget(css))
-		css = NULL;
-	rcu_read_unlock();
-
-	if (!css)
-		return -ENODEV;
-
-	/*
-	 * @cfe->css is used by read/write/close to determine the
-	 * associated css.  @file->private_data would be a better place but
-	 * that's already used by seqfile.  Multiple accessors may use it
-	 * simultaneously which is okay as the association never changes.
-	 */
-	WARN_ON_ONCE(cfe->css && cfe->css != css);
-	cfe->css = css;
-
-	of = __seq_open_private(file, &cgroup_seq_operations,
-				sizeof(struct cgroup_open_file));
-	if (of) {
-		of->cfe = cfe;
-		return 0;
-	}
-
-	if (css->ss)
-		css_put(css);
-	return -ENOMEM;
-}
-
-static int cgroup_file_release(struct inode *inode, struct file *file)
-{
-	struct cfent *cfe = __d_cfe(file->f_dentry);
-	struct cgroup_subsys_state *css = cfe->css;
-
-	if (css->ss)
-		css_put(css);
-	return seq_release_private(inode, file);
-}
+static struct kernfs_ops cgroup_kf_ops = {
+	.atomic_write_len	= PAGE_SIZE,
+	.write			= cgroup_file_write,
+	.seq_start		= cgroup_seqfile_start,
+	.seq_next		= cgroup_seqfile_next,
+	.seq_stop		= cgroup_seqfile_stop,
+	.seq_show		= cgroup_seqfile_show,
+};
 
 /*
  * cgroup_rename - Only allow simple rename of directories in place.
  */
-static int cgroup_rename(struct inode *old_dir, struct dentry *old_dentry,
-			    struct inode *new_dir, struct dentry *new_dentry)
+static int cgroup_rename(struct kernfs_node *kn, struct kernfs_node *new_parent,
+			 const char *new_name_str)
 {
+	struct cgroup *cgrp = kn->priv;
 	int ret;
-	struct cgroup_name *name, *old_name;
-	struct cgroup *cgrp;
-
-	/*
-	 * It's convinient to use parent dir's i_mutex to protected
-	 * cgrp->name.
-	 */
-	lockdep_assert_held(&old_dir->i_mutex);
 
-	if (!S_ISDIR(old_dentry->d_inode->i_mode))
+	if (kernfs_type(kn) != KERNFS_DIR)
 		return -ENOTDIR;
-	if (new_dentry->d_inode)
-		return -EEXIST;
-	if (old_dir != new_dir)
+	if (kn->parent != new_parent)
 		return -EIO;
 
-	cgrp = __d_cgrp(old_dentry);
-
 	/*
 	 * This isn't a proper migration and its usefulness is very
 	 * limited.  Disallow if sane_behavior.
@@ -2469,218 +2327,61 @@ static int cgroup_rename(struct inode *old_dir, struct dentry *old_dentry,
 	if (cgroup_sane_behavior(cgrp))
 		return -EPERM;
 
-	name = cgroup_alloc_name(new_dentry);
-	if (!name)
-		return -ENOMEM;
-
-	ret = simple_rename(old_dir, old_dentry, new_dir, new_dentry);
-	if (ret) {
-		kfree(name);
-		return ret;
-	}
-
-	old_name = rcu_dereference_protected(cgrp->name, true);
-	rcu_assign_pointer(cgrp->name, name);
-
-	kfree_rcu(old_name, rcu_head);
-	return 0;
-}
-
-static struct simple_xattrs *__d_xattrs(struct dentry *dentry)
-{
-	if (S_ISDIR(dentry->d_inode->i_mode))
-		return &__d_cgrp(dentry)->xattrs;
-	else
-		return &__d_cfe(dentry)->xattrs;
-}
-
-static inline int xattr_enabled(struct dentry *dentry)
-{
-	struct cgroupfs_root *root = dentry->d_sb->s_fs_info;
-	return root->flags & CGRP_ROOT_XATTR;
-}
-
-static bool is_valid_xattr(const char *name)
-{
-	if (!strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) ||
-	    !strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN))
-		return true;
-	return false;
-}
-
-static int cgroup_setxattr(struct dentry *dentry, const char *name,
-			   const void *val, size_t size, int flags)
-{
-	if (!xattr_enabled(dentry))
-		return -EOPNOTSUPP;
-	if (!is_valid_xattr(name))
-		return -EINVAL;
-	return simple_xattr_set(__d_xattrs(dentry), name, val, size, flags);
-}
-
-static int cgroup_removexattr(struct dentry *dentry, const char *name)
-{
-	if (!xattr_enabled(dentry))
-		return -EOPNOTSUPP;
-	if (!is_valid_xattr(name))
-		return -EINVAL;
-	return simple_xattr_remove(__d_xattrs(dentry), name);
-}
-
-static ssize_t cgroup_getxattr(struct dentry *dentry, const char *name,
-			       void *buf, size_t size)
-{
-	if (!xattr_enabled(dentry))
-		return -EOPNOTSUPP;
-	if (!is_valid_xattr(name))
-		return -EINVAL;
-	return simple_xattr_get(__d_xattrs(dentry), name, buf, size);
-}
-
-static ssize_t cgroup_listxattr(struct dentry *dentry, char *buf, size_t size)
-{
-	if (!xattr_enabled(dentry))
-		return -EOPNOTSUPP;
-	return simple_xattr_list(__d_xattrs(dentry), buf, size);
-}
-
-static const struct file_operations cgroup_file_operations = {
-	.read = seq_read,
-	.write = cgroup_file_write,
-	.llseek = generic_file_llseek,
-	.open = cgroup_file_open,
-	.release = cgroup_file_release,
-};
-
-static const struct inode_operations cgroup_file_inode_operations = {
-	.setxattr = cgroup_setxattr,
-	.getxattr = cgroup_getxattr,
-	.listxattr = cgroup_listxattr,
-	.removexattr = cgroup_removexattr,
-};
-
-static const struct inode_operations cgroup_dir_inode_operations = {
-	.lookup = simple_lookup,
-	.mkdir = cgroup_mkdir,
-	.rmdir = cgroup_rmdir,
-	.rename = cgroup_rename,
-	.setxattr = cgroup_setxattr,
-	.getxattr = cgroup_getxattr,
-	.listxattr = cgroup_listxattr,
-	.removexattr = cgroup_removexattr,
-};
-
-static int cgroup_create_file(struct dentry *dentry, umode_t mode,
-				struct super_block *sb)
-{
-	struct inode *inode;
-
-	if (!dentry)
-		return -ENOENT;
-	if (dentry->d_inode)
-		return -EEXIST;
+	/*
+	 * We're gonna grab cgroup_tree_mutex which nests outside kernfs
+	 * active_ref.  kernfs_rename() doesn't require active_ref
+	 * protection.  Break them before grabbing cgroup_tree_mutex.
+	 */
+	kernfs_break_active_protection(new_parent);
+	kernfs_break_active_protection(kn);
 
-	inode = cgroup_new_inode(mode, sb);
-	if (!inode)
-		return -ENOMEM;
+	mutex_lock(&cgroup_tree_mutex);
+	mutex_lock(&cgroup_mutex);
 
-	if (S_ISDIR(mode)) {
-		inode->i_op = &cgroup_dir_inode_operations;
-		inode->i_fop = &simple_dir_operations;
+	ret = kernfs_rename(kn, new_parent, new_name_str);
 
-		/* start off with i_nlink == 2 (for "." entry) */
-		inc_nlink(inode);
-		inc_nlink(dentry->d_parent->d_inode);
+	mutex_unlock(&cgroup_mutex);
+	mutex_unlock(&cgroup_tree_mutex);
 
-		/*
-		 * Control reaches here with cgroup_mutex held.
-		 * @inode->i_mutex should nest outside cgroup_mutex but we
-		 * want to populate it immediately without releasing
-		 * cgroup_mutex.  As @inode isn't visible to anyone else
-		 * yet, trylock will always succeed without affecting
-		 * lockdep checks.
-		 */
-		WARN_ON_ONCE(!mutex_trylock(&inode->i_mutex));
-	} else if (S_ISREG(mode)) {
-		inode->i_size = 0;
-		inode->i_fop = &cgroup_file_operations;
-		inode->i_op = &cgroup_file_inode_operations;
-	}
-	d_instantiate(dentry, inode);
-	dget(dentry);	/* Extra count - pin the dentry in core */
-	return 0;
+	kernfs_unbreak_active_protection(kn);
+	kernfs_unbreak_active_protection(new_parent);
+	return ret;
 }
 
-/**
- * cgroup_file_mode - deduce file mode of a control file
- * @cft: the control file in question
- *
- * returns cft->mode if ->mode is not 0
- * returns S_IRUGO|S_IWUSR if it has both a read and a write handler
- * returns S_IRUGO if it has only a read handler
- * returns S_IWUSR if it has only a write hander
- */
-static umode_t cgroup_file_mode(const struct cftype *cft)
+/* set uid and gid of cgroup dirs and files to that of the creator */
+static int cgroup_kn_set_ugid(struct kernfs_node *kn)
 {
-	umode_t mode = 0;
+	struct iattr iattr = { .ia_valid = ATTR_UID | ATTR_GID,
+			       .ia_uid = current_fsuid(),
+			       .ia_gid = current_fsgid(), };
 
-	if (cft->mode)
-		return cft->mode;
-
-	if (cft->read_u64 || cft->read_s64 || cft->seq_show)
-		mode |= S_IRUGO;
-
-	if (cft->write_u64 || cft->write_s64 || cft->write_string ||
-	    cft->trigger)
-		mode |= S_IWUSR;
+	if (uid_eq(iattr.ia_uid, GLOBAL_ROOT_UID) &&
+	    gid_eq(iattr.ia_gid, GLOBAL_ROOT_GID))
+		return 0;
 
-	return mode;
+	return kernfs_setattr(kn, &iattr);
 }
 
 static int cgroup_add_file(struct cgroup *cgrp, struct cftype *cft)
 {
-	struct dentry *dir = cgrp->dentry;
-	struct cgroup *parent = __d_cgrp(dir);
-	struct dentry *dentry;
-	struct cfent *cfe;
-	int error;
-	umode_t mode;
-	char name[MAX_CGROUP_TYPE_NAMELEN + MAX_CFTYPE_NAME + 2] = { 0 };
-
-	if (cft->ss && !(cft->flags & CFTYPE_NO_PREFIX) &&
-	    !(cgrp->root->flags & CGRP_ROOT_NOPREFIX)) {
-		strcpy(name, cft->ss->name);
-		strcat(name, ".");
-	}
-	strcat(name, cft->name);
-
-	BUG_ON(!mutex_is_locked(&dir->d_inode->i_mutex));
-
-	cfe = kzalloc(sizeof(*cfe), GFP_KERNEL);
-	if (!cfe)
-		return -ENOMEM;
-
-	dentry = lookup_one_len(name, dir, strlen(name));
-	if (IS_ERR(dentry)) {
-		error = PTR_ERR(dentry);
-		goto out;
-	}
+	char name[CGROUP_FILE_NAME_MAX];
+	struct kernfs_node *kn;
+	struct lock_class_key *key = NULL;
+	int ret;
 
-	cfe->type = (void *)cft;
-	cfe->dentry = dentry;
-	dentry->d_fsdata = cfe;
-	simple_xattrs_init(&cfe->xattrs);
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	key = &cft->lockdep_key;
+#endif
+	kn = __kernfs_create_file(cgrp->kn, cgroup_file_name(cgrp, cft, name),
+				  cgroup_file_mode(cft), 0, cft->kf_ops, cft,
+				  NULL, false, key);
+	if (IS_ERR(kn))
+		return PTR_ERR(kn);
 
-	mode = cgroup_file_mode(cft);
-	error = cgroup_create_file(dentry, mode | S_IFREG, cgrp->root->sb);
-	if (!error) {
-		list_add_tail(&cfe->node, &parent->files);
-		cfe = NULL;
-	}
-	dput(dentry);
-out:
-	kfree(cfe);
-	return error;
+	ret = cgroup_kn_set_ugid(kn);
+	if (ret)
+		kernfs_remove(kn);
+	return ret;
 }
 
 /**
@@ -2700,11 +2401,12 @@ static int cgroup_addrm_files(struct cgroup *cgrp, struct cftype cfts[],
 	struct cftype *cft;
 	int ret;
 
-	lockdep_assert_held(&cgrp->dentry->d_inode->i_mutex);
-	lockdep_assert_held(&cgroup_mutex);
+	lockdep_assert_held(&cgroup_tree_mutex);
 
 	for (cft = cfts; cft->name[0] != '\0'; cft++) {
 		/* does cft->flags tell us to skip this file on @cgrp? */
+		if ((cft->flags & CFTYPE_ONLY_ON_DFL) && !cgroup_on_dfl(cgrp))
+			continue;
 		if ((cft->flags & CFTYPE_INSANE) && cgroup_sane_behavior(cgrp))
 			continue;
 		if ((cft->flags & CFTYPE_NOT_ON_ROOT) && !cgrp->parent)
@@ -2726,44 +2428,19 @@ static int cgroup_addrm_files(struct cgroup *cgrp, struct cftype cfts[],
 	return 0;
 }
 
-static void cgroup_cfts_prepare(void)
-	__acquires(&cgroup_mutex)
-{
-	/*
-	 * Thanks to the entanglement with vfs inode locking, we can't walk
-	 * the existing cgroups under cgroup_mutex and create files.
-	 * Instead, we use css_for_each_descendant_pre() and drop RCU read
-	 * lock before calling cgroup_addrm_files().
-	 */
-	mutex_lock(&cgroup_mutex);
-}
-
-static int cgroup_cfts_commit(struct cftype *cfts, bool is_add)
-	__releases(&cgroup_mutex)
+static int cgroup_apply_cftypes(struct cftype *cfts, bool is_add)
 {
 	LIST_HEAD(pending);
 	struct cgroup_subsys *ss = cfts[0].ss;
-	struct cgroup *root = &ss->root->top_cgroup;
-	struct super_block *sb = ss->root->sb;
-	struct dentry *prev = NULL;
-	struct inode *inode;
+	struct cgroup *root = &ss->root->cgrp;
 	struct cgroup_subsys_state *css;
-	u64 update_before;
 	int ret = 0;
 
-	/* %NULL @cfts indicates abort and don't bother if @ss isn't attached */
-	if (!cfts || ss->root == &cgroup_dummy_root ||
-	    !atomic_inc_not_zero(&sb->s_active)) {
-		mutex_unlock(&cgroup_mutex);
-		return 0;
-	}
+	lockdep_assert_held(&cgroup_tree_mutex);
 
-	/*
-	 * All cgroups which are created after we drop cgroup_mutex will
-	 * have the updated set of files, so we only need to update the
-	 * cgroups created before the current @cgroup_serial_nr_next.
-	 */
-	update_before = cgroup_serial_nr_next;
+	/* don't bother if @ss isn't attached */
+	if (ss->root == &cgrp_dfl_root)
+		return 0;
 
 	/* add/rm files for all cgroups created before */
 	css_for_each_descendant_pre(css, cgroup_css(root, ss)) {
@@ -2772,62 +2449,75 @@ static int cgroup_cfts_commit(struct cftype *cfts, bool is_add)
 		if (cgroup_is_dead(cgrp))
 			continue;
 
-		inode = cgrp->dentry->d_inode;
-		dget(cgrp->dentry);
-		dput(prev);
-		prev = cgrp->dentry;
-
-		mutex_unlock(&cgroup_mutex);
-		mutex_lock(&inode->i_mutex);
-		mutex_lock(&cgroup_mutex);
-		if (cgrp->serial_nr < update_before && !cgroup_is_dead(cgrp))
-			ret = cgroup_addrm_files(cgrp, cfts, is_add);
-		mutex_unlock(&inode->i_mutex);
+		ret = cgroup_addrm_files(cgrp, cfts, is_add);
 		if (ret)
 			break;
 	}
-	mutex_unlock(&cgroup_mutex);
-	dput(prev);
-	deactivate_super(sb);
+
+	if (is_add && !ret)
+		kernfs_activate(root->kn);
 	return ret;
 }
 
-/**
- * cgroup_add_cftypes - add an array of cftypes to a subsystem
- * @ss: target cgroup subsystem
- * @cfts: zero-length name terminated array of cftypes
- *
- * Register @cfts to @ss.  Files described by @cfts are created for all
- * existing cgroups to which @ss is attached and all future cgroups will
- * have them too.  This function can be called anytime whether @ss is
- * attached or not.
- *
- * Returns 0 on successful registration, -errno on failure.  Note that this
- * function currently returns 0 as long as @cfts registration is successful
- * even if some file creation attempts on existing cgroups fail.
- */
-int cgroup_add_cftypes(struct cgroup_subsys *ss, struct cftype *cfts)
+static void cgroup_exit_cftypes(struct cftype *cfts)
 {
-	struct cftype_set *set;
 	struct cftype *cft;
-	int ret;
 
-	set = kzalloc(sizeof(*set), GFP_KERNEL);
-	if (!set)
-		return -ENOMEM;
+	for (cft = cfts; cft->name[0] != '\0'; cft++) {
+		/* free copy for custom atomic_write_len, see init_cftypes() */
+		if (cft->max_write_len && cft->max_write_len != PAGE_SIZE)
+			kfree(cft->kf_ops);
+		cft->kf_ops = NULL;
+		cft->ss = NULL;
+	}
+}
+
+static int cgroup_init_cftypes(struct cgroup_subsys *ss, struct cftype *cfts)
+{
+	struct cftype *cft;
 
-	for (cft = cfts; cft->name[0] != '\0'; cft++)
+	for (cft = cfts; cft->name[0] != '\0'; cft++) {
+		struct kernfs_ops *kf_ops;
+
+		WARN_ON(cft->ss || cft->kf_ops);
+
+		if (cft->seq_start)
+			kf_ops = &cgroup_kf_ops;
+		else
+			kf_ops = &cgroup_kf_single_ops;
+
+		/*
+		 * Ugh... if @cft wants a custom max_write_len, we need to
+		 * make a copy of kf_ops to set its atomic_write_len.
+		 */
+		if (cft->max_write_len && cft->max_write_len != PAGE_SIZE) {
+			kf_ops = kmemdup(kf_ops, sizeof(*kf_ops), GFP_KERNEL);
+			if (!kf_ops) {
+				cgroup_exit_cftypes(cfts);
+				return -ENOMEM;
+			}
+			kf_ops->atomic_write_len = cft->max_write_len;
+		}
+
+		cft->kf_ops = kf_ops;
 		cft->ss = ss;
+	}
 
-	cgroup_cfts_prepare();
-	set->cfts = cfts;
-	list_add_tail(&set->node, &ss->cftsets);
-	ret = cgroup_cfts_commit(cfts, true);
-	if (ret)
-		cgroup_rm_cftypes(cfts);
-	return ret;
+	return 0;
+}
+
+static int cgroup_rm_cftypes_locked(struct cftype *cfts)
+{
+	lockdep_assert_held(&cgroup_tree_mutex);
+
+	if (!cfts || !cfts[0].ss)
+		return -ENOENT;
+
+	list_del(&cfts->node);
+	cgroup_apply_cftypes(cfts, false);
+	cgroup_exit_cftypes(cfts);
+	return 0;
 }
-EXPORT_SYMBOL_GPL(cgroup_add_cftypes);
 
 /**
  * cgroup_rm_cftypes - remove an array of cftypes from a subsystem
@@ -2842,24 +2532,48 @@ EXPORT_SYMBOL_GPL(cgroup_add_cftypes);
  */
 int cgroup_rm_cftypes(struct cftype *cfts)
 {
-	struct cftype_set *set;
+	int ret;
 
-	if (!cfts || !cfts[0].ss)
-		return -ENOENT;
+	mutex_lock(&cgroup_tree_mutex);
+	ret = cgroup_rm_cftypes_locked(cfts);
+	mutex_unlock(&cgroup_tree_mutex);
+	return ret;
+}
 
-	cgroup_cfts_prepare();
+/**
+ * cgroup_add_cftypes - add an array of cftypes to a subsystem
+ * @ss: target cgroup subsystem
+ * @cfts: zero-length name terminated array of cftypes
+ *
+ * Register @cfts to @ss.  Files described by @cfts are created for all
+ * existing cgroups to which @ss is attached and all future cgroups will
+ * have them too.  This function can be called anytime whether @ss is
+ * attached or not.
+ *
+ * Returns 0 on successful registration, -errno on failure.  Note that this
+ * function currently returns 0 as long as @cfts registration is successful
+ * even if some file creation attempts on existing cgroups fail.
+ */
+int cgroup_add_cftypes(struct cgroup_subsys *ss, struct cftype *cfts)
+{
+	int ret;
 
-	list_for_each_entry(set, &cfts[0].ss->cftsets, node) {
-		if (set->cfts == cfts) {
-			list_del(&set->node);
-			kfree(set);
-			cgroup_cfts_commit(cfts, false);
-			return 0;
-		}
-	}
+	if (!cfts || cfts[0].name[0] == '\0')
+		return 0;
 
-	cgroup_cfts_commit(NULL, false);
-	return -ENOENT;
+	ret = cgroup_init_cftypes(ss, cfts);
+	if (ret)
+		return ret;
+
+	mutex_lock(&cgroup_tree_mutex);
+
+	list_add_tail(&cfts->node, &ss->cfts);
+	ret = cgroup_apply_cftypes(cfts, true);
+	if (ret)
+		cgroup_rm_cftypes_locked(cfts);
+
+	mutex_unlock(&cgroup_tree_mutex);
+	return ret;
 }
 
 /**
@@ -2868,57 +2582,18 @@ int cgroup_rm_cftypes(struct cftype *cfts)
  *
  * Return the number of tasks in the cgroup.
  */
-int cgroup_task_count(const struct cgroup *cgrp)
+static int cgroup_task_count(const struct cgroup *cgrp)
 {
 	int count = 0;
 	struct cgrp_cset_link *link;
 
-	read_lock(&css_set_lock);
+	down_read(&css_set_rwsem);
 	list_for_each_entry(link, &cgrp->cset_links, cset_link)
 		count += atomic_read(&link->cset->refcount);
-	read_unlock(&css_set_lock);
+	up_read(&css_set_rwsem);
 	return count;
 }
 
-/*
- * To reduce the fork() overhead for systems that are not actually using
- * their cgroups capability, we don't maintain the lists running through
- * each css_set to its tasks until we see the list actually used - in other
- * words after the first call to css_task_iter_start().
- */
-static void cgroup_enable_task_cg_lists(void)
-{
-	struct task_struct *p, *g;
-	write_lock(&css_set_lock);
-	use_task_css_set_links = 1;
-	/*
-	 * We need tasklist_lock because RCU is not safe against
-	 * while_each_thread(). Besides, a forking task that has passed
-	 * cgroup_post_fork() without seeing use_task_css_set_links = 1
-	 * is not guaranteed to have its child immediately visible in the
-	 * tasklist if we walk through it with RCU.
-	 */
-	read_lock(&tasklist_lock);
-	do_each_thread(g, p) {
-		task_lock(p);
-		/*
-		 * We should check if the process is exiting, otherwise
-		 * it will race with cgroup_exit() in that the list
-		 * entry won't be deleted though the process has exited.
-		 * Do it while holding siglock so that we don't end up
-		 * racing against cgroup_exit().
-		 */
-		spin_lock_irq(&p->sighand->siglock);
-		if (!(p->flags & PF_EXITING) && list_empty(&p->cg_list))
-			list_add(&p->cg_list, &task_css_set(p)->tasks);
-		spin_unlock_irq(&p->sighand->siglock);
-
-		task_unlock(p);
-	} while_each_thread(g, p);
-	read_unlock(&tasklist_lock);
-	write_unlock(&css_set_lock);
-}
-
 /**
  * css_next_child - find the next child of a given css
  * @pos_css: the current position (%NULL to initiate traversal)
@@ -2937,7 +2612,7 @@ css_next_child(struct cgroup_subsys_state *pos_css,
 	struct cgroup *cgrp = parent_css->cgroup;
 	struct cgroup *next;
 
-	cgroup_assert_mutex_or_rcu_locked();
+	cgroup_assert_mutexes_or_rcu_locked();
 
 	/*
 	 * @pos could already have been removed.  Once a cgroup is removed,
@@ -2973,7 +2648,6 @@ css_next_child(struct cgroup_subsys_state *pos_css,
 
 	return cgroup_css(next, parent_css->ss);
 }
-EXPORT_SYMBOL_GPL(css_next_child);
 
 /**
  * css_next_descendant_pre - find the next descendant for pre-order walk
@@ -2995,7 +2669,7 @@ css_next_descendant_pre(struct cgroup_subsys_state *pos,
 {
 	struct cgroup_subsys_state *next;
 
-	cgroup_assert_mutex_or_rcu_locked();
+	cgroup_assert_mutexes_or_rcu_locked();
 
 	/* if first iteration, visit @root */
 	if (!pos)
@@ -3016,7 +2690,6 @@ css_next_descendant_pre(struct cgroup_subsys_state *pos,
 
 	return NULL;
 }
-EXPORT_SYMBOL_GPL(css_next_descendant_pre);
 
 /**
  * css_rightmost_descendant - return the rightmost descendant of a css
@@ -3036,7 +2709,7 @@ css_rightmost_descendant(struct cgroup_subsys_state *pos)
 {
 	struct cgroup_subsys_state *last, *tmp;
 
-	cgroup_assert_mutex_or_rcu_locked();
+	cgroup_assert_mutexes_or_rcu_locked();
 
 	do {
 		last = pos;
@@ -3048,7 +2721,6 @@ css_rightmost_descendant(struct cgroup_subsys_state *pos)
 
 	return last;
 }
-EXPORT_SYMBOL_GPL(css_rightmost_descendant);
 
 static struct cgroup_subsys_state *
 css_leftmost_descendant(struct cgroup_subsys_state *pos)
@@ -3084,7 +2756,7 @@ css_next_descendant_post(struct cgroup_subsys_state *pos,
 {
 	struct cgroup_subsys_state *next;
 
-	cgroup_assert_mutex_or_rcu_locked();
+	cgroup_assert_mutexes_or_rcu_locked();
 
 	/* if first iteration, visit leftmost descendant which may be @root */
 	if (!pos)
@@ -3102,7 +2774,6 @@ css_next_descendant_post(struct cgroup_subsys_state *pos,
 	/* no sibling left, visit parent */
 	return css_parent(pos);
 }
-EXPORT_SYMBOL_GPL(css_next_descendant_post);
 
 /**
  * css_advance_task_iter - advance a task itererator to the next css_set
@@ -3125,9 +2796,14 @@ static void css_advance_task_iter(struct css_task_iter *it)
 		}
 		link = list_entry(l, struct cgrp_cset_link, cset_link);
 		cset = link->cset;
-	} while (list_empty(&cset->tasks));
+	} while (list_empty(&cset->tasks) && list_empty(&cset->mg_tasks));
+
 	it->cset_link = l;
-	it->task = cset->tasks.next;
+
+	if (!list_empty(&cset->tasks))
+		it->task = cset->tasks.next;
+	else
+		it->task = cset->mg_tasks.next;
 }
 
 /**
@@ -3146,17 +2822,12 @@ static void css_advance_task_iter(struct css_task_iter *it)
  */
 void css_task_iter_start(struct cgroup_subsys_state *css,
 			 struct css_task_iter *it)
-	__acquires(css_set_lock)
+	__acquires(css_set_rwsem)
 {
-	/*
-	 * The first time anyone tries to iterate across a css, we need to
-	 * enable the list linking each css_set to its tasks, and fix up
-	 * all existing tasks.
-	 */
-	if (!use_task_css_set_links)
-		cgroup_enable_task_cg_lists();
+	/* no one should try to iterate before mounting cgroups */
+	WARN_ON_ONCE(!use_task_css_set_links);
 
-	read_lock(&css_set_lock);
+	down_read(&css_set_rwsem);
 
 	it->origin_css = css;
 	it->cset_link = &css->cgroup->cset_links;
@@ -3176,24 +2847,29 @@ struct task_struct *css_task_iter_next(struct css_task_iter *it)
 {
 	struct task_struct *res;
 	struct list_head *l = it->task;
-	struct cgrp_cset_link *link;
+	struct cgrp_cset_link *link = list_entry(it->cset_link,
+					struct cgrp_cset_link, cset_link);
 
 	/* If the iterator cg is NULL, we have no tasks */
 	if (!it->cset_link)
 		return NULL;
 	res = list_entry(l, struct task_struct, cg_list);
-	/* Advance iterator to find next entry */
+
+	/*
+	 * Advance iterator to find next entry.  cset->tasks is consumed
+	 * first and then ->mg_tasks.  After ->mg_tasks, we move onto the
+	 * next cset.
+	 */
 	l = l->next;
-	link = list_entry(it->cset_link, struct cgrp_cset_link, cset_link);
-	if (l == &link->cset->tasks) {
-		/*
-		 * We reached the end of this task list - move on to the
-		 * next cgrp_cset_link.
-		 */
+
+	if (l == &link->cset->tasks)
+		l = link->cset->mg_tasks.next;
+
+	if (l == &link->cset->mg_tasks)
 		css_advance_task_iter(it);
-	} else {
+	else
 		it->task = l;
-	}
+
 	return res;
 }
 
@@ -3204,191 +2880,62 @@ struct task_struct *css_task_iter_next(struct css_task_iter *it)
  * Finish task iteration started by css_task_iter_start().
  */
 void css_task_iter_end(struct css_task_iter *it)
-	__releases(css_set_lock)
-{
-	read_unlock(&css_set_lock);
-}
-
-static inline int started_after_time(struct task_struct *t1,
-				     struct timespec *time,
-				     struct task_struct *t2)
-{
-	int start_diff = timespec_compare(&t1->start_time, time);
-	if (start_diff > 0) {
-		return 1;
-	} else if (start_diff < 0) {
-		return 0;
-	} else {
-		/*
-		 * Arbitrarily, if two processes started at the same
-		 * time, we'll say that the lower pointer value
-		 * started first. Note that t2 may have exited by now
-		 * so this may not be a valid pointer any longer, but
-		 * that's fine - it still serves to distinguish
-		 * between two tasks started (effectively) simultaneously.
-		 */
-		return t1 > t2;
-	}
-}
-
-/*
- * This function is a callback from heap_insert() and is used to order
- * the heap.
- * In this case we order the heap in descending task start time.
- */
-static inline int started_after(void *p1, void *p2)
+	__releases(css_set_rwsem)
 {
-	struct task_struct *t1 = p1;
-	struct task_struct *t2 = p2;
-	return started_after_time(t1, &t2->start_time, t2);
+	up_read(&css_set_rwsem);
 }
 
 /**
- * css_scan_tasks - iterate though all the tasks in a css
- * @css: the css to iterate tasks of
- * @test: optional test callback
- * @process: process callback
- * @data: data passed to @test and @process
- * @heap: optional pre-allocated heap used for task iteration
- *
- * Iterate through all the tasks in @css, calling @test for each, and if it
- * returns %true, call @process for it also.
- *
- * @test may be NULL, meaning always true (select all tasks), which
- * effectively duplicates css_task_iter_{start,next,end}() but does not
- * lock css_set_lock for the call to @process.
- *
- * It is guaranteed that @process will act on every task that is a member
- * of @css for the duration of this call.  This function may or may not
- * call @process for tasks that exit or move to a different css during the
- * call, or are forked or move into the css during the call.
- *
- * Note that @test may be called with locks held, and may in some
- * situations be called multiple times for the same task, so it should be
- * cheap.
+ * cgroup_trasnsfer_tasks - move tasks from one cgroup to another
+ * @to: cgroup to which the tasks will be moved
+ * @from: cgroup in which the tasks currently reside
  *
- * If @heap is non-NULL, a heap has been pre-allocated and will be used for
- * heap operations (and its "gt" member will be overwritten), else a
- * temporary heap will be used (allocation of which may cause this function
- * to fail).
+ * Locking rules between cgroup_post_fork() and the migration path
+ * guarantee that, if a task is forking while being migrated, the new child
+ * is guaranteed to be either visible in the source cgroup after the
+ * parent's migration is complete or put into the target cgroup.  No task
+ * can slip out of migration through forking.
  */
-int css_scan_tasks(struct cgroup_subsys_state *css,
-		   bool (*test)(struct task_struct *, void *),
-		   void (*process)(struct task_struct *, void *),
-		   void *data, struct ptr_heap *heap)
+int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from)
 {
-	int retval, i;
+	LIST_HEAD(preloaded_csets);
+	struct cgrp_cset_link *link;
 	struct css_task_iter it;
-	struct task_struct *p, *dropped;
-	/* Never dereference latest_task, since it's not refcounted */
-	struct task_struct *latest_task = NULL;
-	struct ptr_heap tmp_heap;
-	struct timespec latest_time = { 0, 0 };
-
-	if (heap) {
-		/* The caller supplied our heap and pre-allocated its memory */
-		heap->gt = &started_after;
-	} else {
-		/* We need to allocate our own heap memory */
-		heap = &tmp_heap;
-		retval = heap_init(heap, PAGE_SIZE, GFP_KERNEL, &started_after);
-		if (retval)
-			/* cannot allocate the heap */
-			return retval;
-	}
+	struct task_struct *task;
+	int ret;
 
- again:
-	/*
-	 * Scan tasks in the css, using the @test callback to determine
-	 * which are of interest, and invoking @process callback on the
-	 * ones which need an update.  Since we don't want to hold any
-	 * locks during the task updates, gather tasks to be processed in a
-	 * heap structure.  The heap is sorted by descending task start
-	 * time.  If the statically-sized heap fills up, we overflow tasks
-	 * that started later, and in future iterations only consider tasks
-	 * that started after the latest task in the previous pass. This
-	 * guarantees forward progress and that we don't miss any tasks.
-	 */
-	heap->size = 0;
-	css_task_iter_start(css, &it);
-	while ((p = css_task_iter_next(&it))) {
-		/*
-		 * Only affect tasks that qualify per the caller's callback,
-		 * if he provided one
-		 */
-		if (test && !test(p, data))
-			continue;
-		/*
-		 * Only process tasks that started after the last task
-		 * we processed
-		 */
-		if (!started_after_time(p, &latest_time, latest_task))
-			continue;
-		dropped = heap_insert(heap, p);
-		if (dropped == NULL) {
-			/*
-			 * The new task was inserted; the heap wasn't
-			 * previously full
-			 */
-			get_task_struct(p);
-		} else if (dropped != p) {
-			/*
-			 * The new task was inserted, and pushed out a
-			 * different task
-			 */
-			get_task_struct(p);
-			put_task_struct(dropped);
-		}
-		/*
-		 * Else the new task was newer than anything already in
-		 * the heap and wasn't inserted
-		 */
-	}
-	css_task_iter_end(&it);
+	mutex_lock(&cgroup_mutex);
 
-	if (heap->size) {
-		for (i = 0; i < heap->size; i++) {
-			struct task_struct *q = heap->ptrs[i];
-			if (i == 0) {
-				latest_time = q->start_time;
-				latest_task = q;
-			}
-			/* Process the task per the caller's callback */
-			process(q, data);
-			put_task_struct(q);
-		}
-		/*
-		 * If we had to process any tasks at all, scan again
-		 * in case some of them were in the middle of forking
-		 * children that didn't get processed.
-		 * Not the most efficient way to do it, but it avoids
-		 * having to take callback_mutex in the fork path
-		 */
-		goto again;
-	}
-	if (heap == &tmp_heap)
-		heap_free(&tmp_heap);
-	return 0;
-}
+	/* all tasks in @from are being moved, all csets are source */
+	down_read(&css_set_rwsem);
+	list_for_each_entry(link, &from->cset_links, cset_link)
+		cgroup_migrate_add_src(link->cset, to, &preloaded_csets);
+	up_read(&css_set_rwsem);
 
-static void cgroup_transfer_one_task(struct task_struct *task, void *data)
-{
-	struct cgroup *new_cgroup = data;
+	ret = cgroup_migrate_prepare_dst(to, &preloaded_csets);
+	if (ret)
+		goto out_err;
 
-	mutex_lock(&cgroup_mutex);
-	cgroup_attach_task(new_cgroup, task, false);
+	/*
+	 * Migrate tasks one-by-one until @form is empty.  This fails iff
+	 * ->can_attach() fails.
+	 */
+	do {
+		css_task_iter_start(&from->dummy_css, &it);
+		task = css_task_iter_next(&it);
+		if (task)
+			get_task_struct(task);
+		css_task_iter_end(&it);
+
+		if (task) {
+			ret = cgroup_migrate(to, task, false);
+			put_task_struct(task);
+		}
+	} while (task && !ret);
+out_err:
+	cgroup_migrate_finish(&preloaded_csets);
 	mutex_unlock(&cgroup_mutex);
-}
-
-/**
- * cgroup_trasnsfer_tasks - move tasks from one cgroup to another
- * @to: cgroup to which the tasks will be moved
- * @from: cgroup in which the tasks currently reside
- */
-int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from)
-{
-	return css_scan_tasks(&from->dummy_css, NULL, cgroup_transfer_one_task,
-			      to, NULL);
+	return ret;
 }
 
 /*
@@ -3687,21 +3234,31 @@ static int pidlist_array_load(struct cgroup *cgrp, enum cgroup_filetype type,
  */
 int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry)
 {
-	int ret = -EINVAL;
+	struct kernfs_node *kn = kernfs_node_from_dentry(dentry);
 	struct cgroup *cgrp;
 	struct css_task_iter it;
 	struct task_struct *tsk;
 
+	/* it should be kernfs_node belonging to cgroupfs and is a directory */
+	if (dentry->d_sb->s_type != &cgroup_fs_type || !kn ||
+	    kernfs_type(kn) != KERNFS_DIR)
+		return -EINVAL;
+
+	mutex_lock(&cgroup_mutex);
+
 	/*
-	 * Validate dentry by checking the superblock operations,
-	 * and make sure it's a directory.
+	 * We aren't being called from kernfs and there's no guarantee on
+	 * @kn->priv's validity.  For this and css_tryget_from_dir(),
+	 * @kn->priv is RCU safe.  Let's do the RCU dancing.
 	 */
-	if (dentry->d_sb->s_op != &cgroup_ops ||
-	    !S_ISDIR(dentry->d_inode->i_mode))
-		 goto err;
-
-	ret = 0;
-	cgrp = dentry->d_fsdata;
+	rcu_read_lock();
+	cgrp = rcu_dereference(kn->priv);
+	if (!cgrp || cgroup_is_dead(cgrp)) {
+		rcu_read_unlock();
+		mutex_unlock(&cgroup_mutex);
+		return -ENOENT;
+	}
+	rcu_read_unlock();
 
 	css_task_iter_start(&cgrp->dummy_css, &it);
 	while ((tsk = css_task_iter_next(&it))) {
@@ -3726,8 +3283,8 @@ int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry)
 	}
 	css_task_iter_end(&it);
 
-err:
-	return ret;
+	mutex_unlock(&cgroup_mutex);
+	return 0;
 }
 
 
@@ -3745,7 +3302,7 @@ static void *cgroup_pidlist_start(struct seq_file *s, loff_t *pos)
 	 * after a seek to the start). Use a binary-search to find the
 	 * next pid to display, if any
 	 */
-	struct cgroup_open_file *of = s->private;
+	struct kernfs_open_file *of = s->private;
 	struct cgroup *cgrp = seq_css(s)->cgroup;
 	struct cgroup_pidlist *l;
 	enum cgroup_filetype type = seq_cft(s)->private;
@@ -3800,7 +3357,7 @@ static void *cgroup_pidlist_start(struct seq_file *s, loff_t *pos)
 
 static void cgroup_pidlist_stop(struct seq_file *s, void *v)
 {
-	struct cgroup_open_file *of = s->private;
+	struct kernfs_open_file *of = s->private;
 	struct cgroup_pidlist *l = of->priv;
 
 	if (l)
@@ -3811,7 +3368,7 @@ static void cgroup_pidlist_stop(struct seq_file *s, void *v)
 
 static void *cgroup_pidlist_next(struct seq_file *s, void *v, loff_t *pos)
 {
-	struct cgroup_open_file *of = s->private;
+	struct kernfs_open_file *of = s->private;
 	struct cgroup_pidlist *l = of->priv;
 	pid_t *p = v;
 	pid_t *end = l->list + l->length;
@@ -3861,23 +3418,6 @@ static int cgroup_write_notify_on_release(struct cgroup_subsys_state *css,
 	return 0;
 }
 
-/*
- * When dput() is called asynchronously, if umount has been done and
- * then deactivate_super() in cgroup_free_fn() kills the superblock,
- * there's a small window that vfs will see the root dentry with non-zero
- * refcnt and trigger BUG().
- *
- * That's why we hold a reference before dput() and drop it right after.
- */
-static void cgroup_dput(struct cgroup *cgrp)
-{
-	struct super_block *sb = cgrp->root->sb;
-
-	atomic_inc(&sb->s_active);
-	dput(cgrp->dentry);
-	deactivate_super(sb);
-}
-
 static u64 cgroup_clone_children_read(struct cgroup_subsys_state *css,
 				      struct cftype *cft)
 {
@@ -3944,7 +3484,7 @@ static struct cftype cgroup_base_files[] = {
 		.flags = CFTYPE_INSANE | CFTYPE_ONLY_ON_ROOT,
 		.seq_show = cgroup_release_agent_show,
 		.write_string = cgroup_release_agent_write,
-		.max_write_len = PATH_MAX,
+		.max_write_len = PATH_MAX - 1,
 	},
 	{ }	/* terminate */
 };
@@ -3963,13 +3503,13 @@ static int cgroup_populate_dir(struct cgroup *cgrp, unsigned long subsys_mask)
 
 	/* process cftsets of each subsystem */
 	for_each_subsys(ss, i) {
-		struct cftype_set *set;
+		struct cftype *cfts;
 
 		if (!test_bit(i, &subsys_mask))
 			continue;
 
-		list_for_each_entry(set, &ss->cftsets, node) {
-			ret = cgroup_addrm_files(cgrp, set->cfts, true);
+		list_for_each_entry(cfts, &ss->cfts, node) {
+			ret = cgroup_addrm_files(cgrp, cfts, true);
 			if (ret < 0)
 				goto err;
 		}
@@ -4012,7 +3552,7 @@ static void css_free_work_fn(struct work_struct *work)
 		css_put(css->parent);
 
 	css->ss->css_free(css);
-	cgroup_dput(cgrp);
+	cgroup_put(cgrp);
 }
 
 static void css_free_rcu_fn(struct rcu_head *rcu_head)
@@ -4020,10 +3560,6 @@ static void css_free_rcu_fn(struct rcu_head *rcu_head)
 	struct cgroup_subsys_state *css =
 		container_of(rcu_head, struct cgroup_subsys_state, rcu_head);
 
-	/*
-	 * css holds an extra ref to @cgrp->dentry which is put on the last
-	 * css_put().  dput() requires process context which we don't have.
-	 */
 	INIT_WORK(&css->destroy_work, css_free_work_fn);
 	queue_work(cgroup_destroy_wq, &css->destroy_work);
 }
@@ -4033,7 +3569,7 @@ static void css_release(struct percpu_ref *ref)
 	struct cgroup_subsys_state *css =
 		container_of(ref, struct cgroup_subsys_state, refcnt);
 
-	rcu_assign_pointer(css->cgroup->subsys[css->ss->subsys_id], NULL);
+	RCU_INIT_POINTER(css->cgroup->subsys[css->ss->id], NULL);
 	call_rcu(&css->rcu_head, css_free_rcu_fn);
 }
 
@@ -4058,6 +3594,7 @@ static int online_css(struct cgroup_subsys_state *css)
 	struct cgroup_subsys *ss = css->ss;
 	int ret = 0;
 
+	lockdep_assert_held(&cgroup_tree_mutex);
 	lockdep_assert_held(&cgroup_mutex);
 
 	if (ss->css_online)
@@ -4065,7 +3602,7 @@ static int online_css(struct cgroup_subsys_state *css)
 	if (!ret) {
 		css->flags |= CSS_ONLINE;
 		css->cgroup->nr_css++;
-		rcu_assign_pointer(css->cgroup->subsys[ss->subsys_id], css);
+		rcu_assign_pointer(css->cgroup->subsys[ss->id], css);
 	}
 	return ret;
 }
@@ -4075,6 +3612,7 @@ static void offline_css(struct cgroup_subsys_state *css)
 {
 	struct cgroup_subsys *ss = css->ss;
 
+	lockdep_assert_held(&cgroup_tree_mutex);
 	lockdep_assert_held(&cgroup_mutex);
 
 	if (!(css->flags & CSS_ONLINE))
@@ -4085,7 +3623,7 @@ static void offline_css(struct cgroup_subsys_state *css)
 
 	css->flags &= ~CSS_ONLINE;
 	css->cgroup->nr_css--;
-	RCU_INIT_POINTER(css->cgroup->subsys[ss->subsys_id], css);
+	RCU_INIT_POINTER(css->cgroup->subsys[ss->id], css);
 }
 
 /**
@@ -4103,7 +3641,6 @@ static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss)
 	struct cgroup_subsys_state *css;
 	int err;
 
-	lockdep_assert_held(&cgrp->dentry->d_inode->i_mutex);
 	lockdep_assert_held(&cgroup_mutex);
 
 	css = ss->css_alloc(cgroup_css(parent, ss));
@@ -4116,7 +3653,7 @@ static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss)
 
 	init_css(css, ss, cgrp);
 
-	err = cgroup_populate_dir(cgrp, 1 << ss->subsys_id);
+	err = cgroup_populate_dir(cgrp, 1 << ss->id);
 	if (err)
 		goto err_free_percpu_ref;
 
@@ -4124,9 +3661,11 @@ static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss)
 	if (err)
 		goto err_clear_dir;
 
-	dget(cgrp->dentry);
+	cgroup_get(cgrp);
 	css_get(css->parent);
 
+	cgrp->subsys_mask |= 1 << ss->id;
+
 	if (ss->broken_hierarchy && !ss->warned_broken_hierarchy &&
 	    parent->parent) {
 		pr_warning("cgroup: %s (%d) created nested cgroup for controller \"%s\" which has incomplete hierarchy support. Nested cgroups may change behavior in the future.\n",
@@ -4139,7 +3678,7 @@ static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss)
 	return 0;
 
 err_clear_dir:
-	cgroup_clear_dir(css->cgroup, 1 << css->ss->subsys_id);
+	cgroup_clear_dir(css->cgroup, 1 << css->ss->id);
 err_free_percpu_ref:
 	percpu_ref_cancel_init(&css->refcnt);
 err_free_css:
@@ -4147,35 +3686,34 @@ err_free_css:
 	return err;
 }
 
-/*
+/**
  * cgroup_create - create a cgroup
  * @parent: cgroup that will be parent of the new cgroup
- * @dentry: dentry of the new cgroup
- * @mode: mode to set on new inode
- *
- * Must be called with the mutex on the parent inode held
+ * @name: name of the new cgroup
+ * @mode: mode to set on new cgroup
  */
-static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
-			     umode_t mode)
+static long cgroup_create(struct cgroup *parent, const char *name,
+			  umode_t mode)
 {
 	struct cgroup *cgrp;
-	struct cgroup_name *name;
-	struct cgroupfs_root *root = parent->root;
+	struct cgroup_root *root = parent->root;
 	int ssid, err;
 	struct cgroup_subsys *ss;
-	struct super_block *sb = root->sb;
+	struct kernfs_node *kn;
+
+	/*
+	 * XXX: The default hierarchy isn't fully implemented yet.  Block
+	 * !root cgroup creation on it for now.
+	 */
+	if (root == &cgrp_dfl_root)
+		return -EINVAL;
 
 	/* allocate the cgroup and its ID, 0 is reserved for the root */
 	cgrp = kzalloc(sizeof(*cgrp), GFP_KERNEL);
 	if (!cgrp)
 		return -ENOMEM;
 
-	name = cgroup_alloc_name(dentry);
-	if (!name) {
-		err = -ENOMEM;
-		goto err_free_cgrp;
-	}
-	rcu_assign_pointer(cgrp->name, name);
+	mutex_lock(&cgroup_tree_mutex);
 
 	/*
 	 * Only live parents can have children.  Note that the liveliness
@@ -4186,7 +3724,7 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
 	 */
 	if (!cgroup_lock_live_group(parent)) {
 		err = -ENODEV;
-		goto err_free_name;
+		goto err_unlock_tree;
 	}
 
 	/*
@@ -4199,18 +3737,8 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
 		goto err_unlock;
 	}
 
-	/* Grab a reference on the superblock so the hierarchy doesn't
-	 * get deleted on unmount if there are child cgroups.  This
-	 * can be done outside cgroup_mutex, since the sb can't
-	 * disappear while someone has an open control file on the
-	 * fs */
-	atomic_inc(&sb->s_active);
-
 	init_cgroup_housekeeping(cgrp);
 
-	dentry->d_fsdata = cgrp;
-	cgrp->dentry = dentry;
-
 	cgrp->parent = parent;
 	cgrp->dummy_css.parent = &parent->dummy_css;
 	cgrp->root = parent->root;
@@ -4221,24 +3749,26 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
 	if (test_bit(CGRP_CPUSET_CLONE_CHILDREN, &parent->flags))
 		set_bit(CGRP_CPUSET_CLONE_CHILDREN, &cgrp->flags);
 
+	/* create the directory */
+	kn = kernfs_create_dir(parent->kn, name, mode, cgrp);
+	if (IS_ERR(kn)) {
+		err = PTR_ERR(kn);
+		goto err_free_id;
+	}
+	cgrp->kn = kn;
+
 	/*
-	 * Create directory.  cgroup_create_file() returns with the new
-	 * directory locked on success so that it can be populated without
-	 * dropping cgroup_mutex.
+	 * This extra ref will be put in cgroup_free_fn() and guarantees
+	 * that @cgrp->kn is always accessible.
 	 */
-	err = cgroup_create_file(dentry, S_IFDIR | mode, sb);
-	if (err < 0)
-		goto err_free_id;
-	lockdep_assert_held(&dentry->d_inode->i_mutex);
+	kernfs_get(kn);
 
 	cgrp->serial_nr = cgroup_serial_nr_next++;
 
 	/* allocation complete, commit to creation */
 	list_add_tail_rcu(&cgrp->sibling, &cgrp->parent->children);
-	root->number_of_cgroups++;
-
-	/* hold a ref to the parent's dentry */
-	dget(parent->dentry);
+	atomic_inc(&root->nr_cgrps);
+	cgroup_get(parent);
 
 	/*
 	 * @cgrp is now fully operational.  If something fails after this
@@ -4246,49 +3776,66 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
 	 */
 	idr_replace(&root->cgroup_idr, cgrp, cgrp->id);
 
+	err = cgroup_kn_set_ugid(kn);
+	if (err)
+		goto err_destroy;
+
 	err = cgroup_addrm_files(cgrp, cgroup_base_files, true);
 	if (err)
 		goto err_destroy;
 
 	/* let's create and online css's */
 	for_each_subsys(ss, ssid) {
-		if (root->subsys_mask & (1 << ssid)) {
+		if (root->cgrp.subsys_mask & (1 << ssid)) {
 			err = create_css(cgrp, ss);
 			if (err)
 				goto err_destroy;
 		}
 	}
 
+	kernfs_activate(kn);
+
 	mutex_unlock(&cgroup_mutex);
-	mutex_unlock(&cgrp->dentry->d_inode->i_mutex);
+	mutex_unlock(&cgroup_tree_mutex);
 
 	return 0;
 
 err_free_id:
 	idr_remove(&root->cgroup_idr, cgrp->id);
-	/* Release the reference count that we took on the superblock */
-	deactivate_super(sb);
 err_unlock:
 	mutex_unlock(&cgroup_mutex);
-err_free_name:
-	kfree(rcu_dereference_raw(cgrp->name));
-err_free_cgrp:
+err_unlock_tree:
+	mutex_unlock(&cgroup_tree_mutex);
 	kfree(cgrp);
 	return err;
 
 err_destroy:
 	cgroup_destroy_locked(cgrp);
 	mutex_unlock(&cgroup_mutex);
-	mutex_unlock(&dentry->d_inode->i_mutex);
+	mutex_unlock(&cgroup_tree_mutex);
 	return err;
 }
 
-static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
+			umode_t mode)
 {
-	struct cgroup *c_parent = dentry->d_parent->d_fsdata;
+	struct cgroup *parent = parent_kn->priv;
+	int ret;
+
+	/*
+	 * cgroup_create() grabs cgroup_tree_mutex which nests outside
+	 * kernfs active_ref and cgroup_create() already synchronizes
+	 * properly against removal through cgroup_lock_live_group().
+	 * Break it before calling cgroup_create().
+	 */
+	cgroup_get(parent);
+	kernfs_break_active_protection(parent_kn);
+
+	ret = cgroup_create(parent, name, mode);
 
-	/* the vfs holds inode->i_mutex already */
-	return cgroup_create(c_parent, dentry, mode | S_IFDIR);
+	kernfs_unbreak_active_protection(parent_kn);
+	cgroup_put(parent);
+	return ret;
 }
 
 /*
@@ -4301,6 +3848,7 @@ static void css_killed_work_fn(struct work_struct *work)
 		container_of(work, struct cgroup_subsys_state, destroy_work);
 	struct cgroup *cgrp = css->cgroup;
 
+	mutex_lock(&cgroup_tree_mutex);
 	mutex_lock(&cgroup_mutex);
 
 	/*
@@ -4318,6 +3866,7 @@ static void css_killed_work_fn(struct work_struct *work)
 		cgroup_destroy_css_killed(cgrp);
 
 	mutex_unlock(&cgroup_mutex);
+	mutex_unlock(&cgroup_tree_mutex);
 
 	/*
 	 * Put the css refs from kill_css().  Each css holds an extra
@@ -4339,18 +3888,15 @@ static void css_killed_ref_fn(struct percpu_ref *ref)
 	queue_work(cgroup_destroy_wq, &css->destroy_work);
 }
 
-/**
- * kill_css - destroy a css
- * @css: css to destroy
- *
- * This function initiates destruction of @css by removing cgroup interface
- * files and putting its base reference.  ->css_offline() will be invoked
- * asynchronously once css_tryget() is guaranteed to fail and when the
- * reference count reaches zero, @css will be released.
- */
-static void kill_css(struct cgroup_subsys_state *css)
+static void __kill_css(struct cgroup_subsys_state *css)
 {
-	cgroup_clear_dir(css->cgroup, 1 << css->ss->subsys_id);
+	lockdep_assert_held(&cgroup_tree_mutex);
+
+	/*
+	 * This must happen before css is disassociated with its cgroup.
+	 * See seq_css() for details.
+	 */
+	cgroup_clear_dir(css->cgroup, 1 << css->ss->id);
 
 	/*
 	 * Killing would put the base ref, but we need to keep it alive
@@ -4372,6 +3918,28 @@ static void kill_css(struct cgroup_subsys_state *css)
 }
 
 /**
+ * kill_css - destroy a css
+ * @css: css to destroy
+ *
+ * This function initiates destruction of @css by removing cgroup interface
+ * files and putting its base reference.  ->css_offline() will be invoked
+ * asynchronously once css_tryget() is guaranteed to fail and when the
+ * reference count reaches zero, @css will be released.
+ */
+static void kill_css(struct cgroup_subsys_state *css)
+{
+	struct cgroup *cgrp = css->cgroup;
+
+	lockdep_assert_held(&cgroup_tree_mutex);
+
+	/* if already killed, noop */
+	if (cgrp->subsys_mask & (1 << css->ss->id)) {
+		cgrp->subsys_mask &= ~(1 << css->ss->id);
+		__kill_css(css);
+	}
+}
+
+/**
  * cgroup_destroy_locked - the first stage of cgroup destruction
  * @cgrp: cgroup to be destroyed
  *
@@ -4398,22 +3966,21 @@ static void kill_css(struct cgroup_subsys_state *css)
 static int cgroup_destroy_locked(struct cgroup *cgrp)
 	__releases(&cgroup_mutex) __acquires(&cgroup_mutex)
 {
-	struct dentry *d = cgrp->dentry;
-	struct cgroup_subsys_state *css;
 	struct cgroup *child;
+	struct cgroup_subsys_state *css;
 	bool empty;
 	int ssid;
 
-	lockdep_assert_held(&d->d_inode->i_mutex);
+	lockdep_assert_held(&cgroup_tree_mutex);
 	lockdep_assert_held(&cgroup_mutex);
 
 	/*
-	 * css_set_lock synchronizes access to ->cset_links and prevents
-	 * @cgrp from being removed while __put_css_set() is in progress.
+	 * css_set_rwsem synchronizes access to ->cset_links and prevents
+	 * @cgrp from being removed while put_css_set() is in progress.
 	 */
-	read_lock(&css_set_lock);
+	down_read(&css_set_rwsem);
 	empty = list_empty(&cgrp->cset_links);
-	read_unlock(&css_set_lock);
+	up_read(&css_set_rwsem);
 	if (!empty)
 		return -EBUSY;
 
@@ -4434,14 +4001,6 @@ static int cgroup_destroy_locked(struct cgroup *cgrp)
 		return -EBUSY;
 
 	/*
-	 * Initiate massacre of all css's.  cgroup_destroy_css_killed()
-	 * will be invoked to perform the rest of destruction once the
-	 * percpu refs of all css's are confirmed to be killed.
-	 */
-	for_each_css(css, ssid, cgrp)
-		kill_css(css);
-
-	/*
 	 * Mark @cgrp dead.  This prevents further task migration and child
 	 * creation by disabling cgroup_lock_live_group().  Note that
 	 * CGRP_DEAD assertion is depended upon by css_next_child() to
@@ -4450,6 +4009,17 @@ static int cgroup_destroy_locked(struct cgroup *cgrp)
 	 */
 	set_bit(CGRP_DEAD, &cgrp->flags);
 
+	/*
+	 * Initiate massacre of all css's.  cgroup_destroy_css_killed()
+	 * will be invoked to perform the rest of destruction once the
+	 * percpu refs of all css's are confirmed to be killed.  This
+	 * involves removing the subsystem's files, drop cgroup_mutex.
+	 */
+	mutex_unlock(&cgroup_mutex);
+	for_each_css(css, ssid, cgrp)
+		kill_css(css);
+	mutex_lock(&cgroup_mutex);
+
 	/* CGRP_DEAD is set, remove from ->release_list for the last time */
 	raw_spin_lock(&release_list_lock);
 	if (!list_empty(&cgrp->release_list))
@@ -4465,14 +4035,20 @@ static int cgroup_destroy_locked(struct cgroup *cgrp)
 	if (!cgrp->nr_css)
 		cgroup_destroy_css_killed(cgrp);
 
+	/* remove @cgrp directory along with the base files */
+	mutex_unlock(&cgroup_mutex);
+
 	/*
-	 * Clear the base files and remove @cgrp directory.  The removal
-	 * puts the base ref but we aren't quite done with @cgrp yet, so
-	 * hold onto it.
+	 * There are two control paths which try to determine cgroup from
+	 * dentry without going through kernfs - cgroupstats_build() and
+	 * css_tryget_from_dir().  Those are supported by RCU protecting
+	 * clearing of cgrp->kn->priv backpointer, which should happen
+	 * after all files under it have been removed.
 	 */
-	cgroup_addrm_files(cgrp, cgroup_base_files, false);
-	dget(d);
-	cgroup_d_remove_dir(d);
+	kernfs_remove(cgrp->kn);	/* @cgrp has an extra ref on its kn */
+	RCU_INIT_POINTER(*(void __rcu __force **)&cgrp->kn->priv, NULL);
+
+	mutex_lock(&cgroup_mutex);
 
 	return 0;
 };
@@ -4489,72 +4065,82 @@ static int cgroup_destroy_locked(struct cgroup *cgrp)
 static void cgroup_destroy_css_killed(struct cgroup *cgrp)
 {
 	struct cgroup *parent = cgrp->parent;
-	struct dentry *d = cgrp->dentry;
 
+	lockdep_assert_held(&cgroup_tree_mutex);
 	lockdep_assert_held(&cgroup_mutex);
 
 	/* delete this cgroup from parent->children */
 	list_del_rcu(&cgrp->sibling);
 
-	dput(d);
+	cgroup_put(cgrp);
 
 	set_bit(CGRP_RELEASABLE, &parent->flags);
 	check_for_release(parent);
 }
 
-static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry)
+static int cgroup_rmdir(struct kernfs_node *kn)
 {
-	int ret;
-
-	mutex_lock(&cgroup_mutex);
-	ret = cgroup_destroy_locked(dentry->d_fsdata);
-	mutex_unlock(&cgroup_mutex);
+	struct cgroup *cgrp = kn->priv;
+	int ret = 0;
 
-	return ret;
-}
+	/*
+	 * This is self-destruction but @kn can't be removed while this
+	 * callback is in progress.  Let's break active protection.  Once
+	 * the protection is broken, @cgrp can be destroyed at any point.
+	 * Pin it so that it stays accessible.
+	 */
+	cgroup_get(cgrp);
+	kernfs_break_active_protection(kn);
 
-static void __init_or_module cgroup_init_cftsets(struct cgroup_subsys *ss)
-{
-	INIT_LIST_HEAD(&ss->cftsets);
+	mutex_lock(&cgroup_tree_mutex);
+	mutex_lock(&cgroup_mutex);
 
 	/*
-	 * base_cftset is embedded in subsys itself, no need to worry about
-	 * deregistration.
+	 * @cgrp might already have been destroyed while we're trying to
+	 * grab the mutexes.
 	 */
-	if (ss->base_cftypes) {
-		struct cftype *cft;
+	if (!cgroup_is_dead(cgrp))
+		ret = cgroup_destroy_locked(cgrp);
 
-		for (cft = ss->base_cftypes; cft->name[0] != '\0'; cft++)
-			cft->ss = ss;
+	mutex_unlock(&cgroup_mutex);
+	mutex_unlock(&cgroup_tree_mutex);
 
-		ss->base_cftset.cfts = ss->base_cftypes;
-		list_add_tail(&ss->base_cftset.node, &ss->cftsets);
-	}
+	kernfs_unbreak_active_protection(kn);
+	cgroup_put(cgrp);
+	return ret;
 }
 
+static struct kernfs_syscall_ops cgroup_kf_syscall_ops = {
+	.remount_fs		= cgroup_remount,
+	.show_options		= cgroup_show_options,
+	.mkdir			= cgroup_mkdir,
+	.rmdir			= cgroup_rmdir,
+	.rename			= cgroup_rename,
+};
+
 static void __init cgroup_init_subsys(struct cgroup_subsys *ss)
 {
 	struct cgroup_subsys_state *css;
 
 	printk(KERN_INFO "Initializing cgroup subsys %s\n", ss->name);
 
+	mutex_lock(&cgroup_tree_mutex);
 	mutex_lock(&cgroup_mutex);
 
-	/* init base cftset */
-	cgroup_init_cftsets(ss);
+	INIT_LIST_HEAD(&ss->cfts);
 
-	/* Create the top cgroup state for this subsystem */
-	ss->root = &cgroup_dummy_root;
-	css = ss->css_alloc(cgroup_css(cgroup_dummy_top, ss));
+	/* Create the root cgroup state for this subsystem */
+	ss->root = &cgrp_dfl_root;
+	css = ss->css_alloc(cgroup_css(&cgrp_dfl_root.cgrp, ss));
 	/* We don't handle early failures gracefully */
 	BUG_ON(IS_ERR(css));
-	init_css(css, ss, cgroup_dummy_top);
+	init_css(css, ss, &cgrp_dfl_root.cgrp);
 
 	/* Update the init_css_set to contain a subsys
 	 * pointer to this state - since the subsystem is
 	 * newly registered, all tasks and hence the
-	 * init_css_set is in the subsystem's top cgroup. */
-	init_css_set.subsys[ss->subsys_id] = css;
+	 * init_css_set is in the subsystem's root cgroup. */
+	init_css_set.subsys[ss->id] = css;
 
 	need_forkexit_callback |= ss->fork || ss->exit;
 
@@ -4565,185 +4151,11 @@ static void __init cgroup_init_subsys(struct cgroup_subsys *ss)
 
 	BUG_ON(online_css(css));
 
-	mutex_unlock(&cgroup_mutex);
-
-	/* this function shouldn't be used with modular subsystems, since they
-	 * need to register a subsys_id, among other things */
-	BUG_ON(ss->module);
-}
-
-/**
- * cgroup_load_subsys: load and register a modular subsystem at runtime
- * @ss: the subsystem to load
- *
- * This function should be called in a modular subsystem's initcall. If the
- * subsystem is built as a module, it will be assigned a new subsys_id and set
- * up for use. If the subsystem is built-in anyway, work is delegated to the
- * simpler cgroup_init_subsys.
- */
-int __init_or_module cgroup_load_subsys(struct cgroup_subsys *ss)
-{
-	struct cgroup_subsys_state *css;
-	int i, ret;
-	struct hlist_node *tmp;
-	struct css_set *cset;
-	unsigned long key;
-
-	/* check name and function validity */
-	if (ss->name == NULL || strlen(ss->name) > MAX_CGROUP_TYPE_NAMELEN ||
-	    ss->css_alloc == NULL || ss->css_free == NULL)
-		return -EINVAL;
-
-	/*
-	 * we don't support callbacks in modular subsystems. this check is
-	 * before the ss->module check for consistency; a subsystem that could
-	 * be a module should still have no callbacks even if the user isn't
-	 * compiling it as one.
-	 */
-	if (ss->fork || ss->exit)
-		return -EINVAL;
-
-	/*
-	 * an optionally modular subsystem is built-in: we want to do nothing,
-	 * since cgroup_init_subsys will have already taken care of it.
-	 */
-	if (ss->module == NULL) {
-		/* a sanity check */
-		BUG_ON(cgroup_subsys[ss->subsys_id] != ss);
-		return 0;
-	}
-
-	/* init base cftset */
-	cgroup_init_cftsets(ss);
-
-	mutex_lock(&cgroup_mutex);
-	mutex_lock(&cgroup_root_mutex);
-	cgroup_subsys[ss->subsys_id] = ss;
-
-	/*
-	 * no ss->css_alloc seems to need anything important in the ss
-	 * struct, so this can happen first (i.e. before the dummy root
-	 * attachment).
-	 */
-	css = ss->css_alloc(cgroup_css(cgroup_dummy_top, ss));
-	if (IS_ERR(css)) {
-		/* failure case - need to deassign the cgroup_subsys[] slot. */
-		cgroup_subsys[ss->subsys_id] = NULL;
-		mutex_unlock(&cgroup_root_mutex);
-		mutex_unlock(&cgroup_mutex);
-		return PTR_ERR(css);
-	}
-
-	ss->root = &cgroup_dummy_root;
-
-	/* our new subsystem will be attached to the dummy hierarchy. */
-	init_css(css, ss, cgroup_dummy_top);
-
-	/*
-	 * Now we need to entangle the css into the existing css_sets. unlike
-	 * in cgroup_init_subsys, there are now multiple css_sets, so each one
-	 * will need a new pointer to it; done by iterating the css_set_table.
-	 * furthermore, modifying the existing css_sets will corrupt the hash
-	 * table state, so each changed css_set will need its hash recomputed.
-	 * this is all done under the css_set_lock.
-	 */
-	write_lock(&css_set_lock);
-	hash_for_each_safe(css_set_table, i, tmp, cset, hlist) {
-		/* skip entries that we already rehashed */
-		if (cset->subsys[ss->subsys_id])
-			continue;
-		/* remove existing entry */
-		hash_del(&cset->hlist);
-		/* set new value */
-		cset->subsys[ss->subsys_id] = css;
-		/* recompute hash and restore entry */
-		key = css_set_hash(cset->subsys);
-		hash_add(css_set_table, &cset->hlist, key);
-	}
-	write_unlock(&css_set_lock);
-
-	ret = online_css(css);
-	if (ret) {
-		ss->css_free(css);
-		goto err_unload;
-	}
-
-	/* success! */
-	mutex_unlock(&cgroup_root_mutex);
-	mutex_unlock(&cgroup_mutex);
-	return 0;
-
-err_unload:
-	mutex_unlock(&cgroup_root_mutex);
-	mutex_unlock(&cgroup_mutex);
-	/* @ss can't be mounted here as try_module_get() would fail */
-	cgroup_unload_subsys(ss);
-	return ret;
-}
-EXPORT_SYMBOL_GPL(cgroup_load_subsys);
-
-/**
- * cgroup_unload_subsys: unload a modular subsystem
- * @ss: the subsystem to unload
- *
- * This function should be called in a modular subsystem's exitcall. When this
- * function is invoked, the refcount on the subsystem's module will be 0, so
- * the subsystem will not be attached to any hierarchy.
- */
-void cgroup_unload_subsys(struct cgroup_subsys *ss)
-{
-	struct cgrp_cset_link *link;
-	struct cgroup_subsys_state *css;
-
-	BUG_ON(ss->module == NULL);
-
-	/*
-	 * we shouldn't be called if the subsystem is in use, and the use of
-	 * try_module_get() in rebind_subsystems() should ensure that it
-	 * doesn't start being used while we're killing it off.
-	 */
-	BUG_ON(ss->root != &cgroup_dummy_root);
-
-	mutex_lock(&cgroup_mutex);
-	mutex_lock(&cgroup_root_mutex);
-
-	css = cgroup_css(cgroup_dummy_top, ss);
-	if (css)
-		offline_css(css);
+	cgrp_dfl_root.cgrp.subsys_mask |= 1 << ss->id;
 
-	/* deassign the subsys_id */
-	cgroup_subsys[ss->subsys_id] = NULL;
-
-	/*
-	 * disentangle the css from all css_sets attached to the dummy
-	 * top. as in loading, we need to pay our respects to the hashtable
-	 * gods.
-	 */
-	write_lock(&css_set_lock);
-	list_for_each_entry(link, &cgroup_dummy_top->cset_links, cset_link) {
-		struct css_set *cset = link->cset;
-		unsigned long key;
-
-		hash_del(&cset->hlist);
-		cset->subsys[ss->subsys_id] = NULL;
-		key = css_set_hash(cset->subsys);
-		hash_add(css_set_table, &cset->hlist, key);
-	}
-	write_unlock(&css_set_lock);
-
-	/*
-	 * remove subsystem's css from the cgroup_dummy_top and free it -
-	 * need to free before marking as null because ss->css_free needs
-	 * the cgrp->subsys pointer to find their state.
-	 */
-	if (css)
-		ss->css_free(css);
-	RCU_INIT_POINTER(cgroup_dummy_top->subsys[ss->subsys_id], NULL);
-
-	mutex_unlock(&cgroup_root_mutex);
 	mutex_unlock(&cgroup_mutex);
+	mutex_unlock(&cgroup_tree_mutex);
 }
-EXPORT_SYMBOL_GPL(cgroup_unload_subsys);
 
 /**
  * cgroup_init_early - cgroup initialization at system boot
@@ -4753,34 +4165,24 @@ EXPORT_SYMBOL_GPL(cgroup_unload_subsys);
  */
 int __init cgroup_init_early(void)
 {
+	static struct cgroup_sb_opts __initdata opts =
+		{ .flags = CGRP_ROOT_SANE_BEHAVIOR };
 	struct cgroup_subsys *ss;
 	int i;
 
-	atomic_set(&init_css_set.refcount, 1);
-	INIT_LIST_HEAD(&init_css_set.cgrp_links);
-	INIT_LIST_HEAD(&init_css_set.tasks);
-	INIT_HLIST_NODE(&init_css_set.hlist);
-	css_set_count = 1;
-	init_cgroup_root(&cgroup_dummy_root);
-	cgroup_root_count = 1;
+	init_cgroup_root(&cgrp_dfl_root, &opts);
 	RCU_INIT_POINTER(init_task.cgroups, &init_css_set);
 
-	init_cgrp_cset_link.cset = &init_css_set;
-	init_cgrp_cset_link.cgrp = cgroup_dummy_top;
-	list_add(&init_cgrp_cset_link.cset_link, &cgroup_dummy_top->cset_links);
-	list_add(&init_cgrp_cset_link.cgrp_link, &init_css_set.cgrp_links);
-
-	/* at bootup time, we don't worry about modular subsystems */
-	for_each_builtin_subsys(ss, i) {
-		BUG_ON(!ss->name);
-		BUG_ON(strlen(ss->name) > MAX_CGROUP_TYPE_NAMELEN);
-		BUG_ON(!ss->css_alloc);
-		BUG_ON(!ss->css_free);
-		if (ss->subsys_id != i) {
-			printk(KERN_ERR "cgroup: Subsys %s id == %d\n",
-			       ss->name, ss->subsys_id);
-			BUG();
-		}
+	for_each_subsys(ss, i) {
+		WARN(!ss->css_alloc || !ss->css_free || ss->name || ss->id,
+		     "invalid cgroup_subsys %d:%s css_alloc=%p css_free=%p name:id=%d:%s\n",
+		     i, cgroup_subsys_name[i], ss->css_alloc, ss->css_free,
+		     ss->id, ss->name);
+		WARN(strlen(cgroup_subsys_name[i]) > MAX_CGROUP_TYPE_NAMELEN,
+		     "cgroup_subsys_name %s too long\n", cgroup_subsys_name[i]);
+
+		ss->id = i;
+		ss->name = cgroup_subsys_name[i];
 
 		if (ss->early_init)
 			cgroup_init_subsys(ss);
@@ -4798,53 +4200,46 @@ int __init cgroup_init(void)
 {
 	struct cgroup_subsys *ss;
 	unsigned long key;
-	int i, err;
+	int ssid, err;
 
-	err = bdi_init(&cgroup_backing_dev_info);
-	if (err)
-		return err;
+	BUG_ON(cgroup_init_cftypes(NULL, cgroup_base_files));
 
-	for_each_builtin_subsys(ss, i) {
-		if (!ss->early_init)
-			cgroup_init_subsys(ss);
-	}
-
-	/* allocate id for the dummy hierarchy */
+	mutex_lock(&cgroup_tree_mutex);
 	mutex_lock(&cgroup_mutex);
-	mutex_lock(&cgroup_root_mutex);
 
 	/* Add init_css_set to the hash table */
 	key = css_set_hash(init_css_set.subsys);
 	hash_add(css_set_table, &init_css_set.hlist, key);
 
-	BUG_ON(cgroup_init_root_id(&cgroup_dummy_root, 0, 1));
+	BUG_ON(cgroup_setup_root(&cgrp_dfl_root, 0));
 
-	err = idr_alloc(&cgroup_dummy_root.cgroup_idr, cgroup_dummy_top,
-			0, 1, GFP_KERNEL);
-	BUG_ON(err < 0);
-
-	mutex_unlock(&cgroup_root_mutex);
 	mutex_unlock(&cgroup_mutex);
+	mutex_unlock(&cgroup_tree_mutex);
 
-	cgroup_kobj = kobject_create_and_add("cgroup", fs_kobj);
-	if (!cgroup_kobj) {
-		err = -ENOMEM;
-		goto out;
+	for_each_subsys(ss, ssid) {
+		if (!ss->early_init)
+			cgroup_init_subsys(ss);
+
+		/*
+		 * cftype registration needs kmalloc and can't be done
+		 * during early_init.  Register base cftypes separately.
+		 */
+		if (ss->base_cftypes)
+			WARN_ON(cgroup_add_cftypes(ss, ss->base_cftypes));
 	}
 
+	cgroup_kobj = kobject_create_and_add("cgroup", fs_kobj);
+	if (!cgroup_kobj)
+		return -ENOMEM;
+
 	err = register_filesystem(&cgroup_fs_type);
 	if (err < 0) {
 		kobject_put(cgroup_kobj);
-		goto out;
+		return err;
 	}
 
 	proc_create("cgroups", 0, NULL, &proc_cgroupstats_operations);
-
-out:
-	if (err)
-		bdi_destroy(&cgroup_backing_dev_info);
-
-	return err;
+	return 0;
 }
 
 static int __init cgroup_wq_init(void)
@@ -4876,12 +4271,6 @@ core_initcall(cgroup_wq_init);
  * proc_cgroup_show()
  *  - Print task's cgroup paths into seq_file, one line for each hierarchy
  *  - Used for /proc/<pid>/cgroup.
- *  - No need to task_lock(tsk) on this tsk->cgroup reference, as it
- *    doesn't really matter if tsk->cgroup changes after we read it,
- *    and we take cgroup_mutex, keeping cgroup_attach_task() from changing it
- *    anyway.  No need to check that tsk->cgroup != NULL, thanks to
- *    the_top_cgroup_hack in cgroup_exit(), which sets an exiting tasks
- *    cgroup to top_cgroup.
  */
 
 /* TODO: Use a proper seq_file iterator */
@@ -4889,12 +4278,12 @@ int proc_cgroup_show(struct seq_file *m, void *v)
 {
 	struct pid *pid;
 	struct task_struct *tsk;
-	char *buf;
+	char *buf, *path;
 	int retval;
-	struct cgroupfs_root *root;
+	struct cgroup_root *root;
 
 	retval = -ENOMEM;
-	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	buf = kmalloc(PATH_MAX, GFP_KERNEL);
 	if (!buf)
 		goto out;
 
@@ -4907,29 +4296,36 @@ int proc_cgroup_show(struct seq_file *m, void *v)
 	retval = 0;
 
 	mutex_lock(&cgroup_mutex);
+	down_read(&css_set_rwsem);
 
-	for_each_active_root(root) {
+	for_each_root(root) {
 		struct cgroup_subsys *ss;
 		struct cgroup *cgrp;
 		int ssid, count = 0;
 
+		if (root == &cgrp_dfl_root && !cgrp_dfl_root_visible)
+			continue;
+
 		seq_printf(m, "%d:", root->hierarchy_id);
 		for_each_subsys(ss, ssid)
-			if (root->subsys_mask & (1 << ssid))
+			if (root->cgrp.subsys_mask & (1 << ssid))
 				seq_printf(m, "%s%s", count++ ? "," : "", ss->name);
 		if (strlen(root->name))
 			seq_printf(m, "%sname=%s", count ? "," : "",
 				   root->name);
 		seq_putc(m, ':');
 		cgrp = task_cgroup_from_root(tsk, root);
-		retval = cgroup_path(cgrp, buf, PAGE_SIZE);
-		if (retval < 0)
+		path = cgroup_path(cgrp, buf, PATH_MAX);
+		if (!path) {
+			retval = -ENAMETOOLONG;
 			goto out_unlock;
-		seq_puts(m, buf);
+		}
+		seq_puts(m, path);
 		seq_putc(m, '\n');
 	}
 
 out_unlock:
+	up_read(&css_set_rwsem);
 	mutex_unlock(&cgroup_mutex);
 	put_task_struct(tsk);
 out_free:
@@ -4955,7 +4351,7 @@ static int proc_cgroupstats_show(struct seq_file *m, void *v)
 	for_each_subsys(ss, i)
 		seq_printf(m, "%s\t%d\t%d\t%d\n",
 			   ss->name, ss->root->hierarchy_id,
-			   ss->root->number_of_cgroups, !ss->disabled);
+			   atomic_read(&ss->root->nr_cgrps), !ss->disabled);
 
 	mutex_unlock(&cgroup_mutex);
 	return 0;
@@ -4974,27 +4370,16 @@ static const struct file_operations proc_cgroupstats_operations = {
 };
 
 /**
- * cgroup_fork - attach newly forked task to its parents cgroup.
+ * cgroup_fork - initialize cgroup related fields during copy_process()
  * @child: pointer to task_struct of forking parent process.
  *
- * Description: A task inherits its parent's cgroup at fork().
- *
- * A pointer to the shared css_set was automatically copied in
- * fork.c by dup_task_struct().  However, we ignore that copy, since
- * it was not made under the protection of RCU or cgroup_mutex, so
- * might no longer be a valid cgroup pointer.  cgroup_attach_task() might
- * have already changed current->cgroups, allowing the previously
- * referenced cgroup group to be removed and freed.
- *
- * At the point that cgroup_fork() is called, 'current' is the parent
- * task, and the passed argument 'child' points to the child task.
+ * A task is associated with the init_css_set until cgroup_post_fork()
+ * attaches it to the parent's css_set.  Empty cg_list indicates that
+ * @child isn't holding reference to its css_set.
  */
 void cgroup_fork(struct task_struct *child)
 {
-	task_lock(current);
-	get_css_set(task_css_set(current));
-	child->cgroups = current->cgroups;
-	task_unlock(current);
+	RCU_INIT_POINTER(child->cgroups, &init_css_set);
 	INIT_LIST_HEAD(&child->cg_list);
 }
 
@@ -5014,23 +4399,37 @@ void cgroup_post_fork(struct task_struct *child)
 	int i;
 
 	/*
-	 * use_task_css_set_links is set to 1 before we walk the tasklist
-	 * under the tasklist_lock and we read it here after we added the child
-	 * to the tasklist under the tasklist_lock as well. If the child wasn't
-	 * yet in the tasklist when we walked through it from
-	 * cgroup_enable_task_cg_lists(), then use_task_css_set_links value
-	 * should be visible now due to the paired locking and barriers implied
-	 * by LOCK/UNLOCK: it is written before the tasklist_lock unlock
-	 * in cgroup_enable_task_cg_lists() and read here after the tasklist_lock
-	 * lock on fork.
+	 * This may race against cgroup_enable_task_cg_links().  As that
+	 * function sets use_task_css_set_links before grabbing
+	 * tasklist_lock and we just went through tasklist_lock to add
+	 * @child, it's guaranteed that either we see the set
+	 * use_task_css_set_links or cgroup_enable_task_cg_lists() sees
+	 * @child during its iteration.
+	 *
+	 * If we won the race, @child is associated with %current's
+	 * css_set.  Grabbing css_set_rwsem guarantees both that the
+	 * association is stable, and, on completion of the parent's
+	 * migration, @child is visible in the source of migration or
+	 * already in the destination cgroup.  This guarantee is necessary
+	 * when implementing operations which need to migrate all tasks of
+	 * a cgroup to another.
+	 *
+	 * Note that if we lose to cgroup_enable_task_cg_links(), @child
+	 * will remain in init_css_set.  This is safe because all tasks are
+	 * in the init_css_set before cg_links is enabled and there's no
+	 * operation which transfers all tasks out of init_css_set.
 	 */
 	if (use_task_css_set_links) {
-		write_lock(&css_set_lock);
-		task_lock(child);
-		if (list_empty(&child->cg_list))
-			list_add(&child->cg_list, &task_css_set(child)->tasks);
-		task_unlock(child);
-		write_unlock(&css_set_lock);
+		struct css_set *cset;
+
+		down_write(&css_set_rwsem);
+		cset = task_css_set(current);
+		if (list_empty(&child->cg_list)) {
+			rcu_assign_pointer(child->cgroups, cset);
+			list_add(&child->cg_list, &cset->tasks);
+			get_css_set(cset);
+		}
+		up_write(&css_set_rwsem);
 	}
 
 	/*
@@ -5039,15 +4438,7 @@ void cgroup_post_fork(struct task_struct *child)
 	 * and addition to css_set.
 	 */
 	if (need_forkexit_callback) {
-		/*
-		 * fork/exit callbacks are supported only for builtin
-		 * subsystems, and the builtin section of the subsys
-		 * array is immutable, so we don't need to lock the
-		 * subsys array here. On the other hand, modular section
-		 * of the array can be freed at module unload, so we
-		 * can't touch that.
-		 */
-		for_each_builtin_subsys(ss, i)
+		for_each_subsys(ss, i)
 			if (ss->fork)
 				ss->fork(child);
 	}
@@ -5056,7 +4447,6 @@ void cgroup_post_fork(struct task_struct *child)
 /**
  * cgroup_exit - detach cgroup from exiting task
  * @tsk: pointer to task_struct of exiting process
- * @run_callback: run exit callbacks?
  *
  * Description: Detach cgroup from @tsk and release it.
  *
@@ -5066,57 +4456,38 @@ void cgroup_post_fork(struct task_struct *child)
  * use notify_on_release cgroups where very high task exit scaling
  * is required on large systems.
  *
- * the_top_cgroup_hack:
- *
- *    Set the exiting tasks cgroup to the root cgroup (top_cgroup).
- *
- *    We call cgroup_exit() while the task is still competent to
- *    handle notify_on_release(), then leave the task attached to the
- *    root cgroup in each hierarchy for the remainder of its exit.
- *
- *    To do this properly, we would increment the reference count on
- *    top_cgroup, and near the very end of the kernel/exit.c do_exit()
- *    code we would add a second cgroup function call, to drop that
- *    reference.  This would just create an unnecessary hot spot on
- *    the top_cgroup reference count, to no avail.
- *
- *    Normally, holding a reference to a cgroup without bumping its
- *    count is unsafe.   The cgroup could go away, or someone could
- *    attach us to a different cgroup, decrementing the count on
- *    the first cgroup that we never incremented.  But in this case,
- *    top_cgroup isn't going away, and either task has PF_EXITING set,
- *    which wards off any cgroup_attach_task() attempts, or task is a failed
- *    fork, never visible to cgroup_attach_task.
+ * We set the exiting tasks cgroup to the root cgroup (top_cgroup).  We
+ * call cgroup_exit() while the task is still competent to handle
+ * notify_on_release(), then leave the task attached to the root cgroup in
+ * each hierarchy for the remainder of its exit.  No need to bother with
+ * init_css_set refcnting.  init_css_set never goes away and we can't race
+ * with migration path - PF_EXITING is visible to migration path.
  */
-void cgroup_exit(struct task_struct *tsk, int run_callbacks)
+void cgroup_exit(struct task_struct *tsk)
 {
 	struct cgroup_subsys *ss;
 	struct css_set *cset;
+	bool put_cset = false;
 	int i;
 
 	/*
-	 * Unlink from the css_set task list if necessary.
-	 * Optimistically check cg_list before taking
-	 * css_set_lock
+	 * Unlink from @tsk from its css_set.  As migration path can't race
+	 * with us, we can check cg_list without grabbing css_set_rwsem.
 	 */
 	if (!list_empty(&tsk->cg_list)) {
-		write_lock(&css_set_lock);
-		if (!list_empty(&tsk->cg_list))
-			list_del_init(&tsk->cg_list);
-		write_unlock(&css_set_lock);
+		down_write(&css_set_rwsem);
+		list_del_init(&tsk->cg_list);
+		up_write(&css_set_rwsem);
+		put_cset = true;
 	}
 
 	/* Reassign the task to the init_css_set. */
-	task_lock(tsk);
 	cset = task_css_set(tsk);
 	RCU_INIT_POINTER(tsk->cgroups, &init_css_set);
 
-	if (run_callbacks && need_forkexit_callback) {
-		/*
-		 * fork/exit callbacks are supported only for builtin
-		 * subsystems, see cgroup_post_fork() for details.
-		 */
-		for_each_builtin_subsys(ss, i) {
+	if (need_forkexit_callback) {
+		/* see cgroup_post_fork() for details */
+		for_each_subsys(ss, i) {
 			if (ss->exit) {
 				struct cgroup_subsys_state *old_css = cset->subsys[i];
 				struct cgroup_subsys_state *css = task_css(tsk, i);
@@ -5125,9 +4496,9 @@ void cgroup_exit(struct task_struct *tsk, int run_callbacks)
 			}
 		}
 	}
-	task_unlock(tsk);
 
-	put_css_set_taskexit(cset);
+	if (put_cset)
+		put_css_set(cset, true);
 }
 
 static void check_for_release(struct cgroup *cgrp)
@@ -5184,16 +4555,17 @@ static void cgroup_release_agent(struct work_struct *work)
 	while (!list_empty(&release_list)) {
 		char *argv[3], *envp[3];
 		int i;
-		char *pathbuf = NULL, *agentbuf = NULL;
+		char *pathbuf = NULL, *agentbuf = NULL, *path;
 		struct cgroup *cgrp = list_entry(release_list.next,
 						    struct cgroup,
 						    release_list);
 		list_del_init(&cgrp->release_list);
 		raw_spin_unlock(&release_list_lock);
-		pathbuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+		pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
 		if (!pathbuf)
 			goto continue_free;
-		if (cgroup_path(cgrp, pathbuf, PAGE_SIZE) < 0)
+		path = cgroup_path(cgrp, pathbuf, PATH_MAX);
+		if (!path)
 			goto continue_free;
 		agentbuf = kstrdup(cgrp->root->release_agent_path, GFP_KERNEL);
 		if (!agentbuf)
@@ -5201,7 +4573,7 @@ static void cgroup_release_agent(struct work_struct *work)
 
 		i = 0;
 		argv[i++] = agentbuf;
-		argv[i++] = pathbuf;
+		argv[i++] = path;
 		argv[i] = NULL;
 
 		i = 0;
@@ -5235,11 +4607,7 @@ static int __init cgroup_disable(char *str)
 		if (!*token)
 			continue;
 
-		/*
-		 * cgroup_disable, being at boot time, can't know about
-		 * module subsystems, so we don't worry about them.
-		 */
-		for_each_builtin_subsys(ss, i) {
+		for_each_subsys(ss, i) {
 			if (!strcmp(token, ss->name)) {
 				ss->disabled = 1;
 				printk(KERN_INFO "Disabling %s control group"
@@ -5253,28 +4621,42 @@ static int __init cgroup_disable(char *str)
 __setup("cgroup_disable=", cgroup_disable);
 
 /**
- * css_from_dir - get corresponding css from the dentry of a cgroup dir
+ * css_tryget_from_dir - get corresponding css from the dentry of a cgroup dir
  * @dentry: directory dentry of interest
  * @ss: subsystem of interest
  *
- * Must be called under cgroup_mutex or RCU read lock.  The caller is
- * responsible for pinning the returned css if it needs to be accessed
- * outside the critical section.
+ * If @dentry is a directory for a cgroup which has @ss enabled on it, try
+ * to get the corresponding css and return it.  If such css doesn't exist
+ * or can't be pinned, an ERR_PTR value is returned.
  */
-struct cgroup_subsys_state *css_from_dir(struct dentry *dentry,
-					 struct cgroup_subsys *ss)
+struct cgroup_subsys_state *css_tryget_from_dir(struct dentry *dentry,
+						struct cgroup_subsys *ss)
 {
+	struct kernfs_node *kn = kernfs_node_from_dentry(dentry);
+	struct cgroup_subsys_state *css = NULL;
 	struct cgroup *cgrp;
 
-	cgroup_assert_mutex_or_rcu_locked();
-
 	/* is @dentry a cgroup dir? */
-	if (!dentry->d_inode ||
-	    dentry->d_inode->i_op != &cgroup_dir_inode_operations)
+	if (dentry->d_sb->s_type != &cgroup_fs_type || !kn ||
+	    kernfs_type(kn) != KERNFS_DIR)
 		return ERR_PTR(-EBADF);
 
-	cgrp = __d_cgrp(dentry);
-	return cgroup_css(cgrp, ss) ?: ERR_PTR(-ENOENT);
+	rcu_read_lock();
+
+	/*
+	 * This path doesn't originate from kernfs and @kn could already
+	 * have been or be removed at any point.  @kn->priv is RCU
+	 * protected for this access.  See destroy_locked() for details.
+	 */
+	cgrp = rcu_dereference(kn->priv);
+	if (cgrp)
+		css = cgroup_css(cgrp, ss);
+
+	if (!css || !css_tryget(css))
+		css = ERR_PTR(-ENOENT);
+
+	rcu_read_unlock();
+	return css;
 }
 
 /**
@@ -5289,7 +4671,7 @@ struct cgroup_subsys_state *css_from_id(int id, struct cgroup_subsys *ss)
 {
 	struct cgroup *cgrp;
 
-	cgroup_assert_mutex_or_rcu_locked();
+	cgroup_assert_mutexes_or_rcu_locked();
 
 	cgrp = idr_find(&ss->root->cgroup_idr, id);
 	if (cgrp)
@@ -5341,23 +4723,25 @@ static int current_css_set_cg_links_read(struct seq_file *seq, void *v)
 {
 	struct cgrp_cset_link *link;
 	struct css_set *cset;
+	char *name_buf;
 
-	read_lock(&css_set_lock);
+	name_buf = kmalloc(NAME_MAX + 1, GFP_KERNEL);
+	if (!name_buf)
+		return -ENOMEM;
+
+	down_read(&css_set_rwsem);
 	rcu_read_lock();
 	cset = rcu_dereference(current->cgroups);
 	list_for_each_entry(link, &cset->cgrp_links, cgrp_link) {
 		struct cgroup *c = link->cgrp;
-		const char *name;
 
-		if (c->dentry)
-			name = c->dentry->d_name.name;
-		else
-			name = "?";
+		cgroup_name(c, name_buf, NAME_MAX + 1);
 		seq_printf(seq, "Root %d group %s\n",
-			   c->root->hierarchy_id, name);
+			   c->root->hierarchy_id, name_buf);
 	}
 	rcu_read_unlock();
-	read_unlock(&css_set_lock);
+	up_read(&css_set_rwsem);
+	kfree(name_buf);
 	return 0;
 }
 
@@ -5367,23 +4751,30 @@ static int cgroup_css_links_read(struct seq_file *seq, void *v)
 	struct cgroup_subsys_state *css = seq_css(seq);
 	struct cgrp_cset_link *link;
 
-	read_lock(&css_set_lock);
+	down_read(&css_set_rwsem);
 	list_for_each_entry(link, &css->cgroup->cset_links, cset_link) {
 		struct css_set *cset = link->cset;
 		struct task_struct *task;
 		int count = 0;
+
 		seq_printf(seq, "css_set %p\n", cset);
+
 		list_for_each_entry(task, &cset->tasks, cg_list) {
-			if (count++ > MAX_TASKS_SHOWN_PER_CSS) {
-				seq_puts(seq, "  ...\n");
-				break;
-			} else {
-				seq_printf(seq, "  task %d\n",
-					   task_pid_vnr(task));
-			}
+			if (count++ > MAX_TASKS_SHOWN_PER_CSS)
+				goto overflow;
+			seq_printf(seq, "  task %d\n", task_pid_vnr(task));
+		}
+
+		list_for_each_entry(task, &cset->mg_tasks, cg_list) {
+			if (count++ > MAX_TASKS_SHOWN_PER_CSS)
+				goto overflow;
+			seq_printf(seq, "  task %d\n", task_pid_vnr(task));
 		}
+		continue;
+	overflow:
+		seq_puts(seq, "  ...\n");
 	}
-	read_unlock(&css_set_lock);
+	up_read(&css_set_rwsem);
 	return 0;
 }
 
@@ -5426,11 +4817,9 @@ static struct cftype debug_files[] =  {
 	{ }	/* terminate */
 };
 
-struct cgroup_subsys debug_subsys = {
-	.name = "debug",
+struct cgroup_subsys debug_cgrp_subsys = {
 	.css_alloc = debug_css_alloc,
 	.css_free = debug_css_free,
-	.subsys_id = debug_subsys_id,
 	.base_cftypes = debug_files,
 };
 #endif /* CONFIG_CGROUP_DEBUG */
diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c
index 6c3154e477f6..345628c78b5b 100644
--- a/kernel/cgroup_freezer.c
+++ b/kernel/cgroup_freezer.c
@@ -21,6 +21,7 @@
 #include <linux/uaccess.h>
 #include <linux/freezer.h>
 #include <linux/seq_file.h>
+#include <linux/mutex.h>
 
 /*
  * A cgroup is freezing if any FREEZING flags are set.  FREEZING_SELF is
@@ -42,9 +43,10 @@ enum freezer_state_flags {
 struct freezer {
 	struct cgroup_subsys_state	css;
 	unsigned int			state;
-	spinlock_t			lock;
 };
 
+static DEFINE_MUTEX(freezer_mutex);
+
 static inline struct freezer *css_freezer(struct cgroup_subsys_state *css)
 {
 	return css ? container_of(css, struct freezer, css) : NULL;
@@ -52,7 +54,7 @@ static inline struct freezer *css_freezer(struct cgroup_subsys_state *css)
 
 static inline struct freezer *task_freezer(struct task_struct *task)
 {
-	return css_freezer(task_css(task, freezer_subsys_id));
+	return css_freezer(task_css(task, freezer_cgrp_id));
 }
 
 static struct freezer *parent_freezer(struct freezer *freezer)
@@ -84,8 +86,6 @@ static const char *freezer_state_strs(unsigned int state)
 	return "THAWED";
 };
 
-struct cgroup_subsys freezer_subsys;
-
 static struct cgroup_subsys_state *
 freezer_css_alloc(struct cgroup_subsys_state *parent_css)
 {
@@ -95,7 +95,6 @@ freezer_css_alloc(struct cgroup_subsys_state *parent_css)
 	if (!freezer)
 		return ERR_PTR(-ENOMEM);
 
-	spin_lock_init(&freezer->lock);
 	return &freezer->css;
 }
 
@@ -112,14 +111,7 @@ static int freezer_css_online(struct cgroup_subsys_state *css)
 	struct freezer *freezer = css_freezer(css);
 	struct freezer *parent = parent_freezer(freezer);
 
-	/*
-	 * The following double locking and freezing state inheritance
-	 * guarantee that @cgroup can never escape ancestors' freezing
-	 * states.  See css_for_each_descendant_pre() for details.
-	 */
-	if (parent)
-		spin_lock_irq(&parent->lock);
-	spin_lock_nested(&freezer->lock, SINGLE_DEPTH_NESTING);
+	mutex_lock(&freezer_mutex);
 
 	freezer->state |= CGROUP_FREEZER_ONLINE;
 
@@ -128,10 +120,7 @@ static int freezer_css_online(struct cgroup_subsys_state *css)
 		atomic_inc(&system_freezing_cnt);
 	}
 
-	spin_unlock(&freezer->lock);
-	if (parent)
-		spin_unlock_irq(&parent->lock);
-
+	mutex_unlock(&freezer_mutex);
 	return 0;
 }
 
@@ -146,14 +135,14 @@ static void freezer_css_offline(struct cgroup_subsys_state *css)
 {
 	struct freezer *freezer = css_freezer(css);
 
-	spin_lock_irq(&freezer->lock);
+	mutex_lock(&freezer_mutex);
 
 	if (freezer->state & CGROUP_FREEZING)
 		atomic_dec(&system_freezing_cnt);
 
 	freezer->state = 0;
 
-	spin_unlock_irq(&freezer->lock);
+	mutex_unlock(&freezer_mutex);
 }
 
 static void freezer_css_free(struct cgroup_subsys_state *css)
@@ -177,7 +166,7 @@ static void freezer_attach(struct cgroup_subsys_state *new_css,
 	struct task_struct *task;
 	bool clear_frozen = false;
 
-	spin_lock_irq(&freezer->lock);
+	mutex_lock(&freezer_mutex);
 
 	/*
 	 * Make the new tasks conform to the current state of @new_css.
@@ -189,7 +178,7 @@ static void freezer_attach(struct cgroup_subsys_state *new_css,
 	 * current state before executing the following - !frozen tasks may
 	 * be visible in a FROZEN cgroup and frozen tasks in a THAWED one.
 	 */
-	cgroup_taskset_for_each(task, new_css, tset) {
+	cgroup_taskset_for_each(task, tset) {
 		if (!(freezer->state & CGROUP_FREEZING)) {
 			__thaw_task(task);
 		} else {
@@ -199,43 +188,48 @@ static void freezer_attach(struct cgroup_subsys_state *new_css,
 		}
 	}
 
-	spin_unlock_irq(&freezer->lock);
-
-	/*
-	 * Propagate FROZEN clearing upwards.  We may race with
-	 * update_if_frozen(), but as long as both work bottom-up, either
-	 * update_if_frozen() sees child's FROZEN cleared or we clear the
-	 * parent's FROZEN later.  No parent w/ !FROZEN children can be
-	 * left FROZEN.
-	 */
+	/* propagate FROZEN clearing upwards */
 	while (clear_frozen && (freezer = parent_freezer(freezer))) {
-		spin_lock_irq(&freezer->lock);
 		freezer->state &= ~CGROUP_FROZEN;
 		clear_frozen = freezer->state & CGROUP_FREEZING;
-		spin_unlock_irq(&freezer->lock);
 	}
+
+	mutex_unlock(&freezer_mutex);
 }
 
+/**
+ * freezer_fork - cgroup post fork callback
+ * @task: a task which has just been forked
+ *
+ * @task has just been created and should conform to the current state of
+ * the cgroup_freezer it belongs to.  This function may race against
+ * freezer_attach().  Losing to freezer_attach() means that we don't have
+ * to do anything as freezer_attach() will put @task into the appropriate
+ * state.
+ */
 static void freezer_fork(struct task_struct *task)
 {
 	struct freezer *freezer;
 
-	rcu_read_lock();
-	freezer = task_freezer(task);
-
 	/*
-	 * The root cgroup is non-freezable, so we can skip the
-	 * following check.
+	 * The root cgroup is non-freezable, so we can skip locking the
+	 * freezer.  This is safe regardless of race with task migration.
+	 * If we didn't race or won, skipping is obviously the right thing
+	 * to do.  If we lost and root is the new cgroup, noop is still the
+	 * right thing to do.
 	 */
-	if (!parent_freezer(freezer))
-		goto out;
+	if (task_css_is_root(task, freezer_cgrp_id))
+		return;
 
-	spin_lock_irq(&freezer->lock);
+	mutex_lock(&freezer_mutex);
+	rcu_read_lock();
+
+	freezer = task_freezer(task);
 	if (freezer->state & CGROUP_FREEZING)
 		freeze_task(task);
-	spin_unlock_irq(&freezer->lock);
-out:
+
 	rcu_read_unlock();
+	mutex_unlock(&freezer_mutex);
 }
 
 /**
@@ -261,22 +255,24 @@ static void update_if_frozen(struct cgroup_subsys_state *css)
 	struct css_task_iter it;
 	struct task_struct *task;
 
-	WARN_ON_ONCE(!rcu_read_lock_held());
-
-	spin_lock_irq(&freezer->lock);
+	lockdep_assert_held(&freezer_mutex);
 
 	if (!(freezer->state & CGROUP_FREEZING) ||
 	    (freezer->state & CGROUP_FROZEN))
-		goto out_unlock;
+		return;
 
 	/* are all (live) children frozen? */
+	rcu_read_lock();
 	css_for_each_child(pos, css) {
 		struct freezer *child = css_freezer(pos);
 
 		if ((child->state & CGROUP_FREEZER_ONLINE) &&
-		    !(child->state & CGROUP_FROZEN))
-			goto out_unlock;
+		    !(child->state & CGROUP_FROZEN)) {
+			rcu_read_unlock();
+			return;
+		}
 	}
+	rcu_read_unlock();
 
 	/* are all tasks frozen? */
 	css_task_iter_start(css, &it);
@@ -297,21 +293,29 @@ static void update_if_frozen(struct cgroup_subsys_state *css)
 	freezer->state |= CGROUP_FROZEN;
 out_iter_end:
 	css_task_iter_end(&it);
-out_unlock:
-	spin_unlock_irq(&freezer->lock);
 }
 
 static int freezer_read(struct seq_file *m, void *v)
 {
 	struct cgroup_subsys_state *css = seq_css(m), *pos;
 
+	mutex_lock(&freezer_mutex);
 	rcu_read_lock();
 
 	/* update states bottom-up */
-	css_for_each_descendant_post(pos, css)
+	css_for_each_descendant_post(pos, css) {
+		if (!css_tryget(pos))
+			continue;
+		rcu_read_unlock();
+
 		update_if_frozen(pos);
 
+		rcu_read_lock();
+		css_put(pos);
+	}
+
 	rcu_read_unlock();
+	mutex_unlock(&freezer_mutex);
 
 	seq_puts(m, freezer_state_strs(css_freezer(css)->state));
 	seq_putc(m, '\n');
@@ -353,7 +357,7 @@ static void freezer_apply_state(struct freezer *freezer, bool freeze,
 				unsigned int state)
 {
 	/* also synchronizes against task migration, see freezer_attach() */
-	lockdep_assert_held(&freezer->lock);
+	lockdep_assert_held(&freezer_mutex);
 
 	if (!(freezer->state & CGROUP_FREEZER_ONLINE))
 		return;
@@ -394,35 +398,33 @@ static void freezer_change_state(struct freezer *freezer, bool freeze)
 	 * descendant will try to inherit its parent's FREEZING state as
 	 * CGROUP_FREEZING_PARENT.
 	 */
+	mutex_lock(&freezer_mutex);
 	rcu_read_lock();
 	css_for_each_descendant_pre(pos, &freezer->css) {
 		struct freezer *pos_f = css_freezer(pos);
 		struct freezer *parent = parent_freezer(pos_f);
 
-		spin_lock_irq(&pos_f->lock);
+		if (!css_tryget(pos))
+			continue;
+		rcu_read_unlock();
 
-		if (pos_f == freezer) {
+		if (pos_f == freezer)
 			freezer_apply_state(pos_f, freeze,
 					    CGROUP_FREEZING_SELF);
-		} else {
-			/*
-			 * Our update to @parent->state is already visible
-			 * which is all we need.  No need to lock @parent.
-			 * For more info on synchronization, see
-			 * freezer_post_create().
-			 */
+		else
 			freezer_apply_state(pos_f,
 					    parent->state & CGROUP_FREEZING,
 					    CGROUP_FREEZING_PARENT);
-		}
 
-		spin_unlock_irq(&pos_f->lock);
+		rcu_read_lock();
+		css_put(pos);
 	}
 	rcu_read_unlock();
+	mutex_unlock(&freezer_mutex);
 }
 
 static int freezer_write(struct cgroup_subsys_state *css, struct cftype *cft,
-			 const char *buffer)
+			 char *buffer)
 {
 	bool freeze;
 
@@ -473,13 +475,11 @@ static struct cftype files[] = {
 	{ }	/* terminate */
 };
 
-struct cgroup_subsys freezer_subsys = {
-	.name		= "freezer",
+struct cgroup_subsys freezer_cgrp_subsys = {
 	.css_alloc	= freezer_css_alloc,
 	.css_online	= freezer_css_online,
 	.css_offline	= freezer_css_offline,
 	.css_free	= freezer_css_free,
-	.subsys_id	= freezer_subsys_id,
 	.attach		= freezer_attach,
 	.fork		= freezer_fork,
 	.base_cftypes	= files,
diff --git a/kernel/compat.c b/kernel/compat.c
index 0a09e481b70b..e40b0430b562 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -30,28 +30,6 @@
 
 #include <asm/uaccess.h>
 
-/*
- * Get/set struct timeval with struct timespec on the native side
- */
-static int compat_get_timeval_convert(struct timespec *o,
-				      struct compat_timeval __user *i)
-{
-	long usec;
-
-	if (get_user(o->tv_sec, &i->tv_sec) ||
-	    get_user(usec, &i->tv_usec))
-		return -EFAULT;
-	o->tv_nsec = usec * 1000;
-	return 0;
-}
-
-static int compat_put_timeval_convert(struct compat_timeval __user *o,
-				      struct timeval *i)
-{
-	return (put_user(i->tv_sec, &o->tv_sec) ||
-		put_user(i->tv_usec, &o->tv_usec)) ? -EFAULT : 0;
-}
-
 static int compat_get_timex(struct timex *txc, struct compat_timex __user *utp)
 {
 	memset(txc, 0, sizeof(struct timex));
@@ -110,13 +88,13 @@ static int compat_put_timex(struct compat_timex __user *utp, struct timex *txc)
 	return 0;
 }
 
-asmlinkage long compat_sys_gettimeofday(struct compat_timeval __user *tv,
-		struct timezone __user *tz)
+COMPAT_SYSCALL_DEFINE2(gettimeofday, struct compat_timeval __user *, tv,
+		       struct timezone __user *, tz)
 {
 	if (tv) {
 		struct timeval ktv;
 		do_gettimeofday(&ktv);
-		if (compat_put_timeval_convert(tv, &ktv))
+		if (compat_put_timeval(&ktv, tv))
 			return -EFAULT;
 	}
 	if (tz) {
@@ -127,62 +105,61 @@ asmlinkage long compat_sys_gettimeofday(struct compat_timeval __user *tv,
 	return 0;
 }
 
-asmlinkage long compat_sys_settimeofday(struct compat_timeval __user *tv,
-		struct timezone __user *tz)
+COMPAT_SYSCALL_DEFINE2(settimeofday, struct compat_timeval __user *, tv,
+		       struct timezone __user *, tz)
 {
-	struct timespec kts;
-	struct timezone ktz;
+	struct timeval user_tv;
+	struct timespec	new_ts;
+	struct timezone new_tz;
 
 	if (tv) {
-		if (compat_get_timeval_convert(&kts, tv))
+		if (compat_get_timeval(&user_tv, tv))
 			return -EFAULT;
+		new_ts.tv_sec = user_tv.tv_sec;
+		new_ts.tv_nsec = user_tv.tv_usec * NSEC_PER_USEC;
 	}
 	if (tz) {
-		if (copy_from_user(&ktz, tz, sizeof(ktz)))
+		if (copy_from_user(&new_tz, tz, sizeof(*tz)))
 			return -EFAULT;
 	}
 
-	return do_sys_settimeofday(tv ? &kts : NULL, tz ? &ktz : NULL);
+	return do_sys_settimeofday(tv ? &new_ts : NULL, tz ? &new_tz : NULL);
 }
 
-int get_compat_timeval(struct timeval *tv, const struct compat_timeval __user *ctv)
+static int __compat_get_timeval(struct timeval *tv, const struct compat_timeval __user *ctv)
 {
 	return (!access_ok(VERIFY_READ, ctv, sizeof(*ctv)) ||
 			__get_user(tv->tv_sec, &ctv->tv_sec) ||
 			__get_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
 }
-EXPORT_SYMBOL_GPL(get_compat_timeval);
 
-int put_compat_timeval(const struct timeval *tv, struct compat_timeval __user *ctv)
+static int __compat_put_timeval(const struct timeval *tv, struct compat_timeval __user *ctv)
 {
 	return (!access_ok(VERIFY_WRITE, ctv, sizeof(*ctv)) ||
 			__put_user(tv->tv_sec, &ctv->tv_sec) ||
 			__put_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
 }
-EXPORT_SYMBOL_GPL(put_compat_timeval);
 
-int get_compat_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
+static int __compat_get_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
 {
 	return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
 			__get_user(ts->tv_sec, &cts->tv_sec) ||
 			__get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
 }
-EXPORT_SYMBOL_GPL(get_compat_timespec);
 
-int put_compat_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
+static int __compat_put_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
 {
 	return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
 			__put_user(ts->tv_sec, &cts->tv_sec) ||
 			__put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
 }
-EXPORT_SYMBOL_GPL(put_compat_timespec);
 
 int compat_get_timeval(struct timeval *tv, const void __user *utv)
 {
 	if (COMPAT_USE_64BIT_TIME)
 		return copy_from_user(tv, utv, sizeof *tv) ? -EFAULT : 0;
 	else
-		return get_compat_timeval(tv, utv);
+		return __compat_get_timeval(tv, utv);
 }
 EXPORT_SYMBOL_GPL(compat_get_timeval);
 
@@ -191,7 +168,7 @@ int compat_put_timeval(const struct timeval *tv, void __user *utv)
 	if (COMPAT_USE_64BIT_TIME)
 		return copy_to_user(utv, tv, sizeof *tv) ? -EFAULT : 0;
 	else
-		return put_compat_timeval(tv, utv);
+		return __compat_put_timeval(tv, utv);
 }
 EXPORT_SYMBOL_GPL(compat_put_timeval);
 
@@ -200,7 +177,7 @@ int compat_get_timespec(struct timespec *ts, const void __user *uts)
 	if (COMPAT_USE_64BIT_TIME)
 		return copy_from_user(ts, uts, sizeof *ts) ? -EFAULT : 0;
 	else
-		return get_compat_timespec(ts, uts);
+		return __compat_get_timespec(ts, uts);
 }
 EXPORT_SYMBOL_GPL(compat_get_timespec);
 
@@ -209,10 +186,33 @@ int compat_put_timespec(const struct timespec *ts, void __user *uts)
 	if (COMPAT_USE_64BIT_TIME)
 		return copy_to_user(uts, ts, sizeof *ts) ? -EFAULT : 0;
 	else
-		return put_compat_timespec(ts, uts);
+		return __compat_put_timespec(ts, uts);
 }
 EXPORT_SYMBOL_GPL(compat_put_timespec);
 
+int compat_convert_timespec(struct timespec __user **kts,
+			    const void __user *cts)
+{
+	struct timespec ts;
+	struct timespec __user *uts;
+
+	if (!cts || COMPAT_USE_64BIT_TIME) {
+		*kts = (struct timespec __user *)cts;
+		return 0;
+	}
+
+	uts = compat_alloc_user_space(sizeof(ts));
+	if (!uts)
+		return -EFAULT;
+	if (compat_get_timespec(&ts, cts))
+		return -EFAULT;
+	if (copy_to_user(uts, &ts, sizeof(ts)))
+		return -EFAULT;
+
+	*kts = uts;
+	return 0;
+}
+
 static long compat_nanosleep_restart(struct restart_block *restart)
 {
 	struct compat_timespec __user *rmtp;
@@ -229,21 +229,21 @@ static long compat_nanosleep_restart(struct restart_block *restart)
 	if (ret) {
 		rmtp = restart->nanosleep.compat_rmtp;
 
-		if (rmtp && put_compat_timespec(&rmt, rmtp))
+		if (rmtp && compat_put_timespec(&rmt, rmtp))
 			return -EFAULT;
 	}
 
 	return ret;
 }
 
-asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
-				     struct compat_timespec __user *rmtp)
+COMPAT_SYSCALL_DEFINE2(nanosleep, struct compat_timespec __user *, rqtp,
+		       struct compat_timespec __user *, rmtp)
 {
 	struct timespec tu, rmt;
 	mm_segment_t oldfs;
 	long ret;
 
-	if (get_compat_timespec(&tu, rqtp))
+	if (compat_get_timespec(&tu, rqtp))
 		return -EFAULT;
 
 	if (!timespec_valid(&tu))
@@ -263,7 +263,7 @@ asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
 		restart->fn = compat_nanosleep_restart;
 		restart->nanosleep.compat_rmtp = rmtp;
 
-		if (rmtp && put_compat_timespec(&rmt, rmtp))
+		if (rmtp && compat_put_timespec(&rmt, rmtp))
 			return -EFAULT;
 	}
 
@@ -328,7 +328,7 @@ static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
 	return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
 }
 
-asmlinkage long compat_sys_times(struct compat_tms __user *tbuf)
+COMPAT_SYSCALL_DEFINE1(times, struct compat_tms __user *, tbuf)
 {
 	if (tbuf) {
 		struct tms tms;
@@ -354,7 +354,7 @@ asmlinkage long compat_sys_times(struct compat_tms __user *tbuf)
  * types that can be passed to put_user()/get_user().
  */
 
-asmlinkage long compat_sys_sigpending(compat_old_sigset_t __user *set)
+COMPAT_SYSCALL_DEFINE1(sigpending, compat_old_sigset_t __user *, set)
 {
 	old_sigset_t s;
 	long ret;
@@ -424,8 +424,8 @@ COMPAT_SYSCALL_DEFINE3(sigprocmask, int, how,
 
 #endif
 
-asmlinkage long compat_sys_setrlimit(unsigned int resource,
-		struct compat_rlimit __user *rlim)
+COMPAT_SYSCALL_DEFINE2(setrlimit, unsigned int, resource,
+		       struct compat_rlimit __user *, rlim)
 {
 	struct rlimit r;
 
@@ -443,15 +443,15 @@ asmlinkage long compat_sys_setrlimit(unsigned int resource,
 
 #ifdef COMPAT_RLIM_OLD_INFINITY
 
-asmlinkage long compat_sys_old_getrlimit(unsigned int resource,
-		struct compat_rlimit __user *rlim)
+COMPAT_SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
+		       struct compat_rlimit __user *, rlim)
 {
 	struct rlimit r;
 	int ret;
 	mm_segment_t old_fs = get_fs();
 
 	set_fs(KERNEL_DS);
-	ret = sys_old_getrlimit(resource, &r);
+	ret = sys_old_getrlimit(resource, (struct rlimit __user *)&r);
 	set_fs(old_fs);
 
 	if (!ret) {
@@ -470,8 +470,8 @@ asmlinkage long compat_sys_old_getrlimit(unsigned int resource,
 
 #endif
 
-asmlinkage long compat_sys_getrlimit(unsigned int resource,
-		struct compat_rlimit __user *rlim)
+COMPAT_SYSCALL_DEFINE2(getrlimit, unsigned int, resource,
+		       struct compat_rlimit __user *, rlim)
 {
 	struct rlimit r;
 	int ret;
@@ -596,9 +596,9 @@ static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
 	return compat_get_bitmap(k, user_mask_ptr, len * 8);
 }
 
-asmlinkage long compat_sys_sched_setaffinity(compat_pid_t pid,
-					     unsigned int len,
-					     compat_ulong_t __user *user_mask_ptr)
+COMPAT_SYSCALL_DEFINE3(sched_setaffinity, compat_pid_t, pid,
+		       unsigned int, len,
+		       compat_ulong_t __user *, user_mask_ptr)
 {
 	cpumask_var_t new_mask;
 	int retval;
@@ -616,8 +616,8 @@ out:
 	return retval;
 }
 
-asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
-					     compat_ulong_t __user *user_mask_ptr)
+COMPAT_SYSCALL_DEFINE3(sched_getaffinity, compat_pid_t,  pid, unsigned int, len,
+		       compat_ulong_t __user *, user_mask_ptr)
 {
 	int ret;
 	cpumask_var_t mask;
@@ -647,8 +647,8 @@ asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
 int get_compat_itimerspec(struct itimerspec *dst,
 			  const struct compat_itimerspec __user *src)
 {
-	if (get_compat_timespec(&dst->it_interval, &src->it_interval) ||
-	    get_compat_timespec(&dst->it_value, &src->it_value))
+	if (__compat_get_timespec(&dst->it_interval, &src->it_interval) ||
+	    __compat_get_timespec(&dst->it_value, &src->it_value))
 		return -EFAULT;
 	return 0;
 }
@@ -656,15 +656,15 @@ int get_compat_itimerspec(struct itimerspec *dst,
 int put_compat_itimerspec(struct compat_itimerspec __user *dst,
 			  const struct itimerspec *src)
 {
-	if (put_compat_timespec(&src->it_interval, &dst->it_interval) ||
-	    put_compat_timespec(&src->it_value, &dst->it_value))
+	if (__compat_put_timespec(&src->it_interval, &dst->it_interval) ||
+	    __compat_put_timespec(&src->it_value, &dst->it_value))
 		return -EFAULT;
 	return 0;
 }
 
-long compat_sys_timer_create(clockid_t which_clock,
-			struct compat_sigevent __user *timer_event_spec,
-			timer_t __user *created_timer_id)
+COMPAT_SYSCALL_DEFINE3(timer_create, clockid_t, which_clock,
+		       struct compat_sigevent __user *, timer_event_spec,
+		       timer_t __user *, created_timer_id)
 {
 	struct sigevent __user *event = NULL;
 
@@ -680,9 +680,9 @@ long compat_sys_timer_create(clockid_t which_clock,
 	return sys_timer_create(which_clock, event, created_timer_id);
 }
 
-long compat_sys_timer_settime(timer_t timer_id, int flags,
-			  struct compat_itimerspec __user *new,
-			  struct compat_itimerspec __user *old)
+COMPAT_SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags,
+		       struct compat_itimerspec __user *, new,
+		       struct compat_itimerspec __user *, old)
 {
 	long err;
 	mm_segment_t oldfs;
@@ -703,8 +703,8 @@ long compat_sys_timer_settime(timer_t timer_id, int flags,
 	return err;
 }
 
-long compat_sys_timer_gettime(timer_t timer_id,
-		struct compat_itimerspec __user *setting)
+COMPAT_SYSCALL_DEFINE2(timer_gettime, timer_t, timer_id,
+		       struct compat_itimerspec __user *, setting)
 {
 	long err;
 	mm_segment_t oldfs;
@@ -720,14 +720,14 @@ long compat_sys_timer_gettime(timer_t timer_id,
 	return err;
 }
 
-long compat_sys_clock_settime(clockid_t which_clock,
-		struct compat_timespec __user *tp)
+COMPAT_SYSCALL_DEFINE2(clock_settime, clockid_t, which_clock,
+		       struct compat_timespec __user *, tp)
 {
 	long err;
 	mm_segment_t oldfs;
 	struct timespec ts;
 
-	if (get_compat_timespec(&ts, tp))
+	if (compat_get_timespec(&ts, tp))
 		return -EFAULT;
 	oldfs = get_fs();
 	set_fs(KERNEL_DS);
@@ -737,8 +737,8 @@ long compat_sys_clock_settime(clockid_t which_clock,
 	return err;
 }
 
-long compat_sys_clock_gettime(clockid_t which_clock,
-		struct compat_timespec __user *tp)
+COMPAT_SYSCALL_DEFINE2(clock_gettime, clockid_t, which_clock,
+		       struct compat_timespec __user *, tp)
 {
 	long err;
 	mm_segment_t oldfs;
@@ -749,13 +749,13 @@ long compat_sys_clock_gettime(clockid_t which_clock,
 	err = sys_clock_gettime(which_clock,
 				(struct timespec __user *) &ts);
 	set_fs(oldfs);
-	if (!err && put_compat_timespec(&ts, tp))
+	if (!err && compat_put_timespec(&ts, tp))
 		return -EFAULT;
 	return err;
 }
 
-long compat_sys_clock_adjtime(clockid_t which_clock,
-		struct compat_timex __user *utp)
+COMPAT_SYSCALL_DEFINE2(clock_adjtime, clockid_t, which_clock,
+		       struct compat_timex __user *, utp)
 {
 	struct timex txc;
 	mm_segment_t oldfs;
@@ -777,8 +777,8 @@ long compat_sys_clock_adjtime(clockid_t which_clock,
 	return ret;
 }
 
-long compat_sys_clock_getres(clockid_t which_clock,
-		struct compat_timespec __user *tp)
+COMPAT_SYSCALL_DEFINE2(clock_getres, clockid_t, which_clock,
+		       struct compat_timespec __user *, tp)
 {
 	long err;
 	mm_segment_t oldfs;
@@ -789,7 +789,7 @@ long compat_sys_clock_getres(clockid_t which_clock,
 	err = sys_clock_getres(which_clock,
 			       (struct timespec __user *) &ts);
 	set_fs(oldfs);
-	if (!err && tp && put_compat_timespec(&ts, tp))
+	if (!err && tp && compat_put_timespec(&ts, tp))
 		return -EFAULT;
 	return err;
 }
@@ -799,7 +799,7 @@ static long compat_clock_nanosleep_restart(struct restart_block *restart)
 	long err;
 	mm_segment_t oldfs;
 	struct timespec tu;
-	struct compat_timespec *rmtp = restart->nanosleep.compat_rmtp;
+	struct compat_timespec __user *rmtp = restart->nanosleep.compat_rmtp;
 
 	restart->nanosleep.rmtp = (struct timespec __user *) &tu;
 	oldfs = get_fs();
@@ -808,7 +808,7 @@ static long compat_clock_nanosleep_restart(struct restart_block *restart)
 	set_fs(oldfs);
 
 	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
-	    put_compat_timespec(&tu, rmtp))
+	    compat_put_timespec(&tu, rmtp))
 		return -EFAULT;
 
 	if (err == -ERESTART_RESTARTBLOCK) {
@@ -818,16 +818,16 @@ static long compat_clock_nanosleep_restart(struct restart_block *restart)
 	return err;
 }
 
-long compat_sys_clock_nanosleep(clockid_t which_clock, int flags,
-			    struct compat_timespec __user *rqtp,
-			    struct compat_timespec __user *rmtp)
+COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags,
+		       struct compat_timespec __user *, rqtp,
+		       struct compat_timespec __user *, rmtp)
 {
 	long err;
 	mm_segment_t oldfs;
 	struct timespec in, out;
 	struct restart_block *restart;
 
-	if (get_compat_timespec(&in, rqtp))
+	if (compat_get_timespec(&in, rqtp))
 		return -EFAULT;
 
 	oldfs = get_fs();
@@ -838,7 +838,7 @@ long compat_sys_clock_nanosleep(clockid_t which_clock, int flags,
 	set_fs(oldfs);
 
 	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
-	    put_compat_timespec(&out, rmtp))
+	    compat_put_timespec(&out, rmtp))
 		return -EFAULT;
 
 	if (err == -ERESTART_RESTARTBLOCK) {
@@ -1010,7 +1010,7 @@ COMPAT_SYSCALL_DEFINE4(rt_sigtimedwait, compat_sigset_t __user *, uthese,
 
 /* compat_time_t is a 32 bit "long" and needs to get converted. */
 
-asmlinkage long compat_sys_time(compat_time_t __user * tloc)
+COMPAT_SYSCALL_DEFINE1(time, compat_time_t __user *, tloc)
 {
 	compat_time_t i;
 	struct timeval tv;
@@ -1026,7 +1026,7 @@ asmlinkage long compat_sys_time(compat_time_t __user * tloc)
 	return i;
 }
 
-asmlinkage long compat_sys_stime(compat_time_t __user *tptr)
+COMPAT_SYSCALL_DEFINE1(stime, compat_time_t __user *, tptr)
 {
 	struct timespec tv;
 	int err;
@@ -1046,7 +1046,7 @@ asmlinkage long compat_sys_stime(compat_time_t __user *tptr)
 
 #endif /* __ARCH_WANT_COMPAT_SYS_TIME */
 
-asmlinkage long compat_sys_adjtimex(struct compat_timex __user *utp)
+COMPAT_SYSCALL_DEFINE1(adjtimex, struct compat_timex __user *, utp)
 {
 	struct timex txc;
 	int err, ret;
@@ -1065,11 +1065,11 @@ asmlinkage long compat_sys_adjtimex(struct compat_timex __user *utp)
 }
 
 #ifdef CONFIG_NUMA
-asmlinkage long compat_sys_move_pages(pid_t pid, unsigned long nr_pages,
-		compat_uptr_t __user *pages32,
-		const int __user *nodes,
-		int __user *status,
-		int flags)
+COMPAT_SYSCALL_DEFINE6(move_pages, pid_t, pid, compat_ulong_t, nr_pages,
+		       compat_uptr_t __user *, pages32,
+		       const int __user *, nodes,
+		       int __user *, status,
+		       int, flags)
 {
 	const void __user * __user *pages;
 	int i;
@@ -1085,10 +1085,10 @@ asmlinkage long compat_sys_move_pages(pid_t pid, unsigned long nr_pages,
 	return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
 }
 
-asmlinkage long compat_sys_migrate_pages(compat_pid_t pid,
-			compat_ulong_t maxnode,
-			const compat_ulong_t __user *old_nodes,
-			const compat_ulong_t __user *new_nodes)
+COMPAT_SYSCALL_DEFINE4(migrate_pages, compat_pid_t, pid,
+		       compat_ulong_t, maxnode,
+		       const compat_ulong_t __user *, old_nodes,
+		       const compat_ulong_t __user *, new_nodes)
 {
 	unsigned long __user *old = NULL;
 	unsigned long __user *new = NULL;
@@ -1130,7 +1130,7 @@ COMPAT_SYSCALL_DEFINE2(sched_rr_get_interval,
 	set_fs(KERNEL_DS);
 	ret = sys_sched_rr_get_interval(pid, (struct timespec __user *)&t);
 	set_fs(old_fs);
-	if (put_compat_timespec(&t, interval))
+	if (compat_put_timespec(&t, interval))
 		return -EFAULT;
 	return ret;
 }
diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c
index 6cb20d2e7ee0..019d45008448 100644
--- a/kernel/context_tracking.c
+++ b/kernel/context_tracking.c
@@ -120,7 +120,7 @@ void context_tracking_user_enter(void)
  * instead of preempt_schedule() to exit user context if needed before
  * calling the scheduler.
  */
-asmlinkage void __sched notrace preempt_schedule_context(void)
+asmlinkage __visible void __sched notrace preempt_schedule_context(void)
 {
 	enum ctx_state prev_ctx;
 
diff --git a/kernel/cpu.c b/kernel/cpu.c
index deff2e693766..247979a1b815 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -19,6 +19,7 @@
 #include <linux/mutex.h>
 #include <linux/gfp.h>
 #include <linux/suspend.h>
+#include <linux/lockdep.h>
 
 #include "smpboot.h"
 
@@ -27,18 +28,23 @@
 static DEFINE_MUTEX(cpu_add_remove_lock);
 
 /*
- * The following two API's must be used when attempting
- * to serialize the updates to cpu_online_mask, cpu_present_mask.
+ * The following two APIs (cpu_maps_update_begin/done) must be used when
+ * attempting to serialize the updates to cpu_online_mask & cpu_present_mask.
+ * The APIs cpu_notifier_register_begin/done() must be used to protect CPU
+ * hotplug callback (un)registration performed using __register_cpu_notifier()
+ * or __unregister_cpu_notifier().
  */
 void cpu_maps_update_begin(void)
 {
 	mutex_lock(&cpu_add_remove_lock);
 }
+EXPORT_SYMBOL(cpu_notifier_register_begin);
 
 void cpu_maps_update_done(void)
 {
 	mutex_unlock(&cpu_add_remove_lock);
 }
+EXPORT_SYMBOL(cpu_notifier_register_done);
 
 static RAW_NOTIFIER_HEAD(cpu_chain);
 
@@ -57,17 +63,30 @@ static struct {
 	 * an ongoing cpu hotplug operation.
 	 */
 	int refcount;
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	struct lockdep_map dep_map;
+#endif
 } cpu_hotplug = {
 	.active_writer = NULL,
 	.lock = __MUTEX_INITIALIZER(cpu_hotplug.lock),
 	.refcount = 0,
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	.dep_map = {.name = "cpu_hotplug.lock" },
+#endif
 };
 
+/* Lockdep annotations for get/put_online_cpus() and cpu_hotplug_begin/end() */
+#define cpuhp_lock_acquire_read() lock_map_acquire_read(&cpu_hotplug.dep_map)
+#define cpuhp_lock_acquire()      lock_map_acquire(&cpu_hotplug.dep_map)
+#define cpuhp_lock_release()      lock_map_release(&cpu_hotplug.dep_map)
+
 void get_online_cpus(void)
 {
 	might_sleep();
 	if (cpu_hotplug.active_writer == current)
 		return;
+	cpuhp_lock_acquire_read();
 	mutex_lock(&cpu_hotplug.lock);
 	cpu_hotplug.refcount++;
 	mutex_unlock(&cpu_hotplug.lock);
@@ -87,6 +106,7 @@ void put_online_cpus(void)
 	if (!--cpu_hotplug.refcount && unlikely(cpu_hotplug.active_writer))
 		wake_up_process(cpu_hotplug.active_writer);
 	mutex_unlock(&cpu_hotplug.lock);
+	cpuhp_lock_release();
 
 }
 EXPORT_SYMBOL_GPL(put_online_cpus);
@@ -117,6 +137,7 @@ void cpu_hotplug_begin(void)
 {
 	cpu_hotplug.active_writer = current;
 
+	cpuhp_lock_acquire();
 	for (;;) {
 		mutex_lock(&cpu_hotplug.lock);
 		if (likely(!cpu_hotplug.refcount))
@@ -131,6 +152,7 @@ void cpu_hotplug_done(void)
 {
 	cpu_hotplug.active_writer = NULL;
 	mutex_unlock(&cpu_hotplug.lock);
+	cpuhp_lock_release();
 }
 
 /*
@@ -166,6 +188,11 @@ int __ref register_cpu_notifier(struct notifier_block *nb)
 	return ret;
 }
 
+int __ref __register_cpu_notifier(struct notifier_block *nb)
+{
+	return raw_notifier_chain_register(&cpu_chain, nb);
+}
+
 static int __cpu_notify(unsigned long val, void *v, int nr_to_call,
 			int *nr_calls)
 {
@@ -189,6 +216,7 @@ static void cpu_notify_nofail(unsigned long val, void *v)
 	BUG_ON(cpu_notify(val, v));
 }
 EXPORT_SYMBOL(register_cpu_notifier);
+EXPORT_SYMBOL(__register_cpu_notifier);
 
 void __ref unregister_cpu_notifier(struct notifier_block *nb)
 {
@@ -198,6 +226,12 @@ void __ref unregister_cpu_notifier(struct notifier_block *nb)
 }
 EXPORT_SYMBOL(unregister_cpu_notifier);
 
+void __ref __unregister_cpu_notifier(struct notifier_block *nb)
+{
+	raw_notifier_chain_unregister(&cpu_chain, nb);
+}
+EXPORT_SYMBOL(__unregister_cpu_notifier);
+
 /**
  * clear_tasks_mm_cpumask - Safely clear tasks' mm_cpumask for a CPU
  * @cpu: a CPU id
@@ -692,10 +726,12 @@ void set_cpu_present(unsigned int cpu, bool present)
 
 void set_cpu_online(unsigned int cpu, bool online)
 {
-	if (online)
+	if (online) {
 		cpumask_set_cpu(cpu, to_cpumask(cpu_online_bits));
-	else
+		cpumask_set_cpu(cpu, to_cpumask(cpu_active_bits));
+	} else {
 		cpumask_clear_cpu(cpu, to_cpumask(cpu_online_bits));
+	}
 }
 
 void set_cpu_active(unsigned int cpu, bool active)
diff --git a/kernel/cpu/Makefile b/kernel/cpu/Makefile
deleted file mode 100644
index 59ab052ef7a0..000000000000
--- a/kernel/cpu/Makefile
+++ /dev/null
@@ -1 +0,0 @@
-obj-y	= idle.o
diff --git a/kernel/cpu/idle.c b/kernel/cpu/idle.c
deleted file mode 100644
index 277f494c2a9a..000000000000
--- a/kernel/cpu/idle.c
+++ /dev/null
@@ -1,144 +0,0 @@
-/*
- * Generic entry point for the idle threads
- */
-#include <linux/sched.h>
-#include <linux/cpu.h>
-#include <linux/tick.h>
-#include <linux/mm.h>
-#include <linux/stackprotector.h>
-
-#include <asm/tlb.h>
-
-#include <trace/events/power.h>
-
-static int __read_mostly cpu_idle_force_poll;
-
-void cpu_idle_poll_ctrl(bool enable)
-{
-	if (enable) {
-		cpu_idle_force_poll++;
-	} else {
-		cpu_idle_force_poll--;
-		WARN_ON_ONCE(cpu_idle_force_poll < 0);
-	}
-}
-
-#ifdef CONFIG_GENERIC_IDLE_POLL_SETUP
-static int __init cpu_idle_poll_setup(char *__unused)
-{
-	cpu_idle_force_poll = 1;
-	return 1;
-}
-__setup("nohlt", cpu_idle_poll_setup);
-
-static int __init cpu_idle_nopoll_setup(char *__unused)
-{
-	cpu_idle_force_poll = 0;
-	return 1;
-}
-__setup("hlt", cpu_idle_nopoll_setup);
-#endif
-
-static inline int cpu_idle_poll(void)
-{
-	rcu_idle_enter();
-	trace_cpu_idle_rcuidle(0, smp_processor_id());
-	local_irq_enable();
-	while (!tif_need_resched())
-		cpu_relax();
-	trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id());
-	rcu_idle_exit();
-	return 1;
-}
-
-/* Weak implementations for optional arch specific functions */
-void __weak arch_cpu_idle_prepare(void) { }
-void __weak arch_cpu_idle_enter(void) { }
-void __weak arch_cpu_idle_exit(void) { }
-void __weak arch_cpu_idle_dead(void) { }
-void __weak arch_cpu_idle(void)
-{
-	cpu_idle_force_poll = 1;
-	local_irq_enable();
-}
-
-/*
- * Generic idle loop implementation
- */
-static void cpu_idle_loop(void)
-{
-	while (1) {
-		tick_nohz_idle_enter();
-
-		while (!need_resched()) {
-			check_pgt_cache();
-			rmb();
-
-			if (cpu_is_offline(smp_processor_id()))
-				arch_cpu_idle_dead();
-
-			local_irq_disable();
-			arch_cpu_idle_enter();
-
-			/*
-			 * In poll mode we reenable interrupts and spin.
-			 *
-			 * Also if we detected in the wakeup from idle
-			 * path that the tick broadcast device expired
-			 * for us, we don't want to go deep idle as we
-			 * know that the IPI is going to arrive right
-			 * away
-			 */
-			if (cpu_idle_force_poll || tick_check_broadcast_expired()) {
-				cpu_idle_poll();
-			} else {
-				if (!current_clr_polling_and_test()) {
-					stop_critical_timings();
-					rcu_idle_enter();
-					arch_cpu_idle();
-					WARN_ON_ONCE(irqs_disabled());
-					rcu_idle_exit();
-					start_critical_timings();
-				} else {
-					local_irq_enable();
-				}
-				__current_set_polling();
-			}
-			arch_cpu_idle_exit();
-		}
-
-		/*
-		 * Since we fell out of the loop above, we know
-		 * TIF_NEED_RESCHED must be set, propagate it into
-		 * PREEMPT_NEED_RESCHED.
-		 *
-		 * This is required because for polling idle loops we will
-		 * not have had an IPI to fold the state for us.
-		 */
-		preempt_set_need_resched();
-		tick_nohz_idle_exit();
-		schedule_preempt_disabled();
-	}
-}
-
-void cpu_startup_entry(enum cpuhp_state state)
-{
-	/*
-	 * This #ifdef needs to die, but it's too late in the cycle to
-	 * make this generic (arm and sh have never invoked the canary
-	 * init for the non boot cpus!). Will be fixed in 3.11
-	 */
-#ifdef CONFIG_X86
-	/*
-	 * If we're the non-boot CPU, nothing set the stack canary up
-	 * for us. The boot CPU already has it initialized but no harm
-	 * in doing it again. This is a good place for updating it, as
-	 * we wont ever return from this function (so the invalid
-	 * canaries already on the stack wont ever trigger).
-	 */
-	boot_init_stack_canary();
-#endif
-	__current_set_polling();
-	arch_cpu_idle_prepare();
-	cpu_idle_loop();
-}
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index e6b1b66afe52..3d54c418bd06 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -119,7 +119,7 @@ static inline struct cpuset *css_cs(struct cgroup_subsys_state *css)
 /* Retrieve the cpuset for a task */
 static inline struct cpuset *task_cs(struct task_struct *task)
 {
-	return css_cs(task_css(task, cpuset_subsys_id));
+	return css_cs(task_css(task, cpuset_cgrp_id));
 }
 
 static inline struct cpuset *parent_cs(struct cpuset *cs)
@@ -467,7 +467,7 @@ static int validate_change(struct cpuset *cur, struct cpuset *trial)
 	 * be changed to have empty cpus_allowed or mems_allowed.
 	 */
 	ret = -ENOSPC;
-	if ((cgroup_task_count(cur->css.cgroup) || cur->attach_in_progress)) {
+	if ((cgroup_has_tasks(cur->css.cgroup) || cur->attach_in_progress)) {
 		if (!cpumask_empty(cur->cpus_allowed) &&
 		    cpumask_empty(trial->cpus_allowed))
 			goto out;
@@ -829,55 +829,36 @@ static struct cpuset *effective_nodemask_cpuset(struct cpuset *cs)
 }
 
 /**
- * cpuset_change_cpumask - make a task's cpus_allowed the same as its cpuset's
- * @tsk: task to test
- * @data: cpuset to @tsk belongs to
- *
- * Called by css_scan_tasks() for each task in a cgroup whose cpus_allowed
- * mask needs to be changed.
- *
- * We don't need to re-check for the cgroup/cpuset membership, since we're
- * holding cpuset_mutex at this point.
- */
-static void cpuset_change_cpumask(struct task_struct *tsk, void *data)
-{
-	struct cpuset *cs = data;
-	struct cpuset *cpus_cs = effective_cpumask_cpuset(cs);
-
-	set_cpus_allowed_ptr(tsk, cpus_cs->cpus_allowed);
-}
-
-/**
  * update_tasks_cpumask - Update the cpumasks of tasks in the cpuset.
  * @cs: the cpuset in which each task's cpus_allowed mask needs to be changed
- * @heap: if NULL, defer allocating heap memory to css_scan_tasks()
- *
- * Called with cpuset_mutex held
  *
- * The css_scan_tasks() function will scan all the tasks in a cgroup,
- * calling callback functions for each.
- *
- * No return value. It's guaranteed that css_scan_tasks() always returns 0
- * if @heap != NULL.
+ * Iterate through each task of @cs updating its cpus_allowed to the
+ * effective cpuset's.  As this function is called with cpuset_mutex held,
+ * cpuset membership stays stable.
  */
-static void update_tasks_cpumask(struct cpuset *cs, struct ptr_heap *heap)
+static void update_tasks_cpumask(struct cpuset *cs)
 {
-	css_scan_tasks(&cs->css, NULL, cpuset_change_cpumask, cs, heap);
+	struct cpuset *cpus_cs = effective_cpumask_cpuset(cs);
+	struct css_task_iter it;
+	struct task_struct *task;
+
+	css_task_iter_start(&cs->css, &it);
+	while ((task = css_task_iter_next(&it)))
+		set_cpus_allowed_ptr(task, cpus_cs->cpus_allowed);
+	css_task_iter_end(&it);
 }
 
 /*
  * update_tasks_cpumask_hier - Update the cpumasks of tasks in the hierarchy.
  * @root_cs: the root cpuset of the hierarchy
  * @update_root: update root cpuset or not?
- * @heap: the heap used by css_scan_tasks()
  *
  * This will update cpumasks of tasks in @root_cs and all other empty cpusets
  * which take on cpumask of @root_cs.
  *
  * Called with cpuset_mutex held
  */
-static void update_tasks_cpumask_hier(struct cpuset *root_cs,
-				      bool update_root, struct ptr_heap *heap)
+static void update_tasks_cpumask_hier(struct cpuset *root_cs, bool update_root)
 {
 	struct cpuset *cp;
 	struct cgroup_subsys_state *pos_css;
@@ -898,7 +879,7 @@ static void update_tasks_cpumask_hier(struct cpuset *root_cs,
 			continue;
 		rcu_read_unlock();
 
-		update_tasks_cpumask(cp, heap);
+		update_tasks_cpumask(cp);
 
 		rcu_read_lock();
 		css_put(&cp->css);
@@ -914,7 +895,6 @@ static void update_tasks_cpumask_hier(struct cpuset *root_cs,
 static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
 			  const char *buf)
 {
-	struct ptr_heap heap;
 	int retval;
 	int is_load_balanced;
 
@@ -947,19 +927,13 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
 	if (retval < 0)
 		return retval;
 
-	retval = heap_init(&heap, PAGE_SIZE, GFP_KERNEL, NULL);
-	if (retval)
-		return retval;
-
 	is_load_balanced = is_sched_load_balance(trialcs);
 
 	mutex_lock(&callback_mutex);
 	cpumask_copy(cs->cpus_allowed, trialcs->cpus_allowed);
 	mutex_unlock(&callback_mutex);
 
-	update_tasks_cpumask_hier(cs, true, &heap);
-
-	heap_free(&heap);
+	update_tasks_cpumask_hier(cs, true);
 
 	if (is_load_balanced)
 		rebuild_sched_domains_locked();
@@ -1022,7 +996,7 @@ static void cpuset_change_task_nodemask(struct task_struct *tsk,
 	task_lock(tsk);
 	/*
 	 * Determine if a loop is necessary if another thread is doing
-	 * get_mems_allowed().  If at least one node remains unchanged and
+	 * read_mems_allowed_begin().  If at least one node remains unchanged and
 	 * tsk does not have a mempolicy, then an empty nodemask will not be
 	 * possible when mems_allowed is larger than a word.
 	 */
@@ -1048,53 +1022,22 @@ static void cpuset_change_task_nodemask(struct task_struct *tsk,
 	task_unlock(tsk);
 }
 
-struct cpuset_change_nodemask_arg {
-	struct cpuset		*cs;
-	nodemask_t		*newmems;
-};
-
-/*
- * Update task's mems_allowed and rebind its mempolicy and vmas' mempolicy
- * of it to cpuset's new mems_allowed, and migrate pages to new nodes if
- * memory_migrate flag is set. Called with cpuset_mutex held.
- */
-static void cpuset_change_nodemask(struct task_struct *p, void *data)
-{
-	struct cpuset_change_nodemask_arg *arg = data;
-	struct cpuset *cs = arg->cs;
-	struct mm_struct *mm;
-	int migrate;
-
-	cpuset_change_task_nodemask(p, arg->newmems);
-
-	mm = get_task_mm(p);
-	if (!mm)
-		return;
-
-	migrate = is_memory_migrate(cs);
-
-	mpol_rebind_mm(mm, &cs->mems_allowed);
-	if (migrate)
-		cpuset_migrate_mm(mm, &cs->old_mems_allowed, arg->newmems);
-	mmput(mm);
-}
-
 static void *cpuset_being_rebound;
 
 /**
  * update_tasks_nodemask - Update the nodemasks of tasks in the cpuset.
  * @cs: the cpuset in which each task's mems_allowed mask needs to be changed
- * @heap: if NULL, defer allocating heap memory to css_scan_tasks()
  *
- * Called with cpuset_mutex held.  No return value. It's guaranteed that
- * css_scan_tasks() always returns 0 if @heap != NULL.
+ * Iterate through each task of @cs updating its mems_allowed to the
+ * effective cpuset's.  As this function is called with cpuset_mutex held,
+ * cpuset membership stays stable.
  */
-static void update_tasks_nodemask(struct cpuset *cs, struct ptr_heap *heap)
+static void update_tasks_nodemask(struct cpuset *cs)
 {
 	static nodemask_t newmems;	/* protected by cpuset_mutex */
 	struct cpuset *mems_cs = effective_nodemask_cpuset(cs);
-	struct cpuset_change_nodemask_arg arg = { .cs = cs,
-						  .newmems = &newmems };
+	struct css_task_iter it;
+	struct task_struct *task;
 
 	cpuset_being_rebound = cs;		/* causes mpol_dup() rebind */
 
@@ -1110,7 +1053,25 @@ static void update_tasks_nodemask(struct cpuset *cs, struct ptr_heap *heap)
 	 * It's ok if we rebind the same mm twice; mpol_rebind_mm()
 	 * is idempotent.  Also migrate pages in each mm to new nodes.
 	 */
-	css_scan_tasks(&cs->css, NULL, cpuset_change_nodemask, &arg, heap);
+	css_task_iter_start(&cs->css, &it);
+	while ((task = css_task_iter_next(&it))) {
+		struct mm_struct *mm;
+		bool migrate;
+
+		cpuset_change_task_nodemask(task, &newmems);
+
+		mm = get_task_mm(task);
+		if (!mm)
+			continue;
+
+		migrate = is_memory_migrate(cs);
+
+		mpol_rebind_mm(mm, &cs->mems_allowed);
+		if (migrate)
+			cpuset_migrate_mm(mm, &cs->old_mems_allowed, &newmems);
+		mmput(mm);
+	}
+	css_task_iter_end(&it);
 
 	/*
 	 * All the tasks' nodemasks have been updated, update
@@ -1126,15 +1087,13 @@ static void update_tasks_nodemask(struct cpuset *cs, struct ptr_heap *heap)
  * update_tasks_nodemask_hier - Update the nodemasks of tasks in the hierarchy.
  * @cs: the root cpuset of the hierarchy
  * @update_root: update the root cpuset or not?
- * @heap: the heap used by css_scan_tasks()
  *
  * This will update nodemasks of tasks in @root_cs and all other empty cpusets
  * which take on nodemask of @root_cs.
  *
  * Called with cpuset_mutex held
  */
-static void update_tasks_nodemask_hier(struct cpuset *root_cs,
-				       bool update_root, struct ptr_heap *heap)
+static void update_tasks_nodemask_hier(struct cpuset *root_cs, bool update_root)
 {
 	struct cpuset *cp;
 	struct cgroup_subsys_state *pos_css;
@@ -1155,7 +1114,7 @@ static void update_tasks_nodemask_hier(struct cpuset *root_cs,
 			continue;
 		rcu_read_unlock();
 
-		update_tasks_nodemask(cp, heap);
+		update_tasks_nodemask(cp);
 
 		rcu_read_lock();
 		css_put(&cp->css);
@@ -1180,7 +1139,6 @@ static int update_nodemask(struct cpuset *cs, struct cpuset *trialcs,
 			   const char *buf)
 {
 	int retval;
-	struct ptr_heap heap;
 
 	/*
 	 * top_cpuset.mems_allowed tracks node_stats[N_MEMORY];
@@ -1219,17 +1177,11 @@ static int update_nodemask(struct cpuset *cs, struct cpuset *trialcs,
 	if (retval < 0)
 		goto done;
 
-	retval = heap_init(&heap, PAGE_SIZE, GFP_KERNEL, NULL);
-	if (retval < 0)
-		goto done;
-
 	mutex_lock(&callback_mutex);
 	cs->mems_allowed = trialcs->mems_allowed;
 	mutex_unlock(&callback_mutex);
 
-	update_tasks_nodemask_hier(cs, true, &heap);
-
-	heap_free(&heap);
+	update_tasks_nodemask_hier(cs, true);
 done:
 	return retval;
 }
@@ -1257,38 +1209,22 @@ static int update_relax_domain_level(struct cpuset *cs, s64 val)
 }
 
 /**
- * cpuset_change_flag - make a task's spread flags the same as its cpuset's
- * @tsk: task to be updated
- * @data: cpuset to @tsk belongs to
- *
- * Called by css_scan_tasks() for each task in a cgroup.
- *
- * We don't need to re-check for the cgroup/cpuset membership, since we're
- * holding cpuset_mutex at this point.
- */
-static void cpuset_change_flag(struct task_struct *tsk, void *data)
-{
-	struct cpuset *cs = data;
-
-	cpuset_update_task_spread_flag(cs, tsk);
-}
-
-/**
  * update_tasks_flags - update the spread flags of tasks in the cpuset.
  * @cs: the cpuset in which each task's spread flags needs to be changed
- * @heap: if NULL, defer allocating heap memory to css_scan_tasks()
- *
- * Called with cpuset_mutex held
  *
- * The css_scan_tasks() function will scan all the tasks in a cgroup,
- * calling callback functions for each.
- *
- * No return value. It's guaranteed that css_scan_tasks() always returns 0
- * if @heap != NULL.
+ * Iterate through each task of @cs updating its spread flags.  As this
+ * function is called with cpuset_mutex held, cpuset membership stays
+ * stable.
  */
-static void update_tasks_flags(struct cpuset *cs, struct ptr_heap *heap)
+static void update_tasks_flags(struct cpuset *cs)
 {
-	css_scan_tasks(&cs->css, NULL, cpuset_change_flag, cs, heap);
+	struct css_task_iter it;
+	struct task_struct *task;
+
+	css_task_iter_start(&cs->css, &it);
+	while ((task = css_task_iter_next(&it)))
+		cpuset_update_task_spread_flag(cs, task);
+	css_task_iter_end(&it);
 }
 
 /*
@@ -1306,7 +1242,6 @@ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
 	struct cpuset *trialcs;
 	int balance_flag_changed;
 	int spread_flag_changed;
-	struct ptr_heap heap;
 	int err;
 
 	trialcs = alloc_trial_cpuset(cs);
@@ -1322,10 +1257,6 @@ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
 	if (err < 0)
 		goto out;
 
-	err = heap_init(&heap, PAGE_SIZE, GFP_KERNEL, NULL);
-	if (err < 0)
-		goto out;
-
 	balance_flag_changed = (is_sched_load_balance(cs) !=
 				is_sched_load_balance(trialcs));
 
@@ -1340,8 +1271,7 @@ static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs,
 		rebuild_sched_domains_locked();
 
 	if (spread_flag_changed)
-		update_tasks_flags(cs, &heap);
-	heap_free(&heap);
+		update_tasks_flags(cs);
 out:
 	free_trial_cpuset(trialcs);
 	return err;
@@ -1445,6 +1375,8 @@ static int fmeter_getrate(struct fmeter *fmp)
 	return val;
 }
 
+static struct cpuset *cpuset_attach_old_cs;
+
 /* Called by cgroups to determine if a cpuset is usable; cpuset_mutex held */
 static int cpuset_can_attach(struct cgroup_subsys_state *css,
 			     struct cgroup_taskset *tset)
@@ -1453,6 +1385,9 @@ static int cpuset_can_attach(struct cgroup_subsys_state *css,
 	struct task_struct *task;
 	int ret;
 
+	/* used later by cpuset_attach() */
+	cpuset_attach_old_cs = task_cs(cgroup_taskset_first(tset));
+
 	mutex_lock(&cpuset_mutex);
 
 	/*
@@ -1464,7 +1399,7 @@ static int cpuset_can_attach(struct cgroup_subsys_state *css,
 	    (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed)))
 		goto out_unlock;
 
-	cgroup_taskset_for_each(task, css, tset) {
+	cgroup_taskset_for_each(task, tset) {
 		/*
 		 * Kthreads which disallow setaffinity shouldn't be moved
 		 * to a new cpuset; we don't want to change their cpu
@@ -1516,10 +1451,8 @@ static void cpuset_attach(struct cgroup_subsys_state *css,
 	struct mm_struct *mm;
 	struct task_struct *task;
 	struct task_struct *leader = cgroup_taskset_first(tset);
-	struct cgroup_subsys_state *oldcss = cgroup_taskset_cur_css(tset,
-							cpuset_subsys_id);
 	struct cpuset *cs = css_cs(css);
-	struct cpuset *oldcs = css_cs(oldcss);
+	struct cpuset *oldcs = cpuset_attach_old_cs;
 	struct cpuset *cpus_cs = effective_cpumask_cpuset(cs);
 	struct cpuset *mems_cs = effective_nodemask_cpuset(cs);
 
@@ -1533,7 +1466,7 @@ static void cpuset_attach(struct cgroup_subsys_state *css,
 
 	guarantee_online_mems(mems_cs, &cpuset_attach_nodemask_to);
 
-	cgroup_taskset_for_each(task, css, tset) {
+	cgroup_taskset_for_each(task, tset) {
 		/*
 		 * can_attach beforehand should guarantee that this doesn't
 		 * fail.  TODO: have a better way to handle failure here
@@ -1673,7 +1606,7 @@ out_unlock:
  * Common handling for a write to a "cpus" or "mems" file.
  */
 static int cpuset_write_resmask(struct cgroup_subsys_state *css,
-				struct cftype *cft, const char *buf)
+				struct cftype *cft, char *buf)
 {
 	struct cpuset *cs = css_cs(css);
 	struct cpuset *trialcs;
@@ -2020,8 +1953,7 @@ static void cpuset_css_free(struct cgroup_subsys_state *css)
 	kfree(cs);
 }
 
-struct cgroup_subsys cpuset_subsys = {
-	.name = "cpuset",
+struct cgroup_subsys cpuset_cgrp_subsys = {
 	.css_alloc = cpuset_css_alloc,
 	.css_online = cpuset_css_online,
 	.css_offline = cpuset_css_offline,
@@ -2029,7 +1961,6 @@ struct cgroup_subsys cpuset_subsys = {
 	.can_attach = cpuset_can_attach,
 	.cancel_attach = cpuset_cancel_attach,
 	.attach = cpuset_attach,
-	.subsys_id = cpuset_subsys_id,
 	.base_cftypes = files,
 	.early_init = 1,
 };
@@ -2086,10 +2017,9 @@ static void remove_tasks_in_empty_cpuset(struct cpuset *cs)
 		parent = parent_cs(parent);
 
 	if (cgroup_transfer_tasks(parent->css.cgroup, cs->css.cgroup)) {
-		rcu_read_lock();
-		printk(KERN_ERR "cpuset: failed to transfer tasks out of empty cpuset %s\n",
-		       cgroup_name(cs->css.cgroup));
-		rcu_read_unlock();
+		printk(KERN_ERR "cpuset: failed to transfer tasks out of empty cpuset ");
+		pr_cont_cgroup_name(cs->css.cgroup);
+		pr_cont("\n");
 	}
 }
 
@@ -2137,7 +2067,7 @@ retry:
 	 */
 	if ((sane && cpumask_empty(cs->cpus_allowed)) ||
 	    (!cpumask_empty(&off_cpus) && !cpumask_empty(cs->cpus_allowed)))
-		update_tasks_cpumask(cs, NULL);
+		update_tasks_cpumask(cs);
 
 	mutex_lock(&callback_mutex);
 	nodes_andnot(cs->mems_allowed, cs->mems_allowed, off_mems);
@@ -2151,7 +2081,7 @@ retry:
 	 */
 	if ((sane && nodes_empty(cs->mems_allowed)) ||
 	    (!nodes_empty(off_mems) && !nodes_empty(cs->mems_allowed)))
-		update_tasks_nodemask(cs, NULL);
+		update_tasks_nodemask(cs);
 
 	is_empty = cpumask_empty(cs->cpus_allowed) ||
 		nodes_empty(cs->mems_allowed);
@@ -2213,7 +2143,7 @@ static void cpuset_hotplug_workfn(struct work_struct *work)
 		mutex_lock(&callback_mutex);
 		top_cpuset.mems_allowed = new_mems;
 		mutex_unlock(&callback_mutex);
-		update_tasks_nodemask(&top_cpuset, NULL);
+		update_tasks_nodemask(&top_cpuset);
 	}
 
 	mutex_unlock(&cpuset_mutex);
@@ -2305,10 +2235,10 @@ void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask)
 	struct cpuset *cpus_cs;
 
 	mutex_lock(&callback_mutex);
-	task_lock(tsk);
+	rcu_read_lock();
 	cpus_cs = effective_cpumask_cpuset(task_cs(tsk));
 	guarantee_online_cpus(cpus_cs, pmask);
-	task_unlock(tsk);
+	rcu_read_unlock();
 	mutex_unlock(&callback_mutex);
 }
 
@@ -2361,10 +2291,10 @@ nodemask_t cpuset_mems_allowed(struct task_struct *tsk)
 	nodemask_t mask;
 
 	mutex_lock(&callback_mutex);
-	task_lock(tsk);
+	rcu_read_lock();
 	mems_cs = effective_nodemask_cpuset(task_cs(tsk));
 	guarantee_online_mems(mems_cs, &mask);
-	task_unlock(tsk);
+	rcu_read_unlock();
 	mutex_unlock(&callback_mutex);
 
 	return mask;
@@ -2480,10 +2410,10 @@ int __cpuset_node_allowed_softwall(int node, gfp_t gfp_mask)
 	/* Not hardwall and node outside mems_allowed: scan up cpusets */
 	mutex_lock(&callback_mutex);
 
-	task_lock(current);
+	rcu_read_lock();
 	cs = nearest_hardwall_ancestor(task_cs(current));
 	allowed = node_isset(node, cs->mems_allowed);
-	task_unlock(current);
+	rcu_read_unlock();
 
 	mutex_unlock(&callback_mutex);
 	return allowed;
@@ -2609,27 +2539,27 @@ int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
  * @task: pointer to task_struct of some task.
  *
  * Description: Prints @task's name, cpuset name, and cached copy of its
- * mems_allowed to the kernel log.  Must hold task_lock(task) to allow
- * dereferencing task_cs(task).
+ * mems_allowed to the kernel log.
  */
 void cpuset_print_task_mems_allowed(struct task_struct *tsk)
 {
 	 /* Statically allocated to prevent using excess stack. */
 	static char cpuset_nodelist[CPUSET_NODELIST_LEN];
 	static DEFINE_SPINLOCK(cpuset_buffer_lock);
+	struct cgroup *cgrp;
 
-	struct cgroup *cgrp = task_cs(tsk)->css.cgroup;
-
-	rcu_read_lock();
 	spin_lock(&cpuset_buffer_lock);
+	rcu_read_lock();
 
+	cgrp = task_cs(tsk)->css.cgroup;
 	nodelist_scnprintf(cpuset_nodelist, CPUSET_NODELIST_LEN,
 			   tsk->mems_allowed);
-	printk(KERN_INFO "%s cpuset=%s mems_allowed=%s\n",
-	       tsk->comm, cgroup_name(cgrp), cpuset_nodelist);
+	printk(KERN_INFO "%s cpuset=", tsk->comm);
+	pr_cont_cgroup_name(cgrp);
+	pr_cont(" mems_allowed=%s\n", cpuset_nodelist);
 
-	spin_unlock(&cpuset_buffer_lock);
 	rcu_read_unlock();
+	spin_unlock(&cpuset_buffer_lock);
 }
 
 /*
@@ -2660,9 +2590,9 @@ int cpuset_memory_pressure_enabled __read_mostly;
 
 void __cpuset_memory_pressure_bump(void)
 {
-	task_lock(current);
+	rcu_read_lock();
 	fmeter_markevent(&task_cs(current)->fmeter);
-	task_unlock(current);
+	rcu_read_unlock();
 }
 
 #ifdef CONFIG_PROC_PID_CPUSET
@@ -2679,12 +2609,12 @@ int proc_cpuset_show(struct seq_file *m, void *unused_v)
 {
 	struct pid *pid;
 	struct task_struct *tsk;
-	char *buf;
+	char *buf, *p;
 	struct cgroup_subsys_state *css;
 	int retval;
 
 	retval = -ENOMEM;
-	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	buf = kmalloc(PATH_MAX, GFP_KERNEL);
 	if (!buf)
 		goto out;
 
@@ -2694,14 +2624,16 @@ int proc_cpuset_show(struct seq_file *m, void *unused_v)
 	if (!tsk)
 		goto out_free;
 
+	retval = -ENAMETOOLONG;
 	rcu_read_lock();
-	css = task_css(tsk, cpuset_subsys_id);
-	retval = cgroup_path(css->cgroup, buf, PAGE_SIZE);
+	css = task_css(tsk, cpuset_cgrp_id);
+	p = cgroup_path(css->cgroup, buf, PATH_MAX);
 	rcu_read_unlock();
-	if (retval < 0)
+	if (!p)
 		goto out_put_task;
-	seq_puts(m, buf);
+	seq_puts(m, p);
 	seq_putc(m, '\n');
+	retval = 0;
 out_put_task:
 	put_task_struct(tsk);
 out_free:
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 334b3980ffc1..2956c8da1605 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -49,6 +49,7 @@
 #include <linux/pid.h>
 #include <linux/smp.h>
 #include <linux/mm.h>
+#include <linux/vmacache.h>
 #include <linux/rcupdate.h>
 
 #include <asm/cacheflush.h>
@@ -224,10 +225,17 @@ static void kgdb_flush_swbreak_addr(unsigned long addr)
 	if (!CACHE_FLUSH_IS_SAFE)
 		return;
 
-	if (current->mm && current->mm->mmap_cache) {
-		flush_cache_range(current->mm->mmap_cache,
-				  addr, addr + BREAK_INSTR_SIZE);
+	if (current->mm) {
+		int i;
+
+		for (i = 0; i < VMACACHE_SIZE; i++) {
+			if (!current->vmacache[i])
+				continue;
+			flush_cache_range(current->vmacache[i],
+					  addr, addr + BREAK_INSTR_SIZE);
+		}
 	}
+
 	/* Force flush instruction cache if it was outside the mm */
 	flush_icache_range(addr, addr + BREAK_INSTR_SIZE);
 }
@@ -1035,7 +1043,7 @@ int dbg_io_get_char(void)
  * otherwise as a quick means to stop program execution and "break" into
  * the debugger.
  */
-void kgdb_breakpoint(void)
+noinline void kgdb_breakpoint(void)
 {
 	atomic_inc(&kgdb_setting_breakpoint);
 	wmb(); /* Sync point before breakpoint */
diff --git a/kernel/events/core.c b/kernel/events/core.c
index fa0b2d4ad83c..440eefc67397 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -231,11 +231,29 @@ int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write,
 #define NR_ACCUMULATED_SAMPLES 128
 static DEFINE_PER_CPU(u64, running_sample_length);
 
-void perf_sample_event_took(u64 sample_len_ns)
+static void perf_duration_warn(struct irq_work *w)
 {
+	u64 allowed_ns = ACCESS_ONCE(perf_sample_allowed_ns);
 	u64 avg_local_sample_len;
 	u64 local_samples_len;
+
+	local_samples_len = __get_cpu_var(running_sample_length);
+	avg_local_sample_len = local_samples_len/NR_ACCUMULATED_SAMPLES;
+
+	printk_ratelimited(KERN_WARNING
+			"perf interrupt took too long (%lld > %lld), lowering "
+			"kernel.perf_event_max_sample_rate to %d\n",
+			avg_local_sample_len, allowed_ns >> 1,
+			sysctl_perf_event_sample_rate);
+}
+
+static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn);
+
+void perf_sample_event_took(u64 sample_len_ns)
+{
 	u64 allowed_ns = ACCESS_ONCE(perf_sample_allowed_ns);
+	u64 avg_local_sample_len;
+	u64 local_samples_len;
 
 	if (allowed_ns == 0)
 		return;
@@ -263,13 +281,14 @@ void perf_sample_event_took(u64 sample_len_ns)
 	sysctl_perf_event_sample_rate = max_samples_per_tick * HZ;
 	perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate;
 
-	printk_ratelimited(KERN_WARNING
-			"perf samples too long (%lld > %lld), lowering "
-			"kernel.perf_event_max_sample_rate to %d\n",
-			avg_local_sample_len, allowed_ns,
-			sysctl_perf_event_sample_rate);
-
 	update_perf_cpu_limits();
+
+	if (!irq_work_queue(&perf_duration_work)) {
+		early_printk("perf interrupt took too long (%lld > %lld), lowering "
+			     "kernel.perf_event_max_sample_rate to %d\n",
+			     avg_local_sample_len, allowed_ns >> 1,
+			     sysctl_perf_event_sample_rate);
+	}
 }
 
 static atomic64_t perf_event_id;
@@ -342,7 +361,7 @@ struct perf_cgroup {
 static inline struct perf_cgroup *
 perf_cgroup_from_task(struct task_struct *task)
 {
-	return container_of(task_css(task, perf_subsys_id),
+	return container_of(task_css(task, perf_event_cgrp_id),
 			    struct perf_cgroup, css);
 }
 
@@ -370,11 +389,6 @@ perf_cgroup_match(struct perf_event *event)
 				    event->cgrp->css.cgroup);
 }
 
-static inline bool perf_tryget_cgroup(struct perf_event *event)
-{
-	return css_tryget(&event->cgrp->css);
-}
-
 static inline void perf_put_cgroup(struct perf_event *event)
 {
 	css_put(&event->cgrp->css);
@@ -593,9 +607,7 @@ static inline int perf_cgroup_connect(int fd, struct perf_event *event,
 	if (!f.file)
 		return -EBADF;
 
-	rcu_read_lock();
-
-	css = css_from_dir(f.file->f_dentry, &perf_subsys);
+	css = css_tryget_from_dir(f.file->f_dentry, &perf_event_cgrp_subsys);
 	if (IS_ERR(css)) {
 		ret = PTR_ERR(css);
 		goto out;
@@ -604,13 +616,6 @@ static inline int perf_cgroup_connect(int fd, struct perf_event *event,
 	cgrp = container_of(css, struct perf_cgroup, css);
 	event->cgrp = cgrp;
 
-	/* must be done before we fput() the file */
-	if (!perf_tryget_cgroup(event)) {
-		event->cgrp = NULL;
-		ret = -ENOENT;
-		goto out;
-	}
-
 	/*
 	 * all events in a group must monitor
 	 * the same cgroup because a task belongs
@@ -621,7 +626,6 @@ static inline int perf_cgroup_connect(int fd, struct perf_event *event,
 		ret = -EINVAL;
 	}
 out:
-	rcu_read_unlock();
 	fdput(f);
 	return ret;
 }
@@ -1439,6 +1443,11 @@ group_sched_out(struct perf_event *group_event,
 		cpuctx->exclusive = 0;
 }
 
+struct remove_event {
+	struct perf_event *event;
+	bool detach_group;
+};
+
 /*
  * Cross CPU call to remove a performance event
  *
@@ -1447,12 +1456,15 @@ group_sched_out(struct perf_event *group_event,
  */
 static int __perf_remove_from_context(void *info)
 {
-	struct perf_event *event = info;
+	struct remove_event *re = info;
+	struct perf_event *event = re->event;
 	struct perf_event_context *ctx = event->ctx;
 	struct perf_cpu_context *cpuctx = __get_cpu_context(ctx);
 
 	raw_spin_lock(&ctx->lock);
 	event_sched_out(event, cpuctx, ctx);
+	if (re->detach_group)
+		perf_group_detach(event);
 	list_del_event(event, ctx);
 	if (!ctx->nr_events && cpuctx->task_ctx == ctx) {
 		ctx->is_active = 0;
@@ -1477,10 +1489,14 @@ static int __perf_remove_from_context(void *info)
  * When called from perf_event_exit_task, it's OK because the
  * context has been detached from its task.
  */
-static void perf_remove_from_context(struct perf_event *event)
+static void perf_remove_from_context(struct perf_event *event, bool detach_group)
 {
 	struct perf_event_context *ctx = event->ctx;
 	struct task_struct *task = ctx->task;
+	struct remove_event re = {
+		.event = event,
+		.detach_group = detach_group,
+	};
 
 	lockdep_assert_held(&ctx->mutex);
 
@@ -1489,12 +1505,12 @@ static void perf_remove_from_context(struct perf_event *event)
 		 * Per cpu events are removed via an smp call and
 		 * the removal is always successful.
 		 */
-		cpu_function_call(event->cpu, __perf_remove_from_context, event);
+		cpu_function_call(event->cpu, __perf_remove_from_context, &re);
 		return;
 	}
 
 retry:
-	if (!task_function_call(task, __perf_remove_from_context, event))
+	if (!task_function_call(task, __perf_remove_from_context, &re))
 		return;
 
 	raw_spin_lock_irq(&ctx->lock);
@@ -1511,6 +1527,8 @@ retry:
 	 * Since the task isn't running, its safe to remove the event, us
 	 * holding the ctx->lock ensures the task won't get scheduled in.
 	 */
+	if (detach_group)
+		perf_group_detach(event);
 	list_del_event(event, ctx);
 	raw_spin_unlock_irq(&ctx->lock);
 }
@@ -1714,7 +1732,7 @@ group_sched_in(struct perf_event *group_event,
 	       struct perf_event_context *ctx)
 {
 	struct perf_event *event, *partial_group = NULL;
-	struct pmu *pmu = group_event->pmu;
+	struct pmu *pmu = ctx->pmu;
 	u64 now = ctx->time;
 	bool simulate = false;
 
@@ -2563,8 +2581,6 @@ static void perf_branch_stack_sched_in(struct task_struct *prev,
 		if (cpuctx->ctx.nr_branch_stack > 0
 		    && pmu->flush_branch_stack) {
 
-			pmu = cpuctx->ctx.pmu;
-
 			perf_ctx_lock(cpuctx, cpuctx->task_ctx);
 
 			perf_pmu_disable(pmu);
@@ -3176,7 +3192,8 @@ static void free_event_rcu(struct rcu_head *head)
 }
 
 static void ring_buffer_put(struct ring_buffer *rb);
-static void ring_buffer_detach(struct perf_event *event, struct ring_buffer *rb);
+static void ring_buffer_attach(struct perf_event *event,
+			       struct ring_buffer *rb);
 
 static void unaccount_event_cpu(struct perf_event *event, int cpu)
 {
@@ -3236,8 +3253,6 @@ static void free_event(struct perf_event *event)
 	unaccount_event(event);
 
 	if (event->rb) {
-		struct ring_buffer *rb;
-
 		/*
 		 * Can happen when we close an event with re-directed output.
 		 *
@@ -3245,12 +3260,7 @@ static void free_event(struct perf_event *event)
 		 * over us; possibly making our ring_buffer_put() the last.
 		 */
 		mutex_lock(&event->mmap_mutex);
-		rb = event->rb;
-		if (rb) {
-			rcu_assign_pointer(event->rb, NULL);
-			ring_buffer_detach(event, rb);
-			ring_buffer_put(rb); /* could be last */
-		}
+		ring_buffer_attach(event, NULL);
 		mutex_unlock(&event->mmap_mutex);
 	}
 
@@ -3279,10 +3289,7 @@ int perf_event_release_kernel(struct perf_event *event)
 	 *     to trigger the AB-BA case.
 	 */
 	mutex_lock_nested(&ctx->mutex, SINGLE_DEPTH_NESTING);
-	raw_spin_lock_irq(&ctx->lock);
-	perf_group_detach(event);
-	raw_spin_unlock_irq(&ctx->lock);
-	perf_remove_from_context(event);
+	perf_remove_from_context(event, true);
 	mutex_unlock(&ctx->mutex);
 
 	free_event(event);
@@ -3837,28 +3844,47 @@ unlock:
 static void ring_buffer_attach(struct perf_event *event,
 			       struct ring_buffer *rb)
 {
+	struct ring_buffer *old_rb = NULL;
 	unsigned long flags;
 
-	if (!list_empty(&event->rb_entry))
-		return;
+	if (event->rb) {
+		/*
+		 * Should be impossible, we set this when removing
+		 * event->rb_entry and wait/clear when adding event->rb_entry.
+		 */
+		WARN_ON_ONCE(event->rcu_pending);
 
-	spin_lock_irqsave(&rb->event_lock, flags);
-	if (list_empty(&event->rb_entry))
-		list_add(&event->rb_entry, &rb->event_list);
-	spin_unlock_irqrestore(&rb->event_lock, flags);
-}
+		old_rb = event->rb;
+		event->rcu_batches = get_state_synchronize_rcu();
+		event->rcu_pending = 1;
 
-static void ring_buffer_detach(struct perf_event *event, struct ring_buffer *rb)
-{
-	unsigned long flags;
+		spin_lock_irqsave(&old_rb->event_lock, flags);
+		list_del_rcu(&event->rb_entry);
+		spin_unlock_irqrestore(&old_rb->event_lock, flags);
+	}
 
-	if (list_empty(&event->rb_entry))
-		return;
+	if (event->rcu_pending && rb) {
+		cond_synchronize_rcu(event->rcu_batches);
+		event->rcu_pending = 0;
+	}
 
-	spin_lock_irqsave(&rb->event_lock, flags);
-	list_del_init(&event->rb_entry);
-	wake_up_all(&event->waitq);
-	spin_unlock_irqrestore(&rb->event_lock, flags);
+	if (rb) {
+		spin_lock_irqsave(&rb->event_lock, flags);
+		list_add_rcu(&event->rb_entry, &rb->event_list);
+		spin_unlock_irqrestore(&rb->event_lock, flags);
+	}
+
+	rcu_assign_pointer(event->rb, rb);
+
+	if (old_rb) {
+		ring_buffer_put(old_rb);
+		/*
+		 * Since we detached before setting the new rb, so that we
+		 * could attach the new rb, we could have missed a wakeup.
+		 * Provide it now.
+		 */
+		wake_up_all(&event->waitq);
+	}
 }
 
 static void ring_buffer_wakeup(struct perf_event *event)
@@ -3927,7 +3953,7 @@ static void perf_mmap_close(struct vm_area_struct *vma)
 {
 	struct perf_event *event = vma->vm_file->private_data;
 
-	struct ring_buffer *rb = event->rb;
+	struct ring_buffer *rb = ring_buffer_get(event);
 	struct user_struct *mmap_user = rb->mmap_user;
 	int mmap_locked = rb->mmap_locked;
 	unsigned long size = perf_data_size(rb);
@@ -3935,18 +3961,14 @@ static void perf_mmap_close(struct vm_area_struct *vma)
 	atomic_dec(&rb->mmap_count);
 
 	if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex))
-		return;
+		goto out_put;
 
-	/* Detach current event from the buffer. */
-	rcu_assign_pointer(event->rb, NULL);
-	ring_buffer_detach(event, rb);
+	ring_buffer_attach(event, NULL);
 	mutex_unlock(&event->mmap_mutex);
 
 	/* If there's still other mmap()s of this buffer, we're done. */
-	if (atomic_read(&rb->mmap_count)) {
-		ring_buffer_put(rb); /* can't be last */
-		return;
-	}
+	if (atomic_read(&rb->mmap_count))
+		goto out_put;
 
 	/*
 	 * No other mmap()s, detach from all other events that might redirect
@@ -3976,11 +3998,9 @@ again:
 		 * still restart the iteration to make sure we're not now
 		 * iterating the wrong list.
 		 */
-		if (event->rb == rb) {
-			rcu_assign_pointer(event->rb, NULL);
-			ring_buffer_detach(event, rb);
-			ring_buffer_put(rb); /* can't be last, we still have one */
-		}
+		if (event->rb == rb)
+			ring_buffer_attach(event, NULL);
+
 		mutex_unlock(&event->mmap_mutex);
 		put_event(event);
 
@@ -4005,6 +4025,7 @@ again:
 	vma->vm_mm->pinned_vm -= mmap_locked;
 	free_uid(mmap_user);
 
+out_put:
 	ring_buffer_put(rb); /* could be last */
 }
 
@@ -4122,7 +4143,6 @@ again:
 	vma->vm_mm->pinned_vm += extra;
 
 	ring_buffer_attach(event, rb);
-	rcu_assign_pointer(event->rb, rb);
 
 	perf_event_init_userpage(event);
 	perf_event_update_userpage(event);
@@ -5406,6 +5426,9 @@ struct swevent_htable {
 
 	/* Recursion avoidance in each contexts */
 	int				recursion[PERF_NR_CONTEXTS];
+
+	/* Keeps track of cpu being initialized/exited */
+	bool				online;
 };
 
 static DEFINE_PER_CPU(struct swevent_htable, swevent_htable);
@@ -5652,8 +5675,14 @@ static int perf_swevent_add(struct perf_event *event, int flags)
 	hwc->state = !(flags & PERF_EF_START);
 
 	head = find_swevent_head(swhash, event);
-	if (WARN_ON_ONCE(!head))
+	if (!head) {
+		/*
+		 * We can race with cpu hotplug code. Do not
+		 * WARN if the cpu just got unplugged.
+		 */
+		WARN_ON_ONCE(swhash->online);
 		return -EINVAL;
+	}
 
 	hlist_add_head_rcu(&event->hlist_entry, head);
 
@@ -6294,7 +6323,7 @@ static int perf_event_idx_default(struct perf_event *event)
  * Ensures all contexts with the same task_ctx_nr have the same
  * pmu_cpu_context too.
  */
-static void *find_pmu_context(int ctxn)
+static struct perf_cpu_context __percpu *find_pmu_context(int ctxn)
 {
 	struct pmu *pmu;
 
@@ -6912,7 +6941,7 @@ err_size:
 static int
 perf_event_set_output(struct perf_event *event, struct perf_event *output_event)
 {
-	struct ring_buffer *rb = NULL, *old_rb = NULL;
+	struct ring_buffer *rb = NULL;
 	int ret = -EINVAL;
 
 	if (!output_event)
@@ -6940,8 +6969,6 @@ set:
 	if (atomic_read(&event->mmap_count))
 		goto unlock;
 
-	old_rb = event->rb;
-
 	if (output_event) {
 		/* get the rb we want to redirect to */
 		rb = ring_buffer_get(output_event);
@@ -6949,23 +6976,7 @@ set:
 			goto unlock;
 	}
 
-	if (old_rb)
-		ring_buffer_detach(event, old_rb);
-
-	if (rb)
-		ring_buffer_attach(event, rb);
-
-	rcu_assign_pointer(event->rb, rb);
-
-	if (old_rb) {
-		ring_buffer_put(old_rb);
-		/*
-		 * Since we detached before setting the new rb, so that we
-		 * could attach the new rb, we could have missed a wakeup.
-		 * Provide it now.
-		 */
-		wake_up_all(&event->waitq);
-	}
+	ring_buffer_attach(event, rb);
 
 	ret = 0;
 unlock:
@@ -7016,6 +7027,9 @@ SYSCALL_DEFINE5(perf_event_open,
 	if (attr.freq) {
 		if (attr.sample_freq > sysctl_perf_event_sample_rate)
 			return -EINVAL;
+	} else {
+		if (attr.sample_period & (1ULL << 63))
+			return -EINVAL;
 	}
 
 	/*
@@ -7163,7 +7177,7 @@ SYSCALL_DEFINE5(perf_event_open,
 		struct perf_event_context *gctx = group_leader->ctx;
 
 		mutex_lock(&gctx->mutex);
-		perf_remove_from_context(group_leader);
+		perf_remove_from_context(group_leader, false);
 
 		/*
 		 * Removing from the context ends up with disabled
@@ -7173,7 +7187,7 @@ SYSCALL_DEFINE5(perf_event_open,
 		perf_event__state_init(group_leader);
 		list_for_each_entry(sibling, &group_leader->sibling_list,
 				    group_entry) {
-			perf_remove_from_context(sibling);
+			perf_remove_from_context(sibling, false);
 			perf_event__state_init(sibling);
 			put_ctx(gctx);
 		}
@@ -7303,7 +7317,7 @@ void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu)
 	mutex_lock(&src_ctx->mutex);
 	list_for_each_entry_safe(event, tmp, &src_ctx->event_list,
 				 event_entry) {
-		perf_remove_from_context(event);
+		perf_remove_from_context(event, false);
 		unaccount_event_cpu(event, src_cpu);
 		put_ctx(src_ctx);
 		list_add(&event->migrate_entry, &events);
@@ -7365,13 +7379,7 @@ __perf_event_exit_task(struct perf_event *child_event,
 			 struct perf_event_context *child_ctx,
 			 struct task_struct *child)
 {
-	if (child_event->parent) {
-		raw_spin_lock_irq(&child_ctx->lock);
-		perf_group_detach(child_event);
-		raw_spin_unlock_irq(&child_ctx->lock);
-	}
-
-	perf_remove_from_context(child_event);
+	perf_remove_from_context(child_event, !!child_event->parent);
 
 	/*
 	 * It can happen that the parent exits first, and has events
@@ -7722,6 +7730,8 @@ int perf_event_init_context(struct task_struct *child, int ctxn)
 	 * swapped under us.
 	 */
 	parent_ctx = perf_pin_task_context(parent, ctxn);
+	if (!parent_ctx)
+		return 0;
 
 	/*
 	 * No need to check if parent_ctx != NULL here; since we saw
@@ -7833,6 +7843,7 @@ static void perf_event_init_cpu(int cpu)
 	struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu);
 
 	mutex_lock(&swhash->hlist_mutex);
+	swhash->online = true;
 	if (swhash->hlist_refcount > 0) {
 		struct swevent_hlist *hlist;
 
@@ -7855,14 +7866,14 @@ static void perf_pmu_rotate_stop(struct pmu *pmu)
 
 static void __perf_event_exit_context(void *__info)
 {
+	struct remove_event re = { .detach_group = false };
 	struct perf_event_context *ctx = __info;
-	struct perf_event *event;
 
 	perf_pmu_rotate_stop(ctx->pmu);
 
 	rcu_read_lock();
-	list_for_each_entry_rcu(event, &ctx->event_list, event_entry)
-		__perf_remove_from_context(event);
+	list_for_each_entry_rcu(re.event, &ctx->event_list, event_entry)
+		__perf_remove_from_context(&re);
 	rcu_read_unlock();
 }
 
@@ -7890,6 +7901,7 @@ static void perf_event_exit_cpu(int cpu)
 	perf_event_exit_cpu_context(cpu);
 
 	mutex_lock(&swhash->hlist_mutex);
+	swhash->online = false;
 	swevent_hlist_release(swhash);
 	mutex_unlock(&swhash->hlist_mutex);
 }
@@ -8036,7 +8048,7 @@ static void perf_cgroup_attach(struct cgroup_subsys_state *css,
 {
 	struct task_struct *task;
 
-	cgroup_taskset_for_each(task, css, tset)
+	cgroup_taskset_for_each(task, tset)
 		task_function_call(task, __perf_cgroup_move, task);
 }
 
@@ -8055,9 +8067,7 @@ static void perf_cgroup_exit(struct cgroup_subsys_state *css,
 	task_function_call(task, __perf_cgroup_move, task);
 }
 
-struct cgroup_subsys perf_subsys = {
-	.name		= "perf_event",
-	.subsys_id	= perf_subsys_id,
+struct cgroup_subsys perf_event_cgrp_subsys = {
 	.css_alloc	= perf_cgroup_css_alloc,
 	.css_free	= perf_cgroup_css_free,
 	.exit		= perf_cgroup_exit,
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 307d87c0991a..04709b66369d 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1804,6 +1804,11 @@ static bool handle_trampoline(struct pt_regs *regs)
 	return true;
 }
 
+bool __weak arch_uprobe_ignore(struct arch_uprobe *aup, struct pt_regs *regs)
+{
+	return false;
+}
+
 /*
  * Run handler and ask thread to singlestep.
  * Ensure all non-fatal signals cannot interrupt thread while it singlesteps.
@@ -1858,7 +1863,11 @@ static void handle_swbp(struct pt_regs *regs)
 	if (!get_utask())
 		goto out;
 
+	if (arch_uprobe_ignore(&uprobe->arch, regs))
+		goto out;
+
 	handler_chain(uprobe, regs);
+
 	if (can_skip_sstep(uprobe, regs))
 		goto out;
 
diff --git a/kernel/exit.c b/kernel/exit.c
index 1e77fc645317..6ed6a1d552b5 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -570,7 +570,7 @@ static void reparent_leader(struct task_struct *father, struct task_struct *p,
 	if (same_thread_group(p->real_parent, father))
 		return;
 
-	/* We don't want people slaying init.  */
+	/* We don't want people slaying init. */
 	p->exit_signal = SIGCHLD;
 
 	/* If it has exited notify the new parent about this child's death. */
@@ -784,9 +784,10 @@ void do_exit(long code)
 	exit_shm(tsk);
 	exit_files(tsk);
 	exit_fs(tsk);
+	if (group_dead)
+		disassociate_ctty(1);
 	exit_task_namespaces(tsk);
 	exit_task_work(tsk);
-	check_stack_usage();
 	exit_thread();
 
 	/*
@@ -797,21 +798,17 @@ void do_exit(long code)
 	 */
 	perf_event_exit_task(tsk);
 
-	cgroup_exit(tsk, 1);
-
-	if (group_dead)
-		disassociate_ctty(1);
+	cgroup_exit(tsk);
 
 	module_put(task_thread_info(tsk)->exec_domain->module);
 
-	proc_exit_connector(tsk);
-
 	/*
 	 * FIXME: do that only when needed, using sched_exit tracepoint
 	 */
 	flush_ptrace_hw_breakpoint(tsk);
 
 	exit_notify(tsk, group_dead);
+	proc_exit_connector(tsk);
 #ifdef CONFIG_NUMA
 	task_lock(tsk);
 	mpol_put(tsk->mempolicy);
@@ -844,6 +841,7 @@ void do_exit(long code)
 
 	validate_creds_for_do_exit(tsk);
 
+	check_stack_usage();
 	preempt_disable();
 	if (tsk->nr_dirtied)
 		__this_cpu_add(dirty_throttle_leaks, tsk->nr_dirtied);
@@ -1038,17 +1036,13 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
 		return wait_noreap_copyout(wo, p, pid, uid, why, status);
 	}
 
+	traced = ptrace_reparented(p);
 	/*
-	 * Try to move the task's state to DEAD
-	 * only one thread is allowed to do this:
+	 * Move the task's state to DEAD/TRACE, only one thread can do this.
 	 */
-	state = xchg(&p->exit_state, EXIT_DEAD);
-	if (state != EXIT_ZOMBIE) {
-		BUG_ON(state != EXIT_DEAD);
+	state = traced && thread_group_leader(p) ? EXIT_TRACE : EXIT_DEAD;
+	if (cmpxchg(&p->exit_state, EXIT_ZOMBIE, state) != EXIT_ZOMBIE)
 		return 0;
-	}
-
-	traced = ptrace_reparented(p);
 	/*
 	 * It can be ptraced but not reparented, check
 	 * thread_group_leader() to filter out sub-threads.
@@ -1109,7 +1103,7 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
 
 	/*
 	 * Now we are sure this task is interesting, and no other
-	 * thread can reap it because we set its state to EXIT_DEAD.
+	 * thread can reap it because we its state == DEAD/TRACE.
 	 */
 	read_unlock(&tasklist_lock);
 
@@ -1146,22 +1140,19 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
 	if (!retval)
 		retval = pid;
 
-	if (traced) {
+	if (state == EXIT_TRACE) {
 		write_lock_irq(&tasklist_lock);
 		/* We dropped tasklist, ptracer could die and untrace */
 		ptrace_unlink(p);
-		/*
-		 * If this is not a sub-thread, notify the parent.
-		 * If parent wants a zombie, don't release it now.
-		 */
-		if (thread_group_leader(p) &&
-		    !do_notify_parent(p, p->exit_signal)) {
-			p->exit_state = EXIT_ZOMBIE;
-			p = NULL;
-		}
+
+		/* If parent wants a zombie, don't release it now */
+		state = EXIT_ZOMBIE;
+		if (do_notify_parent(p, p->exit_signal))
+			state = EXIT_DEAD;
+		p->exit_state = state;
 		write_unlock_irq(&tasklist_lock);
 	}
-	if (p != NULL)
+	if (state == EXIT_DEAD)
 		release_task(p);
 
 	return retval;
@@ -1338,7 +1329,12 @@ static int wait_task_continued(struct wait_opts *wo, struct task_struct *p)
 static int wait_consider_task(struct wait_opts *wo, int ptrace,
 				struct task_struct *p)
 {
-	int ret = eligible_child(wo, p);
+	int ret;
+
+	if (unlikely(p->exit_state == EXIT_DEAD))
+		return 0;
+
+	ret = eligible_child(wo, p);
 	if (!ret)
 		return ret;
 
@@ -1356,33 +1352,44 @@ static int wait_consider_task(struct wait_opts *wo, int ptrace,
 		return 0;
 	}
 
-	/* dead body doesn't have much to contribute */
-	if (unlikely(p->exit_state == EXIT_DEAD)) {
+	if (unlikely(p->exit_state == EXIT_TRACE)) {
 		/*
-		 * But do not ignore this task until the tracer does
-		 * wait_task_zombie()->do_notify_parent().
+		 * ptrace == 0 means we are the natural parent. In this case
+		 * we should clear notask_error, debugger will notify us.
 		 */
-		if (likely(!ptrace) && unlikely(ptrace_reparented(p)))
+		if (likely(!ptrace))
 			wo->notask_error = 0;
 		return 0;
 	}
 
-	/* slay zombie? */
-	if (p->exit_state == EXIT_ZOMBIE) {
+	if (likely(!ptrace) && unlikely(p->ptrace)) {
 		/*
-		 * A zombie ptracee is only visible to its ptracer.
-		 * Notification and reaping will be cascaded to the real
-		 * parent when the ptracer detaches.
+		 * If it is traced by its real parent's group, just pretend
+		 * the caller is ptrace_do_wait() and reap this child if it
+		 * is zombie.
+		 *
+		 * This also hides group stop state from real parent; otherwise
+		 * a single stop can be reported twice as group and ptrace stop.
+		 * If a ptracer wants to distinguish these two events for its
+		 * own children it should create a separate process which takes
+		 * the role of real parent.
 		 */
-		if (likely(!ptrace) && unlikely(p->ptrace)) {
-			/* it will become visible, clear notask_error */
-			wo->notask_error = 0;
-			return 0;
-		}
+		if (!ptrace_reparented(p))
+			ptrace = 1;
+	}
 
+	/* slay zombie? */
+	if (p->exit_state == EXIT_ZOMBIE) {
 		/* we don't reap group leaders with subthreads */
-		if (!delay_group_leader(p))
-			return wait_task_zombie(wo, p);
+		if (!delay_group_leader(p)) {
+			/*
+			 * A zombie ptracee is only visible to its ptracer.
+			 * Notification and reaping will be cascaded to the
+			 * real parent when the ptracer detaches.
+			 */
+			if (unlikely(ptrace) || likely(!p->ptrace))
+				return wait_task_zombie(wo, p);
+		}
 
 		/*
 		 * Allow access to stopped/continued state via zombie by
@@ -1408,19 +1415,6 @@ static int wait_consider_task(struct wait_opts *wo, int ptrace,
 			wo->notask_error = 0;
 	} else {
 		/*
-		 * If @p is ptraced by a task in its real parent's group,
-		 * hide group stop/continued state when looking at @p as
-		 * the real parent; otherwise, a single stop can be
-		 * reported twice as group and ptrace stops.
-		 *
-		 * If a ptracer wants to distinguish the two events for its
-		 * own children, it should create a separate process which
-		 * takes the role of real parent.
-		 */
-		if (likely(!ptrace) && p->ptrace && !ptrace_reparented(p))
-			return 0;
-
-		/*
 		 * @p is alive and it's gonna stop, continue or exit, so
 		 * there always is something to wait for.
 		 */
diff --git a/kernel/extable.c b/kernel/extable.c
index 763faf037ec1..d8a6446adbcb 100644
--- a/kernel/extable.c
+++ b/kernel/extable.c
@@ -36,7 +36,7 @@ extern struct exception_table_entry __start___ex_table[];
 extern struct exception_table_entry __stop___ex_table[];
 
 /* Cleared by build time tools if the table is already sorted. */
-u32 __initdata main_extable_sort_needed = 1;
+u32 __initdata __visible main_extable_sort_needed = 1;
 
 /* Sort the kernel's built-in exception table */
 void __init sort_main_extable(void)
diff --git a/kernel/fork.c b/kernel/fork.c
index a17621c6cd42..54a8d26f612f 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -28,6 +28,8 @@
 #include <linux/mman.h>
 #include <linux/mmu_notifier.h>
 #include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/vmacache.h>
 #include <linux/nsproxy.h>
 #include <linux/capability.h>
 #include <linux/cpu.h>
@@ -71,6 +73,7 @@
 #include <linux/signalfd.h>
 #include <linux/uprobes.h>
 #include <linux/aio.h>
+#include <linux/compiler.h>
 
 #include <asm/pgtable.h>
 #include <asm/pgalloc.h>
@@ -237,6 +240,7 @@ void __put_task_struct(struct task_struct *tsk)
 	WARN_ON(atomic_read(&tsk->usage));
 	WARN_ON(tsk == current);
 
+	task_numa_free(tsk);
 	security_task_free(tsk);
 	exit_creds(tsk);
 	delayacct_tsk_free(tsk);
@@ -283,7 +287,7 @@ void __init fork_init(unsigned long mempages)
 		init_task.signal->rlim[RLIMIT_NPROC];
 }
 
-int __attribute__((weak)) arch_dup_task_struct(struct task_struct *dst,
+int __weak arch_dup_task_struct(struct task_struct *dst,
 					       struct task_struct *src)
 {
 	*dst = *src;
@@ -363,7 +367,7 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
 
 	mm->locked_vm = 0;
 	mm->mmap = NULL;
-	mm->mmap_cache = NULL;
+	mm->vmacache_seqnum = 0;
 	mm->map_count = 0;
 	cpumask_clear(mm_cpumask(mm));
 	mm->mm_rb = RB_ROOT;
@@ -529,8 +533,6 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p)
 	atomic_set(&mm->mm_count, 1);
 	init_rwsem(&mm->mmap_sem);
 	INIT_LIST_HEAD(&mm->mmlist);
-	mm->flags = (current->mm) ?
-		(current->mm->flags & MMF_INIT_MASK) : default_dump_filter;
 	mm->core_state = NULL;
 	atomic_long_set(&mm->nr_ptes, 0);
 	memset(&mm->rss_stat, 0, sizeof(mm->rss_stat));
@@ -539,8 +541,15 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p)
 	mm_init_owner(mm, p);
 	clear_tlb_flush_pending(mm);
 
-	if (likely(!mm_alloc_pgd(mm))) {
+	if (current->mm) {
+		mm->flags = current->mm->flags & MMF_INIT_MASK;
+		mm->def_flags = current->mm->def_flags & VM_INIT_DEF_MASK;
+	} else {
+		mm->flags = default_dump_filter;
 		mm->def_flags = 0;
+	}
+
+	if (likely(!mm_alloc_pgd(mm))) {
 		mmu_notifier_mm_init(mm);
 		return mm;
 	}
@@ -876,6 +885,9 @@ static int copy_mm(unsigned long clone_flags, struct task_struct *tsk)
 	if (!oldmm)
 		return 0;
 
+	/* initialize the new vmacache entries */
+	vmacache_flush(tsk);
+
 	if (clone_flags & CLONE_VM) {
 		atomic_inc(&oldmm->mm_users);
 		mm = oldmm;
@@ -1069,15 +1081,6 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
 	return 0;
 }
 
-static void copy_flags(unsigned long clone_flags, struct task_struct *p)
-{
-	unsigned long new_flags = p->flags;
-
-	new_flags &= ~(PF_SUPERPRIV | PF_WQ_WORKER);
-	new_flags |= PF_FORKNOEXEC;
-	p->flags = new_flags;
-}
-
 SYSCALL_DEFINE1(set_tid_address, int __user *, tidptr)
 {
 	current->clear_child_tid = tidptr;
@@ -1227,7 +1230,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 		goto bad_fork_cleanup_count;
 
 	delayacct_tsk_init(p);	/* Must remain after dup_task_struct() */
-	copy_flags(clone_flags, p);
+	p->flags &= ~(PF_SUPERPRIV | PF_WQ_WORKER);
+	p->flags |= PF_FORKNOEXEC;
 	INIT_LIST_HEAD(&p->children);
 	INIT_LIST_HEAD(&p->sibling);
 	rcu_copy_process(p);
@@ -1271,9 +1275,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 	if (IS_ERR(p->mempolicy)) {
 		retval = PTR_ERR(p->mempolicy);
 		p->mempolicy = NULL;
-		goto bad_fork_cleanup_cgroup;
+		goto bad_fork_cleanup_threadgroup_lock;
 	}
-	mpol_fix_fork_child_flag(p);
 #endif
 #ifdef CONFIG_CPUSETS
 	p->cpuset_mem_spread_rotor = NUMA_NO_NODE;
@@ -1524,11 +1527,10 @@ bad_fork_cleanup_policy:
 	perf_event_free_task(p);
 #ifdef CONFIG_NUMA
 	mpol_put(p->mempolicy);
-bad_fork_cleanup_cgroup:
+bad_fork_cleanup_threadgroup_lock:
 #endif
 	if (clone_flags & CLONE_THREAD)
 		threadgroup_change_end(current);
-	cgroup_exit(p, 0);
 	delayacct_tsk_free(p);
 	module_put(task_thread_info(p)->exec_domain->module);
 bad_fork_cleanup_count:
diff --git a/kernel/futex.c b/kernel/futex.c
index 08ec814ad9d2..de938d20df19 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -70,7 +70,10 @@
 #include "locking/rtmutex_common.h"
 
 /*
- * Basic futex operation and ordering guarantees:
+ * READ this before attempting to hack on futexes!
+ *
+ * Basic futex operation and ordering guarantees
+ * =============================================
  *
  * The waiter reads the futex value in user space and calls
  * futex_wait(). This function computes the hash bucket and acquires
@@ -119,7 +122,7 @@
  * sys_futex(WAIT, futex, val);
  *   futex_wait(futex, val);
  *
- *   waiters++;
+ *   waiters++; (a)
  *   mb(); (A) <-- paired with -.
  *                              |
  *   lock(hash_bucket(futex));  |
@@ -135,14 +138,14 @@
  *     unlock(hash_bucket(futex));
  *     schedule();                         if (waiters)
  *                                           lock(hash_bucket(futex));
- *                                           wake_waiters(futex);
- *                                           unlock(hash_bucket(futex));
+ *   else                                    wake_waiters(futex);
+ *     waiters--; (b)                        unlock(hash_bucket(futex));
  *
- * Where (A) orders the waiters increment and the futex value read -- this
- * is guaranteed by the head counter in the hb spinlock; and where (B)
- * orders the write to futex and the waiters read -- this is done by the
- * barriers in get_futex_key_refs(), through either ihold or atomic_inc,
- * depending on the futex type.
+ * Where (A) orders the waiters increment and the futex value read through
+ * atomic operations (see hb_waiters_inc) and where (B) orders the write
+ * to futex and the waiters read -- this is done by the barriers in
+ * get_futex_key_refs(), through either ihold or atomic_inc, depending on the
+ * futex type.
  *
  * This yields the following case (where X:=waiters, Y:=futex):
  *
@@ -155,9 +158,22 @@
  * Which guarantees that x==0 && y==0 is impossible; which translates back into
  * the guarantee that we cannot both miss the futex variable change and the
  * enqueue.
+ *
+ * Note that a new waiter is accounted for in (a) even when it is possible that
+ * the wait call can return error, in which case we backtrack from it in (b).
+ * Refer to the comment in queue_lock().
+ *
+ * Similarly, in order to account for waiters being requeued on another
+ * address we always increment the waiters for the destination bucket before
+ * acquiring the lock. It then decrements them again  after releasing it -
+ * the code that actually moves the futex(es) between hash buckets (requeue_futex)
+ * will do the additional required waiter count housekeeping. This is done for
+ * double_lock_hb() and double_unlock_hb(), respectively.
  */
 
+#ifndef CONFIG_HAVE_FUTEX_CMPXCHG
 int __read_mostly futex_cmpxchg_enabled;
+#endif
 
 /*
  * Futex flags used to encode options to functions and preserve them across
@@ -727,6 +743,55 @@ void exit_pi_state_list(struct task_struct *curr)
 	raw_spin_unlock_irq(&curr->pi_lock);
 }
 
+/*
+ * We need to check the following states:
+ *
+ *      Waiter | pi_state | pi->owner | uTID      | uODIED | ?
+ *
+ * [1]  NULL   | ---      | ---       | 0         | 0/1    | Valid
+ * [2]  NULL   | ---      | ---       | >0        | 0/1    | Valid
+ *
+ * [3]  Found  | NULL     | --        | Any       | 0/1    | Invalid
+ *
+ * [4]  Found  | Found    | NULL      | 0         | 1      | Valid
+ * [5]  Found  | Found    | NULL      | >0        | 1      | Invalid
+ *
+ * [6]  Found  | Found    | task      | 0         | 1      | Valid
+ *
+ * [7]  Found  | Found    | NULL      | Any       | 0      | Invalid
+ *
+ * [8]  Found  | Found    | task      | ==taskTID | 0/1    | Valid
+ * [9]  Found  | Found    | task      | 0         | 0      | Invalid
+ * [10] Found  | Found    | task      | !=taskTID | 0/1    | Invalid
+ *
+ * [1]	Indicates that the kernel can acquire the futex atomically. We
+ *	came came here due to a stale FUTEX_WAITERS/FUTEX_OWNER_DIED bit.
+ *
+ * [2]	Valid, if TID does not belong to a kernel thread. If no matching
+ *      thread is found then it indicates that the owner TID has died.
+ *
+ * [3]	Invalid. The waiter is queued on a non PI futex
+ *
+ * [4]	Valid state after exit_robust_list(), which sets the user space
+ *	value to FUTEX_WAITERS | FUTEX_OWNER_DIED.
+ *
+ * [5]	The user space value got manipulated between exit_robust_list()
+ *	and exit_pi_state_list()
+ *
+ * [6]	Valid state after exit_pi_state_list() which sets the new owner in
+ *	the pi_state but cannot access the user space value.
+ *
+ * [7]	pi_state->owner can only be NULL when the OWNER_DIED bit is set.
+ *
+ * [8]	Owner and user space value match
+ *
+ * [9]	There is no transient state which sets the user space TID to 0
+ *	except exit_robust_list(), but this is indicated by the
+ *	FUTEX_OWNER_DIED bit. See [4]
+ *
+ * [10] There is no transient state which leaves owner and user space
+ *	TID out of sync.
+ */
 static int
 lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
 		union futex_key *key, struct futex_pi_state **ps)
@@ -739,12 +804,13 @@ lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
 	plist_for_each_entry_safe(this, next, &hb->chain, list) {
 		if (match_futex(&this->key, key)) {
 			/*
-			 * Another waiter already exists - bump up
-			 * the refcount and return its pi_state:
+			 * Sanity check the waiter before increasing
+			 * the refcount and attaching to it.
 			 */
 			pi_state = this->pi_state;
 			/*
-			 * Userspace might have messed up non-PI and PI futexes
+			 * Userspace might have messed up non-PI and
+			 * PI futexes [3]
 			 */
 			if (unlikely(!pi_state))
 				return -EINVAL;
@@ -752,34 +818,70 @@ lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
 			WARN_ON(!atomic_read(&pi_state->refcount));
 
 			/*
-			 * When pi_state->owner is NULL then the owner died
-			 * and another waiter is on the fly. pi_state->owner
-			 * is fixed up by the task which acquires
-			 * pi_state->rt_mutex.
-			 *
-			 * We do not check for pid == 0 which can happen when
-			 * the owner died and robust_list_exit() cleared the
-			 * TID.
+			 * Handle the owner died case:
 			 */
-			if (pid && pi_state->owner) {
+			if (uval & FUTEX_OWNER_DIED) {
+				/*
+				 * exit_pi_state_list sets owner to NULL and
+				 * wakes the topmost waiter. The task which
+				 * acquires the pi_state->rt_mutex will fixup
+				 * owner.
+				 */
+				if (!pi_state->owner) {
+					/*
+					 * No pi state owner, but the user
+					 * space TID is not 0. Inconsistent
+					 * state. [5]
+					 */
+					if (pid)
+						return -EINVAL;
+					/*
+					 * Take a ref on the state and
+					 * return. [4]
+					 */
+					goto out_state;
+				}
+
 				/*
-				 * Bail out if user space manipulated the
-				 * futex value.
+				 * If TID is 0, then either the dying owner
+				 * has not yet executed exit_pi_state_list()
+				 * or some waiter acquired the rtmutex in the
+				 * pi state, but did not yet fixup the TID in
+				 * user space.
+				 *
+				 * Take a ref on the state and return. [6]
 				 */
-				if (pid != task_pid_vnr(pi_state->owner))
+				if (!pid)
+					goto out_state;
+			} else {
+				/*
+				 * If the owner died bit is not set,
+				 * then the pi_state must have an
+				 * owner. [7]
+				 */
+				if (!pi_state->owner)
 					return -EINVAL;
 			}
 
+			/*
+			 * Bail out if user space manipulated the
+			 * futex value. If pi state exists then the
+			 * owner TID must be the same as the user
+			 * space TID. [9/10]
+			 */
+			if (pid != task_pid_vnr(pi_state->owner))
+				return -EINVAL;
+
+		out_state:
 			atomic_inc(&pi_state->refcount);
 			*ps = pi_state;
-
 			return 0;
 		}
 	}
 
 	/*
 	 * We are the first waiter - try to look up the real owner and attach
-	 * the new pi_state to it, but bail out when TID = 0
+	 * the new pi_state to it, but bail out when TID = 0 [1]
 	 */
 	if (!pid)
 		return -ESRCH;
@@ -787,6 +889,11 @@ lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
 	if (!p)
 		return -ESRCH;
 
+	if (!p->mm) {
+		put_task_struct(p);
+		return -EPERM;
+	}
+
 	/*
 	 * We need to look at the task state flags to figure out,
 	 * whether the task is exiting. To protect against the do_exit
@@ -807,6 +914,9 @@ lookup_pi_state(u32 uval, struct futex_hash_bucket *hb,
 		return ret;
 	}
 
+	/*
+	 * No existing pi state. First waiter. [2]
+	 */
 	pi_state = alloc_pi_state();
 
 	/*
@@ -878,10 +988,18 @@ retry:
 		return -EDEADLK;
 
 	/*
-	 * Surprise - we got the lock. Just return to userspace:
+	 * Surprise - we got the lock, but we do not trust user space at all.
 	 */
-	if (unlikely(!curval))
-		return 1;
+	if (unlikely(!curval)) {
+		/*
+		 * We verify whether there is kernel state for this
+		 * futex. If not, we can safely assume, that the 0 ->
+		 * TID transition is correct. If state exists, we do
+		 * not bother to fixup the user space state as it was
+		 * corrupted already.
+		 */
+		return futex_top_waiter(hb, key) ? -EINVAL : 1;
+	}
 
 	uval = curval;
 
@@ -1012,6 +1130,7 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this)
 	struct task_struct *new_owner;
 	struct futex_pi_state *pi_state = this->pi_state;
 	u32 uninitialized_var(curval), newval;
+	int ret = 0;
 
 	if (!pi_state)
 		return -EINVAL;
@@ -1035,23 +1154,19 @@ static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_q *this)
 		new_owner = this->task;
 
 	/*
-	 * We pass it to the next owner. (The WAITERS bit is always
-	 * kept enabled while there is PI state around. We must also
-	 * preserve the owner died bit.)
+	 * We pass it to the next owner. The WAITERS bit is always
+	 * kept enabled while there is PI state around. We cleanup the
+	 * owner died bit, because we are the owner.
 	 */
-	if (!(uval & FUTEX_OWNER_DIED)) {
-		int ret = 0;
+	newval = FUTEX_WAITERS | task_pid_vnr(new_owner);
 
-		newval = FUTEX_WAITERS | task_pid_vnr(new_owner);
-
-		if (cmpxchg_futex_value_locked(&curval, uaddr, uval, newval))
-			ret = -EFAULT;
-		else if (curval != uval)
-			ret = -EINVAL;
-		if (ret) {
-			raw_spin_unlock(&pi_state->pi_mutex.wait_lock);
-			return ret;
-		}
+	if (cmpxchg_futex_value_locked(&curval, uaddr, uval, newval))
+		ret = -EFAULT;
+	else if (curval != uval)
+		ret = -EINVAL;
+	if (ret) {
+		raw_spin_unlock(&pi_state->pi_mutex.wait_lock);
+		return ret;
 	}
 
 	raw_spin_lock_irq(&pi_state->owner->pi_lock);
@@ -1331,7 +1446,7 @@ void requeue_pi_wake_futex(struct futex_q *q, union futex_key *key,
  *
  * Return:
  *  0 - failed to acquire the lock atomically;
- *  1 - acquired the lock;
+ * >0 - acquired the lock, return value is vpid of the top_waiter
  * <0 - error
  */
 static int futex_proxy_trylock_atomic(u32 __user *pifutex,
@@ -1342,7 +1457,7 @@ static int futex_proxy_trylock_atomic(u32 __user *pifutex,
 {
 	struct futex_q *top_waiter = NULL;
 	u32 curval;
-	int ret;
+	int ret, vpid;
 
 	if (get_futex_value_locked(&curval, pifutex))
 		return -EFAULT;
@@ -1370,11 +1485,13 @@ static int futex_proxy_trylock_atomic(u32 __user *pifutex,
 	 * the contended case or if set_waiters is 1.  The pi_state is returned
 	 * in ps in contended cases.
 	 */
+	vpid = task_pid_vnr(top_waiter->task);
 	ret = futex_lock_pi_atomic(pifutex, hb2, key2, ps, top_waiter->task,
 				   set_waiters);
-	if (ret == 1)
+	if (ret == 1) {
 		requeue_pi_wake_futex(top_waiter, key2, hb2);
-
+		return vpid;
+	}
 	return ret;
 }
 
@@ -1405,10 +1522,16 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags,
 	struct futex_pi_state *pi_state = NULL;
 	struct futex_hash_bucket *hb1, *hb2;
 	struct futex_q *this, *next;
-	u32 curval2;
 
 	if (requeue_pi) {
 		/*
+		 * Requeue PI only works on two distinct uaddrs. This
+		 * check is only valid for private futexes. See below.
+		 */
+		if (uaddr1 == uaddr2)
+			return -EINVAL;
+
+		/*
 		 * requeue_pi requires a pi_state, try to allocate it now
 		 * without any locks in case it fails.
 		 */
@@ -1446,10 +1569,20 @@ retry:
 	if (unlikely(ret != 0))
 		goto out_put_key1;
 
+	/*
+	 * The check above which compares uaddrs is not sufficient for
+	 * shared futexes. We need to compare the keys:
+	 */
+	if (requeue_pi && match_futex(&key1, &key2)) {
+		ret = -EINVAL;
+		goto out_put_keys;
+	}
+
 	hb1 = hash_futex(&key1);
 	hb2 = hash_futex(&key2);
 
 retry_private:
+	hb_waiters_inc(hb2);
 	double_lock_hb(hb1, hb2);
 
 	if (likely(cmpval != NULL)) {
@@ -1459,6 +1592,7 @@ retry_private:
 
 		if (unlikely(ret)) {
 			double_unlock_hb(hb1, hb2);
+			hb_waiters_dec(hb2);
 
 			ret = get_user(curval, uaddr1);
 			if (ret)
@@ -1491,16 +1625,25 @@ retry_private:
 		 * At this point the top_waiter has either taken uaddr2 or is
 		 * waiting on it.  If the former, then the pi_state will not
 		 * exist yet, look it up one more time to ensure we have a
-		 * reference to it.
+		 * reference to it. If the lock was taken, ret contains the
+		 * vpid of the top waiter task.
 		 */
-		if (ret == 1) {
+		if (ret > 0) {
 			WARN_ON(pi_state);
 			drop_count++;
 			task_count++;
-			ret = get_futex_value_locked(&curval2, uaddr2);
-			if (!ret)
-				ret = lookup_pi_state(curval2, hb2, &key2,
-						      &pi_state);
+			/*
+			 * If we acquired the lock, then the user
+			 * space value of uaddr2 should be vpid. It
+			 * cannot be changed by the top waiter as it
+			 * is blocked on hb2 lock if it tries to do
+			 * so. If something fiddled with it behind our
+			 * back the pi state lookup might unearth
+			 * it. So we rather use the known value than
+			 * rereading and handing potential crap to
+			 * lookup_pi_state.
+			 */
+			ret = lookup_pi_state(ret, hb2, &key2, &pi_state);
 		}
 
 		switch (ret) {
@@ -1508,6 +1651,7 @@ retry_private:
 			break;
 		case -EFAULT:
 			double_unlock_hb(hb1, hb2);
+			hb_waiters_dec(hb2);
 			put_futex_key(&key2);
 			put_futex_key(&key1);
 			ret = fault_in_user_writeable(uaddr2);
@@ -1517,6 +1661,7 @@ retry_private:
 		case -EAGAIN:
 			/* The owner was exiting, try again. */
 			double_unlock_hb(hb1, hb2);
+			hb_waiters_dec(hb2);
 			put_futex_key(&key2);
 			put_futex_key(&key1);
 			cond_resched();
@@ -1592,6 +1737,7 @@ retry_private:
 
 out_unlock:
 	double_unlock_hb(hb1, hb2);
+	hb_waiters_dec(hb2);
 
 	/*
 	 * drop_futex_key_refs() must be called outside the spinlocks. During
@@ -2280,9 +2426,10 @@ retry:
 	/*
 	 * To avoid races, try to do the TID -> 0 atomic transition
 	 * again. If it succeeds then we can return without waking
-	 * anyone else up:
+	 * anyone else up. We only try this if neither the waiters nor
+	 * the owner died bit are set.
 	 */
-	if (!(uval & FUTEX_OWNER_DIED) &&
+	if (!(uval & ~FUTEX_TID_MASK) &&
 	    cmpxchg_futex_value_locked(&uval, uaddr, vpid, 0))
 		goto pi_faulted;
 	/*
@@ -2312,11 +2459,9 @@ retry:
 	/*
 	 * No waiters - kernel unlocks the futex:
 	 */
-	if (!(uval & FUTEX_OWNER_DIED)) {
-		ret = unlock_futex_pi(uaddr, uval);
-		if (ret == -EFAULT)
-			goto pi_faulted;
-	}
+	ret = unlock_futex_pi(uaddr, uval);
+	if (ret == -EFAULT)
+		goto pi_faulted;
 
 out_unlock:
 	spin_unlock(&hb->lock);
@@ -2478,6 +2623,15 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
 	if (ret)
 		goto out_key2;
 
+	/*
+	 * The check above which compares uaddrs is not sufficient for
+	 * shared futexes. We need to compare the keys:
+	 */
+	if (match_futex(&q.key, &key2)) {
+		ret = -EINVAL;
+		goto out_put_keys;
+	}
+
 	/* Queue the futex_q, drop the hb lock, wait for wakeup. */
 	futex_wait_queue_me(hb, &q, to);
 
@@ -2875,9 +3029,28 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
 	return do_futex(uaddr, op, val, tp, uaddr2, val2, val3);
 }
 
-static int __init futex_init(void)
+static void __init futex_detect_cmpxchg(void)
 {
+#ifndef CONFIG_HAVE_FUTEX_CMPXCHG
 	u32 curval;
+
+	/*
+	 * This will fail and we want it. Some arch implementations do
+	 * runtime detection of the futex_atomic_cmpxchg_inatomic()
+	 * functionality. We want to know that before we call in any
+	 * of the complex code paths. Also we want to prevent
+	 * registration of robust lists in that case. NULL is
+	 * guaranteed to fault and we get -EFAULT on functional
+	 * implementation, the non-functional ones will return
+	 * -ENOSYS.
+	 */
+	if (cmpxchg_futex_value_locked(&curval, NULL, 0, 0) == -EFAULT)
+		futex_cmpxchg_enabled = 1;
+#endif
+}
+
+static int __init futex_init(void)
+{
 	unsigned int futex_shift;
 	unsigned long i;
 
@@ -2893,18 +3066,8 @@ static int __init futex_init(void)
 					       &futex_shift, NULL,
 					       futex_hashsize, futex_hashsize);
 	futex_hashsize = 1UL << futex_shift;
-	/*
-	 * This will fail and we want it. Some arch implementations do
-	 * runtime detection of the futex_atomic_cmpxchg_inatomic()
-	 * functionality. We want to know that before we call in any
-	 * of the complex code paths. Also we want to prevent
-	 * registration of robust lists in that case. NULL is
-	 * guaranteed to fault and we get -EFAULT on functional
-	 * implementation, the non-functional ones will return
-	 * -ENOSYS.
-	 */
-	if (cmpxchg_futex_value_locked(&curval, NULL, 0, 0) == -EFAULT)
-		futex_cmpxchg_enabled = 1;
+
+	futex_detect_cmpxchg();
 
 	for (i = 0; i < futex_hashsize; i++) {
 		atomic_set(&futex_queues[i].waiters, 0);
diff --git a/kernel/futex_compat.c b/kernel/futex_compat.c
index f9f44fd4d34d..55c8c9349cfe 100644
--- a/kernel/futex_compat.c
+++ b/kernel/futex_compat.c
@@ -183,7 +183,7 @@ COMPAT_SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
 	if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI ||
 		      cmd == FUTEX_WAIT_BITSET ||
 		      cmd == FUTEX_WAIT_REQUEUE_PI)) {
-		if (get_compat_timespec(&ts, utime))
+		if (compat_get_timespec(&ts, utime))
 			return -EFAULT;
 		if (!timespec_valid(&ts))
 			return -EINVAL;
diff --git a/kernel/groups.c b/kernel/groups.c
index 90cf1c38c8ea..451698f86cfa 100644
--- a/kernel/groups.c
+++ b/kernel/groups.c
@@ -157,17 +157,13 @@ int groups_search(const struct group_info *group_info, kgid_t grp)
  * set_groups - Change a group subscription in a set of credentials
  * @new: The newly prepared set of credentials to alter
  * @group_info: The group list to install
- *
- * Validate a group subscription and, if valid, insert it into a set
- * of credentials.
  */
-int set_groups(struct cred *new, struct group_info *group_info)
+void set_groups(struct cred *new, struct group_info *group_info)
 {
 	put_group_info(new->group_info);
 	groups_sort(group_info);
 	get_group_info(group_info);
 	new->group_info = group_info;
-	return 0;
 }
 
 EXPORT_SYMBOL(set_groups);
@@ -182,18 +178,12 @@ EXPORT_SYMBOL(set_groups);
 int set_current_groups(struct group_info *group_info)
 {
 	struct cred *new;
-	int ret;
 
 	new = prepare_creds();
 	if (!new)
 		return -ENOMEM;
 
-	ret = set_groups(new, group_info);
-	if (ret < 0) {
-		abort_creds(new);
-		return ret;
-	}
-
+	set_groups(new, group_info);
 	return commit_creds(new);
 }
 
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 09094361dce5..e0501fe7140d 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -168,19 +168,6 @@ struct hrtimer_clock_base *lock_hrtimer_base(const struct hrtimer *timer,
 	}
 }
 
-
-/*
- * Get the preferred target CPU for NOHZ
- */
-static int hrtimer_get_target(int this_cpu, int pinned)
-{
-#ifdef CONFIG_NO_HZ_COMMON
-	if (!pinned && get_sysctl_timer_migration() && idle_cpu(this_cpu))
-		return get_nohz_timer_target();
-#endif
-	return this_cpu;
-}
-
 /*
  * With HIGHRES=y we do not migrate the timer when it is expiring
  * before the next event on the target cpu because we cannot reprogram
@@ -214,7 +201,7 @@ switch_hrtimer_base(struct hrtimer *timer, struct hrtimer_clock_base *base,
 	struct hrtimer_clock_base *new_base;
 	struct hrtimer_cpu_base *new_cpu_base;
 	int this_cpu = smp_processor_id();
-	int cpu = hrtimer_get_target(this_cpu, pinned);
+	int cpu = get_nohz_timer_target(pinned);
 	int basenum = base->index;
 
 again:
@@ -247,6 +234,11 @@ again:
 			goto again;
 		}
 		timer->base = new_base;
+	} else {
+		if (cpu != this_cpu && hrtimer_check_target(timer, new_base)) {
+			cpu = this_cpu;
+			goto again;
+		}
 	}
 	return new_base;
 }
@@ -582,6 +574,23 @@ hrtimer_force_reprogram(struct hrtimer_cpu_base *cpu_base, int skip_equal)
 
 	cpu_base->expires_next.tv64 = expires_next.tv64;
 
+	/*
+	 * If a hang was detected in the last timer interrupt then we
+	 * leave the hang delay active in the hardware. We want the
+	 * system to make progress. That also prevents the following
+	 * scenario:
+	 * T1 expires 50ms from now
+	 * T2 expires 5s from now
+	 *
+	 * T1 is removed, so this code is called and would reprogram
+	 * the hardware to 5s from now. Any hrtimer_start after that
+	 * will not reprogram the hardware due to hang_detected being
+	 * set. So we'd effectivly block all timers until the T2 event
+	 * fires.
+	 */
+	if (cpu_base->hang_detected)
+		return;
+
 	if (cpu_base->expires_next.tv64 != KTIME_MAX)
 		tick_program_event(cpu_base->expires_next, 1);
 }
@@ -981,11 +990,8 @@ int __hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
 	/* Remove an active timer from the queue: */
 	ret = remove_hrtimer(timer, base);
 
-	/* Switch the timer base, if necessary: */
-	new_base = switch_hrtimer_base(timer, base, mode & HRTIMER_MODE_PINNED);
-
 	if (mode & HRTIMER_MODE_REL) {
-		tim = ktime_add_safe(tim, new_base->get_time());
+		tim = ktime_add_safe(tim, base->get_time());
 		/*
 		 * CONFIG_TIME_LOW_RES is a temporary way for architectures
 		 * to signal that they simply return xtime in
@@ -1000,6 +1006,9 @@ int __hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
 
 	hrtimer_set_expires_range_ns(timer, tim, delta_ns);
 
+	/* Switch the timer base, if necessary: */
+	new_base = switch_hrtimer_base(timer, base, mode & HRTIMER_MODE_PINNED);
+
 	timer_stats_hrtimer_set_start_info(timer);
 
 	leftmost = enqueue_hrtimer(timer, new_base);
diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index 0b9c169d577f..06bb1417b063 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -246,5 +246,4 @@ static int __init hung_task_init(void)
 
 	return 0;
 }
-
-module_init(hung_task_init);
+subsys_initcall(hung_task_init);
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index dc04c166c54d..6397df2d6945 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -281,6 +281,19 @@ void unmask_irq(struct irq_desc *desc)
 	}
 }
 
+void unmask_threaded_irq(struct irq_desc *desc)
+{
+	struct irq_chip *chip = desc->irq_data.chip;
+
+	if (chip->flags & IRQCHIP_EOI_THREADED)
+		chip->irq_eoi(&desc->irq_data);
+
+	if (chip->irq_unmask) {
+		chip->irq_unmask(&desc->irq_data);
+		irq_state_clr_masked(desc);
+	}
+}
+
 /*
  *	handle_nested_irq - Handle a nested irq from a irq thread
  *	@irq:	the interrupt number
@@ -435,6 +448,27 @@ static inline void preflow_handler(struct irq_desc *desc)
 static inline void preflow_handler(struct irq_desc *desc) { }
 #endif
 
+static void cond_unmask_eoi_irq(struct irq_desc *desc, struct irq_chip *chip)
+{
+	if (!(desc->istate & IRQS_ONESHOT)) {
+		chip->irq_eoi(&desc->irq_data);
+		return;
+	}
+	/*
+	 * We need to unmask in the following cases:
+	 * - Oneshot irq which did not wake the thread (caused by a
+	 *   spurious interrupt or a primary handler handling it
+	 *   completely).
+	 */
+	if (!irqd_irq_disabled(&desc->irq_data) &&
+	    irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot) {
+		chip->irq_eoi(&desc->irq_data);
+		unmask_irq(desc);
+	} else if (!(chip->flags & IRQCHIP_EOI_THREADED)) {
+		chip->irq_eoi(&desc->irq_data);
+	}
+}
+
 /**
  *	handle_fasteoi_irq - irq handler for transparent controllers
  *	@irq:	the interrupt number
@@ -448,6 +482,8 @@ static inline void preflow_handler(struct irq_desc *desc) { }
 void
 handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
 {
+	struct irq_chip *chip = desc->irq_data.chip;
+
 	raw_spin_lock(&desc->lock);
 
 	if (unlikely(irqd_irq_inprogress(&desc->irq_data)))
@@ -473,18 +509,14 @@ handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
 	preflow_handler(desc);
 	handle_irq_event(desc);
 
-	if (desc->istate & IRQS_ONESHOT)
-		cond_unmask_irq(desc);
+	cond_unmask_eoi_irq(desc, chip);
 
-out_eoi:
-	desc->irq_data.chip->irq_eoi(&desc->irq_data);
-out_unlock:
 	raw_spin_unlock(&desc->lock);
 	return;
 out:
-	if (!(desc->irq_data.chip->flags & IRQCHIP_EOI_IF_HANDLED))
-		goto out_eoi;
-	goto out_unlock;
+	if (!(chip->flags & IRQCHIP_EOI_IF_HANDLED))
+		chip->irq_eoi(&desc->irq_data);
+	raw_spin_unlock(&desc->lock);
 }
 
 /**
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 131ca176b497..635480270858 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -41,6 +41,7 @@ irqreturn_t no_action(int cpl, void *dev_id)
 {
 	return IRQ_NONE;
 }
+EXPORT_SYMBOL_GPL(no_action);
 
 static void warn_no_thread(unsigned int irq, struct irqaction *action)
 {
@@ -51,7 +52,7 @@ static void warn_no_thread(unsigned int irq, struct irqaction *action)
 	       "but no thread function available.", irq, action->name);
 }
 
-static void irq_wake_thread(struct irq_desc *desc, struct irqaction *action)
+void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action)
 {
 	/*
 	 * In case the thread crashed and was killed we just pretend that
@@ -157,7 +158,7 @@ handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action)
 				break;
 			}
 
-			irq_wake_thread(desc, action);
+			__irq_wake_thread(desc, action);
 
 			/* Fall through to add to randomness */
 		case IRQ_HANDLED:
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index 001fa5bab490..ddf1ffeb79f1 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -6,6 +6,7 @@
  * of this file for your non core code.
  */
 #include <linux/irqdesc.h>
+#include <linux/kernel_stat.h>
 
 #ifdef CONFIG_SPARSE_IRQ
 # define IRQ_BITMAP_BITS	(NR_IRQS + 8196)
@@ -73,6 +74,7 @@ extern void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu);
 extern void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu);
 extern void mask_irq(struct irq_desc *desc);
 extern void unmask_irq(struct irq_desc *desc);
+extern void unmask_threaded_irq(struct irq_desc *desc);
 
 extern void init_kstat_irqs(struct irq_desc *desc, int node, int nr);
 
@@ -82,6 +84,7 @@ irqreturn_t handle_irq_event(struct irq_desc *desc);
 /* Resending of interrupts :*/
 void check_irq_resend(struct irq_desc *desc, unsigned int irq);
 bool irq_wait_for_poll(struct irq_desc *desc);
+void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action);
 
 #ifdef CONFIG_PROC_FS
 extern void register_irq_proc(unsigned int irq, struct irq_desc *desc);
@@ -179,3 +182,9 @@ static inline bool irqd_has_set(struct irq_data *d, unsigned int mask)
 {
 	return d->state_use_accessors & mask;
 }
+
+static inline void kstat_incr_irqs_this_cpu(unsigned int irq, struct irq_desc *desc)
+{
+	__this_cpu_inc(*desc->kstat_irqs);
+	__this_cpu_inc(kstat.irqs_sum);
+}
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 8ab8e9390297..bb07f2928f4b 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -363,6 +363,13 @@ __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
 		if (from > irq)
 			return -EINVAL;
 		from = irq;
+	} else {
+		/*
+		 * For interrupts which are freely allocated the
+		 * architecture can force a lower bound to the @from
+		 * argument. x86 uses this to exclude the GSI space.
+		 */
+		from = arch_dynirq_lower_bound(from);
 	}
 
 	mutex_lock(&sparse_irq_lock);
@@ -489,6 +496,11 @@ void dynamic_irq_cleanup(unsigned int irq)
 	raw_spin_unlock_irqrestore(&desc->lock, flags);
 }
 
+void kstat_incr_irq_this_cpu(unsigned int irq)
+{
+	kstat_incr_irqs_this_cpu(irq, irq_to_desc(irq));
+}
+
 unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index d3bf660cb57f..d34131ca372b 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -32,24 +32,10 @@ static int __init setup_forced_irqthreads(char *arg)
 early_param("threadirqs", setup_forced_irqthreads);
 #endif
 
-/**
- *	synchronize_irq - wait for pending IRQ handlers (on other CPUs)
- *	@irq: interrupt number to wait for
- *
- *	This function waits for any pending IRQ handlers for this interrupt
- *	to complete before returning. If you use this function while
- *	holding a resource the IRQ handler may need you will deadlock.
- *
- *	This function may be called - with care - from IRQ context.
- */
-void synchronize_irq(unsigned int irq)
+static void __synchronize_hardirq(struct irq_desc *desc)
 {
-	struct irq_desc *desc = irq_to_desc(irq);
 	bool inprogress;
 
-	if (!desc)
-		return;
-
 	do {
 		unsigned long flags;
 
@@ -67,12 +53,56 @@ void synchronize_irq(unsigned int irq)
 
 		/* Oops, that failed? */
 	} while (inprogress);
+}
 
-	/*
-	 * We made sure that no hardirq handler is running. Now verify
-	 * that no threaded handlers are active.
-	 */
-	wait_event(desc->wait_for_threads, !atomic_read(&desc->threads_active));
+/**
+ *	synchronize_hardirq - wait for pending hard IRQ handlers (on other CPUs)
+ *	@irq: interrupt number to wait for
+ *
+ *	This function waits for any pending hard IRQ handlers for this
+ *	interrupt to complete before returning. If you use this
+ *	function while holding a resource the IRQ handler may need you
+ *	will deadlock. It does not take associated threaded handlers
+ *	into account.
+ *
+ *	Do not use this for shutdown scenarios where you must be sure
+ *	that all parts (hardirq and threaded handler) have completed.
+ *
+ *	This function may be called - with care - from IRQ context.
+ */
+void synchronize_hardirq(unsigned int irq)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+
+	if (desc)
+		__synchronize_hardirq(desc);
+}
+EXPORT_SYMBOL(synchronize_hardirq);
+
+/**
+ *	synchronize_irq - wait for pending IRQ handlers (on other CPUs)
+ *	@irq: interrupt number to wait for
+ *
+ *	This function waits for any pending IRQ handlers for this interrupt
+ *	to complete before returning. If you use this function while
+ *	holding a resource the IRQ handler may need you will deadlock.
+ *
+ *	This function may be called - with care - from IRQ context.
+ */
+void synchronize_irq(unsigned int irq)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+
+	if (desc) {
+		__synchronize_hardirq(desc);
+		/*
+		 * We made sure that no hardirq handler is
+		 * running. Now verify that no threaded handlers are
+		 * active.
+		 */
+		wait_event(desc->wait_for_threads,
+			   !atomic_read(&desc->threads_active));
+	}
 }
 EXPORT_SYMBOL(synchronize_irq);
 
@@ -150,7 +180,7 @@ int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
 	struct irq_chip *chip = irq_data_get_irq_chip(data);
 	int ret;
 
-	ret = chip->irq_set_affinity(data, mask, false);
+	ret = chip->irq_set_affinity(data, mask, force);
 	switch (ret) {
 	case IRQ_SET_MASK_OK:
 		cpumask_copy(data->affinity, mask);
@@ -162,7 +192,8 @@ int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
 	return ret;
 }
 
-int __irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask)
+int irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask,
+			    bool force)
 {
 	struct irq_chip *chip = irq_data_get_irq_chip(data);
 	struct irq_desc *desc = irq_data_to_desc(data);
@@ -172,7 +203,7 @@ int __irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask)
 		return -EINVAL;
 
 	if (irq_can_move_pcntxt(data)) {
-		ret = irq_do_set_affinity(data, mask, false);
+		ret = irq_do_set_affinity(data, mask, force);
 	} else {
 		irqd_set_move_pending(data);
 		irq_copy_pending(desc, mask);
@@ -187,13 +218,7 @@ int __irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask)
 	return ret;
 }
 
-/**
- *	irq_set_affinity - Set the irq affinity of a given irq
- *	@irq:		Interrupt to set affinity
- *	@mask:		cpumask
- *
- */
-int irq_set_affinity(unsigned int irq, const struct cpumask *mask)
+int __irq_set_affinity(unsigned int irq, const struct cpumask *mask, bool force)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
 	unsigned long flags;
@@ -203,7 +228,7 @@ int irq_set_affinity(unsigned int irq, const struct cpumask *mask)
 		return -EINVAL;
 
 	raw_spin_lock_irqsave(&desc->lock, flags);
-	ret =  __irq_set_affinity_locked(irq_desc_get_irq_data(desc), mask);
+	ret = irq_set_affinity_locked(irq_desc_get_irq_data(desc), mask, force);
 	raw_spin_unlock_irqrestore(&desc->lock, flags);
 	return ret;
 }
@@ -718,7 +743,7 @@ again:
 
 	if (!desc->threads_oneshot && !irqd_irq_disabled(&desc->irq_data) &&
 	    irqd_irq_masked(&desc->irq_data))
-		unmask_irq(desc);
+		unmask_threaded_irq(desc);
 
 out_unlock:
 	raw_spin_unlock_irq(&desc->lock);
@@ -727,7 +752,7 @@ out_unlock:
 
 #ifdef CONFIG_SMP
 /*
- * Check whether we need to chasnge the affinity of the interrupt thread.
+ * Check whether we need to change the affinity of the interrupt thread.
  */
 static void
 irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
@@ -880,6 +905,33 @@ static int irq_thread(void *data)
 	return 0;
 }
 
+/**
+ *	irq_wake_thread - wake the irq thread for the action identified by dev_id
+ *	@irq:		Interrupt line
+ *	@dev_id:	Device identity for which the thread should be woken
+ *
+ */
+void irq_wake_thread(unsigned int irq, void *dev_id)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+	struct irqaction *action;
+	unsigned long flags;
+
+	if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc)))
+		return;
+
+	raw_spin_lock_irqsave(&desc->lock, flags);
+	for (action = desc->action; action; action = action->next) {
+		if (action->dev_id == dev_id) {
+			if (action->thread)
+				__irq_wake_thread(desc, action);
+			break;
+		}
+	}
+	raw_spin_unlock_irqrestore(&desc->lock, flags);
+}
+EXPORT_SYMBOL_GPL(irq_wake_thread);
+
 static void irq_setup_forced_threading(struct irqaction *new)
 {
 	if (!force_irqthreads)
@@ -896,6 +948,23 @@ static void irq_setup_forced_threading(struct irqaction *new)
 	}
 }
 
+static int irq_request_resources(struct irq_desc *desc)
+{
+	struct irq_data *d = &desc->irq_data;
+	struct irq_chip *c = d->chip;
+
+	return c->irq_request_resources ? c->irq_request_resources(d) : 0;
+}
+
+static void irq_release_resources(struct irq_desc *desc)
+{
+	struct irq_data *d = &desc->irq_data;
+	struct irq_chip *c = d->chip;
+
+	if (c->irq_release_resources)
+		c->irq_release_resources(d);
+}
+
 /*
  * Internal function to register an irqaction - typically used to
  * allocate special interrupts that are part of the architecture.
@@ -1091,6 +1160,13 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 	}
 
 	if (!shared) {
+		ret = irq_request_resources(desc);
+		if (ret) {
+			pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",
+			       new->name, irq, desc->irq_data.chip->name);
+			goto out_mask;
+		}
+
 		init_waitqueue_head(&desc->wait_for_threads);
 
 		/* Setup the type (level, edge polarity) if configured: */
@@ -1261,8 +1337,10 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
 	*action_ptr = action->next;
 
 	/* If this was the last handler, shut down the IRQ line: */
-	if (!desc->action)
+	if (!desc->action) {
 		irq_shutdown(desc);
+		irq_release_resources(desc);
+	}
 
 #ifdef CONFIG_SMP
 	/* make sure affinity_hint is cleaned up */
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index 36f6ee181b0c..ac1ba2f11032 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -324,15 +324,15 @@ void register_irq_proc(unsigned int irq, struct irq_desc *desc)
 
 #ifdef CONFIG_SMP
 	/* create /proc/irq/<irq>/smp_affinity */
-	proc_create_data("smp_affinity", 0600, desc->dir,
+	proc_create_data("smp_affinity", 0644, desc->dir,
 			 &irq_affinity_proc_fops, (void *)(long)irq);
 
 	/* create /proc/irq/<irq>/affinity_hint */
-	proc_create_data("affinity_hint", 0400, desc->dir,
+	proc_create_data("affinity_hint", 0444, desc->dir,
 			 &irq_affinity_hint_proc_fops, (void *)(long)irq);
 
 	/* create /proc/irq/<irq>/smp_affinity_list */
-	proc_create_data("smp_affinity_list", 0600, desc->dir,
+	proc_create_data("smp_affinity_list", 0644, desc->dir,
 			 &irq_affinity_list_proc_fops, (void *)(long)irq);
 
 	proc_create_data("node", 0444, desc->dir,
@@ -372,7 +372,7 @@ void unregister_handler_proc(unsigned int irq, struct irqaction *action)
 static void register_default_affinity_proc(void)
 {
 #ifdef CONFIG_SMP
-	proc_create("irq/default_smp_affinity", 0600, NULL,
+	proc_create("irq/default_smp_affinity", 0644, NULL,
 		    &default_affinity_proc_fops);
 #endif
 }
diff --git a/kernel/irq_work.c b/kernel/irq_work.c
index 55fcce6065cf..a82170e2fa78 100644
--- a/kernel/irq_work.c
+++ b/kernel/irq_work.c
@@ -61,11 +61,11 @@ void __weak arch_irq_work_raise(void)
  *
  * Can be re-enqueued while the callback is still in progress.
  */
-void irq_work_queue(struct irq_work *work)
+bool irq_work_queue(struct irq_work *work)
 {
 	/* Only queue if not already pending */
 	if (!irq_work_claim(work))
-		return;
+		return false;
 
 	/* Queue the entry and raise the IPI if needed. */
 	preempt_disable();
@@ -83,6 +83,8 @@ void irq_work_queue(struct irq_work *work)
 	}
 
 	preempt_enable();
+
+	return true;
 }
 EXPORT_SYMBOL_GPL(irq_work_queue);
 
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 3127ad52cdb2..cb0cf37dac3a 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -23,6 +23,7 @@
 #include <linux/mm.h>
 #include <linux/ctype.h>
 #include <linux/slab.h>
+#include <linux/compiler.h>
 
 #include <asm/sections.h>
 
@@ -36,8 +37,8 @@
  * These will be re-linked against their real values
  * during the second link stage.
  */
-extern const unsigned long kallsyms_addresses[] __attribute__((weak));
-extern const u8 kallsyms_names[] __attribute__((weak));
+extern const unsigned long kallsyms_addresses[] __weak;
+extern const u8 kallsyms_names[] __weak;
 
 /*
  * Tell the compiler that the count isn't in the small data section if the arch
@@ -46,10 +47,10 @@ extern const u8 kallsyms_names[] __attribute__((weak));
 extern const unsigned long kallsyms_num_syms
 __attribute__((weak, section(".rodata")));
 
-extern const u8 kallsyms_token_table[] __attribute__((weak));
-extern const u16 kallsyms_token_index[] __attribute__((weak));
+extern const u8 kallsyms_token_table[] __weak;
+extern const u16 kallsyms_token_index[] __weak;
 
-extern const unsigned long kallsyms_markers[] __attribute__((weak));
+extern const unsigned long kallsyms_markers[] __weak;
 
 static inline int is_kernel_inittext(unsigned long addr)
 {
diff --git a/kernel/kexec.c b/kernel/kexec.c
index 60bafbed06ab..28c57069ef68 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -32,6 +32,7 @@
 #include <linux/vmalloc.h>
 #include <linux/swap.h>
 #include <linux/syscore_ops.h>
+#include <linux/compiler.h>
 
 #include <asm/page.h>
 #include <asm/uaccess.h>
@@ -1039,10 +1040,10 @@ void __weak crash_unmap_reserved_pages(void)
 {}
 
 #ifdef CONFIG_COMPAT
-asmlinkage long compat_sys_kexec_load(unsigned long entry,
-				unsigned long nr_segments,
-				struct compat_kexec_segment __user *segments,
-				unsigned long flags)
+COMPAT_SYSCALL_DEFINE4(kexec_load, compat_ulong_t, entry,
+		       compat_ulong_t, nr_segments,
+		       struct compat_kexec_segment __user *, segments,
+		       compat_ulong_t, flags)
 {
 	struct compat_kexec_segment in;
 	struct kexec_segment out, __user *ksegments;
@@ -1235,7 +1236,7 @@ static int __init crash_notes_memory_init(void)
 	}
 	return 0;
 }
-module_init(crash_notes_memory_init)
+subsys_initcall(crash_notes_memory_init);
 
 
 /*
@@ -1551,10 +1552,10 @@ void vmcoreinfo_append_str(const char *fmt, ...)
  * provide an empty default implementation here -- architecture
  * code may override this
  */
-void __attribute__ ((weak)) arch_crash_save_vmcoreinfo(void)
+void __weak arch_crash_save_vmcoreinfo(void)
 {}
 
-unsigned long __attribute__ ((weak)) paddr_vmcoreinfo_note(void)
+unsigned long __weak paddr_vmcoreinfo_note(void)
 {
 	return __pa((unsigned long)(char *)&vmcoreinfo_note);
 }
@@ -1629,7 +1630,7 @@ static int __init crash_save_vmcoreinfo_init(void)
 	return 0;
 }
 
-module_init(crash_save_vmcoreinfo_init)
+subsys_initcall(crash_save_vmcoreinfo_init);
 
 /*
  * Move into place and start executing a preloaded standalone
@@ -1682,6 +1683,14 @@ int kernel_kexec(void)
 		kexec_in_progress = true;
 		kernel_restart_prepare(NULL);
 		migrate_to_reboot_cpu();
+
+		/*
+		 * migrate_to_reboot_cpu() disables CPU hotplug assuming that
+		 * no further code needs to use CPU hotplug (which is true in
+		 * the reboot case). However, the kexec path depends on using
+		 * CPU hotplug again; so re-enable it here.
+		 */
+		cpu_hotplug_enable();
 		printk(KERN_EMERG "Starting new kernel\n");
 		machine_shutdown();
 	}
diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
index d945a949760f..2495a9b14ac8 100644
--- a/kernel/ksysfs.c
+++ b/kernel/ksysfs.c
@@ -18,6 +18,9 @@
 #include <linux/stat.h>
 #include <linux/sched.h>
 #include <linux/capability.h>
+#include <linux/compiler.h>
+
+#include <linux/rcupdate.h>	/* rcu_expedited */
 
 #define KERNEL_ATTR_RO(_name) \
 static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
@@ -160,8 +163,8 @@ KERNEL_ATTR_RW(rcu_expedited);
 /*
  * Make /sys/kernel/notes give the raw contents of our kernel .notes section.
  */
-extern const void __start_notes __attribute__((weak));
-extern const void __stop_notes __attribute__((weak));
+extern const void __start_notes __weak;
+extern const void __stop_notes __weak;
 #define	notes_size (&__stop_notes - &__start_notes)
 
 static ssize_t notes_read(struct file *filp, struct kobject *kobj,
diff --git a/kernel/kthread.c b/kernel/kthread.c
index b5ae3ee860a9..9a130ec06f7a 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -217,7 +217,7 @@ int tsk_fork_get_node(struct task_struct *tsk)
 	if (tsk == kthreadd_task)
 		return tsk->pref_node_fork;
 #endif
-	return numa_node_id();
+	return NUMA_NO_NODE;
 }
 
 static void create_kthread(struct kthread_create_info *create)
@@ -369,7 +369,7 @@ struct task_struct *kthread_create_on_cpu(int (*threadfn)(void *data),
 {
 	struct task_struct *p;
 
-	p = kthread_create_on_node(threadfn, data, cpu_to_node(cpu), namefmt,
+	p = kthread_create_on_node(threadfn, data, cpu_to_mem(cpu), namefmt,
 				   cpu);
 	if (IS_ERR(p))
 		return p;
diff --git a/kernel/locking/Makefile b/kernel/locking/Makefile
index baab8e5e7f66..b8bdcd4785b7 100644
--- a/kernel/locking/Makefile
+++ b/kernel/locking/Makefile
@@ -1,5 +1,5 @@
 
-obj-y += mutex.o semaphore.o rwsem.o lglock.o
+obj-y += mutex.o semaphore.o rwsem.o mcs_spinlock.o
 
 ifdef CONFIG_FUNCTION_TRACER
 CFLAGS_REMOVE_lockdep.o = -pg
@@ -14,6 +14,7 @@ ifeq ($(CONFIG_PROC_FS),y)
 obj-$(CONFIG_LOCKDEP) += lockdep_proc.o
 endif
 obj-$(CONFIG_SMP) += spinlock.o
+obj-$(CONFIG_SMP) += lglock.o
 obj-$(CONFIG_PROVE_LOCKING) += spinlock.o
 obj-$(CONFIG_RT_MUTEXES) += rtmutex.o
 obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o
@@ -23,3 +24,4 @@ obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock_debug.o
 obj-$(CONFIG_RWSEM_GENERIC_SPINLOCK) += rwsem-spinlock.o
 obj-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem-xadd.o
 obj-$(CONFIG_PERCPU_RWSEM) += percpu-rwsem.o
+obj-$(CONFIG_LOCK_TORTURE_TEST) += locktorture.o
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index eb8a54783fa0..d24e4339b46d 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -1936,12 +1936,12 @@ check_prevs_add(struct task_struct *curr, struct held_lock *next)
 
 	for (;;) {
 		int distance = curr->lockdep_depth - depth + 1;
-		hlock = curr->held_locks + depth-1;
+		hlock = curr->held_locks + depth - 1;
 		/*
 		 * Only non-recursive-read entries get new dependencies
 		 * added:
 		 */
-		if (hlock->read != 2) {
+		if (hlock->read != 2 && hlock->check) {
 			if (!check_prev_add(curr, hlock, next,
 						distance, trylock_loop))
 				return 0;
@@ -2098,7 +2098,7 @@ static int validate_chain(struct task_struct *curr, struct lockdep_map *lock,
 	 * (If lookup_chain_cache() returns with 1 it acquires
 	 * graph_lock for us)
 	 */
-	if (!hlock->trylock && (hlock->check == 2) &&
+	if (!hlock->trylock && hlock->check &&
 	    lookup_chain_cache(curr, hlock, chain_key)) {
 		/*
 		 * Check whether last held lock:
@@ -2517,7 +2517,7 @@ mark_held_locks(struct task_struct *curr, enum mark_type mark)
 
 		BUG_ON(usage_bit >= LOCK_USAGE_STATES);
 
-		if (hlock_class(hlock)->key == __lockdep_no_validate__.subkeys)
+		if (!hlock->check)
 			continue;
 
 		if (!mark_lock(curr, hlock, usage_bit))
@@ -2557,7 +2557,7 @@ static void __trace_hardirqs_on_caller(unsigned long ip)
 	debug_atomic_inc(hardirqs_on_events);
 }
 
-void trace_hardirqs_on_caller(unsigned long ip)
+__visible void trace_hardirqs_on_caller(unsigned long ip)
 {
 	time_hardirqs_on(CALLER_ADDR0, ip);
 
@@ -2610,7 +2610,7 @@ EXPORT_SYMBOL(trace_hardirqs_on);
 /*
  * Hardirqs were disabled:
  */
-void trace_hardirqs_off_caller(unsigned long ip)
+__visible void trace_hardirqs_off_caller(unsigned long ip)
 {
 	struct task_struct *curr = current;
 
@@ -3055,9 +3055,6 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 	int class_idx;
 	u64 chain_key;
 
-	if (!prove_locking)
-		check = 1;
-
 	if (unlikely(!debug_locks))
 		return 0;
 
@@ -3069,8 +3066,8 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 	if (DEBUG_LOCKS_WARN_ON(!irqs_disabled()))
 		return 0;
 
-	if (lock->key == &__lockdep_no_validate__)
-		check = 1;
+	if (!prove_locking || lock->key == &__lockdep_no_validate__)
+		check = 0;
 
 	if (subclass < NR_LOCKDEP_CACHING_CLASSES)
 		class = lock->class_cache[subclass];
@@ -3138,7 +3135,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 	hlock->holdtime_stamp = lockstat_clock();
 #endif
 
-	if (check == 2 && !mark_irqflags(curr, hlock))
+	if (check && !mark_irqflags(curr, hlock))
 		return 0;
 
 	/* mark it as used: */
@@ -4191,7 +4188,7 @@ void debug_show_held_locks(struct task_struct *task)
 }
 EXPORT_SYMBOL_GPL(debug_show_held_locks);
 
-void lockdep_sys_exit(void)
+asmlinkage __visible void lockdep_sys_exit(void)
 {
 	struct task_struct *curr = current;
 
diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c
new file mode 100644
index 000000000000..f26b1a18e34e
--- /dev/null
+++ b/kernel/locking/locktorture.c
@@ -0,0 +1,452 @@
+/*
+ * Module-based torture test facility for locking
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
+ *
+ * Copyright (C) IBM Corporation, 2014
+ *
+ * Author: Paul E. McKenney <paulmck@us.ibm.com>
+ *	Based on kernel/rcu/torture.c.
+ */
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kthread.h>
+#include <linux/err.h>
+#include <linux/spinlock.h>
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/atomic.h>
+#include <linux/bitops.h>
+#include <linux/completion.h>
+#include <linux/moduleparam.h>
+#include <linux/percpu.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/freezer.h>
+#include <linux/cpu.h>
+#include <linux/delay.h>
+#include <linux/stat.h>
+#include <linux/slab.h>
+#include <linux/trace_clock.h>
+#include <asm/byteorder.h>
+#include <linux/torture.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com>");
+
+torture_param(int, nwriters_stress, -1,
+	     "Number of write-locking stress-test threads");
+torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)");
+torture_param(int, onoff_interval, 0,
+	     "Time between CPU hotplugs (s), 0=disable");
+torture_param(int, shuffle_interval, 3,
+	     "Number of jiffies between shuffles, 0=disable");
+torture_param(int, shutdown_secs, 0, "Shutdown time (j), <= zero to disable.");
+torture_param(int, stat_interval, 60,
+	     "Number of seconds between stats printk()s");
+torture_param(int, stutter, 5, "Number of jiffies to run/halt test, 0=disable");
+torture_param(bool, verbose, true,
+	     "Enable verbose debugging printk()s");
+
+static char *torture_type = "spin_lock";
+module_param(torture_type, charp, 0444);
+MODULE_PARM_DESC(torture_type,
+		 "Type of lock to torture (spin_lock, spin_lock_irq, ...)");
+
+static atomic_t n_lock_torture_errors;
+
+static struct task_struct *stats_task;
+static struct task_struct **writer_tasks;
+
+static int nrealwriters_stress;
+static bool lock_is_write_held;
+
+struct lock_writer_stress_stats {
+	long n_write_lock_fail;
+	long n_write_lock_acquired;
+};
+static struct lock_writer_stress_stats *lwsa;
+
+#if defined(MODULE) || defined(CONFIG_LOCK_TORTURE_TEST_RUNNABLE)
+#define LOCKTORTURE_RUNNABLE_INIT 1
+#else
+#define LOCKTORTURE_RUNNABLE_INIT 0
+#endif
+int locktorture_runnable = LOCKTORTURE_RUNNABLE_INIT;
+module_param(locktorture_runnable, int, 0444);
+MODULE_PARM_DESC(locktorture_runnable, "Start locktorture at boot");
+
+/* Forward reference. */
+static void lock_torture_cleanup(void);
+
+/*
+ * Operations vector for selecting different types of tests.
+ */
+struct lock_torture_ops {
+	void (*init)(void);
+	int (*writelock)(void);
+	void (*write_delay)(struct torture_random_state *trsp);
+	void (*writeunlock)(void);
+	unsigned long flags;
+	const char *name;
+};
+
+static struct lock_torture_ops *cur_ops;
+
+/*
+ * Definitions for lock torture testing.
+ */
+
+static int torture_lock_busted_write_lock(void)
+{
+	return 0;  /* BUGGY, do not use in real life!!! */
+}
+
+static void torture_lock_busted_write_delay(struct torture_random_state *trsp)
+{
+	const unsigned long longdelay_us = 100;
+
+	/* We want a long delay occasionally to force massive contention.  */
+	if (!(torture_random(trsp) %
+	      (nrealwriters_stress * 2000 * longdelay_us)))
+		mdelay(longdelay_us);
+#ifdef CONFIG_PREEMPT
+	if (!(torture_random(trsp) % (nrealwriters_stress * 20000)))
+		preempt_schedule();  /* Allow test to be preempted. */
+#endif
+}
+
+static void torture_lock_busted_write_unlock(void)
+{
+	  /* BUGGY, do not use in real life!!! */
+}
+
+static struct lock_torture_ops lock_busted_ops = {
+	.writelock	= torture_lock_busted_write_lock,
+	.write_delay	= torture_lock_busted_write_delay,
+	.writeunlock	= torture_lock_busted_write_unlock,
+	.name		= "lock_busted"
+};
+
+static DEFINE_SPINLOCK(torture_spinlock);
+
+static int torture_spin_lock_write_lock(void) __acquires(torture_spinlock)
+{
+	spin_lock(&torture_spinlock);
+	return 0;
+}
+
+static void torture_spin_lock_write_delay(struct torture_random_state *trsp)
+{
+	const unsigned long shortdelay_us = 2;
+	const unsigned long longdelay_us = 100;
+
+	/* We want a short delay mostly to emulate likely code, and
+	 * we want a long delay occasionally to force massive contention.
+	 */
+	if (!(torture_random(trsp) %
+	      (nrealwriters_stress * 2000 * longdelay_us)))
+		mdelay(longdelay_us);
+	if (!(torture_random(trsp) %
+	      (nrealwriters_stress * 2 * shortdelay_us)))
+		udelay(shortdelay_us);
+#ifdef CONFIG_PREEMPT
+	if (!(torture_random(trsp) % (nrealwriters_stress * 20000)))
+		preempt_schedule();  /* Allow test to be preempted. */
+#endif
+}
+
+static void torture_spin_lock_write_unlock(void) __releases(torture_spinlock)
+{
+	spin_unlock(&torture_spinlock);
+}
+
+static struct lock_torture_ops spin_lock_ops = {
+	.writelock	= torture_spin_lock_write_lock,
+	.write_delay	= torture_spin_lock_write_delay,
+	.writeunlock	= torture_spin_lock_write_unlock,
+	.name		= "spin_lock"
+};
+
+static int torture_spin_lock_write_lock_irq(void)
+__acquires(torture_spinlock_irq)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&torture_spinlock, flags);
+	cur_ops->flags = flags;
+	return 0;
+}
+
+static void torture_lock_spin_write_unlock_irq(void)
+__releases(torture_spinlock)
+{
+	spin_unlock_irqrestore(&torture_spinlock, cur_ops->flags);
+}
+
+static struct lock_torture_ops spin_lock_irq_ops = {
+	.writelock	= torture_spin_lock_write_lock_irq,
+	.write_delay	= torture_spin_lock_write_delay,
+	.writeunlock	= torture_lock_spin_write_unlock_irq,
+	.name		= "spin_lock_irq"
+};
+
+/*
+ * Lock torture writer kthread.  Repeatedly acquires and releases
+ * the lock, checking for duplicate acquisitions.
+ */
+static int lock_torture_writer(void *arg)
+{
+	struct lock_writer_stress_stats *lwsp = arg;
+	static DEFINE_TORTURE_RANDOM(rand);
+
+	VERBOSE_TOROUT_STRING("lock_torture_writer task started");
+	set_user_nice(current, 19);
+
+	do {
+		schedule_timeout_uninterruptible(1);
+		cur_ops->writelock();
+		if (WARN_ON_ONCE(lock_is_write_held))
+			lwsp->n_write_lock_fail++;
+		lock_is_write_held = 1;
+		lwsp->n_write_lock_acquired++;
+		cur_ops->write_delay(&rand);
+		lock_is_write_held = 0;
+		cur_ops->writeunlock();
+		stutter_wait("lock_torture_writer");
+	} while (!torture_must_stop());
+	torture_kthread_stopping("lock_torture_writer");
+	return 0;
+}
+
+/*
+ * Create an lock-torture-statistics message in the specified buffer.
+ */
+static void lock_torture_printk(char *page)
+{
+	bool fail = 0;
+	int i;
+	long max = 0;
+	long min = lwsa[0].n_write_lock_acquired;
+	long long sum = 0;
+
+	for (i = 0; i < nrealwriters_stress; i++) {
+		if (lwsa[i].n_write_lock_fail)
+			fail = true;
+		sum += lwsa[i].n_write_lock_acquired;
+		if (max < lwsa[i].n_write_lock_fail)
+			max = lwsa[i].n_write_lock_fail;
+		if (min > lwsa[i].n_write_lock_fail)
+			min = lwsa[i].n_write_lock_fail;
+	}
+	page += sprintf(page, "%s%s ", torture_type, TORTURE_FLAG);
+	page += sprintf(page,
+			"Writes:  Total: %lld  Max/Min: %ld/%ld %s  Fail: %d %s\n",
+			sum, max, min, max / 2 > min ? "???" : "",
+			fail, fail ? "!!!" : "");
+	if (fail)
+		atomic_inc(&n_lock_torture_errors);
+}
+
+/*
+ * Print torture statistics.  Caller must ensure that there is only one
+ * call to this function at a given time!!!  This is normally accomplished
+ * by relying on the module system to only have one copy of the module
+ * loaded, and then by giving the lock_torture_stats kthread full control
+ * (or the init/cleanup functions when lock_torture_stats thread is not
+ * running).
+ */
+static void lock_torture_stats_print(void)
+{
+	int size = nrealwriters_stress * 200 + 8192;
+	char *buf;
+
+	buf = kmalloc(size, GFP_KERNEL);
+	if (!buf) {
+		pr_err("lock_torture_stats_print: Out of memory, need: %d",
+		       size);
+		return;
+	}
+	lock_torture_printk(buf);
+	pr_alert("%s", buf);
+	kfree(buf);
+}
+
+/*
+ * Periodically prints torture statistics, if periodic statistics printing
+ * was specified via the stat_interval module parameter.
+ *
+ * No need to worry about fullstop here, since this one doesn't reference
+ * volatile state or register callbacks.
+ */
+static int lock_torture_stats(void *arg)
+{
+	VERBOSE_TOROUT_STRING("lock_torture_stats task started");
+	do {
+		schedule_timeout_interruptible(stat_interval * HZ);
+		lock_torture_stats_print();
+		torture_shutdown_absorb("lock_torture_stats");
+	} while (!torture_must_stop());
+	torture_kthread_stopping("lock_torture_stats");
+	return 0;
+}
+
+static inline void
+lock_torture_print_module_parms(struct lock_torture_ops *cur_ops,
+				const char *tag)
+{
+	pr_alert("%s" TORTURE_FLAG
+		 "--- %s: nwriters_stress=%d stat_interval=%d verbose=%d shuffle_interval=%d stutter=%d shutdown_secs=%d onoff_interval=%d onoff_holdoff=%d\n",
+		 torture_type, tag, nrealwriters_stress, stat_interval, verbose,
+		 shuffle_interval, stutter, shutdown_secs,
+		 onoff_interval, onoff_holdoff);
+}
+
+static void lock_torture_cleanup(void)
+{
+	int i;
+
+	if (torture_cleanup())
+		return;
+
+	if (writer_tasks) {
+		for (i = 0; i < nrealwriters_stress; i++)
+			torture_stop_kthread(lock_torture_writer,
+					     writer_tasks[i]);
+		kfree(writer_tasks);
+		writer_tasks = NULL;
+	}
+
+	torture_stop_kthread(lock_torture_stats, stats_task);
+	lock_torture_stats_print();  /* -After- the stats thread is stopped! */
+
+	if (atomic_read(&n_lock_torture_errors))
+		lock_torture_print_module_parms(cur_ops,
+						"End of test: FAILURE");
+	else if (torture_onoff_failures())
+		lock_torture_print_module_parms(cur_ops,
+						"End of test: LOCK_HOTPLUG");
+	else
+		lock_torture_print_module_parms(cur_ops,
+						"End of test: SUCCESS");
+}
+
+static int __init lock_torture_init(void)
+{
+	int i;
+	int firsterr = 0;
+	static struct lock_torture_ops *torture_ops[] = {
+		&lock_busted_ops, &spin_lock_ops, &spin_lock_irq_ops,
+	};
+
+	torture_init_begin(torture_type, verbose, &locktorture_runnable);
+
+	/* Process args and tell the world that the torturer is on the job. */
+	for (i = 0; i < ARRAY_SIZE(torture_ops); i++) {
+		cur_ops = torture_ops[i];
+		if (strcmp(torture_type, cur_ops->name) == 0)
+			break;
+	}
+	if (i == ARRAY_SIZE(torture_ops)) {
+		pr_alert("lock-torture: invalid torture type: \"%s\"\n",
+			 torture_type);
+		pr_alert("lock-torture types:");
+		for (i = 0; i < ARRAY_SIZE(torture_ops); i++)
+			pr_alert(" %s", torture_ops[i]->name);
+		pr_alert("\n");
+		torture_init_end();
+		return -EINVAL;
+	}
+	if (cur_ops->init)
+		cur_ops->init(); /* no "goto unwind" prior to this point!!! */
+
+	if (nwriters_stress >= 0)
+		nrealwriters_stress = nwriters_stress;
+	else
+		nrealwriters_stress = 2 * num_online_cpus();
+	lock_torture_print_module_parms(cur_ops, "Start of test");
+
+	/* Initialize the statistics so that each run gets its own numbers. */
+
+	lock_is_write_held = 0;
+	lwsa = kmalloc(sizeof(*lwsa) * nrealwriters_stress, GFP_KERNEL);
+	if (lwsa == NULL) {
+		VERBOSE_TOROUT_STRING("lwsa: Out of memory");
+		firsterr = -ENOMEM;
+		goto unwind;
+	}
+	for (i = 0; i < nrealwriters_stress; i++) {
+		lwsa[i].n_write_lock_fail = 0;
+		lwsa[i].n_write_lock_acquired = 0;
+	}
+
+	/* Start up the kthreads. */
+
+	if (onoff_interval > 0) {
+		firsterr = torture_onoff_init(onoff_holdoff * HZ,
+					      onoff_interval * HZ);
+		if (firsterr)
+			goto unwind;
+	}
+	if (shuffle_interval > 0) {
+		firsterr = torture_shuffle_init(shuffle_interval);
+		if (firsterr)
+			goto unwind;
+	}
+	if (shutdown_secs > 0) {
+		firsterr = torture_shutdown_init(shutdown_secs,
+						 lock_torture_cleanup);
+		if (firsterr)
+			goto unwind;
+	}
+	if (stutter > 0) {
+		firsterr = torture_stutter_init(stutter);
+		if (firsterr)
+			goto unwind;
+	}
+
+	writer_tasks = kzalloc(nrealwriters_stress * sizeof(writer_tasks[0]),
+			       GFP_KERNEL);
+	if (writer_tasks == NULL) {
+		VERBOSE_TOROUT_ERRSTRING("writer_tasks: Out of memory");
+		firsterr = -ENOMEM;
+		goto unwind;
+	}
+	for (i = 0; i < nrealwriters_stress; i++) {
+		firsterr = torture_create_kthread(lock_torture_writer, &lwsa[i],
+						  writer_tasks[i]);
+		if (firsterr)
+			goto unwind;
+	}
+	if (stat_interval > 0) {
+		firsterr = torture_create_kthread(lock_torture_stats, NULL,
+						  stats_task);
+		if (firsterr)
+			goto unwind;
+	}
+	torture_init_end();
+	return 0;
+
+unwind:
+	torture_init_end();
+	lock_torture_cleanup();
+	return firsterr;
+}
+
+module_init(lock_torture_init);
+module_exit(lock_torture_cleanup);
diff --git a/kernel/locking/mcs_spinlock.c b/kernel/locking/mcs_spinlock.c
new file mode 100644
index 000000000000..838dc9e00669
--- /dev/null
+++ b/kernel/locking/mcs_spinlock.c
@@ -0,0 +1,178 @@
+
+#include <linux/percpu.h>
+#include <linux/mutex.h>
+#include <linux/sched.h>
+#include "mcs_spinlock.h"
+
+#ifdef CONFIG_SMP
+
+/*
+ * An MCS like lock especially tailored for optimistic spinning for sleeping
+ * lock implementations (mutex, rwsem, etc).
+ *
+ * Using a single mcs node per CPU is safe because sleeping locks should not be
+ * called from interrupt context and we have preemption disabled while
+ * spinning.
+ */
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct optimistic_spin_queue, osq_node);
+
+/*
+ * Get a stable @node->next pointer, either for unlock() or unqueue() purposes.
+ * Can return NULL in case we were the last queued and we updated @lock instead.
+ */
+static inline struct optimistic_spin_queue *
+osq_wait_next(struct optimistic_spin_queue **lock,
+	      struct optimistic_spin_queue *node,
+	      struct optimistic_spin_queue *prev)
+{
+	struct optimistic_spin_queue *next = NULL;
+
+	for (;;) {
+		if (*lock == node && cmpxchg(lock, node, prev) == node) {
+			/*
+			 * We were the last queued, we moved @lock back. @prev
+			 * will now observe @lock and will complete its
+			 * unlock()/unqueue().
+			 */
+			break;
+		}
+
+		/*
+		 * We must xchg() the @node->next value, because if we were to
+		 * leave it in, a concurrent unlock()/unqueue() from
+		 * @node->next might complete Step-A and think its @prev is
+		 * still valid.
+		 *
+		 * If the concurrent unlock()/unqueue() wins the race, we'll
+		 * wait for either @lock to point to us, through its Step-B, or
+		 * wait for a new @node->next from its Step-C.
+		 */
+		if (node->next) {
+			next = xchg(&node->next, NULL);
+			if (next)
+				break;
+		}
+
+		arch_mutex_cpu_relax();
+	}
+
+	return next;
+}
+
+bool osq_lock(struct optimistic_spin_queue **lock)
+{
+	struct optimistic_spin_queue *node = this_cpu_ptr(&osq_node);
+	struct optimistic_spin_queue *prev, *next;
+
+	node->locked = 0;
+	node->next = NULL;
+
+	node->prev = prev = xchg(lock, node);
+	if (likely(prev == NULL))
+		return true;
+
+	ACCESS_ONCE(prev->next) = node;
+
+	/*
+	 * Normally @prev is untouchable after the above store; because at that
+	 * moment unlock can proceed and wipe the node element from stack.
+	 *
+	 * However, since our nodes are static per-cpu storage, we're
+	 * guaranteed their existence -- this allows us to apply
+	 * cmpxchg in an attempt to undo our queueing.
+	 */
+
+	while (!smp_load_acquire(&node->locked)) {
+		/*
+		 * If we need to reschedule bail... so we can block.
+		 */
+		if (need_resched())
+			goto unqueue;
+
+		arch_mutex_cpu_relax();
+	}
+	return true;
+
+unqueue:
+	/*
+	 * Step - A  -- stabilize @prev
+	 *
+	 * Undo our @prev->next assignment; this will make @prev's
+	 * unlock()/unqueue() wait for a next pointer since @lock points to us
+	 * (or later).
+	 */
+
+	for (;;) {
+		if (prev->next == node &&
+		    cmpxchg(&prev->next, node, NULL) == node)
+			break;
+
+		/*
+		 * We can only fail the cmpxchg() racing against an unlock(),
+		 * in which case we should observe @node->locked becomming
+		 * true.
+		 */
+		if (smp_load_acquire(&node->locked))
+			return true;
+
+		arch_mutex_cpu_relax();
+
+		/*
+		 * Or we race against a concurrent unqueue()'s step-B, in which
+		 * case its step-C will write us a new @node->prev pointer.
+		 */
+		prev = ACCESS_ONCE(node->prev);
+	}
+
+	/*
+	 * Step - B -- stabilize @next
+	 *
+	 * Similar to unlock(), wait for @node->next or move @lock from @node
+	 * back to @prev.
+	 */
+
+	next = osq_wait_next(lock, node, prev);
+	if (!next)
+		return false;
+
+	/*
+	 * Step - C -- unlink
+	 *
+	 * @prev is stable because its still waiting for a new @prev->next
+	 * pointer, @next is stable because our @node->next pointer is NULL and
+	 * it will wait in Step-A.
+	 */
+
+	ACCESS_ONCE(next->prev) = prev;
+	ACCESS_ONCE(prev->next) = next;
+
+	return false;
+}
+
+void osq_unlock(struct optimistic_spin_queue **lock)
+{
+	struct optimistic_spin_queue *node = this_cpu_ptr(&osq_node);
+	struct optimistic_spin_queue *next;
+
+	/*
+	 * Fast path for the uncontended case.
+	 */
+	if (likely(cmpxchg(lock, node, NULL) == node))
+		return;
+
+	/*
+	 * Second most likely case.
+	 */
+	next = xchg(&node->next, NULL);
+	if (next) {
+		ACCESS_ONCE(next->locked) = 1;
+		return;
+	}
+
+	next = osq_wait_next(lock, node, NULL);
+	if (next)
+		ACCESS_ONCE(next->locked) = 1;
+}
+
+#endif
+
diff --git a/kernel/locking/mcs_spinlock.h b/kernel/locking/mcs_spinlock.h
new file mode 100644
index 000000000000..a2dbac4aca6b
--- /dev/null
+++ b/kernel/locking/mcs_spinlock.h
@@ -0,0 +1,129 @@
+/*
+ * MCS lock defines
+ *
+ * This file contains the main data structure and API definitions of MCS lock.
+ *
+ * The MCS lock (proposed by Mellor-Crummey and Scott) is a simple spin-lock
+ * with the desirable properties of being fair, and with each cpu trying
+ * to acquire the lock spinning on a local variable.
+ * It avoids expensive cache bouncings that common test-and-set spin-lock
+ * implementations incur.
+ */
+#ifndef __LINUX_MCS_SPINLOCK_H
+#define __LINUX_MCS_SPINLOCK_H
+
+#include <asm/mcs_spinlock.h>
+
+struct mcs_spinlock {
+	struct mcs_spinlock *next;
+	int locked; /* 1 if lock acquired */
+};
+
+#ifndef arch_mcs_spin_lock_contended
+/*
+ * Using smp_load_acquire() provides a memory barrier that ensures
+ * subsequent operations happen after the lock is acquired.
+ */
+#define arch_mcs_spin_lock_contended(l)					\
+do {									\
+	while (!(smp_load_acquire(l)))					\
+		arch_mutex_cpu_relax();					\
+} while (0)
+#endif
+
+#ifndef arch_mcs_spin_unlock_contended
+/*
+ * smp_store_release() provides a memory barrier to ensure all
+ * operations in the critical section has been completed before
+ * unlocking.
+ */
+#define arch_mcs_spin_unlock_contended(l)				\
+	smp_store_release((l), 1)
+#endif
+
+/*
+ * Note: the smp_load_acquire/smp_store_release pair is not
+ * sufficient to form a full memory barrier across
+ * cpus for many architectures (except x86) for mcs_unlock and mcs_lock.
+ * For applications that need a full barrier across multiple cpus
+ * with mcs_unlock and mcs_lock pair, smp_mb__after_unlock_lock() should be
+ * used after mcs_lock.
+ */
+
+/*
+ * In order to acquire the lock, the caller should declare a local node and
+ * pass a reference of the node to this function in addition to the lock.
+ * If the lock has already been acquired, then this will proceed to spin
+ * on this node->locked until the previous lock holder sets the node->locked
+ * in mcs_spin_unlock().
+ *
+ * We don't inline mcs_spin_lock() so that perf can correctly account for the
+ * time spent in this lock function.
+ */
+static inline
+void mcs_spin_lock(struct mcs_spinlock **lock, struct mcs_spinlock *node)
+{
+	struct mcs_spinlock *prev;
+
+	/* Init node */
+	node->locked = 0;
+	node->next   = NULL;
+
+	prev = xchg(lock, node);
+	if (likely(prev == NULL)) {
+		/*
+		 * Lock acquired, don't need to set node->locked to 1. Threads
+		 * only spin on its own node->locked value for lock acquisition.
+		 * However, since this thread can immediately acquire the lock
+		 * and does not proceed to spin on its own node->locked, this
+		 * value won't be used. If a debug mode is needed to
+		 * audit lock status, then set node->locked value here.
+		 */
+		return;
+	}
+	ACCESS_ONCE(prev->next) = node;
+
+	/* Wait until the lock holder passes the lock down. */
+	arch_mcs_spin_lock_contended(&node->locked);
+}
+
+/*
+ * Releases the lock. The caller should pass in the corresponding node that
+ * was used to acquire the lock.
+ */
+static inline
+void mcs_spin_unlock(struct mcs_spinlock **lock, struct mcs_spinlock *node)
+{
+	struct mcs_spinlock *next = ACCESS_ONCE(node->next);
+
+	if (likely(!next)) {
+		/*
+		 * Release the lock by setting it to NULL
+		 */
+		if (likely(cmpxchg(lock, node, NULL) == node))
+			return;
+		/* Wait until the next pointer is set */
+		while (!(next = ACCESS_ONCE(node->next)))
+			arch_mutex_cpu_relax();
+	}
+
+	/* Pass lock to next waiter. */
+	arch_mcs_spin_unlock_contended(&next->locked);
+}
+
+/*
+ * Cancellable version of the MCS lock above.
+ *
+ * Intended for adaptive spinning of sleeping locks:
+ * mutex_lock()/rwsem_down_{read,write}() etc.
+ */
+
+struct optimistic_spin_queue {
+	struct optimistic_spin_queue *next, *prev;
+	int locked; /* 1 if lock acquired */
+};
+
+extern bool osq_lock(struct optimistic_spin_queue **lock);
+extern void osq_unlock(struct optimistic_spin_queue **lock);
+
+#endif /* __LINUX_MCS_SPINLOCK_H */
diff --git a/kernel/locking/mutex-debug.c b/kernel/locking/mutex-debug.c
index faf6f5b53e77..5cf6731b98e9 100644
--- a/kernel/locking/mutex-debug.c
+++ b/kernel/locking/mutex-debug.c
@@ -71,18 +71,23 @@ void mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter,
 
 void debug_mutex_unlock(struct mutex *lock)
 {
-	if (unlikely(!debug_locks))
-		return;
+	if (likely(debug_locks)) {
+		DEBUG_LOCKS_WARN_ON(lock->magic != lock);
 
-	DEBUG_LOCKS_WARN_ON(lock->magic != lock);
+		if (!lock->owner)
+			DEBUG_LOCKS_WARN_ON(!lock->owner);
+		else
+			DEBUG_LOCKS_WARN_ON(lock->owner != current);
 
-	if (!lock->owner)
-		DEBUG_LOCKS_WARN_ON(!lock->owner);
-	else
-		DEBUG_LOCKS_WARN_ON(lock->owner != current);
+		DEBUG_LOCKS_WARN_ON(!lock->wait_list.prev && !lock->wait_list.next);
+		mutex_clear_owner(lock);
+	}
 
-	DEBUG_LOCKS_WARN_ON(!lock->wait_list.prev && !lock->wait_list.next);
-	mutex_clear_owner(lock);
+	/*
+	 * __mutex_slowpath_needs_to_unlock() is explicitly 0 for debug
+	 * mutexes so that we can do it here after we've verified state.
+	 */
+	atomic_set(&lock->count, 1);
 }
 
 void debug_mutex_init(struct mutex *lock, const char *name,
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index 4dd6e4c219de..bc73d33c6760 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -25,6 +25,7 @@
 #include <linux/spinlock.h>
 #include <linux/interrupt.h>
 #include <linux/debug_locks.h>
+#include "mcs_spinlock.h"
 
 /*
  * In the DEBUG case we are using the "NULL fastpath" for mutexes,
@@ -33,6 +34,13 @@
 #ifdef CONFIG_DEBUG_MUTEXES
 # include "mutex-debug.h"
 # include <asm-generic/mutex-null.h>
+/*
+ * Must be 0 for the debug case so we do not do the unlock outside of the
+ * wait_lock region. debug_mutex_unlock() will do the actual unlock in this
+ * case.
+ */
+# undef __mutex_slowpath_needs_to_unlock
+# define  __mutex_slowpath_needs_to_unlock()	0
 #else
 # include "mutex.h"
 # include <asm/mutex.h>
@@ -52,7 +60,7 @@ __mutex_init(struct mutex *lock, const char *name, struct lock_class_key *key)
 	INIT_LIST_HEAD(&lock->wait_list);
 	mutex_clear_owner(lock);
 #ifdef CONFIG_MUTEX_SPIN_ON_OWNER
-	lock->spin_mlock = NULL;
+	lock->osq = NULL;
 #endif
 
 	debug_mutex_init(lock, name, key);
@@ -67,8 +75,7 @@ EXPORT_SYMBOL(__mutex_init);
  * We also put the fastpath first in the kernel image, to make sure the
  * branch is predicted by the CPU as default-untaken.
  */
-static __used noinline void __sched
-__mutex_lock_slowpath(atomic_t *lock_count);
+__visible void __sched __mutex_lock_slowpath(atomic_t *lock_count);
 
 /**
  * mutex_lock - acquire the mutex
@@ -111,54 +118,7 @@ EXPORT_SYMBOL(mutex_lock);
  * more or less simultaneously, the spinners need to acquire a MCS lock
  * first before spinning on the owner field.
  *
- * We don't inline mspin_lock() so that perf can correctly account for the
- * time spent in this lock function.
  */
-struct mspin_node {
-	struct mspin_node *next ;
-	int		  locked;	/* 1 if lock acquired */
-};
-#define	MLOCK(mutex)	((struct mspin_node **)&((mutex)->spin_mlock))
-
-static noinline
-void mspin_lock(struct mspin_node **lock, struct mspin_node *node)
-{
-	struct mspin_node *prev;
-
-	/* Init node */
-	node->locked = 0;
-	node->next   = NULL;
-
-	prev = xchg(lock, node);
-	if (likely(prev == NULL)) {
-		/* Lock acquired */
-		node->locked = 1;
-		return;
-	}
-	ACCESS_ONCE(prev->next) = node;
-	smp_wmb();
-	/* Wait until the lock holder passes the lock down */
-	while (!ACCESS_ONCE(node->locked))
-		arch_mutex_cpu_relax();
-}
-
-static void mspin_unlock(struct mspin_node **lock, struct mspin_node *node)
-{
-	struct mspin_node *next = ACCESS_ONCE(node->next);
-
-	if (likely(!next)) {
-		/*
-		 * Release the lock by setting it to NULL
-		 */
-		if (cmpxchg(lock, node, NULL) == node)
-			return;
-		/* Wait until the next pointer is set */
-		while (!(next = ACCESS_ONCE(node->next)))
-			arch_mutex_cpu_relax();
-	}
-	ACCESS_ONCE(next->locked) = 1;
-	smp_wmb();
-}
 
 /*
  * Mutex spinning code migrated from kernel/sched/core.c
@@ -212,6 +172,9 @@ static inline int mutex_can_spin_on_owner(struct mutex *lock)
 	struct task_struct *owner;
 	int retval = 1;
 
+	if (need_resched())
+		return 0;
+
 	rcu_read_lock();
 	owner = ACCESS_ONCE(lock->owner);
 	if (owner)
@@ -225,7 +188,8 @@ static inline int mutex_can_spin_on_owner(struct mutex *lock)
 }
 #endif
 
-static __used noinline void __sched __mutex_unlock_slowpath(atomic_t *lock_count);
+__visible __used noinline
+void __sched __mutex_unlock_slowpath(atomic_t *lock_count);
 
 /**
  * mutex_unlock - release the mutex
@@ -446,9 +410,11 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 	if (!mutex_can_spin_on_owner(lock))
 		goto slowpath;
 
+	if (!osq_lock(&lock->osq))
+		goto slowpath;
+
 	for (;;) {
 		struct task_struct *owner;
-		struct mspin_node  node;
 
 		if (use_ww_ctx && ww_ctx->acquired > 0) {
 			struct ww_mutex *ww;
@@ -463,19 +429,16 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 			 * performed the optimistic spinning cannot be done.
 			 */
 			if (ACCESS_ONCE(ww->ctx))
-				goto slowpath;
+				break;
 		}
 
 		/*
 		 * If there's an owner, wait for it to either
 		 * release the lock or go to sleep.
 		 */
-		mspin_lock(MLOCK(lock), &node);
 		owner = ACCESS_ONCE(lock->owner);
-		if (owner && !mutex_spin_on_owner(lock, owner)) {
-			mspin_unlock(MLOCK(lock), &node);
-			goto slowpath;
-		}
+		if (owner && !mutex_spin_on_owner(lock, owner))
+			break;
 
 		if ((atomic_read(&lock->count) == 1) &&
 		    (atomic_cmpxchg(&lock->count, 1, 0) == 1)) {
@@ -488,11 +451,10 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 			}
 
 			mutex_set_owner(lock);
-			mspin_unlock(MLOCK(lock), &node);
+			osq_unlock(&lock->osq);
 			preempt_enable();
 			return 0;
 		}
-		mspin_unlock(MLOCK(lock), &node);
 
 		/*
 		 * When there's no owner, we might have preempted between the
@@ -501,7 +463,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 		 * the owner complete.
 		 */
 		if (!owner && (need_resched() || rt_task(task)))
-			goto slowpath;
+			break;
 
 		/*
 		 * The cpu_relax() call is a compiler barrier which forces
@@ -511,7 +473,15 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
 		 */
 		arch_mutex_cpu_relax();
 	}
+	osq_unlock(&lock->osq);
 slowpath:
+	/*
+	 * If we fell out of the spin path because of need_resched(),
+	 * reschedule now, before we try-lock the mutex. This avoids getting
+	 * scheduled out right after we obtained the mutex.
+	 */
+	if (need_resched())
+		schedule_preempt_disabled();
 #endif
 	spin_lock_mutex(&lock->wait_lock, flags);
 
@@ -717,10 +687,6 @@ __mutex_unlock_common_slowpath(atomic_t *lock_count, int nested)
 	struct mutex *lock = container_of(lock_count, struct mutex, count);
 	unsigned long flags;
 
-	spin_lock_mutex(&lock->wait_lock, flags);
-	mutex_release(&lock->dep_map, nested, _RET_IP_);
-	debug_mutex_unlock(lock);
-
 	/*
 	 * some architectures leave the lock unlocked in the fastpath failure
 	 * case, others need to leave it locked. In the later case we have to
@@ -729,6 +695,10 @@ __mutex_unlock_common_slowpath(atomic_t *lock_count, int nested)
 	if (__mutex_slowpath_needs_to_unlock())
 		atomic_set(&lock->count, 1);
 
+	spin_lock_mutex(&lock->wait_lock, flags);
+	mutex_release(&lock->dep_map, nested, _RET_IP_);
+	debug_mutex_unlock(lock);
+
 	if (!list_empty(&lock->wait_list)) {
 		/* get the first entry from the wait-list: */
 		struct mutex_waiter *waiter =
@@ -746,7 +716,7 @@ __mutex_unlock_common_slowpath(atomic_t *lock_count, int nested)
 /*
  * Release the lock, slowpath:
  */
-static __used noinline void
+__visible void
 __mutex_unlock_slowpath(atomic_t *lock_count)
 {
 	__mutex_unlock_common_slowpath(lock_count, 1);
@@ -803,7 +773,7 @@ int __sched mutex_lock_killable(struct mutex *lock)
 }
 EXPORT_SYMBOL(mutex_lock_killable);
 
-static __used noinline void __sched
+__visible void __sched
 __mutex_lock_slowpath(atomic_t *lock_count)
 {
 	struct mutex *lock = container_of(lock_count, struct mutex, count);
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 2e960a2bab81..a620d4d08ca6 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -213,6 +213,18 @@ struct task_struct *rt_mutex_get_top_task(struct task_struct *task)
 }
 
 /*
+ * Called by sched_setscheduler() to check whether the priority change
+ * is overruled by a possible priority boosting.
+ */
+int rt_mutex_check_prio(struct task_struct *task, int newprio)
+{
+	if (!task_has_pi_waiters(task))
+		return 0;
+
+	return task_top_pi_waiter(task)->task->prio <= newprio;
+}
+
+/*
  * Adjust the priority of a task, after its pi_waiters got modified.
  *
  * This can be both boosting and unboosting. task->pi_lock must be held.
@@ -331,9 +343,16 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
 	 * top_waiter can be NULL, when we are in the deboosting
 	 * mode!
 	 */
-	if (top_waiter && (!task_has_pi_waiters(task) ||
-			   top_waiter != task_top_pi_waiter(task)))
-		goto out_unlock_pi;
+	if (top_waiter) {
+		if (!task_has_pi_waiters(task))
+			goto out_unlock_pi;
+		/*
+		 * If deadlock detection is off, we stop here if we
+		 * are not the top pi waiter of the task.
+		 */
+		if (!detect_deadlock && top_waiter != task_top_pi_waiter(task))
+			goto out_unlock_pi;
+	}
 
 	/*
 	 * When deadlock detection is off then we check, if further
@@ -349,7 +368,12 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
 		goto retry;
 	}
 
-	/* Deadlock detection */
+	/*
+	 * Deadlock detection. If the lock is the same as the original
+	 * lock which caused us to walk the lock chain or if the
+	 * current lock is owned by the task which initiated the chain
+	 * walk, we detected a deadlock.
+	 */
 	if (lock == orig_lock || rt_mutex_owner(lock) == top_task) {
 		debug_rt_mutex_deadlock(deadlock_detect, orig_waiter, lock);
 		raw_spin_unlock(&lock->wait_lock);
@@ -515,6 +539,18 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
 	unsigned long flags;
 	int chain_walk = 0, res;
 
+	/*
+	 * Early deadlock detection. We really don't want the task to
+	 * enqueue on itself just to untangle the mess later. It's not
+	 * only an optimization. We drop the locks, so another waiter
+	 * can come in before the chain walk detects the deadlock. So
+	 * the other will detect the deadlock and return -EDEADLOCK,
+	 * which is wrong, as the other waiter is not in a deadlock
+	 * situation.
+	 */
+	if (detect_deadlock && owner == task)
+		return -EDEADLK;
+
 	raw_spin_lock_irqsave(&task->pi_lock, flags);
 	__rt_mutex_adjust_prio(task);
 	waiter->task = task;
diff --git a/kernel/locking/rwsem-xadd.c b/kernel/locking/rwsem-xadd.c
index 19c5fa95e0b4..1d66e08e897d 100644
--- a/kernel/locking/rwsem-xadd.c
+++ b/kernel/locking/rwsem-xadd.c
@@ -143,6 +143,7 @@ __rwsem_do_wake(struct rw_semaphore *sem, enum rwsem_wake_type wake_type)
 /*
  * wait for the read lock to be granted
  */
+__visible
 struct rw_semaphore __sched *rwsem_down_read_failed(struct rw_semaphore *sem)
 {
 	long count, adjustment = -RWSEM_ACTIVE_READ_BIAS;
@@ -190,6 +191,7 @@ struct rw_semaphore __sched *rwsem_down_read_failed(struct rw_semaphore *sem)
 /*
  * wait until we successfully acquire the write lock
  */
+__visible
 struct rw_semaphore __sched *rwsem_down_write_failed(struct rw_semaphore *sem)
 {
 	long count, adjustment = -RWSEM_ACTIVE_WRITE_BIAS;
@@ -252,6 +254,7 @@ struct rw_semaphore __sched *rwsem_down_write_failed(struct rw_semaphore *sem)
  * handle waking up a waiter on the semaphore
  * - up_read/up_write has decremented the active part of count if we come here
  */
+__visible
 struct rw_semaphore *rwsem_wake(struct rw_semaphore *sem)
 {
 	unsigned long flags;
@@ -272,6 +275,7 @@ struct rw_semaphore *rwsem_wake(struct rw_semaphore *sem)
  * - caller incremented waiting part of count and discovered it still negative
  * - just wake up any readers at the front of the queue
  */
+__visible
 struct rw_semaphore *rwsem_downgrade_wake(struct rw_semaphore *sem)
 {
 	unsigned long flags;
diff --git a/kernel/module.c b/kernel/module.c
index d24fcf29cb64..079c4615607d 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -640,7 +640,7 @@ static int module_unload_init(struct module *mod)
 	INIT_LIST_HEAD(&mod->target_list);
 
 	/* Hold reference count during initialization. */
-	__this_cpu_write(mod->refptr->incs, 1);
+	raw_cpu_write(mod->refptr->incs, 1);
 
 	return 0;
 }
@@ -815,9 +815,6 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
 		return -EFAULT;
 	name[MODULE_NAME_LEN-1] = '\0';
 
-	if (!(flags & O_NONBLOCK))
-		pr_warn("waiting module removal not supported: please upgrade\n");
-
 	if (mutex_lock_interruptible(&module_mutex) != 0)
 		return -EINTR;
 
@@ -1013,9 +1010,11 @@ static size_t module_flags_taint(struct module *mod, char *buf)
 		buf[l++] = 'F';
 	if (mod->taints & (1 << TAINT_CRAP))
 		buf[l++] = 'C';
+	if (mod->taints & (1 << TAINT_UNSIGNED_MODULE))
+		buf[l++] = 'E';
 	/*
 	 * TAINT_FORCED_RMMOD: could be added.
-	 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
+	 * TAINT_CPU_OUT_OF_SPEC, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
 	 * apply to modules.
 	 */
 	return l;
@@ -1948,6 +1947,10 @@ static int simplify_symbols(struct module *mod, const struct load_info *info)
 
 		switch (sym[i].st_shndx) {
 		case SHN_COMMON:
+			/* Ignore common symbols */
+			if (!strncmp(name, "__gnu_lto", 9))
+				break;
+
 			/* We compiled with -fno-common.  These are not
 			   supposed to happen.  */
 			pr_debug("Common symbol: %s\n", name);
@@ -3214,7 +3217,7 @@ static int load_module(struct load_info *info, const char __user *uargs,
 		pr_notice_once("%s: module verification failed: signature "
 			       "and/or  required key missing - tainting "
 			       "kernel\n", mod->name);
-		add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_STILL_OK);
+		add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK);
 	}
 #endif
 
@@ -3265,6 +3268,9 @@ static int load_module(struct load_info *info, const char __user *uargs,
 
 	dynamic_debug_setup(info->debug, info->num_debug);
 
+	/* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
+	ftrace_module_init(mod);
+
 	/* Finally it's fully formed, ready to start executing. */
 	err = complete_formation(mod, info);
 	if (err)
@@ -3809,12 +3815,12 @@ void print_modules(void)
 	list_for_each_entry_rcu(mod, &modules, list) {
 		if (mod->state == MODULE_STATE_UNFORMED)
 			continue;
-		printk(" %s%s", mod->name, module_flags(mod, buf));
+		pr_cont(" %s%s", mod->name, module_flags(mod, buf));
 	}
 	preempt_enable();
 	if (last_unloaded_module[0])
-		printk(" [last unloaded: %s]", last_unloaded_module);
-	printk("\n");
+		pr_cont(" [last unloaded: %s]", last_unloaded_module);
+	pr_cont("\n");
 }
 
 #ifdef CONFIG_MODVERSIONS
diff --git a/kernel/notifier.c b/kernel/notifier.c
index 2d5cc4ccff7f..db4c8b08a50c 100644
--- a/kernel/notifier.c
+++ b/kernel/notifier.c
@@ -309,7 +309,7 @@ int __blocking_notifier_call_chain(struct blocking_notifier_head *nh,
 	 * racy then it does not matter what the result of the test
 	 * is, we re-check the list after having taken the lock anyway:
 	 */
-	if (rcu_dereference_raw(nh->head)) {
+	if (rcu_access_pointer(nh->head)) {
 		down_read(&nh->rwsem);
 		ret = notifier_call_chain(&nh->head, val, v, nr_to_call,
 					nr_calls);
diff --git a/kernel/panic.c b/kernel/panic.c
index 6d6300375090..d02fa9fef46a 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -100,7 +100,7 @@ void panic(const char *fmt, ...)
 	va_start(args, fmt);
 	vsnprintf(buf, sizeof(buf), fmt, args);
 	va_end(args);
-	printk(KERN_EMERG "Kernel panic - not syncing: %s\n",buf);
+	pr_emerg("Kernel panic - not syncing: %s\n", buf);
 #ifdef CONFIG_DEBUG_BUGVERBOSE
 	/*
 	 * Avoid nested stack-dumping if a panic occurs during oops processing
@@ -141,7 +141,7 @@ void panic(const char *fmt, ...)
 		 * Delay timeout seconds before rebooting the machine.
 		 * We can't use the "normal" timers since we just panicked.
 		 */
-		printk(KERN_EMERG "Rebooting in %d seconds..", panic_timeout);
+		pr_emerg("Rebooting in %d seconds..", panic_timeout);
 
 		for (i = 0; i < panic_timeout * 1000; i += PANIC_TIMER_STEP) {
 			touch_nmi_watchdog();
@@ -165,7 +165,7 @@ void panic(const char *fmt, ...)
 		extern int stop_a_enabled;
 		/* Make sure the user can actually press Stop-A (L1-A) */
 		stop_a_enabled = 1;
-		printk(KERN_EMERG "Press Stop-A (L1-A) to return to the boot prom\n");
+		pr_emerg("Press Stop-A (L1-A) to return to the boot prom\n");
 	}
 #endif
 #if defined(CONFIG_S390)
@@ -176,6 +176,7 @@ void panic(const char *fmt, ...)
 		disabled_wait(caller);
 	}
 #endif
+	pr_emerg("---[ end Kernel panic - not syncing: %s\n", buf);
 	local_irq_enable();
 	for (i = 0; ; i += PANIC_TIMER_STEP) {
 		touch_softlockup_watchdog();
@@ -199,7 +200,7 @@ struct tnt {
 static const struct tnt tnts[] = {
 	{ TAINT_PROPRIETARY_MODULE,	'P', 'G' },
 	{ TAINT_FORCED_MODULE,		'F', ' ' },
-	{ TAINT_UNSAFE_SMP,		'S', ' ' },
+	{ TAINT_CPU_OUT_OF_SPEC,	'S', ' ' },
 	{ TAINT_FORCED_RMMOD,		'R', ' ' },
 	{ TAINT_MACHINE_CHECK,		'M', ' ' },
 	{ TAINT_BAD_PAGE,		'B', ' ' },
@@ -210,6 +211,7 @@ static const struct tnt tnts[] = {
 	{ TAINT_CRAP,			'C', ' ' },
 	{ TAINT_FIRMWARE_WORKAROUND,	'I', ' ' },
 	{ TAINT_OOT_MODULE,		'O', ' ' },
+	{ TAINT_UNSIGNED_MODULE,	'E', ' ' },
 };
 
 /**
@@ -228,6 +230,7 @@ static const struct tnt tnts[] = {
  *  'C' - modules from drivers/staging are loaded.
  *  'I' - Working around severe firmware bug.
  *  'O' - Out-of-tree module has been loaded.
+ *  'E' - Unsigned module has been loaded.
  *
  *	The string is overwritten by the next call to print_tainted().
  */
@@ -274,8 +277,7 @@ unsigned long get_taint(void)
 void add_taint(unsigned flag, enum lockdep_ok lockdep_ok)
 {
 	if (lockdep_ok == LOCKDEP_NOW_UNRELIABLE && __debug_locks_off())
-		printk(KERN_WARNING
-		       "Disabling lock debugging due to kernel taint\n");
+		pr_warn("Disabling lock debugging due to kernel taint\n");
 
 	set_bit(flag, &tainted_mask);
 }
@@ -380,8 +382,7 @@ late_initcall(init_oops_id);
 void print_oops_end_marker(void)
 {
 	init_oops_id();
-	printk(KERN_WARNING "---[ end trace %016llx ]---\n",
-		(unsigned long long)oops_id);
+	pr_warn("---[ end trace %016llx ]---\n", (unsigned long long)oops_id);
 }
 
 /*
@@ -459,7 +460,7 @@ EXPORT_SYMBOL(warn_slowpath_null);
  * Called when gcc's -fstack-protector feature is used, and
  * gcc detects corruption of the on-stack canary value
  */
-void __stack_chk_fail(void)
+__visible void __stack_chk_fail(void)
 {
 	panic("stack-protector: Kernel stack is corrupted in: %p\n",
 		__builtin_return_address(0));
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index 06c62de9c711..db95d8eb761b 100644
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -318,7 +318,9 @@ static void *pidns_get(struct task_struct *task)
 	struct pid_namespace *ns;
 
 	rcu_read_lock();
-	ns = get_pid_ns(task_active_pid_ns(task));
+	ns = task_active_pid_ns(task);
+	if (ns)
+		get_pid_ns(ns);
 	rcu_read_unlock();
 
 	return ns;
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 37170d4dd9a6..f4f2073711d3 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -973,16 +973,20 @@ static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
 static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
 			    const char *buf, size_t n)
 {
-	unsigned int maj, min;
 	dev_t res;
-	int ret = -EINVAL;
+	int len = n;
+	char *name;
 
-	if (sscanf(buf, "%u:%u", &maj, &min) != 2)
-		goto out;
+	if (len && buf[len-1] == '\n')
+		len--;
+	name = kstrndup(buf, len, GFP_KERNEL);
+	if (!name)
+		return -ENOMEM;
 
-	res = MKDEV(maj,min);
-	if (maj != MAJOR(res) || min != MINOR(res))
-		goto out;
+	res = name_to_dev_t(name);
+	kfree(name);
+	if (!res)
+		return -EINVAL;
 
 	lock_system_sleep();
 	swsusp_resume_device = res;
@@ -990,9 +994,7 @@ static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
 	printk(KERN_INFO "PM: Starting manual resume from disk\n");
 	noresume = 0;
 	software_resume();
-	ret = n;
- out:
-	return ret;
+	return n;
 }
 
 power_attr(resume);
diff --git a/kernel/power/main.c b/kernel/power/main.c
index 1d1bf630e6e9..6271bc4073ef 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -282,8 +282,8 @@ struct kobject *power_kobj;
  *	state - control system power state.
  *
  *	show() returns what states are supported, which is hard-coded to
- *	'standby' (Power-On Suspend), 'mem' (Suspend-to-RAM), and
- *	'disk' (Suspend-to-Disk).
+ *	'freeze' (Low-Power Idle), 'standby' (Power-On Suspend),
+ *	'mem' (Suspend-to-RAM), and 'disk' (Suspend-to-Disk).
  *
  *	store() accepts one of those strings, translates it into the
  *	proper enumerated value, and initiates a suspend transition.
diff --git a/kernel/power/power.h b/kernel/power/power.h
index 7d4b7ffb3c1d..15f37ea08719 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -2,6 +2,7 @@
 #include <linux/suspend_ioctls.h>
 #include <linux/utsname.h>
 #include <linux/freezer.h>
+#include <linux/compiler.h>
 
 struct swsusp_info {
 	struct new_utsname	uts;
@@ -11,7 +12,7 @@ struct swsusp_info {
 	unsigned long		image_pages;
 	unsigned long		pages;
 	unsigned long		size;
-} __attribute__((aligned(PAGE_SIZE)));
+} __aligned(PAGE_SIZE);
 
 #ifdef CONFIG_HIBERNATION
 /* kernel/power/snapshot.c */
@@ -49,6 +50,8 @@ static inline char *check_image_kernel(struct swsusp_info *info)
  */
 #define SPARE_PAGES	((1024 * 1024) >> PAGE_SHIFT)
 
+asmlinkage int swsusp_save(void);
+
 /* kernel/power/hibernate.c */
 extern bool freezer_test_done;
 
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index 8dff9b48075a..884b77058864 100644
--- a/kernel/power/qos.c
+++ b/kernel/power/qos.c
@@ -66,6 +66,7 @@ static struct pm_qos_constraints cpu_dma_constraints = {
 	.list = PLIST_HEAD_INIT(cpu_dma_constraints.list),
 	.target_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE,
 	.default_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE,
+	.no_constraint_value = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE,
 	.type = PM_QOS_MIN,
 	.notifiers = &cpu_dma_lat_notifier,
 };
@@ -79,6 +80,7 @@ static struct pm_qos_constraints network_lat_constraints = {
 	.list = PLIST_HEAD_INIT(network_lat_constraints.list),
 	.target_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE,
 	.default_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE,
+	.no_constraint_value = PM_QOS_NETWORK_LAT_DEFAULT_VALUE,
 	.type = PM_QOS_MIN,
 	.notifiers = &network_lat_notifier,
 };
@@ -93,6 +95,7 @@ static struct pm_qos_constraints network_tput_constraints = {
 	.list = PLIST_HEAD_INIT(network_tput_constraints.list),
 	.target_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE,
 	.default_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE,
+	.no_constraint_value = PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE,
 	.type = PM_QOS_MAX,
 	.notifiers = &network_throughput_notifier,
 };
@@ -128,7 +131,7 @@ static const struct file_operations pm_qos_power_fops = {
 static inline int pm_qos_get_value(struct pm_qos_constraints *c)
 {
 	if (plist_head_empty(&c->list))
-		return c->default_value;
+		return c->no_constraint_value;
 
 	switch (c->type) {
 	case PM_QOS_MIN:
@@ -170,6 +173,7 @@ int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node,
 {
 	unsigned long flags;
 	int prev_value, curr_value, new_value;
+	int ret;
 
 	spin_lock_irqsave(&pm_qos_lock, flags);
 	prev_value = pm_qos_get_value(c);
@@ -205,13 +209,15 @@ int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node,
 
 	trace_pm_qos_update_target(action, prev_value, curr_value);
 	if (prev_value != curr_value) {
-		blocking_notifier_call_chain(c->notifiers,
-					     (unsigned long)curr_value,
-					     NULL);
-		return 1;
+		ret = 1;
+		if (c->notifiers)
+			blocking_notifier_call_chain(c->notifiers,
+						     (unsigned long)curr_value,
+						     NULL);
 	} else {
-		return 0;
+		ret = 0;
 	}
+	return ret;
 }
 
 /**
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index d9f61a145802..1ea328aafdc9 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -27,6 +27,7 @@
 #include <linux/highmem.h>
 #include <linux/list.h>
 #include <linux/slab.h>
+#include <linux/compiler.h>
 
 #include <asm/uaccess.h>
 #include <asm/mmu_context.h>
@@ -155,7 +156,7 @@ static inline void free_image_page(void *addr, int clear_nosave_free)
 struct linked_page {
 	struct linked_page *next;
 	char data[LINKED_PAGE_DATA_SIZE];
-} __attribute__((packed));
+} __packed;
 
 static inline void
 free_list_of_pages(struct linked_page *list, int clear_page_nosave)
@@ -1268,7 +1269,7 @@ static void free_unnecessary_pages(void)
  * [number of saveable pages] - [number of pages that can be freed in theory]
  *
  * where the second term is the sum of (1) reclaimable slab pages, (2) active
- * and (3) inactive anonymouns pages, (4) active and (5) inactive file pages,
+ * and (3) inactive anonymous pages, (4) active and (5) inactive file pages,
  * minus mapped file pages.
  */
 static unsigned long minimum_image_size(unsigned long saveable)
@@ -1585,7 +1586,7 @@ swsusp_alloc(struct memory_bitmap *orig_bm, struct memory_bitmap *copy_bm,
 	return -ENOMEM;
 }
 
-asmlinkage int swsusp_save(void)
+asmlinkage __visible int swsusp_save(void)
 {
 	unsigned int nr_pages, nr_highmem;
 
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 62ee437b5c7e..8233cd4047d7 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -14,6 +14,7 @@
 #include <linux/init.h>
 #include <linux/console.h>
 #include <linux/cpu.h>
+#include <linux/cpuidle.h>
 #include <linux/syscalls.h>
 #include <linux/gfp.h>
 #include <linux/io.h>
@@ -26,6 +27,7 @@
 #include <linux/syscore_ops.h>
 #include <linux/ftrace.h>
 #include <trace/events/power.h>
+#include <linux/compiler.h>
 
 #include "power.h"
 
@@ -39,7 +41,7 @@ static const struct platform_suspend_ops *suspend_ops;
 
 static bool need_suspend_ops(suspend_state_t state)
 {
-	return !!(state > PM_SUSPEND_FREEZE);
+	return state > PM_SUSPEND_FREEZE;
 }
 
 static DECLARE_WAIT_QUEUE_HEAD(suspend_freeze_wait_head);
@@ -52,7 +54,9 @@ static void freeze_begin(void)
 
 static void freeze_enter(void)
 {
+	cpuidle_resume();
 	wait_event(suspend_freeze_wait_head, suspend_freeze_wake);
+	cpuidle_pause();
 }
 
 void freeze_wake(void)
@@ -156,13 +160,13 @@ static int suspend_prepare(suspend_state_t state)
 }
 
 /* default implementation */
-void __attribute__ ((weak)) arch_suspend_disable_irqs(void)
+void __weak arch_suspend_disable_irqs(void)
 {
 	local_irq_disable();
 }
 
 /* default implementation */
-void __attribute__ ((weak)) arch_suspend_enable_irqs(void)
+void __weak arch_suspend_enable_irqs(void)
 {
 	local_irq_enable();
 }
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 7c33ed200410..8c9a4819f798 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -101,7 +101,7 @@ struct swsusp_header {
 	unsigned int flags;	/* Flags to pass to the "boot" kernel */
 	char	orig_sig[10];
 	char	sig[10];
-} __attribute__((packed));
+} __packed;
 
 static struct swsusp_header *swsusp_header;
 
diff --git a/kernel/power/wakelock.c b/kernel/power/wakelock.c
index 8f50de394d22..019069c84ff6 100644
--- a/kernel/power/wakelock.c
+++ b/kernel/power/wakelock.c
@@ -18,6 +18,8 @@
 #include <linux/rbtree.h>
 #include <linux/slab.h>
 
+#include "power.h"
+
 static DEFINE_MUTEX(wakelocks_lock);
 
 struct wakelock {
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 4dae9cbe9259..7228258b85ec 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -319,7 +319,7 @@ static void log_store(int facility, int level,
 		else
 			free = log_first_idx - log_next_idx;
 
-		if (free > size + sizeof(struct printk_log))
+		if (free >= size + sizeof(struct printk_log))
 			break;
 
 		/* drop old messages until we have enough contiuous space */
@@ -327,7 +327,7 @@ static void log_store(int facility, int level,
 		log_first_seq++;
 	}
 
-	if (log_next_idx + size + sizeof(struct printk_log) >= log_buf_len) {
+	if (log_next_idx + size + sizeof(struct printk_log) > log_buf_len) {
 		/*
 		 * This message + an additional empty header does not fit
 		 * at the end of the buffer. Add an empty header with len == 0
@@ -351,7 +351,7 @@ static void log_store(int facility, int level,
 	else
 		msg->ts_nsec = local_clock();
 	memset(log_dict(msg) + dict_len, 0, pad_len);
-	msg->len = sizeof(struct printk_log) + text_len + dict_len + pad_len;
+	msg->len = size;
 
 	/* insert message */
 	log_next_idx += msg->len;
@@ -1560,9 +1560,12 @@ asmlinkage int vprintk_emit(int facility, int level,
 					level = kern_level - '0';
 			case 'd':	/* KERN_DEFAULT */
 				lflags |= LOG_PREFIX;
-			case 'c':	/* KERN_CONT */
-				break;
 			}
+			/*
+			 * No need to check length here because vscnprintf
+			 * put '\0' at the end of the string. Only valid and
+			 * newly printed level is detected.
+			 */
 			text_len -= end_of_header - text;
 			text = (char *)end_of_header;
 		}
@@ -1671,7 +1674,7 @@ EXPORT_SYMBOL(printk_emit);
  *
  * See the vsnprintf() documentation for format string extensions over C99.
  */
-asmlinkage int printk(const char *fmt, ...)
+asmlinkage __visible int printk(const char *fmt, ...)
 {
 	va_list args;
 	int r;
@@ -1734,7 +1737,7 @@ void early_vprintk(const char *fmt, va_list ap)
 	}
 }
 
-asmlinkage void early_printk(const char *fmt, ...)
+asmlinkage __visible void early_printk(const char *fmt, ...)
 {
 	va_list ap;
 
@@ -1880,6 +1883,7 @@ void suspend_console(void)
 	console_lock();
 	console_suspended = 1;
 	up(&console_sem);
+	mutex_release(&console_lock_dep_map, 1, _RET_IP_);
 }
 
 void resume_console(void)
@@ -1887,6 +1891,7 @@ void resume_console(void)
 	if (!console_suspend_enabled)
 		return;
 	down(&console_sem);
+	mutex_acquire(&console_lock_dep_map, 0, 0, _RET_IP_);
 	console_suspended = 0;
 	console_unlock();
 }
diff --git a/kernel/profile.c b/kernel/profile.c
index ebdd9c1a86b4..cb980f0c731b 100644
--- a/kernel/profile.c
+++ b/kernel/profile.c
@@ -591,18 +591,28 @@ out_cleanup:
 int __ref create_proc_profile(void) /* false positive from hotcpu_notifier */
 {
 	struct proc_dir_entry *entry;
+	int err = 0;
 
 	if (!prof_on)
 		return 0;
-	if (create_hash_tables())
-		return -ENOMEM;
+
+	cpu_notifier_register_begin();
+
+	if (create_hash_tables()) {
+		err = -ENOMEM;
+		goto out;
+	}
+
 	entry = proc_create("profile", S_IWUSR | S_IRUGO,
 			    NULL, &proc_profile_operations);
 	if (!entry)
-		return 0;
+		goto out;
 	proc_set_size(entry, (1 + prof_len) * sizeof(atomic_t));
-	hotcpu_notifier(profile_cpu_callback, 0);
-	return 0;
+	__hotcpu_notifier(profile_cpu_callback, 0);
+
+out:
+	cpu_notifier_register_done();
+	return err;
 }
-module_init(create_proc_profile);
+subsys_initcall(create_proc_profile);
 #endif /* CONFIG_PROC_FS */
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 1f4bcb3cc21c..adf98622cb32 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -1180,8 +1180,8 @@ int compat_ptrace_request(struct task_struct *child, compat_long_t request,
 	return ret;
 }
 
-asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
-				  compat_long_t addr, compat_long_t data)
+COMPAT_SYSCALL_DEFINE4(ptrace, compat_long_t, request, compat_long_t, pid,
+		       compat_long_t, addr, compat_long_t, data)
 {
 	struct task_struct *child;
 	long ret;
diff --git a/kernel/rcu/Makefile b/kernel/rcu/Makefile
index 01e9ec37a3e3..807ccfbf69b3 100644
--- a/kernel/rcu/Makefile
+++ b/kernel/rcu/Makefile
@@ -1,5 +1,5 @@
 obj-y += update.o srcu.o
-obj-$(CONFIG_RCU_TORTURE_TEST) += torture.o
+obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o
 obj-$(CONFIG_TREE_RCU) += tree.o
 obj-$(CONFIG_TREE_PREEMPT_RCU) += tree.o
 obj-$(CONFIG_TREE_RCU_TRACE) += tree_trace.o
diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h
index 79c3877e9c5b..bfda2726ca45 100644
--- a/kernel/rcu/rcu.h
+++ b/kernel/rcu/rcu.h
@@ -12,8 +12,8 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
  *
  * Copyright IBM Corporation, 2011
  *
@@ -23,6 +23,7 @@
 #ifndef __LINUX_RCU_H
 #define __LINUX_RCU_H
 
+#include <trace/events/rcu.h>
 #ifdef CONFIG_RCU_TRACE
 #define RCU_TRACE(stmt) stmt
 #else /* #ifdef CONFIG_RCU_TRACE */
@@ -116,8 +117,6 @@ static inline bool __rcu_reclaim(const char *rn, struct rcu_head *head)
 	}
 }
 
-extern int rcu_expedited;
-
 #ifdef CONFIG_RCU_STALL_COMMON
 
 extern int rcu_cpu_stall_suppress;
diff --git a/kernel/rcu/torture.c b/kernel/rcu/rcutorture.c
index 732f8ae3086a..bd30bc61bc05 100644
--- a/kernel/rcu/torture.c
+++ b/kernel/rcu/rcutorture.c
@@ -12,8 +12,8 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
  *
  * Copyright (C) IBM Corporation, 2005, 2006
  *
@@ -48,110 +48,58 @@
 #include <linux/slab.h>
 #include <linux/trace_clock.h>
 #include <asm/byteorder.h>
+#include <linux/torture.h>
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and Josh Triplett <josh@freedesktop.org>");
 
-MODULE_ALIAS("rcutorture");
-#ifdef MODULE_PARAM_PREFIX
-#undef MODULE_PARAM_PREFIX
-#endif
-#define MODULE_PARAM_PREFIX "rcutorture."
-
-static int fqs_duration;
-module_param(fqs_duration, int, 0444);
-MODULE_PARM_DESC(fqs_duration, "Duration of fqs bursts (us), 0 to disable");
-static int fqs_holdoff;
-module_param(fqs_holdoff, int, 0444);
-MODULE_PARM_DESC(fqs_holdoff, "Holdoff time within fqs bursts (us)");
-static int fqs_stutter = 3;
-module_param(fqs_stutter, int, 0444);
-MODULE_PARM_DESC(fqs_stutter, "Wait time between fqs bursts (s)");
-static bool gp_exp;
-module_param(gp_exp, bool, 0444);
-MODULE_PARM_DESC(gp_exp, "Use expedited GP wait primitives");
-static bool gp_normal;
-module_param(gp_normal, bool, 0444);
-MODULE_PARM_DESC(gp_normal, "Use normal (non-expedited) GP wait primitives");
-static int irqreader = 1;
-module_param(irqreader, int, 0444);
-MODULE_PARM_DESC(irqreader, "Allow RCU readers from irq handlers");
-static int n_barrier_cbs;
-module_param(n_barrier_cbs, int, 0444);
-MODULE_PARM_DESC(n_barrier_cbs, "# of callbacks/kthreads for barrier testing");
-static int nfakewriters = 4;
-module_param(nfakewriters, int, 0444);
-MODULE_PARM_DESC(nfakewriters, "Number of RCU fake writer threads");
-static int nreaders = -1;
-module_param(nreaders, int, 0444);
-MODULE_PARM_DESC(nreaders, "Number of RCU reader threads");
-static int object_debug;
-module_param(object_debug, int, 0444);
-MODULE_PARM_DESC(object_debug, "Enable debug-object double call_rcu() testing");
-static int onoff_holdoff;
-module_param(onoff_holdoff, int, 0444);
-MODULE_PARM_DESC(onoff_holdoff, "Time after boot before CPU hotplugs (s)");
-static int onoff_interval;
-module_param(onoff_interval, int, 0444);
-MODULE_PARM_DESC(onoff_interval, "Time between CPU hotplugs (s), 0=disable");
-static int shuffle_interval = 3;
-module_param(shuffle_interval, int, 0444);
-MODULE_PARM_DESC(shuffle_interval, "Number of seconds between shuffles");
-static int shutdown_secs;
-module_param(shutdown_secs, int, 0444);
-MODULE_PARM_DESC(shutdown_secs, "Shutdown time (s), <= zero to disable.");
-static int stall_cpu;
-module_param(stall_cpu, int, 0444);
-MODULE_PARM_DESC(stall_cpu, "Stall duration (s), zero to disable.");
-static int stall_cpu_holdoff = 10;
-module_param(stall_cpu_holdoff, int, 0444);
-MODULE_PARM_DESC(stall_cpu_holdoff, "Time to wait before starting stall (s).");
-static int stat_interval = 60;
-module_param(stat_interval, int, 0644);
-MODULE_PARM_DESC(stat_interval, "Number of seconds between stats printk()s");
-static int stutter = 5;
-module_param(stutter, int, 0444);
-MODULE_PARM_DESC(stutter, "Number of seconds to run/halt test");
-static int test_boost = 1;
-module_param(test_boost, int, 0444);
-MODULE_PARM_DESC(test_boost, "Test RCU prio boost: 0=no, 1=maybe, 2=yes.");
-static int test_boost_duration = 4;
-module_param(test_boost_duration, int, 0444);
-MODULE_PARM_DESC(test_boost_duration, "Duration of each boost test, seconds.");
-static int test_boost_interval = 7;
-module_param(test_boost_interval, int, 0444);
-MODULE_PARM_DESC(test_boost_interval, "Interval between boost tests, seconds.");
-static bool test_no_idle_hz = true;
-module_param(test_no_idle_hz, bool, 0444);
-MODULE_PARM_DESC(test_no_idle_hz, "Test support for tickless idle CPUs");
+
+torture_param(int, fqs_duration, 0,
+	      "Duration of fqs bursts (us), 0 to disable");
+torture_param(int, fqs_holdoff, 0, "Holdoff time within fqs bursts (us)");
+torture_param(int, fqs_stutter, 3, "Wait time between fqs bursts (s)");
+torture_param(bool, gp_exp, false, "Use expedited GP wait primitives");
+torture_param(bool, gp_normal, false,
+	     "Use normal (non-expedited) GP wait primitives");
+torture_param(int, irqreader, 1, "Allow RCU readers from irq handlers");
+torture_param(int, n_barrier_cbs, 0,
+	     "# of callbacks/kthreads for barrier testing");
+torture_param(int, nfakewriters, 4, "Number of RCU fake writer threads");
+torture_param(int, nreaders, -1, "Number of RCU reader threads");
+torture_param(int, object_debug, 0,
+	     "Enable debug-object double call_rcu() testing");
+torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)");
+torture_param(int, onoff_interval, 0,
+	     "Time between CPU hotplugs (s), 0=disable");
+torture_param(int, shuffle_interval, 3, "Number of seconds between shuffles");
+torture_param(int, shutdown_secs, 0, "Shutdown time (s), <= zero to disable.");
+torture_param(int, stall_cpu, 0, "Stall duration (s), zero to disable.");
+torture_param(int, stall_cpu_holdoff, 10,
+	     "Time to wait before starting stall (s).");
+torture_param(int, stat_interval, 60,
+	     "Number of seconds between stats printk()s");
+torture_param(int, stutter, 5, "Number of seconds to run/halt test");
+torture_param(int, test_boost, 1, "Test RCU prio boost: 0=no, 1=maybe, 2=yes.");
+torture_param(int, test_boost_duration, 4,
+	     "Duration of each boost test, seconds.");
+torture_param(int, test_boost_interval, 7,
+	     "Interval between boost tests, seconds.");
+torture_param(bool, test_no_idle_hz, true,
+	     "Test support for tickless idle CPUs");
+torture_param(bool, verbose, true,
+	     "Enable verbose debugging printk()s");
+
 static char *torture_type = "rcu";
 module_param(torture_type, charp, 0444);
 MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, rcu_bh, ...)");
-static bool verbose;
-module_param(verbose, bool, 0444);
-MODULE_PARM_DESC(verbose, "Enable verbose debugging printk()s");
-
-#define TORTURE_FLAG "-torture:"
-#define PRINTK_STRING(s) \
-	do { pr_alert("%s" TORTURE_FLAG s "\n", torture_type); } while (0)
-#define VERBOSE_PRINTK_STRING(s) \
-	do { if (verbose) pr_alert("%s" TORTURE_FLAG s "\n", torture_type); } while (0)
-#define VERBOSE_PRINTK_ERRSTRING(s) \
-	do { if (verbose) pr_alert("%s" TORTURE_FLAG "!!! " s "\n", torture_type); } while (0)
 
 static int nrealreaders;
 static struct task_struct *writer_task;
 static struct task_struct **fakewriter_tasks;
 static struct task_struct **reader_tasks;
 static struct task_struct *stats_task;
-static struct task_struct *shuffler_task;
-static struct task_struct *stutter_task;
 static struct task_struct *fqs_task;
 static struct task_struct *boost_tasks[NR_CPUS];
-static struct task_struct *shutdown_task;
-#ifdef CONFIG_HOTPLUG_CPU
-static struct task_struct *onoff_task;
-#endif /* #ifdef CONFIG_HOTPLUG_CPU */
 static struct task_struct *stall_task;
 static struct task_struct **barrier_cbs_tasks;
 static struct task_struct *barrier_task;
@@ -170,10 +118,10 @@ static struct rcu_torture __rcu *rcu_torture_current;
 static unsigned long rcu_torture_current_version;
 static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN];
 static DEFINE_SPINLOCK(rcu_torture_lock);
-static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) =
-	{ 0 };
-static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_batch) =
-	{ 0 };
+static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1],
+		      rcu_torture_count) = { 0 };
+static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1],
+		      rcu_torture_batch) = { 0 };
 static atomic_t rcu_torture_wcount[RCU_TORTURE_PIPE_LEN + 1];
 static atomic_t n_rcu_torture_alloc;
 static atomic_t n_rcu_torture_alloc_fail;
@@ -186,22 +134,9 @@ static long n_rcu_torture_boost_rterror;
 static long n_rcu_torture_boost_failure;
 static long n_rcu_torture_boosts;
 static long n_rcu_torture_timers;
-static long n_offline_attempts;
-static long n_offline_successes;
-static unsigned long sum_offline;
-static int min_offline = -1;
-static int max_offline;
-static long n_online_attempts;
-static long n_online_successes;
-static unsigned long sum_online;
-static int min_online = -1;
-static int max_online;
 static long n_barrier_attempts;
 static long n_barrier_successes;
 static struct list_head rcu_torture_removed;
-static cpumask_var_t shuffle_tmp_mask;
-
-static int stutter_pause_test;
 
 #if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE)
 #define RCUTORTURE_RUNNABLE_INIT 1
@@ -232,7 +167,6 @@ static u64 notrace rcu_trace_clock_local(void)
 }
 #endif /* #else #ifdef CONFIG_RCU_TRACE */
 
-static unsigned long shutdown_time;	/* jiffies to system shutdown. */
 static unsigned long boost_starttime;	/* jiffies of next boost test start. */
 DEFINE_MUTEX(boost_mutex);		/* protect setting boost_starttime */
 					/*  and boost task create/destroy. */
@@ -242,51 +176,6 @@ static atomic_t barrier_cbs_invoked;	/* Barrier callbacks invoked. */
 static wait_queue_head_t *barrier_cbs_wq; /* Coordinate barrier testing. */
 static DECLARE_WAIT_QUEUE_HEAD(barrier_wq);
 
-/* Mediate rmmod and system shutdown.  Concurrent rmmod & shutdown illegal! */
-
-#define FULLSTOP_DONTSTOP 0	/* Normal operation. */
-#define FULLSTOP_SHUTDOWN 1	/* System shutdown with rcutorture running. */
-#define FULLSTOP_RMMOD    2	/* Normal rmmod of rcutorture. */
-static int fullstop = FULLSTOP_RMMOD;
-/*
- * Protect fullstop transitions and spawning of kthreads.
- */
-static DEFINE_MUTEX(fullstop_mutex);
-
-/* Forward reference. */
-static void rcu_torture_cleanup(void);
-
-/*
- * Detect and respond to a system shutdown.
- */
-static int
-rcutorture_shutdown_notify(struct notifier_block *unused1,
-			   unsigned long unused2, void *unused3)
-{
-	mutex_lock(&fullstop_mutex);
-	if (fullstop == FULLSTOP_DONTSTOP)
-		fullstop = FULLSTOP_SHUTDOWN;
-	else
-		pr_warn(/* but going down anyway, so... */
-		       "Concurrent 'rmmod rcutorture' and shutdown illegal!\n");
-	mutex_unlock(&fullstop_mutex);
-	return NOTIFY_DONE;
-}
-
-/*
- * Absorb kthreads into a kernel function that won't return, so that
- * they won't ever access module text or data again.
- */
-static void rcutorture_shutdown_absorb(const char *title)
-{
-	if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
-		pr_notice(
-		       "rcutorture thread %s parking due to system shutdown\n",
-		       title);
-		schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT);
-	}
-}
-
 /*
  * Allocate an element from the rcu_tortures pool.
  */
@@ -320,44 +209,6 @@ rcu_torture_free(struct rcu_torture *p)
 	spin_unlock_bh(&rcu_torture_lock);
 }
 
-struct rcu_random_state {
-	unsigned long rrs_state;
-	long rrs_count;
-};
-
-#define RCU_RANDOM_MULT 39916801  /* prime */
-#define RCU_RANDOM_ADD	479001701 /* prime */
-#define RCU_RANDOM_REFRESH 10000
-
-#define DEFINE_RCU_RANDOM(name) struct rcu_random_state name = { 0, 0 }
-
-/*
- * Crude but fast random-number generator.  Uses a linear congruential
- * generator, with occasional help from cpu_clock().
- */
-static unsigned long
-rcu_random(struct rcu_random_state *rrsp)
-{
-	if (--rrsp->rrs_count < 0) {
-		rrsp->rrs_state += (unsigned long)local_clock();
-		rrsp->rrs_count = RCU_RANDOM_REFRESH;
-	}
-	rrsp->rrs_state = rrsp->rrs_state * RCU_RANDOM_MULT + RCU_RANDOM_ADD;
-	return swahw32(rrsp->rrs_state);
-}
-
-static void
-rcu_stutter_wait(const char *title)
-{
-	while (stutter_pause_test || !rcutorture_runnable) {
-		if (rcutorture_runnable)
-			schedule_timeout_interruptible(1);
-		else
-			schedule_timeout_interruptible(round_jiffies_relative(HZ));
-		rcutorture_shutdown_absorb(title);
-	}
-}
-
 /*
  * Operations vector for selecting different types of tests.
  */
@@ -365,7 +216,7 @@ rcu_stutter_wait(const char *title)
 struct rcu_torture_ops {
 	void (*init)(void);
 	int (*readlock)(void);
-	void (*read_delay)(struct rcu_random_state *rrsp);
+	void (*read_delay)(struct torture_random_state *rrsp);
 	void (*readunlock)(int idx);
 	int (*completed)(void);
 	void (*deferred_free)(struct rcu_torture *p);
@@ -392,7 +243,7 @@ static int rcu_torture_read_lock(void) __acquires(RCU)
 	return 0;
 }
 
-static void rcu_read_delay(struct rcu_random_state *rrsp)
+static void rcu_read_delay(struct torture_random_state *rrsp)
 {
 	const unsigned long shortdelay_us = 200;
 	const unsigned long longdelay_ms = 50;
@@ -401,12 +252,13 @@ static void rcu_read_delay(struct rcu_random_state *rrsp)
 	 * period, and we want a long delay occasionally to trigger
 	 * force_quiescent_state. */
 
-	if (!(rcu_random(rrsp) % (nrealreaders * 2000 * longdelay_ms)))
+	if (!(torture_random(rrsp) % (nrealreaders * 2000 * longdelay_ms)))
 		mdelay(longdelay_ms);
-	if (!(rcu_random(rrsp) % (nrealreaders * 2 * shortdelay_us)))
+	if (!(torture_random(rrsp) % (nrealreaders * 2 * shortdelay_us)))
 		udelay(shortdelay_us);
 #ifdef CONFIG_PREEMPT
-	if (!preempt_count() && !(rcu_random(rrsp) % (nrealreaders * 20000)))
+	if (!preempt_count() &&
+	    !(torture_random(rrsp) % (nrealreaders * 20000)))
 		preempt_schedule();  /* No QS if preempt_disable() in effect */
 #endif
 }
@@ -427,7 +279,7 @@ rcu_torture_cb(struct rcu_head *p)
 	int i;
 	struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu);
 
-	if (fullstop != FULLSTOP_DONTSTOP) {
+	if (torture_must_stop_irq()) {
 		/* Test is ending, just drop callbacks on the floor. */
 		/* The next initialization will pick up the pieces. */
 		return;
@@ -520,6 +372,48 @@ static struct rcu_torture_ops rcu_bh_ops = {
 };
 
 /*
+ * Don't even think about trying any of these in real life!!!
+ * The names includes "busted", and they really means it!
+ * The only purpose of these functions is to provide a buggy RCU
+ * implementation to make sure that rcutorture correctly emits
+ * buggy-RCU error messages.
+ */
+static void rcu_busted_torture_deferred_free(struct rcu_torture *p)
+{
+	/* This is a deliberate bug for testing purposes only! */
+	rcu_torture_cb(&p->rtort_rcu);
+}
+
+static void synchronize_rcu_busted(void)
+{
+	/* This is a deliberate bug for testing purposes only! */
+}
+
+static void
+call_rcu_busted(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+{
+	/* This is a deliberate bug for testing purposes only! */
+	func(head);
+}
+
+static struct rcu_torture_ops rcu_busted_ops = {
+	.init		= rcu_sync_torture_init,
+	.readlock	= rcu_torture_read_lock,
+	.read_delay	= rcu_read_delay,  /* just reuse rcu's version. */
+	.readunlock	= rcu_torture_read_unlock,
+	.completed	= rcu_no_completed,
+	.deferred_free	= rcu_busted_torture_deferred_free,
+	.sync		= synchronize_rcu_busted,
+	.exp_sync	= synchronize_rcu_busted,
+	.call		= call_rcu_busted,
+	.cb_barrier	= NULL,
+	.fqs		= NULL,
+	.stats		= NULL,
+	.irq_capable	= 1,
+	.name		= "rcu_busted"
+};
+
+/*
  * Definitions for srcu torture testing.
  */
 
@@ -530,7 +424,7 @@ static int srcu_torture_read_lock(void) __acquires(&srcu_ctl)
 	return srcu_read_lock(&srcu_ctl);
 }
 
-static void srcu_read_delay(struct rcu_random_state *rrsp)
+static void srcu_read_delay(struct torture_random_state *rrsp)
 {
 	long delay;
 	const long uspertick = 1000000 / HZ;
@@ -538,7 +432,8 @@ static void srcu_read_delay(struct rcu_random_state *rrsp)
 
 	/* We want there to be long-running readers, but not all the time. */
 
-	delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay * uspertick);
+	delay = torture_random(rrsp) %
+		(nrealreaders * 2 * longdelay * uspertick);
 	if (!delay)
 		schedule_timeout_interruptible(longdelay);
 	else
@@ -677,12 +572,12 @@ static int rcu_torture_boost(void *arg)
 	struct rcu_boost_inflight rbi = { .inflight = 0 };
 	struct sched_param sp;
 
-	VERBOSE_PRINTK_STRING("rcu_torture_boost started");
+	VERBOSE_TOROUT_STRING("rcu_torture_boost started");
 
 	/* Set real-time priority. */
 	sp.sched_priority = 1;
 	if (sched_setscheduler(current, SCHED_FIFO, &sp) < 0) {
-		VERBOSE_PRINTK_STRING("rcu_torture_boost RT prio failed!");
+		VERBOSE_TOROUT_STRING("rcu_torture_boost RT prio failed!");
 		n_rcu_torture_boost_rterror++;
 	}
 
@@ -693,9 +588,8 @@ static int rcu_torture_boost(void *arg)
 		oldstarttime = boost_starttime;
 		while (ULONG_CMP_LT(jiffies, oldstarttime)) {
 			schedule_timeout_interruptible(oldstarttime - jiffies);
-			rcu_stutter_wait("rcu_torture_boost");
-			if (kthread_should_stop() ||
-			    fullstop != FULLSTOP_DONTSTOP)
+			stutter_wait("rcu_torture_boost");
+			if (torture_must_stop())
 				goto checkwait;
 		}
 
@@ -710,15 +604,14 @@ static int rcu_torture_boost(void *arg)
 				call_rcu(&rbi.rcu, rcu_torture_boost_cb);
 				if (jiffies - call_rcu_time >
 					 test_boost_duration * HZ - HZ / 2) {
-					VERBOSE_PRINTK_STRING("rcu_torture_boost boosting failed");
+					VERBOSE_TOROUT_STRING("rcu_torture_boost boosting failed");
 					n_rcu_torture_boost_failure++;
 				}
 				call_rcu_time = jiffies;
 			}
 			cond_resched();
-			rcu_stutter_wait("rcu_torture_boost");
-			if (kthread_should_stop() ||
-			    fullstop != FULLSTOP_DONTSTOP)
+			stutter_wait("rcu_torture_boost");
+			if (torture_must_stop())
 				goto checkwait;
 		}
 
@@ -742,16 +635,17 @@ static int rcu_torture_boost(void *arg)
 		}
 
 		/* Go do the stutter. */
-checkwait:	rcu_stutter_wait("rcu_torture_boost");
-	} while (!kthread_should_stop() && fullstop  == FULLSTOP_DONTSTOP);
+checkwait:	stutter_wait("rcu_torture_boost");
+	} while (!torture_must_stop());
 
 	/* Clean up and exit. */
-	VERBOSE_PRINTK_STRING("rcu_torture_boost task stopping");
-	rcutorture_shutdown_absorb("rcu_torture_boost");
-	while (!kthread_should_stop() || rbi.inflight)
+	while (!kthread_should_stop() || rbi.inflight) {
+		torture_shutdown_absorb("rcu_torture_boost");
 		schedule_timeout_uninterruptible(1);
+	}
 	smp_mb(); /* order accesses to ->inflight before stack-frame death. */
 	destroy_rcu_head_on_stack(&rbi.rcu);
+	torture_kthread_stopping("rcu_torture_boost");
 	return 0;
 }
 
@@ -766,7 +660,7 @@ rcu_torture_fqs(void *arg)
 	unsigned long fqs_resume_time;
 	int fqs_burst_remaining;
 
-	VERBOSE_PRINTK_STRING("rcu_torture_fqs task started");
+	VERBOSE_TOROUT_STRING("rcu_torture_fqs task started");
 	do {
 		fqs_resume_time = jiffies + fqs_stutter * HZ;
 		while (ULONG_CMP_LT(jiffies, fqs_resume_time) &&
@@ -780,12 +674,9 @@ rcu_torture_fqs(void *arg)
 			udelay(fqs_holdoff);
 			fqs_burst_remaining -= fqs_holdoff;
 		}
-		rcu_stutter_wait("rcu_torture_fqs");
-	} while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
-	VERBOSE_PRINTK_STRING("rcu_torture_fqs task stopping");
-	rcutorture_shutdown_absorb("rcu_torture_fqs");
-	while (!kthread_should_stop())
-		schedule_timeout_uninterruptible(1);
+		stutter_wait("rcu_torture_fqs");
+	} while (!torture_must_stop());
+	torture_kthread_stopping("rcu_torture_fqs");
 	return 0;
 }
 
@@ -802,10 +693,10 @@ rcu_torture_writer(void *arg)
 	struct rcu_torture *rp;
 	struct rcu_torture *rp1;
 	struct rcu_torture *old_rp;
-	static DEFINE_RCU_RANDOM(rand);
+	static DEFINE_TORTURE_RANDOM(rand);
 
-	VERBOSE_PRINTK_STRING("rcu_torture_writer task started");
-	set_user_nice(current, 19);
+	VERBOSE_TOROUT_STRING("rcu_torture_writer task started");
+	set_user_nice(current, MAX_NICE);
 
 	do {
 		schedule_timeout_uninterruptible(1);
@@ -813,7 +704,7 @@ rcu_torture_writer(void *arg)
 		if (rp == NULL)
 			continue;
 		rp->rtort_pipe_count = 0;
-		udelay(rcu_random(&rand) & 0x3ff);
+		udelay(torture_random(&rand) & 0x3ff);
 		old_rp = rcu_dereference_check(rcu_torture_current,
 					       current == writer_task);
 		rp->rtort_mbtest = 1;
@@ -826,7 +717,7 @@ rcu_torture_writer(void *arg)
 			atomic_inc(&rcu_torture_wcount[i]);
 			old_rp->rtort_pipe_count++;
 			if (gp_normal == gp_exp)
-				exp = !!(rcu_random(&rand) & 0x80);
+				exp = !!(torture_random(&rand) & 0x80);
 			else
 				exp = gp_exp;
 			if (!exp) {
@@ -852,12 +743,9 @@ rcu_torture_writer(void *arg)
 			}
 		}
 		rcutorture_record_progress(++rcu_torture_current_version);
-		rcu_stutter_wait("rcu_torture_writer");
-	} while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
-	VERBOSE_PRINTK_STRING("rcu_torture_writer task stopping");
-	rcutorture_shutdown_absorb("rcu_torture_writer");
-	while (!kthread_should_stop())
-		schedule_timeout_uninterruptible(1);
+		stutter_wait("rcu_torture_writer");
+	} while (!torture_must_stop());
+	torture_kthread_stopping("rcu_torture_writer");
 	return 0;
 }
 
@@ -868,19 +756,19 @@ rcu_torture_writer(void *arg)
 static int
 rcu_torture_fakewriter(void *arg)
 {
-	DEFINE_RCU_RANDOM(rand);
+	DEFINE_TORTURE_RANDOM(rand);
 
-	VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task started");
-	set_user_nice(current, 19);
+	VERBOSE_TOROUT_STRING("rcu_torture_fakewriter task started");
+	set_user_nice(current, MAX_NICE);
 
 	do {
-		schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10);
-		udelay(rcu_random(&rand) & 0x3ff);
+		schedule_timeout_uninterruptible(1 + torture_random(&rand)%10);
+		udelay(torture_random(&rand) & 0x3ff);
 		if (cur_ops->cb_barrier != NULL &&
-		    rcu_random(&rand) % (nfakewriters * 8) == 0) {
+		    torture_random(&rand) % (nfakewriters * 8) == 0) {
 			cur_ops->cb_barrier();
 		} else if (gp_normal == gp_exp) {
-			if (rcu_random(&rand) & 0x80)
+			if (torture_random(&rand) & 0x80)
 				cur_ops->sync();
 			else
 				cur_ops->exp_sync();
@@ -889,13 +777,10 @@ rcu_torture_fakewriter(void *arg)
 		} else {
 			cur_ops->exp_sync();
 		}
-		rcu_stutter_wait("rcu_torture_fakewriter");
-	} while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
+		stutter_wait("rcu_torture_fakewriter");
+	} while (!torture_must_stop());
 
-	VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task stopping");
-	rcutorture_shutdown_absorb("rcu_torture_fakewriter");
-	while (!kthread_should_stop())
-		schedule_timeout_uninterruptible(1);
+	torture_kthread_stopping("rcu_torture_fakewriter");
 	return 0;
 }
 
@@ -921,7 +806,7 @@ static void rcu_torture_timer(unsigned long unused)
 	int idx;
 	int completed;
 	int completed_end;
-	static DEFINE_RCU_RANDOM(rand);
+	static DEFINE_TORTURE_RANDOM(rand);
 	static DEFINE_SPINLOCK(rand_lock);
 	struct rcu_torture *p;
 	int pipe_count;
@@ -980,14 +865,14 @@ rcu_torture_reader(void *arg)
 	int completed;
 	int completed_end;
 	int idx;
-	DEFINE_RCU_RANDOM(rand);
+	DEFINE_TORTURE_RANDOM(rand);
 	struct rcu_torture *p;
 	int pipe_count;
 	struct timer_list t;
 	unsigned long long ts;
 
-	VERBOSE_PRINTK_STRING("rcu_torture_reader task started");
-	set_user_nice(current, 19);
+	VERBOSE_TOROUT_STRING("rcu_torture_reader task started");
+	set_user_nice(current, MAX_NICE);
 	if (irqreader && cur_ops->irq_capable)
 		setup_timer_on_stack(&t, rcu_torture_timer, 0);
 
@@ -1034,14 +919,11 @@ rcu_torture_reader(void *arg)
 		preempt_enable();
 		cur_ops->readunlock(idx);
 		schedule();
-		rcu_stutter_wait("rcu_torture_reader");
-	} while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
-	VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping");
-	rcutorture_shutdown_absorb("rcu_torture_reader");
+		stutter_wait("rcu_torture_reader");
+	} while (!torture_must_stop());
 	if (irqreader && cur_ops->irq_capable)
 		del_timer_sync(&t);
-	while (!kthread_should_stop())
-		schedule_timeout_uninterruptible(1);
+	torture_kthread_stopping("rcu_torture_reader");
 	return 0;
 }
 
@@ -1083,13 +965,7 @@ rcu_torture_printk(char *page)
 		       n_rcu_torture_boost_failure,
 		       n_rcu_torture_boosts,
 		       n_rcu_torture_timers);
-	page += sprintf(page,
-		       "onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ",
-		       n_online_successes, n_online_attempts,
-		       n_offline_successes, n_offline_attempts,
-		       min_online, max_online,
-		       min_offline, max_offline,
-		       sum_online, sum_offline, HZ);
+	page = torture_onoff_stats(page);
 	page += sprintf(page, "barrier: %ld/%ld:%ld",
 		       n_barrier_successes,
 		       n_barrier_attempts,
@@ -1150,123 +1026,17 @@ rcu_torture_stats_print(void)
 /*
  * Periodically prints torture statistics, if periodic statistics printing
  * was specified via the stat_interval module parameter.
- *
- * No need to worry about fullstop here, since this one doesn't reference
- * volatile state or register callbacks.
  */
 static int
 rcu_torture_stats(void *arg)
 {
-	VERBOSE_PRINTK_STRING("rcu_torture_stats task started");
+	VERBOSE_TOROUT_STRING("rcu_torture_stats task started");
 	do {
 		schedule_timeout_interruptible(stat_interval * HZ);
 		rcu_torture_stats_print();
-		rcutorture_shutdown_absorb("rcu_torture_stats");
-	} while (!kthread_should_stop());
-	VERBOSE_PRINTK_STRING("rcu_torture_stats task stopping");
-	return 0;
-}
-
-static int rcu_idle_cpu;	/* Force all torture tasks off this CPU */
-
-/* Shuffle tasks such that we allow @rcu_idle_cpu to become idle. A special case
- * is when @rcu_idle_cpu = -1, when we allow the tasks to run on all CPUs.
- */
-static void rcu_torture_shuffle_tasks(void)
-{
-	int i;
-
-	cpumask_setall(shuffle_tmp_mask);
-	get_online_cpus();
-
-	/* No point in shuffling if there is only one online CPU (ex: UP) */
-	if (num_online_cpus() == 1) {
-		put_online_cpus();
-		return;
-	}
-
-	if (rcu_idle_cpu != -1)
-		cpumask_clear_cpu(rcu_idle_cpu, shuffle_tmp_mask);
-
-	set_cpus_allowed_ptr(current, shuffle_tmp_mask);
-
-	if (reader_tasks) {
-		for (i = 0; i < nrealreaders; i++)
-			if (reader_tasks[i])
-				set_cpus_allowed_ptr(reader_tasks[i],
-						     shuffle_tmp_mask);
-	}
-	if (fakewriter_tasks) {
-		for (i = 0; i < nfakewriters; i++)
-			if (fakewriter_tasks[i])
-				set_cpus_allowed_ptr(fakewriter_tasks[i],
-						     shuffle_tmp_mask);
-	}
-	if (writer_task)
-		set_cpus_allowed_ptr(writer_task, shuffle_tmp_mask);
-	if (stats_task)
-		set_cpus_allowed_ptr(stats_task, shuffle_tmp_mask);
-	if (stutter_task)
-		set_cpus_allowed_ptr(stutter_task, shuffle_tmp_mask);
-	if (fqs_task)
-		set_cpus_allowed_ptr(fqs_task, shuffle_tmp_mask);
-	if (shutdown_task)
-		set_cpus_allowed_ptr(shutdown_task, shuffle_tmp_mask);
-#ifdef CONFIG_HOTPLUG_CPU
-	if (onoff_task)
-		set_cpus_allowed_ptr(onoff_task, shuffle_tmp_mask);
-#endif /* #ifdef CONFIG_HOTPLUG_CPU */
-	if (stall_task)
-		set_cpus_allowed_ptr(stall_task, shuffle_tmp_mask);
-	if (barrier_cbs_tasks)
-		for (i = 0; i < n_barrier_cbs; i++)
-			if (barrier_cbs_tasks[i])
-				set_cpus_allowed_ptr(barrier_cbs_tasks[i],
-						     shuffle_tmp_mask);
-	if (barrier_task)
-		set_cpus_allowed_ptr(barrier_task, shuffle_tmp_mask);
-
-	if (rcu_idle_cpu == -1)
-		rcu_idle_cpu = num_online_cpus() - 1;
-	else
-		rcu_idle_cpu--;
-
-	put_online_cpus();
-}
-
-/* Shuffle tasks across CPUs, with the intent of allowing each CPU in the
- * system to become idle at a time and cut off its timer ticks. This is meant
- * to test the support for such tickless idle CPU in RCU.
- */
-static int
-rcu_torture_shuffle(void *arg)
-{
-	VERBOSE_PRINTK_STRING("rcu_torture_shuffle task started");
-	do {
-		schedule_timeout_interruptible(shuffle_interval * HZ);
-		rcu_torture_shuffle_tasks();
-		rcutorture_shutdown_absorb("rcu_torture_shuffle");
-	} while (!kthread_should_stop());
-	VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping");
-	return 0;
-}
-
-/* Cause the rcutorture test to "stutter", starting and stopping all
- * threads periodically.
- */
-static int
-rcu_torture_stutter(void *arg)
-{
-	VERBOSE_PRINTK_STRING("rcu_torture_stutter task started");
-	do {
-		schedule_timeout_interruptible(stutter * HZ);
-		stutter_pause_test = 1;
-		if (!kthread_should_stop())
-			schedule_timeout_interruptible(stutter * HZ);
-		stutter_pause_test = 0;
-		rcutorture_shutdown_absorb("rcu_torture_stutter");
-	} while (!kthread_should_stop());
-	VERBOSE_PRINTK_STRING("rcu_torture_stutter task stopping");
+		torture_shutdown_absorb("rcu_torture_stats");
+	} while (!torture_must_stop());
+	torture_kthread_stopping("rcu_torture_stats");
 	return 0;
 }
 
@@ -1293,10 +1063,6 @@ rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, const char *tag)
 		 onoff_interval, onoff_holdoff);
 }
 
-static struct notifier_block rcutorture_shutdown_nb = {
-	.notifier_call = rcutorture_shutdown_notify,
-};
-
 static void rcutorture_booster_cleanup(int cpu)
 {
 	struct task_struct *t;
@@ -1304,14 +1070,12 @@ static void rcutorture_booster_cleanup(int cpu)
 	if (boost_tasks[cpu] == NULL)
 		return;
 	mutex_lock(&boost_mutex);
-	VERBOSE_PRINTK_STRING("Stopping rcu_torture_boost task");
 	t = boost_tasks[cpu];
 	boost_tasks[cpu] = NULL;
 	mutex_unlock(&boost_mutex);
 
 	/* This must be outside of the mutex, otherwise deadlock! */
-	kthread_stop(t);
-	boost_tasks[cpu] = NULL;
+	torture_stop_kthread(rcu_torture_boost, t);
 }
 
 static int rcutorture_booster_init(int cpu)
@@ -1323,13 +1087,13 @@ static int rcutorture_booster_init(int cpu)
 
 	/* Don't allow time recalculation while creating a new task. */
 	mutex_lock(&boost_mutex);
-	VERBOSE_PRINTK_STRING("Creating rcu_torture_boost task");
+	VERBOSE_TOROUT_STRING("Creating rcu_torture_boost task");
 	boost_tasks[cpu] = kthread_create_on_node(rcu_torture_boost, NULL,
 						  cpu_to_node(cpu),
 						  "rcu_torture_boost");
 	if (IS_ERR(boost_tasks[cpu])) {
 		retval = PTR_ERR(boost_tasks[cpu]);
-		VERBOSE_PRINTK_STRING("rcu_torture_boost task create failed");
+		VERBOSE_TOROUT_STRING("rcu_torture_boost task create failed");
 		n_rcu_torture_boost_ktrerror++;
 		boost_tasks[cpu] = NULL;
 		mutex_unlock(&boost_mutex);
@@ -1342,175 +1106,6 @@ static int rcutorture_booster_init(int cpu)
 }
 
 /*
- * Cause the rcutorture test to shutdown the system after the test has
- * run for the time specified by the shutdown_secs module parameter.
- */
-static int
-rcu_torture_shutdown(void *arg)
-{
-	long delta;
-	unsigned long jiffies_snap;
-
-	VERBOSE_PRINTK_STRING("rcu_torture_shutdown task started");
-	jiffies_snap = ACCESS_ONCE(jiffies);
-	while (ULONG_CMP_LT(jiffies_snap, shutdown_time) &&
-	       !kthread_should_stop()) {
-		delta = shutdown_time - jiffies_snap;
-		if (verbose)
-			pr_alert("%s" TORTURE_FLAG
-				 "rcu_torture_shutdown task: %lu jiffies remaining\n",
-				 torture_type, delta);
-		schedule_timeout_interruptible(delta);
-		jiffies_snap = ACCESS_ONCE(jiffies);
-	}
-	if (kthread_should_stop()) {
-		VERBOSE_PRINTK_STRING("rcu_torture_shutdown task stopping");
-		return 0;
-	}
-
-	/* OK, shut down the system. */
-
-	VERBOSE_PRINTK_STRING("rcu_torture_shutdown task shutting down system");
-	shutdown_task = NULL;	/* Avoid self-kill deadlock. */
-	rcu_torture_cleanup();	/* Get the success/failure message. */
-	kernel_power_off();	/* Shut down the system. */
-	return 0;
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-
-/*
- * Execute random CPU-hotplug operations at the interval specified
- * by the onoff_interval.
- */
-static int
-rcu_torture_onoff(void *arg)
-{
-	int cpu;
-	unsigned long delta;
-	int maxcpu = -1;
-	DEFINE_RCU_RANDOM(rand);
-	int ret;
-	unsigned long starttime;
-
-	VERBOSE_PRINTK_STRING("rcu_torture_onoff task started");
-	for_each_online_cpu(cpu)
-		maxcpu = cpu;
-	WARN_ON(maxcpu < 0);
-	if (onoff_holdoff > 0) {
-		VERBOSE_PRINTK_STRING("rcu_torture_onoff begin holdoff");
-		schedule_timeout_interruptible(onoff_holdoff * HZ);
-		VERBOSE_PRINTK_STRING("rcu_torture_onoff end holdoff");
-	}
-	while (!kthread_should_stop()) {
-		cpu = (rcu_random(&rand) >> 4) % (maxcpu + 1);
-		if (cpu_online(cpu) && cpu_is_hotpluggable(cpu)) {
-			if (verbose)
-				pr_alert("%s" TORTURE_FLAG
-					 "rcu_torture_onoff task: offlining %d\n",
-					 torture_type, cpu);
-			starttime = jiffies;
-			n_offline_attempts++;
-			ret = cpu_down(cpu);
-			if (ret) {
-				if (verbose)
-					pr_alert("%s" TORTURE_FLAG
-						 "rcu_torture_onoff task: offline %d failed: errno %d\n",
-						 torture_type, cpu, ret);
-			} else {
-				if (verbose)
-					pr_alert("%s" TORTURE_FLAG
-						 "rcu_torture_onoff task: offlined %d\n",
-						 torture_type, cpu);
-				n_offline_successes++;
-				delta = jiffies - starttime;
-				sum_offline += delta;
-				if (min_offline < 0) {
-					min_offline = delta;
-					max_offline = delta;
-				}
-				if (min_offline > delta)
-					min_offline = delta;
-				if (max_offline < delta)
-					max_offline = delta;
-			}
-		} else if (cpu_is_hotpluggable(cpu)) {
-			if (verbose)
-				pr_alert("%s" TORTURE_FLAG
-					 "rcu_torture_onoff task: onlining %d\n",
-					 torture_type, cpu);
-			starttime = jiffies;
-			n_online_attempts++;
-			ret = cpu_up(cpu);
-			if (ret) {
-				if (verbose)
-					pr_alert("%s" TORTURE_FLAG
-						 "rcu_torture_onoff task: online %d failed: errno %d\n",
-						 torture_type, cpu, ret);
-			} else {
-				if (verbose)
-					pr_alert("%s" TORTURE_FLAG
-						 "rcu_torture_onoff task: onlined %d\n",
-						 torture_type, cpu);
-				n_online_successes++;
-				delta = jiffies - starttime;
-				sum_online += delta;
-				if (min_online < 0) {
-					min_online = delta;
-					max_online = delta;
-				}
-				if (min_online > delta)
-					min_online = delta;
-				if (max_online < delta)
-					max_online = delta;
-			}
-		}
-		schedule_timeout_interruptible(onoff_interval * HZ);
-	}
-	VERBOSE_PRINTK_STRING("rcu_torture_onoff task stopping");
-	return 0;
-}
-
-static int
-rcu_torture_onoff_init(void)
-{
-	int ret;
-
-	if (onoff_interval <= 0)
-		return 0;
-	onoff_task = kthread_run(rcu_torture_onoff, NULL, "rcu_torture_onoff");
-	if (IS_ERR(onoff_task)) {
-		ret = PTR_ERR(onoff_task);
-		onoff_task = NULL;
-		return ret;
-	}
-	return 0;
-}
-
-static void rcu_torture_onoff_cleanup(void)
-{
-	if (onoff_task == NULL)
-		return;
-	VERBOSE_PRINTK_STRING("Stopping rcu_torture_onoff task");
-	kthread_stop(onoff_task);
-	onoff_task = NULL;
-}
-
-#else /* #ifdef CONFIG_HOTPLUG_CPU */
-
-static int
-rcu_torture_onoff_init(void)
-{
-	return 0;
-}
-
-static void rcu_torture_onoff_cleanup(void)
-{
-}
-
-#endif /* #else #ifdef CONFIG_HOTPLUG_CPU */
-
-/*
  * CPU-stall kthread.  It waits as specified by stall_cpu_holdoff, then
  * induces a CPU stall for the time specified by stall_cpu.
  */
@@ -1518,11 +1113,11 @@ static int rcu_torture_stall(void *args)
 {
 	unsigned long stop_at;
 
-	VERBOSE_PRINTK_STRING("rcu_torture_stall task started");
+	VERBOSE_TOROUT_STRING("rcu_torture_stall task started");
 	if (stall_cpu_holdoff > 0) {
-		VERBOSE_PRINTK_STRING("rcu_torture_stall begin holdoff");
+		VERBOSE_TOROUT_STRING("rcu_torture_stall begin holdoff");
 		schedule_timeout_interruptible(stall_cpu_holdoff * HZ);
-		VERBOSE_PRINTK_STRING("rcu_torture_stall end holdoff");
+		VERBOSE_TOROUT_STRING("rcu_torture_stall end holdoff");
 	}
 	if (!kthread_should_stop()) {
 		stop_at = get_seconds() + stall_cpu;
@@ -1536,7 +1131,7 @@ static int rcu_torture_stall(void *args)
 		rcu_read_unlock();
 		pr_alert("rcu_torture_stall end.\n");
 	}
-	rcutorture_shutdown_absorb("rcu_torture_stall");
+	torture_shutdown_absorb("rcu_torture_stall");
 	while (!kthread_should_stop())
 		schedule_timeout_interruptible(10 * HZ);
 	return 0;
@@ -1545,27 +1140,9 @@ static int rcu_torture_stall(void *args)
 /* Spawn CPU-stall kthread, if stall_cpu specified. */
 static int __init rcu_torture_stall_init(void)
 {
-	int ret;
-
 	if (stall_cpu <= 0)
 		return 0;
-	stall_task = kthread_run(rcu_torture_stall, NULL, "rcu_torture_stall");
-	if (IS_ERR(stall_task)) {
-		ret = PTR_ERR(stall_task);
-		stall_task = NULL;
-		return ret;
-	}
-	return 0;
-}
-
-/* Clean up after the CPU-stall kthread, if one was spawned. */
-static void rcu_torture_stall_cleanup(void)
-{
-	if (stall_task == NULL)
-		return;
-	VERBOSE_PRINTK_STRING("Stopping rcu_torture_stall_task.");
-	kthread_stop(stall_task);
-	stall_task = NULL;
+	return torture_create_kthread(rcu_torture_stall, NULL, stall_task);
 }
 
 /* Callback function for RCU barrier testing. */
@@ -1583,28 +1160,24 @@ static int rcu_torture_barrier_cbs(void *arg)
 	struct rcu_head rcu;
 
 	init_rcu_head_on_stack(&rcu);
-	VERBOSE_PRINTK_STRING("rcu_torture_barrier_cbs task started");
-	set_user_nice(current, 19);
+	VERBOSE_TOROUT_STRING("rcu_torture_barrier_cbs task started");
+	set_user_nice(current, MAX_NICE);
 	do {
 		wait_event(barrier_cbs_wq[myid],
 			   (newphase =
 			    ACCESS_ONCE(barrier_phase)) != lastphase ||
-			   kthread_should_stop() ||
-			   fullstop != FULLSTOP_DONTSTOP);
+			   torture_must_stop());
 		lastphase = newphase;
 		smp_mb(); /* ensure barrier_phase load before ->call(). */
-		if (kthread_should_stop() || fullstop != FULLSTOP_DONTSTOP)
+		if (torture_must_stop())
 			break;
 		cur_ops->call(&rcu, rcu_torture_barrier_cbf);
 		if (atomic_dec_and_test(&barrier_cbs_count))
 			wake_up(&barrier_wq);
-	} while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
-	VERBOSE_PRINTK_STRING("rcu_torture_barrier_cbs task stopping");
-	rcutorture_shutdown_absorb("rcu_torture_barrier_cbs");
-	while (!kthread_should_stop())
-		schedule_timeout_interruptible(1);
+	} while (!torture_must_stop());
 	cur_ops->cb_barrier();
 	destroy_rcu_head_on_stack(&rcu);
+	torture_kthread_stopping("rcu_torture_barrier_cbs");
 	return 0;
 }
 
@@ -1613,7 +1186,7 @@ static int rcu_torture_barrier(void *arg)
 {
 	int i;
 
-	VERBOSE_PRINTK_STRING("rcu_torture_barrier task starting");
+	VERBOSE_TOROUT_STRING("rcu_torture_barrier task starting");
 	do {
 		atomic_set(&barrier_cbs_invoked, 0);
 		atomic_set(&barrier_cbs_count, n_barrier_cbs);
@@ -1623,9 +1196,8 @@ static int rcu_torture_barrier(void *arg)
 			wake_up(&barrier_cbs_wq[i]);
 		wait_event(barrier_wq,
 			   atomic_read(&barrier_cbs_count) == 0 ||
-			   kthread_should_stop() ||
-			   fullstop != FULLSTOP_DONTSTOP);
-		if (kthread_should_stop() || fullstop != FULLSTOP_DONTSTOP)
+			   torture_must_stop());
+		if (torture_must_stop())
 			break;
 		n_barrier_attempts++;
 		cur_ops->cb_barrier(); /* Implies smp_mb() for wait_event(). */
@@ -1635,11 +1207,8 @@ static int rcu_torture_barrier(void *arg)
 		}
 		n_barrier_successes++;
 		schedule_timeout_interruptible(HZ / 10);
-	} while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
-	VERBOSE_PRINTK_STRING("rcu_torture_barrier task stopping");
-	rcutorture_shutdown_absorb("rcu_torture_barrier");
-	while (!kthread_should_stop())
-		schedule_timeout_interruptible(1);
+	} while (!torture_must_stop());
+	torture_kthread_stopping("rcu_torture_barrier");
 	return 0;
 }
 
@@ -1672,24 +1241,13 @@ static int rcu_torture_barrier_init(void)
 		return -ENOMEM;
 	for (i = 0; i < n_barrier_cbs; i++) {
 		init_waitqueue_head(&barrier_cbs_wq[i]);
-		barrier_cbs_tasks[i] = kthread_run(rcu_torture_barrier_cbs,
-						   (void *)(long)i,
-						   "rcu_torture_barrier_cbs");
-		if (IS_ERR(barrier_cbs_tasks[i])) {
-			ret = PTR_ERR(barrier_cbs_tasks[i]);
-			VERBOSE_PRINTK_ERRSTRING("Failed to create rcu_torture_barrier_cbs");
-			barrier_cbs_tasks[i] = NULL;
+		ret = torture_create_kthread(rcu_torture_barrier_cbs,
+					     (void *)(long)i,
+					     barrier_cbs_tasks[i]);
+		if (ret)
 			return ret;
-		}
 	}
-	barrier_task = kthread_run(rcu_torture_barrier, NULL,
-				   "rcu_torture_barrier");
-	if (IS_ERR(barrier_task)) {
-		ret = PTR_ERR(barrier_task);
-		VERBOSE_PRINTK_ERRSTRING("Failed to create rcu_torture_barrier");
-		barrier_task = NULL;
-	}
-	return 0;
+	return torture_create_kthread(rcu_torture_barrier, NULL, barrier_task);
 }
 
 /* Clean up after RCU barrier testing. */
@@ -1697,19 +1255,11 @@ static void rcu_torture_barrier_cleanup(void)
 {
 	int i;
 
-	if (barrier_task != NULL) {
-		VERBOSE_PRINTK_STRING("Stopping rcu_torture_barrier task");
-		kthread_stop(barrier_task);
-		barrier_task = NULL;
-	}
+	torture_stop_kthread(rcu_torture_barrier, barrier_task);
 	if (barrier_cbs_tasks != NULL) {
-		for (i = 0; i < n_barrier_cbs; i++) {
-			if (barrier_cbs_tasks[i] != NULL) {
-				VERBOSE_PRINTK_STRING("Stopping rcu_torture_barrier_cbs task");
-				kthread_stop(barrier_cbs_tasks[i]);
-				barrier_cbs_tasks[i] = NULL;
-			}
-		}
+		for (i = 0; i < n_barrier_cbs; i++)
+			torture_stop_kthread(rcu_torture_barrier_cbs,
+					     barrier_cbs_tasks[i]);
 		kfree(barrier_cbs_tasks);
 		barrier_cbs_tasks = NULL;
 	}
@@ -1747,90 +1297,42 @@ rcu_torture_cleanup(void)
 {
 	int i;
 
-	mutex_lock(&fullstop_mutex);
 	rcutorture_record_test_transition();
-	if (fullstop == FULLSTOP_SHUTDOWN) {
-		pr_warn(/* but going down anyway, so... */
-		       "Concurrent 'rmmod rcutorture' and shutdown illegal!\n");
-		mutex_unlock(&fullstop_mutex);
-		schedule_timeout_uninterruptible(10);
+	if (torture_cleanup()) {
 		if (cur_ops->cb_barrier != NULL)
 			cur_ops->cb_barrier();
 		return;
 	}
-	fullstop = FULLSTOP_RMMOD;
-	mutex_unlock(&fullstop_mutex);
-	unregister_reboot_notifier(&rcutorture_shutdown_nb);
-	rcu_torture_barrier_cleanup();
-	rcu_torture_stall_cleanup();
-	if (stutter_task) {
-		VERBOSE_PRINTK_STRING("Stopping rcu_torture_stutter task");
-		kthread_stop(stutter_task);
-	}
-	stutter_task = NULL;
-	if (shuffler_task) {
-		VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task");
-		kthread_stop(shuffler_task);
-		free_cpumask_var(shuffle_tmp_mask);
-	}
-	shuffler_task = NULL;
 
-	if (writer_task) {
-		VERBOSE_PRINTK_STRING("Stopping rcu_torture_writer task");
-		kthread_stop(writer_task);
-	}
-	writer_task = NULL;
+	rcu_torture_barrier_cleanup();
+	torture_stop_kthread(rcu_torture_stall, stall_task);
+	torture_stop_kthread(rcu_torture_writer, writer_task);
 
 	if (reader_tasks) {
-		for (i = 0; i < nrealreaders; i++) {
-			if (reader_tasks[i]) {
-				VERBOSE_PRINTK_STRING(
-					"Stopping rcu_torture_reader task");
-				kthread_stop(reader_tasks[i]);
-			}
-			reader_tasks[i] = NULL;
-		}
+		for (i = 0; i < nrealreaders; i++)
+			torture_stop_kthread(rcu_torture_reader,
+					     reader_tasks[i]);
 		kfree(reader_tasks);
-		reader_tasks = NULL;
 	}
 	rcu_torture_current = NULL;
 
 	if (fakewriter_tasks) {
 		for (i = 0; i < nfakewriters; i++) {
-			if (fakewriter_tasks[i]) {
-				VERBOSE_PRINTK_STRING(
-					"Stopping rcu_torture_fakewriter task");
-				kthread_stop(fakewriter_tasks[i]);
-			}
-			fakewriter_tasks[i] = NULL;
+			torture_stop_kthread(rcu_torture_fakewriter,
+					     fakewriter_tasks[i]);
 		}
 		kfree(fakewriter_tasks);
 		fakewriter_tasks = NULL;
 	}
 
-	if (stats_task) {
-		VERBOSE_PRINTK_STRING("Stopping rcu_torture_stats task");
-		kthread_stop(stats_task);
-	}
-	stats_task = NULL;
-
-	if (fqs_task) {
-		VERBOSE_PRINTK_STRING("Stopping rcu_torture_fqs task");
-		kthread_stop(fqs_task);
-	}
-	fqs_task = NULL;
+	torture_stop_kthread(rcu_torture_stats, stats_task);
+	torture_stop_kthread(rcu_torture_fqs, fqs_task);
 	if ((test_boost == 1 && cur_ops->can_boost) ||
 	    test_boost == 2) {
 		unregister_cpu_notifier(&rcutorture_cpu_nb);
 		for_each_possible_cpu(i)
 			rcutorture_booster_cleanup(i);
 	}
-	if (shutdown_task != NULL) {
-		VERBOSE_PRINTK_STRING("Stopping rcu_torture_shutdown task");
-		kthread_stop(shutdown_task);
-	}
-	shutdown_task = NULL;
-	rcu_torture_onoff_cleanup();
 
 	/* Wait for all RCU callbacks to fire.  */
 
@@ -1841,8 +1343,7 @@ rcu_torture_cleanup(void)
 
 	if (atomic_read(&n_rcu_torture_error) || n_rcu_torture_barrier_error)
 		rcu_torture_print_module_parms(cur_ops, "End of test: FAILURE");
-	else if (n_online_successes != n_online_attempts ||
-		 n_offline_successes != n_offline_attempts)
+	else if (torture_onoff_failures())
 		rcu_torture_print_module_parms(cur_ops,
 					       "End of test: RCU_HOTPLUG");
 	else
@@ -1911,12 +1412,11 @@ rcu_torture_init(void)
 	int i;
 	int cpu;
 	int firsterr = 0;
-	int retval;
 	static struct rcu_torture_ops *torture_ops[] = {
-		&rcu_ops, &rcu_bh_ops, &srcu_ops, &sched_ops,
+		&rcu_ops, &rcu_bh_ops, &rcu_busted_ops, &srcu_ops, &sched_ops,
 	};
 
-	mutex_lock(&fullstop_mutex);
+	torture_init_begin(torture_type, verbose, &rcutorture_runnable);
 
 	/* Process args and tell the world that the torturer is on the job. */
 	for (i = 0; i < ARRAY_SIZE(torture_ops); i++) {
@@ -1931,7 +1431,7 @@ rcu_torture_init(void)
 		for (i = 0; i < ARRAY_SIZE(torture_ops); i++)
 			pr_alert(" %s", torture_ops[i]->name);
 		pr_alert("\n");
-		mutex_unlock(&fullstop_mutex);
+		torture_init_end();
 		return -EINVAL;
 	}
 	if (cur_ops->fqs == NULL && fqs_duration != 0) {
@@ -1946,7 +1446,6 @@ rcu_torture_init(void)
 	else
 		nrealreaders = 2 * num_online_cpus();
 	rcu_torture_print_module_parms(cur_ops, "Start of test");
-	fullstop = FULLSTOP_DONTSTOP;
 
 	/* Set up the freelist. */
 
@@ -1982,108 +1481,61 @@ rcu_torture_init(void)
 
 	/* Start up the kthreads. */
 
-	VERBOSE_PRINTK_STRING("Creating rcu_torture_writer task");
-	writer_task = kthread_create(rcu_torture_writer, NULL,
-				     "rcu_torture_writer");
-	if (IS_ERR(writer_task)) {
-		firsterr = PTR_ERR(writer_task);
-		VERBOSE_PRINTK_ERRSTRING("Failed to create writer");
-		writer_task = NULL;
+	firsterr = torture_create_kthread(rcu_torture_writer, NULL,
+					  writer_task);
+	if (firsterr)
 		goto unwind;
-	}
-	wake_up_process(writer_task);
 	fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]),
 				   GFP_KERNEL);
 	if (fakewriter_tasks == NULL) {
-		VERBOSE_PRINTK_ERRSTRING("out of memory");
+		VERBOSE_TOROUT_ERRSTRING("out of memory");
 		firsterr = -ENOMEM;
 		goto unwind;
 	}
 	for (i = 0; i < nfakewriters; i++) {
-		VERBOSE_PRINTK_STRING("Creating rcu_torture_fakewriter task");
-		fakewriter_tasks[i] = kthread_run(rcu_torture_fakewriter, NULL,
-						  "rcu_torture_fakewriter");
-		if (IS_ERR(fakewriter_tasks[i])) {
-			firsterr = PTR_ERR(fakewriter_tasks[i]);
-			VERBOSE_PRINTK_ERRSTRING("Failed to create fakewriter");
-			fakewriter_tasks[i] = NULL;
+		firsterr = torture_create_kthread(rcu_torture_fakewriter,
+						  NULL, fakewriter_tasks[i]);
+		if (firsterr)
 			goto unwind;
-		}
 	}
 	reader_tasks = kzalloc(nrealreaders * sizeof(reader_tasks[0]),
 			       GFP_KERNEL);
 	if (reader_tasks == NULL) {
-		VERBOSE_PRINTK_ERRSTRING("out of memory");
+		VERBOSE_TOROUT_ERRSTRING("out of memory");
 		firsterr = -ENOMEM;
 		goto unwind;
 	}
 	for (i = 0; i < nrealreaders; i++) {
-		VERBOSE_PRINTK_STRING("Creating rcu_torture_reader task");
-		reader_tasks[i] = kthread_run(rcu_torture_reader, NULL,
-					      "rcu_torture_reader");
-		if (IS_ERR(reader_tasks[i])) {
-			firsterr = PTR_ERR(reader_tasks[i]);
-			VERBOSE_PRINTK_ERRSTRING("Failed to create reader");
-			reader_tasks[i] = NULL;
+		firsterr = torture_create_kthread(rcu_torture_reader, NULL,
+						  reader_tasks[i]);
+		if (firsterr)
 			goto unwind;
-		}
 	}
 	if (stat_interval > 0) {
-		VERBOSE_PRINTK_STRING("Creating rcu_torture_stats task");
-		stats_task = kthread_run(rcu_torture_stats, NULL,
-					"rcu_torture_stats");
-		if (IS_ERR(stats_task)) {
-			firsterr = PTR_ERR(stats_task);
-			VERBOSE_PRINTK_ERRSTRING("Failed to create stats");
-			stats_task = NULL;
+		firsterr = torture_create_kthread(rcu_torture_stats, NULL,
+						  stats_task);
+		if (firsterr)
 			goto unwind;
-		}
 	}
 	if (test_no_idle_hz) {
-		rcu_idle_cpu = num_online_cpus() - 1;
-
-		if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) {
-			firsterr = -ENOMEM;
-			VERBOSE_PRINTK_ERRSTRING("Failed to alloc mask");
-			goto unwind;
-		}
-
-		/* Create the shuffler thread */
-		shuffler_task = kthread_run(rcu_torture_shuffle, NULL,
-					  "rcu_torture_shuffle");
-		if (IS_ERR(shuffler_task)) {
-			free_cpumask_var(shuffle_tmp_mask);
-			firsterr = PTR_ERR(shuffler_task);
-			VERBOSE_PRINTK_ERRSTRING("Failed to create shuffler");
-			shuffler_task = NULL;
+		firsterr = torture_shuffle_init(shuffle_interval * HZ);
+		if (firsterr)
 			goto unwind;
-		}
 	}
 	if (stutter < 0)
 		stutter = 0;
 	if (stutter) {
-		/* Create the stutter thread */
-		stutter_task = kthread_run(rcu_torture_stutter, NULL,
-					  "rcu_torture_stutter");
-		if (IS_ERR(stutter_task)) {
-			firsterr = PTR_ERR(stutter_task);
-			VERBOSE_PRINTK_ERRSTRING("Failed to create stutter");
-			stutter_task = NULL;
+		firsterr = torture_stutter_init(stutter * HZ);
+		if (firsterr)
 			goto unwind;
-		}
 	}
 	if (fqs_duration < 0)
 		fqs_duration = 0;
 	if (fqs_duration) {
-		/* Create the stutter thread */
-		fqs_task = kthread_run(rcu_torture_fqs, NULL,
-				       "rcu_torture_fqs");
-		if (IS_ERR(fqs_task)) {
-			firsterr = PTR_ERR(fqs_task);
-			VERBOSE_PRINTK_ERRSTRING("Failed to create fqs");
-			fqs_task = NULL;
+		/* Create the fqs thread */
+		torture_create_kthread(rcu_torture_fqs, NULL, fqs_task);
+		if (firsterr)
 			goto unwind;
-		}
 	}
 	if (test_boost_interval < 1)
 		test_boost_interval = 1;
@@ -2097,49 +1549,31 @@ rcu_torture_init(void)
 		for_each_possible_cpu(i) {
 			if (cpu_is_offline(i))
 				continue;  /* Heuristic: CPU can go offline. */
-			retval = rcutorture_booster_init(i);
-			if (retval < 0) {
-				firsterr = retval;
+			firsterr = rcutorture_booster_init(i);
+			if (firsterr)
 				goto unwind;
-			}
 		}
 	}
-	if (shutdown_secs > 0) {
-		shutdown_time = jiffies + shutdown_secs * HZ;
-		shutdown_task = kthread_create(rcu_torture_shutdown, NULL,
-					       "rcu_torture_shutdown");
-		if (IS_ERR(shutdown_task)) {
-			firsterr = PTR_ERR(shutdown_task);
-			VERBOSE_PRINTK_ERRSTRING("Failed to create shutdown");
-			shutdown_task = NULL;
-			goto unwind;
-		}
-		wake_up_process(shutdown_task);
-	}
-	i = rcu_torture_onoff_init();
-	if (i != 0) {
-		firsterr = i;
+	firsterr = torture_shutdown_init(shutdown_secs, rcu_torture_cleanup);
+	if (firsterr)
 		goto unwind;
-	}
-	register_reboot_notifier(&rcutorture_shutdown_nb);
-	i = rcu_torture_stall_init();
-	if (i != 0) {
-		firsterr = i;
+	firsterr = torture_onoff_init(onoff_holdoff * HZ, onoff_interval * HZ);
+	if (firsterr)
 		goto unwind;
-	}
-	retval = rcu_torture_barrier_init();
-	if (retval != 0) {
-		firsterr = retval;
+	firsterr = rcu_torture_stall_init();
+	if (firsterr)
+		goto unwind;
+	firsterr = rcu_torture_barrier_init();
+	if (firsterr)
 		goto unwind;
-	}
 	if (object_debug)
 		rcu_test_debug_objects();
 	rcutorture_record_test_transition();
-	mutex_unlock(&fullstop_mutex);
+	torture_init_end();
 	return 0;
 
 unwind:
-	mutex_unlock(&fullstop_mutex);
+	torture_init_end();
 	rcu_torture_cleanup();
 	return firsterr;
 }
diff --git a/kernel/rcu/srcu.c b/kernel/rcu/srcu.c
index 3318d8284384..c639556f3fa0 100644
--- a/kernel/rcu/srcu.c
+++ b/kernel/rcu/srcu.c
@@ -12,8 +12,8 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
  *
  * Copyright (C) IBM Corporation, 2006
  * Copyright (C) Fujitsu, 2012
@@ -36,8 +36,6 @@
 #include <linux/delay.h>
 #include <linux/srcu.h>
 
-#include <trace/events/rcu.h>
-
 #include "rcu.h"
 
 /*
@@ -398,7 +396,7 @@ void call_srcu(struct srcu_struct *sp, struct rcu_head *head,
 	rcu_batch_queue(&sp->batch_queue, head);
 	if (!sp->running) {
 		sp->running = true;
-		schedule_delayed_work(&sp->work, 0);
+		queue_delayed_work(system_power_efficient_wq, &sp->work, 0);
 	}
 	spin_unlock_irqrestore(&sp->queue_lock, flags);
 }
@@ -674,7 +672,8 @@ static void srcu_reschedule(struct srcu_struct *sp)
 	}
 
 	if (pending)
-		schedule_delayed_work(&sp->work, SRCU_INTERVAL);
+		queue_delayed_work(system_power_efficient_wq,
+				   &sp->work, SRCU_INTERVAL);
 }
 
 /*
diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c
index 1254f312d024..d9efcc13008c 100644
--- a/kernel/rcu/tiny.c
+++ b/kernel/rcu/tiny.c
@@ -12,8 +12,8 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
  *
  * Copyright IBM Corporation, 2008
  *
@@ -37,10 +37,6 @@
 #include <linux/prefetch.h>
 #include <linux/ftrace_event.h>
 
-#ifdef CONFIG_RCU_TRACE
-#include <trace/events/rcu.h>
-#endif /* #else #ifdef CONFIG_RCU_TRACE */
-
 #include "rcu.h"
 
 /* Forward declarations for tiny_plugin.h. */
diff --git a/kernel/rcu/tiny_plugin.h b/kernel/rcu/tiny_plugin.h
index 280d06cae352..431528520562 100644
--- a/kernel/rcu/tiny_plugin.h
+++ b/kernel/rcu/tiny_plugin.h
@@ -14,8 +14,8 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
  *
  * Copyright (c) 2010 Linaro
  *
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index b3d116cd072d..0c47e300210a 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -12,8 +12,8 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
  *
  * Copyright IBM Corporation, 2008
  *
@@ -58,8 +58,6 @@
 #include <linux/suspend.h>
 
 #include "tree.h"
-#include <trace/events/rcu.h>
-
 #include "rcu.h"
 
 MODULE_ALIAS("rcutree");
@@ -837,7 +835,7 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp,
 	 * to the next.  Only do this for the primary flavor of RCU.
 	 */
 	if (rdp->rsp == rcu_state &&
-	    ULONG_CMP_GE(ACCESS_ONCE(jiffies), rdp->rsp->jiffies_resched)) {
+	    ULONG_CMP_GE(jiffies, rdp->rsp->jiffies_resched)) {
 		rdp->rsp->jiffies_resched += 5;
 		resched_cpu(rdp->cpu);
 	}
@@ -847,7 +845,7 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp,
 
 static void record_gp_stall_check_time(struct rcu_state *rsp)
 {
-	unsigned long j = ACCESS_ONCE(jiffies);
+	unsigned long j = jiffies;
 	unsigned long j1;
 
 	rsp->gp_start = j;
@@ -1005,7 +1003,7 @@ static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp)
 
 	if (rcu_cpu_stall_suppress || !rcu_gp_in_progress(rsp))
 		return;
-	j = ACCESS_ONCE(jiffies);
+	j = jiffies;
 
 	/*
 	 * Lots of memory barriers to reject false positives.
@@ -1423,13 +1421,14 @@ static int rcu_gp_init(struct rcu_state *rsp)
 
 	/* Advance to a new grace period and initialize state. */
 	record_gp_stall_check_time(rsp);
-	smp_wmb(); /* Record GP times before starting GP. */
-	rsp->gpnum++;
+	/* Record GP times before starting GP, hence smp_store_release(). */
+	smp_store_release(&rsp->gpnum, rsp->gpnum + 1);
 	trace_rcu_grace_period(rsp->name, rsp->gpnum, TPS("start"));
 	raw_spin_unlock_irq(&rnp->lock);
 
 	/* Exclude any concurrent CPU-hotplug operations. */
 	mutex_lock(&rsp->onoff_mutex);
+	smp_mb__after_unlock_lock(); /* ->gpnum increment before GP! */
 
 	/*
 	 * Set the quiescent-state-needed bits in all the rcu_node
@@ -1557,10 +1556,11 @@ static void rcu_gp_cleanup(struct rcu_state *rsp)
 	}
 	rnp = rcu_get_root(rsp);
 	raw_spin_lock_irq(&rnp->lock);
-	smp_mb__after_unlock_lock();
+	smp_mb__after_unlock_lock(); /* Order GP before ->completed update. */
 	rcu_nocb_gp_set(rnp, nocb);
 
-	rsp->completed = rsp->gpnum; /* Declare grace period done. */
+	/* Declare grace period done. */
+	ACCESS_ONCE(rsp->completed) = rsp->gpnum;
 	trace_rcu_grace_period(rsp->name, rsp->completed, TPS("end"));
 	rsp->fqs_state = RCU_GP_IDLE;
 	rdp = this_cpu_ptr(rsp->rda);
@@ -2304,7 +2304,7 @@ static void force_quiescent_state(struct rcu_state *rsp)
 		if (rnp_old != NULL)
 			raw_spin_unlock(&rnp_old->fqslock);
 		if (ret) {
-			rsp->n_force_qs_lh++;
+			ACCESS_ONCE(rsp->n_force_qs_lh)++;
 			return;
 		}
 		rnp_old = rnp;
@@ -2316,7 +2316,7 @@ static void force_quiescent_state(struct rcu_state *rsp)
 	smp_mb__after_unlock_lock();
 	raw_spin_unlock(&rnp_old->fqslock);
 	if (ACCESS_ONCE(rsp->gp_flags) & RCU_GP_FLAG_FQS) {
-		rsp->n_force_qs_lh++;
+		ACCESS_ONCE(rsp->n_force_qs_lh)++;
 		raw_spin_unlock_irqrestore(&rnp_old->lock, flags);
 		return;  /* Someone beat us to it. */
 	}
@@ -2639,6 +2639,58 @@ void synchronize_rcu_bh(void)
 }
 EXPORT_SYMBOL_GPL(synchronize_rcu_bh);
 
+/**
+ * get_state_synchronize_rcu - Snapshot current RCU state
+ *
+ * Returns a cookie that is used by a later call to cond_synchronize_rcu()
+ * to determine whether or not a full grace period has elapsed in the
+ * meantime.
+ */
+unsigned long get_state_synchronize_rcu(void)
+{
+	/*
+	 * Any prior manipulation of RCU-protected data must happen
+	 * before the load from ->gpnum.
+	 */
+	smp_mb();  /* ^^^ */
+
+	/*
+	 * Make sure this load happens before the purportedly
+	 * time-consuming work between get_state_synchronize_rcu()
+	 * and cond_synchronize_rcu().
+	 */
+	return smp_load_acquire(&rcu_state->gpnum);
+}
+EXPORT_SYMBOL_GPL(get_state_synchronize_rcu);
+
+/**
+ * cond_synchronize_rcu - Conditionally wait for an RCU grace period
+ *
+ * @oldstate: return value from earlier call to get_state_synchronize_rcu()
+ *
+ * If a full RCU grace period has elapsed since the earlier call to
+ * get_state_synchronize_rcu(), just return.  Otherwise, invoke
+ * synchronize_rcu() to wait for a full grace period.
+ *
+ * Yes, this function does not take counter wrap into account.  But
+ * counter wrap is harmless.  If the counter wraps, we have waited for
+ * more than 2 billion grace periods (and way more on a 64-bit system!),
+ * so waiting for one additional grace period should be just fine.
+ */
+void cond_synchronize_rcu(unsigned long oldstate)
+{
+	unsigned long newstate;
+
+	/*
+	 * Ensure that this load happens before any RCU-destructive
+	 * actions the caller might carry out after we return.
+	 */
+	newstate = smp_load_acquire(&rcu_state->completed);
+	if (ULONG_CMP_GE(oldstate, newstate))
+		synchronize_rcu();
+}
+EXPORT_SYMBOL_GPL(cond_synchronize_rcu);
+
 static int synchronize_sched_expedited_cpu_stop(void *data)
 {
 	/*
@@ -2880,7 +2932,7 @@ static int rcu_pending(int cpu)
  * non-NULL, store an indication of whether all callbacks are lazy.
  * (If there are no callbacks, all of them are deemed to be lazy.)
  */
-static int rcu_cpu_has_callbacks(int cpu, bool *all_lazy)
+static int __maybe_unused rcu_cpu_has_callbacks(int cpu, bool *all_lazy)
 {
 	bool al = true;
 	bool hc = false;
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index 8c19873f1ac9..75dc3c39a02a 100644
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -13,8 +13,8 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
  *
  * Copyright IBM Corporation, 2008
  *
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 6e2ef4b2b920..962d1d589929 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -14,8 +14,8 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
  *
  * Copyright Red Hat, 2009
  * Copyright IBM Corporation, 2009
@@ -1586,11 +1586,13 @@ static void rcu_prepare_kthreads(int cpu)
  * Because we not have RCU_FAST_NO_HZ, just check whether this CPU needs
  * any flavor of RCU.
  */
+#ifndef CONFIG_RCU_NOCB_CPU_ALL
 int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies)
 {
 	*delta_jiffies = ULONG_MAX;
 	return rcu_cpu_has_callbacks(cpu, NULL);
 }
+#endif /* #ifndef CONFIG_RCU_NOCB_CPU_ALL */
 
 /*
  * Because we do not have RCU_FAST_NO_HZ, don't bother cleaning up
@@ -1656,7 +1658,7 @@ extern int tick_nohz_active;
  * only if it has been awhile since the last time we did so.  Afterwards,
  * if there are any callbacks ready for immediate invocation, return true.
  */
-static bool rcu_try_advance_all_cbs(void)
+static bool __maybe_unused rcu_try_advance_all_cbs(void)
 {
 	bool cbs_ready = false;
 	struct rcu_data *rdp;
@@ -1696,6 +1698,7 @@ static bool rcu_try_advance_all_cbs(void)
  *
  * The caller must have disabled interrupts.
  */
+#ifndef CONFIG_RCU_NOCB_CPU_ALL
 int rcu_needs_cpu(int cpu, unsigned long *dj)
 {
 	struct rcu_dynticks *rdtp = &per_cpu(rcu_dynticks, cpu);
@@ -1726,6 +1729,7 @@ int rcu_needs_cpu(int cpu, unsigned long *dj)
 	}
 	return 0;
 }
+#endif /* #ifndef CONFIG_RCU_NOCB_CPU_ALL */
 
 /*
  * Prepare a CPU for idle from an RCU perspective.  The first major task
@@ -1739,6 +1743,7 @@ int rcu_needs_cpu(int cpu, unsigned long *dj)
  */
 static void rcu_prepare_for_idle(int cpu)
 {
+#ifndef CONFIG_RCU_NOCB_CPU_ALL
 	struct rcu_data *rdp;
 	struct rcu_dynticks *rdtp = &per_cpu(rcu_dynticks, cpu);
 	struct rcu_node *rnp;
@@ -1790,6 +1795,7 @@ static void rcu_prepare_for_idle(int cpu)
 		rcu_accelerate_cbs(rsp, rnp, rdp);
 		raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */
 	}
+#endif /* #ifndef CONFIG_RCU_NOCB_CPU_ALL */
 }
 
 /*
@@ -1799,11 +1805,12 @@ static void rcu_prepare_for_idle(int cpu)
  */
 static void rcu_cleanup_after_idle(int cpu)
 {
-
+#ifndef CONFIG_RCU_NOCB_CPU_ALL
 	if (rcu_is_nocb_cpu(cpu))
 		return;
 	if (rcu_try_advance_all_cbs())
 		invoke_rcu_core();
+#endif /* #ifndef CONFIG_RCU_NOCB_CPU_ALL */
 }
 
 /*
@@ -2101,6 +2108,7 @@ static void rcu_init_one_nocb(struct rcu_node *rnp)
 	init_waitqueue_head(&rnp->nocb_gp_wq[1]);
 }
 
+#ifndef CONFIG_RCU_NOCB_CPU_ALL
 /* Is the specified CPU a no-CPUs CPU? */
 bool rcu_is_nocb_cpu(int cpu)
 {
@@ -2108,6 +2116,7 @@ bool rcu_is_nocb_cpu(int cpu)
 		return cpumask_test_cpu(cpu, rcu_nocb_mask);
 	return false;
 }
+#endif /* #ifndef CONFIG_RCU_NOCB_CPU_ALL */
 
 /*
  * Enqueue the specified string of rcu_head structures onto the specified
@@ -2893,7 +2902,7 @@ static void rcu_sysidle_init_percpu_data(struct rcu_dynticks *rdtp)
  * CPU unless the grace period has extended for too long.
  *
  * This code relies on the fact that all NO_HZ_FULL CPUs are also
- * CONFIG_RCU_NOCB_CPUs.
+ * CONFIG_RCU_NOCB_CPU CPUs.
  */
 static bool rcu_nohz_full_cpu(struct rcu_state *rsp)
 {
diff --git a/kernel/rcu/tree_trace.c b/kernel/rcu/tree_trace.c
index 4def475336d4..5cdc62e1beeb 100644
--- a/kernel/rcu/tree_trace.c
+++ b/kernel/rcu/tree_trace.c
@@ -12,8 +12,8 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
  *
  * Copyright IBM Corporation, 2008
  *
@@ -273,7 +273,7 @@ static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp)
 	seq_printf(m, "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu oqlen=%ld/%ld\n",
 		   rsp->n_force_qs, rsp->n_force_qs_ngp,
 		   rsp->n_force_qs - rsp->n_force_qs_ngp,
-		   rsp->n_force_qs_lh, rsp->qlen_lazy, rsp->qlen);
+		   ACCESS_ONCE(rsp->n_force_qs_lh), rsp->qlen_lazy, rsp->qlen);
 	for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < rcu_num_nodes; rnp++) {
 		if (rnp->level != level) {
 			seq_puts(m, "\n");
diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index c54609faf233..4c0a9b0af469 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -12,8 +12,8 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
  *
  * Copyright IBM Corporation, 2001
  *
@@ -49,7 +49,6 @@
 #include <linux/module.h>
 
 #define CREATE_TRACE_POINTS
-#include <trace/events/rcu.h>
 
 #include "rcu.h"
 
diff --git a/kernel/relay.c b/kernel/relay.c
index 5001c9887db1..5a56d3c8dc03 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -227,7 +227,7 @@ static void relay_destroy_buf(struct rchan_buf *buf)
  *	relay_remove_buf - remove a channel buffer
  *	@kref: target kernel reference that contains the relay buffer
  *
- *	Removes the file from the fileystem, which also frees the
+ *	Removes the file from the filesystem, which also frees the
  *	rchan_buf_struct and the channel buffer.  Should only be called from
  *	kref_put().
  */
@@ -1195,8 +1195,6 @@ static void relay_pipe_buf_release(struct pipe_inode_info *pipe,
 
 static const struct pipe_buf_operations relay_pipe_buf_ops = {
 	.can_merge = 0,
-	.map = generic_pipe_buf_map,
-	.unmap = generic_pipe_buf_unmap,
 	.confirm = generic_pipe_buf_confirm,
 	.release = relay_pipe_buf_release,
 	.steal = generic_pipe_buf_steal,
@@ -1253,7 +1251,7 @@ static ssize_t subbuf_splice_actor(struct file *in,
 	subbuf_pages = rbuf->chan->alloc_size >> PAGE_SHIFT;
 	pidx = (read_start / PAGE_SIZE) % subbuf_pages;
 	poff = read_start & ~PAGE_MASK;
-	nr_pages = min_t(unsigned int, subbuf_pages, pipe->buffers);
+	nr_pages = min_t(unsigned int, subbuf_pages, spd.nr_pages_max);
 
 	for (total_len = 0; spd.nr_pages < nr_pages; spd.nr_pages++) {
 		unsigned int this_len, this_end, private;
diff --git a/kernel/res_counter.c b/kernel/res_counter.c
index 4aa8a305aede..51dbac6a3633 100644
--- a/kernel/res_counter.c
+++ b/kernel/res_counter.c
@@ -22,8 +22,18 @@ void res_counter_init(struct res_counter *counter, struct res_counter *parent)
 	counter->parent = parent;
 }
 
-int res_counter_charge_locked(struct res_counter *counter, unsigned long val,
-			      bool force)
+static u64 res_counter_uncharge_locked(struct res_counter *counter,
+				       unsigned long val)
+{
+	if (WARN_ON(counter->usage < val))
+		val = counter->usage;
+
+	counter->usage -= val;
+	return counter->usage;
+}
+
+static int res_counter_charge_locked(struct res_counter *counter,
+				     unsigned long val, bool force)
 {
 	int ret = 0;
 
@@ -86,15 +96,6 @@ int res_counter_charge_nofail(struct res_counter *counter, unsigned long val,
 	return __res_counter_charge(counter, val, limit_fail_at, true);
 }
 
-u64 res_counter_uncharge_locked(struct res_counter *counter, unsigned long val)
-{
-	if (WARN_ON(counter->usage < val))
-		val = counter->usage;
-
-	counter->usage -= val;
-	return counter->usage;
-}
-
 u64 res_counter_uncharge_until(struct res_counter *counter,
 			       struct res_counter *top,
 			       unsigned long val)
diff --git a/kernel/resource.c b/kernel/resource.c
index 3f285dce9347..8957d686e29b 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -432,11 +432,6 @@ static void resource_clip(struct resource *res, resource_size_t min,
 		res->end = max;
 }
 
-static bool resource_contains(struct resource *res1, struct resource *res2)
-{
-	return res1->start <= res2->start && res1->end >= res2->end;
-}
-
 /*
  * Find empty slot in the resource tree with the given range and
  * alignment constraints
@@ -471,10 +466,11 @@ static int __find_resource(struct resource *root, struct resource *old,
 		arch_remove_reservations(&tmp);
 
 		/* Check for overflow after ALIGN() */
-		avail = *new;
 		avail.start = ALIGN(tmp.start, constraint->align);
 		avail.end = tmp.end;
+		avail.flags = new->flags & ~IORESOURCE_UNSET;
 		if (avail.start >= tmp.start) {
+			alloc.flags = avail.flags;
 			alloc.start = constraint->alignf(constraint->alignf_data, &avail,
 					size, constraint->align);
 			alloc.end = alloc.start + size - 1;
@@ -515,7 +511,7 @@ static int find_resource(struct resource *root, struct resource *new,
  * @newsize: new size of the resource descriptor
  * @constraint: the size and alignment constraints to be met.
  */
-int reallocate_resource(struct resource *root, struct resource *old,
+static int reallocate_resource(struct resource *root, struct resource *old,
 			resource_size_t newsize,
 			struct resource_constraint  *constraint)
 {
@@ -949,8 +945,8 @@ struct resource * __request_region(struct resource *parent,
 	res->name = name;
 	res->start = start;
 	res->end = start + n - 1;
-	res->flags = IORESOURCE_BUSY;
-	res->flags |= flags;
+	res->flags = resource_type(parent);
+	res->flags |= IORESOURCE_BUSY | flags;
 
 	write_lock(&resource_lock);
 
diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile
index 9a95c8c2af2a..ab32b7b0db5c 100644
--- a/kernel/sched/Makefile
+++ b/kernel/sched/Makefile
@@ -13,7 +13,7 @@ endif
 
 obj-y += core.o proc.o clock.o cputime.o
 obj-y += idle_task.o fair.o rt.o deadline.o stop_task.o
-obj-y += wait.o completion.o
+obj-y += wait.o completion.o idle.o
 obj-$(CONFIG_SMP) += cpupri.o cpudeadline.o
 obj-$(CONFIG_SCHED_AUTOGROUP) += auto_group.o
 obj-$(CONFIG_SCHEDSTATS) += stats.o
diff --git a/kernel/sched/auto_group.c b/kernel/sched/auto_group.c
index 4a073539c58e..e73efba98301 100644
--- a/kernel/sched/auto_group.c
+++ b/kernel/sched/auto_group.c
@@ -203,7 +203,7 @@ int proc_sched_autogroup_set_nice(struct task_struct *p, int nice)
 	struct autogroup *ag;
 	int err;
 
-	if (nice < -20 || nice > 19)
+	if (nice < MIN_NICE || nice > MAX_NICE)
 		return -EINVAL;
 
 	err = security_task_setnice(current, nice);
diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
index b30a2924ef14..3ef6451e972e 100644
--- a/kernel/sched/clock.c
+++ b/kernel/sched/clock.c
@@ -60,13 +60,14 @@
 #include <linux/sched.h>
 #include <linux/static_key.h>
 #include <linux/workqueue.h>
+#include <linux/compiler.h>
 
 /*
  * Scheduler clock - returns current time in nanosec units.
  * This is default implementation.
  * Architectures and sub-architectures can override this.
  */
-unsigned long long __attribute__((weak)) sched_clock(void)
+unsigned long long __weak sched_clock(void)
 {
 	return (unsigned long long)(jiffies - INITIAL_JIFFIES)
 					* (NSEC_PER_SEC / HZ);
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index f5c6635b806c..084d17f89139 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -73,6 +73,7 @@
 #include <linux/init_task.h>
 #include <linux/binfmts.h>
 #include <linux/context_tracking.h>
+#include <linux/compiler.h>
 
 #include <asm/switch_to.h>
 #include <asm/tlb.h>
@@ -432,7 +433,7 @@ void hrtick_start(struct rq *rq, u64 delay)
 	if (rq == this_rq()) {
 		__hrtick_restart(rq);
 	} else if (!rq->hrtick_csd_pending) {
-		__smp_call_function_single(cpu_of(rq), &rq->hrtick_csd, 0);
+		smp_call_function_single_async(cpu_of(rq), &rq->hrtick_csd);
 		rq->hrtick_csd_pending = 1;
 	}
 }
@@ -555,12 +556,15 @@ void resched_cpu(int cpu)
  * selecting an idle cpu will add more delays to the timers than intended
  * (as that cpu's timer base may not be uptodate wrt jiffies etc).
  */
-int get_nohz_timer_target(void)
+int get_nohz_timer_target(int pinned)
 {
 	int cpu = smp_processor_id();
 	int i;
 	struct sched_domain *sd;
 
+	if (pinned || !get_sysctl_timer_migration() || !idle_cpu(cpu))
+		return cpu;
+
 	rcu_read_lock();
 	for_each_domain(cpu, sd) {
 		for_each_cpu(i, sched_domain_span(sd)) {
@@ -823,19 +827,13 @@ static void update_rq_clock_task(struct rq *rq, s64 delta)
 #endif
 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
 	if (static_key_false((&paravirt_steal_rq_enabled))) {
-		u64 st;
-
 		steal = paravirt_steal_clock(cpu_of(rq));
 		steal -= rq->prev_steal_time_rq;
 
 		if (unlikely(steal > delta))
 			steal = delta;
 
-		st = steal_ticks(steal);
-		steal = st * TICK_NSEC;
-
 		rq->prev_steal_time_rq += steal;
-
 		delta -= steal;
 	}
 #endif
@@ -1745,8 +1743,10 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p)
 	p->numa_scan_seq = p->mm ? p->mm->numa_scan_seq : 0;
 	p->numa_scan_period = sysctl_numa_balancing_scan_delay;
 	p->numa_work.next = &p->numa_work;
-	p->numa_faults = NULL;
-	p->numa_faults_buffer = NULL;
+	p->numa_faults_memory = NULL;
+	p->numa_faults_buffer_memory = NULL;
+	p->last_task_numa_placement = 0;
+	p->last_sum_exec_runtime = 0;
 
 	INIT_LIST_HEAD(&p->numa_entry);
 	p->numa_group = NULL;
@@ -2149,8 +2149,6 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev)
 	if (mm)
 		mmdrop(mm);
 	if (unlikely(prev_state == TASK_DEAD)) {
-		task_numa_free(prev);
-
 		if (prev->sched_class->task_dead)
 			prev->sched_class->task_dead(prev);
 
@@ -2167,13 +2165,6 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev)
 
 #ifdef CONFIG_SMP
 
-/* assumes rq->lock is held */
-static inline void pre_schedule(struct rq *rq, struct task_struct *prev)
-{
-	if (prev->sched_class->pre_schedule)
-		prev->sched_class->pre_schedule(rq, prev);
-}
-
 /* rq->lock is NOT held, but preemption is disabled */
 static inline void post_schedule(struct rq *rq)
 {
@@ -2191,10 +2182,6 @@ static inline void post_schedule(struct rq *rq)
 
 #else
 
-static inline void pre_schedule(struct rq *rq, struct task_struct *p)
-{
-}
-
 static inline void post_schedule(struct rq *rq)
 {
 }
@@ -2205,7 +2192,7 @@ static inline void post_schedule(struct rq *rq)
  * schedule_tail - first thing a freshly forked thread must call.
  * @prev: the thread we just switched away from.
  */
-asmlinkage void schedule_tail(struct task_struct *prev)
+asmlinkage __visible void schedule_tail(struct task_struct *prev)
 	__releases(rq->lock)
 {
 	struct rq *rq = this_rq();
@@ -2510,8 +2497,13 @@ void __kprobes preempt_count_add(int val)
 	DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >=
 				PREEMPT_MASK - 10);
 #endif
-	if (preempt_count() == val)
-		trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
+	if (preempt_count() == val) {
+		unsigned long ip = get_parent_ip(CALLER_ADDR1);
+#ifdef CONFIG_DEBUG_PREEMPT
+		current->preempt_disable_ip = ip;
+#endif
+		trace_preempt_off(CALLER_ADDR0, ip);
+	}
 }
 EXPORT_SYMBOL(preempt_count_add);
 
@@ -2554,6 +2546,13 @@ static noinline void __schedule_bug(struct task_struct *prev)
 	print_modules();
 	if (irqs_disabled())
 		print_irqtrace_events(prev);
+#ifdef CONFIG_DEBUG_PREEMPT
+	if (in_atomic_preempt_off()) {
+		pr_err("Preemption disabled at:");
+		print_ip_sym(current->preempt_disable_ip);
+		pr_cont("\n");
+	}
+#endif
 	dump_stack();
 	add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
 }
@@ -2577,36 +2576,40 @@ static inline void schedule_debug(struct task_struct *prev)
 	schedstat_inc(this_rq(), sched_count);
 }
 
-static void put_prev_task(struct rq *rq, struct task_struct *prev)
-{
-	if (prev->on_rq || rq->skip_clock_update < 0)
-		update_rq_clock(rq);
-	prev->sched_class->put_prev_task(rq, prev);
-}
-
 /*
  * Pick up the highest-prio task:
  */
 static inline struct task_struct *
-pick_next_task(struct rq *rq)
+pick_next_task(struct rq *rq, struct task_struct *prev)
 {
-	const struct sched_class *class;
+	const struct sched_class *class = &fair_sched_class;
 	struct task_struct *p;
 
 	/*
 	 * Optimization: we know that if all tasks are in
 	 * the fair class we can call that function directly:
 	 */
-	if (likely(rq->nr_running == rq->cfs.h_nr_running)) {
-		p = fair_sched_class.pick_next_task(rq);
-		if (likely(p))
-			return p;
+	if (likely(prev->sched_class == class &&
+		   rq->nr_running == rq->cfs.h_nr_running)) {
+		p = fair_sched_class.pick_next_task(rq, prev);
+		if (unlikely(p == RETRY_TASK))
+			goto again;
+
+		/* assumes fair_sched_class->next == idle_sched_class */
+		if (unlikely(!p))
+			p = idle_sched_class.pick_next_task(rq, prev);
+
+		return p;
 	}
 
+again:
 	for_each_class(class) {
-		p = class->pick_next_task(rq);
-		if (p)
+		p = class->pick_next_task(rq, prev);
+		if (p) {
+			if (unlikely(p == RETRY_TASK))
+				goto again;
 			return p;
+		}
 	}
 
 	BUG(); /* the idle class will always have a runnable task */
@@ -2700,13 +2703,10 @@ need_resched:
 		switch_count = &prev->nvcsw;
 	}
 
-	pre_schedule(rq, prev);
-
-	if (unlikely(!rq->nr_running))
-		idle_balance(cpu, rq);
+	if (prev->on_rq || rq->skip_clock_update < 0)
+		update_rq_clock(rq);
 
-	put_prev_task(rq, prev);
-	next = pick_next_task(rq);
+	next = pick_next_task(rq, prev);
 	clear_tsk_need_resched(prev);
 	clear_preempt_need_resched();
 	rq->skip_clock_update = 0;
@@ -2747,7 +2747,7 @@ static inline void sched_submit_work(struct task_struct *tsk)
 		blk_schedule_flush_plug(tsk);
 }
 
-asmlinkage void __sched schedule(void)
+asmlinkage __visible void __sched schedule(void)
 {
 	struct task_struct *tsk = current;
 
@@ -2757,7 +2757,7 @@ asmlinkage void __sched schedule(void)
 EXPORT_SYMBOL(schedule);
 
 #ifdef CONFIG_CONTEXT_TRACKING
-asmlinkage void __sched schedule_user(void)
+asmlinkage __visible void __sched schedule_user(void)
 {
 	/*
 	 * If we come here after a random call to set_need_resched(),
@@ -2789,7 +2789,7 @@ void __sched schedule_preempt_disabled(void)
  * off of preempt_enable. Kernel preemptions off return from interrupt
  * occur there and call schedule directly.
  */
-asmlinkage void __sched notrace preempt_schedule(void)
+asmlinkage __visible void __sched notrace preempt_schedule(void)
 {
 	/*
 	 * If there is a non-zero preempt_count or interrupts are disabled,
@@ -2819,7 +2819,7 @@ EXPORT_SYMBOL(preempt_schedule);
  * Note, that this is called and return with irqs disabled. This will
  * protect us against recursive calling from irq.
  */
-asmlinkage void __sched preempt_schedule_irq(void)
+asmlinkage __visible void __sched preempt_schedule_irq(void)
 {
 	enum ctx_state prev_state;
 
@@ -2852,52 +2852,6 @@ int default_wake_function(wait_queue_t *curr, unsigned mode, int wake_flags,
 }
 EXPORT_SYMBOL(default_wake_function);
 
-static long __sched
-sleep_on_common(wait_queue_head_t *q, int state, long timeout)
-{
-	unsigned long flags;
-	wait_queue_t wait;
-
-	init_waitqueue_entry(&wait, current);
-
-	__set_current_state(state);
-
-	spin_lock_irqsave(&q->lock, flags);
-	__add_wait_queue(q, &wait);
-	spin_unlock(&q->lock);
-	timeout = schedule_timeout(timeout);
-	spin_lock_irq(&q->lock);
-	__remove_wait_queue(q, &wait);
-	spin_unlock_irqrestore(&q->lock, flags);
-
-	return timeout;
-}
-
-void __sched interruptible_sleep_on(wait_queue_head_t *q)
-{
-	sleep_on_common(q, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
-}
-EXPORT_SYMBOL(interruptible_sleep_on);
-
-long __sched
-interruptible_sleep_on_timeout(wait_queue_head_t *q, long timeout)
-{
-	return sleep_on_common(q, TASK_INTERRUPTIBLE, timeout);
-}
-EXPORT_SYMBOL(interruptible_sleep_on_timeout);
-
-void __sched sleep_on(wait_queue_head_t *q)
-{
-	sleep_on_common(q, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
-}
-EXPORT_SYMBOL(sleep_on);
-
-long __sched sleep_on_timeout(wait_queue_head_t *q, long timeout)
-{
-	return sleep_on_common(q, TASK_UNINTERRUPTIBLE, timeout);
-}
-EXPORT_SYMBOL(sleep_on_timeout);
-
 #ifdef CONFIG_RT_MUTEXES
 
 /*
@@ -2908,7 +2862,8 @@ EXPORT_SYMBOL(sleep_on_timeout);
  * This function changes the 'effective' priority of a task. It does
  * not touch ->normal_prio like __setscheduler().
  *
- * Used by the rt_mutex code to implement priority inheritance logic.
+ * Used by the rt_mutex code to implement priority inheritance
+ * logic. Call site only calls if the priority of the task changed.
  */
 void rt_mutex_setprio(struct task_struct *p, int prio)
 {
@@ -2998,7 +2953,7 @@ void set_user_nice(struct task_struct *p, long nice)
 	unsigned long flags;
 	struct rq *rq;
 
-	if (TASK_NICE(p) == nice || nice < -20 || nice > 19)
+	if (task_nice(p) == nice || nice < MIN_NICE || nice > MAX_NICE)
 		return;
 	/*
 	 * We have to be careful, if called from sys_setpriority(),
@@ -3076,11 +3031,11 @@ SYSCALL_DEFINE1(nice, int, increment)
 	if (increment > 40)
 		increment = 40;
 
-	nice = TASK_NICE(current) + increment;
-	if (nice < -20)
-		nice = -20;
-	if (nice > 19)
-		nice = 19;
+	nice = task_nice(current) + increment;
+	if (nice < MIN_NICE)
+		nice = MIN_NICE;
+	if (nice > MAX_NICE)
+		nice = MAX_NICE;
 
 	if (increment < 0 && !can_nice(current, nice))
 		return -EPERM;
@@ -3109,18 +3064,6 @@ int task_prio(const struct task_struct *p)
 }
 
 /**
- * task_nice - return the nice value of a given task.
- * @p: the task in question.
- *
- * Return: The nice value [ -20 ... 0 ... 19 ].
- */
-int task_nice(const struct task_struct *p)
-{
-	return TASK_NICE(p);
-}
-EXPORT_SYMBOL(task_nice);
-
-/**
  * idle_cpu - is a given cpu idle currently?
  * @cpu: the processor in question.
  *
@@ -3187,11 +3130,11 @@ __setparam_dl(struct task_struct *p, const struct sched_attr *attr)
 	dl_se->dl_bw = to_ratio(dl_se->dl_period, dl_se->dl_runtime);
 	dl_se->dl_throttled = 0;
 	dl_se->dl_new = 1;
+	dl_se->dl_yielded = 0;
 }
 
-/* Actually do priority change: must hold pi & rq lock. */
-static void __setscheduler(struct rq *rq, struct task_struct *p,
-			   const struct sched_attr *attr)
+static void __setscheduler_params(struct task_struct *p,
+		const struct sched_attr *attr)
 {
 	int policy = attr->sched_policy;
 
@@ -3211,9 +3154,21 @@ static void __setscheduler(struct rq *rq, struct task_struct *p,
 	 * getparam()/getattr() don't report silly values for !rt tasks.
 	 */
 	p->rt_priority = attr->sched_priority;
-
 	p->normal_prio = normal_prio(p);
-	p->prio = rt_mutex_getprio(p);
+	set_load_weight(p);
+}
+
+/* Actually do priority change: must hold pi & rq lock. */
+static void __setscheduler(struct rq *rq, struct task_struct *p,
+			   const struct sched_attr *attr)
+{
+	__setscheduler_params(p, attr);
+
+	/*
+	 * If we get here, there was no pi waiters boosting the
+	 * task. It is safe to use the normal prio.
+	 */
+	p->prio = normal_prio(p);
 
 	if (dl_prio(p->prio))
 		p->sched_class = &dl_sched_class;
@@ -3221,8 +3176,6 @@ static void __setscheduler(struct rq *rq, struct task_struct *p,
 		p->sched_class = &rt_sched_class;
 	else
 		p->sched_class = &fair_sched_class;
-
-	set_load_weight(p);
 }
 
 static void
@@ -3242,17 +3195,40 @@ __getparam_dl(struct task_struct *p, struct sched_attr *attr)
  * We ask for the deadline not being zero, and greater or equal
  * than the runtime, as well as the period of being zero or
  * greater than deadline. Furthermore, we have to be sure that
- * user parameters are above the internal resolution (1us); we
- * check sched_runtime only since it is always the smaller one.
+ * user parameters are above the internal resolution of 1us (we
+ * check sched_runtime only since it is always the smaller one) and
+ * below 2^63 ns (we have to check both sched_deadline and
+ * sched_period, as the latter can be zero).
  */
 static bool
 __checkparam_dl(const struct sched_attr *attr)
 {
-	return attr && attr->sched_deadline != 0 &&
-		(attr->sched_period == 0 ||
-		(s64)(attr->sched_period   - attr->sched_deadline) >= 0) &&
-		(s64)(attr->sched_deadline - attr->sched_runtime ) >= 0  &&
-		attr->sched_runtime >= (2 << (DL_SCALE - 1));
+	/* deadline != 0 */
+	if (attr->sched_deadline == 0)
+		return false;
+
+	/*
+	 * Since we truncate DL_SCALE bits, make sure we're at least
+	 * that big.
+	 */
+	if (attr->sched_runtime < (1ULL << DL_SCALE))
+		return false;
+
+	/*
+	 * Since we use the MSB for wrap-around and sign issues, make
+	 * sure it's not set (mind that period can be equal to zero).
+	 */
+	if (attr->sched_deadline & (1ULL << 63) ||
+	    attr->sched_period & (1ULL << 63))
+		return false;
+
+	/* runtime <= deadline <= period (if period != 0) */
+	if ((attr->sched_period != 0 &&
+	     attr->sched_period < attr->sched_deadline) ||
+	    attr->sched_deadline < attr->sched_runtime)
+		return false;
+
+	return true;
 }
 
 /*
@@ -3275,6 +3251,8 @@ static int __sched_setscheduler(struct task_struct *p,
 				const struct sched_attr *attr,
 				bool user)
 {
+	int newprio = dl_policy(attr->sched_policy) ? MAX_DL_PRIO - 1 :
+		      MAX_RT_PRIO - 1 - attr->sched_priority;
 	int retval, oldprio, oldpolicy = -1, on_rq, running;
 	int policy = attr->sched_policy;
 	unsigned long flags;
@@ -3319,7 +3297,7 @@ recheck:
 	 */
 	if (user && !capable(CAP_SYS_NICE)) {
 		if (fair_policy(policy)) {
-			if (attr->sched_nice < TASK_NICE(p) &&
+			if (attr->sched_nice < task_nice(p) &&
 			    !can_nice(p, attr->sched_nice))
 				return -EPERM;
 		}
@@ -3352,7 +3330,7 @@ recheck:
 		 * SCHED_NORMAL if the RLIMIT_NICE would normally permit it.
 		 */
 		if (p->policy == SCHED_IDLE && policy != SCHED_IDLE) {
-			if (!can_nice(p, TASK_NICE(p)))
+			if (!can_nice(p, task_nice(p)))
 				return -EPERM;
 		}
 
@@ -3389,16 +3367,18 @@ recheck:
 	}
 
 	/*
-	 * If not changing anything there's no need to proceed further:
+	 * If not changing anything there's no need to proceed further,
+	 * but store a possible modification of reset_on_fork.
 	 */
 	if (unlikely(policy == p->policy)) {
-		if (fair_policy(policy) && attr->sched_nice != TASK_NICE(p))
+		if (fair_policy(policy) && attr->sched_nice != task_nice(p))
 			goto change;
 		if (rt_policy(policy) && attr->sched_priority != p->rt_priority)
 			goto change;
 		if (dl_policy(policy))
 			goto change;
 
+		p->sched_reset_on_fork = reset_on_fork;
 		task_rq_unlock(rq, p, &flags);
 		return 0;
 	}
@@ -3452,6 +3432,24 @@ change:
 		return -EBUSY;
 	}
 
+	p->sched_reset_on_fork = reset_on_fork;
+	oldprio = p->prio;
+
+	/*
+	 * Special case for priority boosted tasks.
+	 *
+	 * If the new priority is lower or equal (user space view)
+	 * than the current (boosted) priority, we just store the new
+	 * normal parameters and do not touch the scheduler class and
+	 * the runqueue. This will be done when the task deboost
+	 * itself.
+	 */
+	if (rt_mutex_check_prio(p, newprio)) {
+		__setscheduler_params(p, attr);
+		task_rq_unlock(rq, p, &flags);
+		return 0;
+	}
+
 	on_rq = p->on_rq;
 	running = task_current(rq, p);
 	if (on_rq)
@@ -3459,16 +3457,18 @@ change:
 	if (running)
 		p->sched_class->put_prev_task(rq, p);
 
-	p->sched_reset_on_fork = reset_on_fork;
-
-	oldprio = p->prio;
 	prev_class = p->sched_class;
 	__setscheduler(rq, p, attr);
 
 	if (running)
 		p->sched_class->set_curr_task(rq);
-	if (on_rq)
-		enqueue_task(rq, p, 0);
+	if (on_rq) {
+		/*
+		 * We enqueue to tail when the priority of a task is
+		 * increased (user space view).
+		 */
+		enqueue_task(rq, p, oldprio <= p->prio ? ENQUEUE_HEAD : 0);
+	}
 
 	check_class_changed(rq, p, prev_class, oldprio);
 	task_rq_unlock(rq, p, &flags);
@@ -3624,7 +3624,7 @@ static int sched_copy_attr(struct sched_attr __user *uattr,
 	 * XXX: do we want to be lenient like existing syscalls; or do we want
 	 * to be strict and return an error on out-of-bounds values?
 	 */
-	attr->sched_nice = clamp(attr->sched_nice, -20, 19);
+	attr->sched_nice = clamp(attr->sched_nice, MIN_NICE, MAX_NICE);
 
 out:
 	return ret;
@@ -3669,6 +3669,7 @@ SYSCALL_DEFINE2(sched_setparam, pid_t, pid, struct sched_param __user *, param)
  * sys_sched_setattr - same as above, but with extended sched_attr
  * @pid: the pid in question.
  * @uattr: structure containing the extended parameters.
+ * @flags: for future extension.
  */
 SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr,
 			       unsigned int, flags)
@@ -3680,8 +3681,12 @@ SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr,
 	if (!uattr || pid < 0 || flags)
 		return -EINVAL;
 
-	if (sched_copy_attr(uattr, &attr))
-		return -EFAULT;
+	retval = sched_copy_attr(uattr, &attr);
+	if (retval)
+		return retval;
+
+	if ((int)attr.sched_policy < 0)
+		return -EINVAL;
 
 	rcu_read_lock();
 	retval = -ESRCH;
@@ -3731,7 +3736,7 @@ SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid)
  */
 SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
 {
-	struct sched_param lp;
+	struct sched_param lp = { .sched_priority = 0 };
 	struct task_struct *p;
 	int retval;
 
@@ -3748,11 +3753,8 @@ SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
 	if (retval)
 		goto out_unlock;
 
-	if (task_has_dl_policy(p)) {
-		retval = -EINVAL;
-		goto out_unlock;
-	}
-	lp.sched_priority = p->rt_priority;
+	if (task_has_rt_policy(p))
+		lp.sched_priority = p->rt_priority;
 	rcu_read_unlock();
 
 	/*
@@ -3813,6 +3815,7 @@ err_size:
  * @pid: the pid in question.
  * @uattr: structure containing the extended parameters.
  * @size: sizeof(attr) for fwd/bwd comp.
+ * @flags: for future extension.
  */
 SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr,
 		unsigned int, size, unsigned int, flags)
@@ -3845,7 +3848,7 @@ SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr,
 	else if (task_has_rt_policy(p))
 		attr.sched_priority = p->rt_priority;
 	else
-		attr.sched_nice = TASK_NICE(p);
+		attr.sched_nice = task_nice(p);
 
 	rcu_read_unlock();
 
@@ -4483,6 +4486,7 @@ void init_idle(struct task_struct *idle, int cpu)
 	rcu_read_unlock();
 
 	rq->curr = rq->idle = idle;
+	idle->on_rq = 1;
 #if defined(CONFIG_SMP)
 	idle->on_cpu = 1;
 #endif
@@ -4702,8 +4706,10 @@ void idle_task_exit(void)
 
 	BUG_ON(cpu_online(smp_processor_id()));
 
-	if (mm != &init_mm)
+	if (mm != &init_mm) {
 		switch_mm(mm, &init_mm, current);
+		finish_arch_post_lock_switch();
+	}
 	mmdrop(mm);
 }
 
@@ -4721,6 +4727,22 @@ static void calc_load_migrate(struct rq *rq)
 		atomic_long_add(delta, &calc_load_tasks);
 }
 
+static void put_prev_task_fake(struct rq *rq, struct task_struct *prev)
+{
+}
+
+static const struct sched_class fake_sched_class = {
+	.put_prev_task = put_prev_task_fake,
+};
+
+static struct task_struct fake_task = {
+	/*
+	 * Avoid pull_{rt,dl}_task()
+	 */
+	.prio = MAX_PRIO + 1,
+	.sched_class = &fake_sched_class,
+};
+
 /*
  * Migrate all tasks from the rq, sleeping tasks will be migrated by
  * try_to_wake_up()->select_task_rq().
@@ -4761,7 +4783,7 @@ static void migrate_tasks(unsigned int dead_cpu)
 		if (rq->nr_running == 1)
 			break;
 
-		next = pick_next_task(rq);
+		next = pick_next_task(rq, &fake_task);
 		BUG_ON(!next);
 		next->sched_class->put_prev_task(rq, next);
 
@@ -4851,7 +4873,7 @@ set_table_entry(struct ctl_table *entry,
 static struct ctl_table *
 sd_alloc_ctl_domain_table(struct sched_domain *sd)
 {
-	struct ctl_table *table = sd_alloc_ctl_entry(13);
+	struct ctl_table *table = sd_alloc_ctl_entry(14);
 
 	if (table == NULL)
 		return NULL;
@@ -4879,9 +4901,12 @@ sd_alloc_ctl_domain_table(struct sched_domain *sd)
 		sizeof(int), 0644, proc_dointvec_minmax, false);
 	set_table_entry(&table[10], "flags", &sd->flags,
 		sizeof(int), 0644, proc_dointvec_minmax, false);
-	set_table_entry(&table[11], "name", sd->name,
+	set_table_entry(&table[11], "max_newidle_lb_cost",
+		&sd->max_newidle_lb_cost,
+		sizeof(long), 0644, proc_doulongvec_minmax, false);
+	set_table_entry(&table[12], "name", sd->name,
 		CORENAME_MAX_SIZE, 0444, proc_dostring, false);
-	/* &table[12] is terminator */
+	/* &table[13] is terminator */
 
 	return table;
 }
@@ -5051,7 +5076,6 @@ static int sched_cpu_active(struct notifier_block *nfb,
 				      unsigned long action, void *hcpu)
 {
 	switch (action & ~CPU_TASKS_FROZEN) {
-	case CPU_STARTING:
 	case CPU_DOWN_FAILED:
 		set_cpu_active((long)hcpu, true);
 		return NOTIFY_OK;
@@ -6025,6 +6049,8 @@ sd_numa_init(struct sched_domain_topology_level *tl, int cpu)
 					,
 		.last_balance		= jiffies,
 		.balance_interval	= sd_weight,
+		.max_newidle_lb_cost	= 0,
+		.next_decay_max_lb_cost	= jiffies,
 	};
 	SD_INIT_NAME(sd, NUMA);
 	sd->private = &tl->data;
@@ -6461,7 +6487,7 @@ static cpumask_var_t fallback_doms;
  * cpu core maps. It is supposed to return 1 if the topology changed
  * or 0 if it stayed the same.
  */
-int __attribute__((weak)) arch_update_cpu_topology(void)
+int __weak arch_update_cpu_topology(void)
 {
 	return 0;
 }
@@ -6858,7 +6884,6 @@ void __init sched_init(void)
 
 		rq->rt.rt_runtime = def_rt_bandwidth.rt_runtime;
 #ifdef CONFIG_RT_GROUP_SCHED
-		INIT_LIST_HEAD(&rq->leaf_rt_rq_list);
 		init_tg_rt_entry(&root_task_group, &rq->rt, NULL, i, NULL);
 #endif
 
@@ -6947,7 +6972,8 @@ void __might_sleep(const char *file, int line, int preempt_offset)
 	static unsigned long prev_jiffy;	/* ratelimiting */
 
 	rcu_sleep_check(); /* WARN_ON_ONCE() by default, no rate limit reqd. */
-	if ((preempt_count_equals(preempt_offset) && !irqs_disabled()) ||
+	if ((preempt_count_equals(preempt_offset) && !irqs_disabled() &&
+	     !is_idle_task(current)) ||
 	    system_state != SYSTEM_RUNNING || oops_in_progress)
 		return;
 	if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
@@ -6965,6 +6991,13 @@ void __might_sleep(const char *file, int line, int preempt_offset)
 	debug_show_held_locks(current);
 	if (irqs_disabled())
 		print_irqtrace_events(current);
+#ifdef CONFIG_DEBUG_PREEMPT
+	if (!preempt_count_equals(preempt_offset)) {
+		pr_err("Preemption disabled at:");
+		print_ip_sym(current->preempt_disable_ip);
+		pr_cont("\n");
+	}
+#endif
 	dump_stack();
 }
 EXPORT_SYMBOL(__might_sleep);
@@ -7018,7 +7051,7 @@ void normalize_rt_tasks(void)
 			 * Renice negative nice level userspace
 			 * tasks back to 0:
 			 */
-			if (TASK_NICE(p) < 0 && p->mm)
+			if (task_nice(p) < 0 && p->mm)
 				set_user_nice(p, 0);
 			continue;
 		}
@@ -7186,7 +7219,7 @@ void sched_move_task(struct task_struct *tsk)
 	if (unlikely(running))
 		tsk->sched_class->put_prev_task(rq, tsk);
 
-	tg = container_of(task_css_check(tsk, cpu_cgroup_subsys_id,
+	tg = container_of(task_css_check(tsk, cpu_cgrp_id,
 				lockdep_is_held(&tsk->sighand->siglock)),
 			  struct task_group, css);
 	tg = autogroup_task_group(tsk, tg);
@@ -7613,7 +7646,7 @@ static int cpu_cgroup_can_attach(struct cgroup_subsys_state *css,
 {
 	struct task_struct *task;
 
-	cgroup_taskset_for_each(task, css, tset) {
+	cgroup_taskset_for_each(task, tset) {
 #ifdef CONFIG_RT_GROUP_SCHED
 		if (!sched_rt_can_attach(css_tg(css), task))
 			return -EINVAL;
@@ -7631,7 +7664,7 @@ static void cpu_cgroup_attach(struct cgroup_subsys_state *css,
 {
 	struct task_struct *task;
 
-	cgroup_taskset_for_each(task, css, tset)
+	cgroup_taskset_for_each(task, tset)
 		sched_move_task(task);
 }
 
@@ -7718,8 +7751,7 @@ static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota)
 	/* restart the period timer (if active) to handle new period expiry */
 	if (runtime_enabled && cfs_b->timer_active) {
 		/* force a reprogram */
-		cfs_b->timer_active = 0;
-		__start_cfs_bandwidth(cfs_b);
+		__start_cfs_bandwidth(cfs_b, true);
 	}
 	raw_spin_unlock_irq(&cfs_b->lock);
 
@@ -7970,8 +8002,7 @@ static struct cftype cpu_files[] = {
 	{ }	/* terminate */
 };
 
-struct cgroup_subsys cpu_cgroup_subsys = {
-	.name		= "cpu",
+struct cgroup_subsys cpu_cgrp_subsys = {
 	.css_alloc	= cpu_cgroup_css_alloc,
 	.css_free	= cpu_cgroup_css_free,
 	.css_online	= cpu_cgroup_css_online,
@@ -7979,7 +8010,6 @@ struct cgroup_subsys cpu_cgroup_subsys = {
 	.can_attach	= cpu_cgroup_can_attach,
 	.attach		= cpu_cgroup_attach,
 	.exit		= cpu_cgroup_exit,
-	.subsys_id	= cpu_cgroup_subsys_id,
 	.base_cftypes	= cpu_files,
 	.early_init	= 1,
 };
diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c
index 622e0818f905..c143ee380e3a 100644
--- a/kernel/sched/cpuacct.c
+++ b/kernel/sched/cpuacct.c
@@ -41,7 +41,7 @@ static inline struct cpuacct *css_ca(struct cgroup_subsys_state *css)
 /* return cpu accounting group to which this task belongs */
 static inline struct cpuacct *task_ca(struct task_struct *tsk)
 {
-	return css_ca(task_css(tsk, cpuacct_subsys_id));
+	return css_ca(task_css(tsk, cpuacct_cgrp_id));
 }
 
 static inline struct cpuacct *parent_ca(struct cpuacct *ca)
@@ -275,11 +275,9 @@ void cpuacct_account_field(struct task_struct *p, int index, u64 val)
 	rcu_read_unlock();
 }
 
-struct cgroup_subsys cpuacct_subsys = {
-	.name		= "cpuacct",
+struct cgroup_subsys cpuacct_cgrp_subsys = {
 	.css_alloc	= cpuacct_css_alloc,
 	.css_free	= cpuacct_css_free,
-	.subsys_id	= cpuacct_subsys_id,
 	.base_cftypes	= files,
 	.early_init	= 1,
 };
diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c
index 5b9bb42b2d47..bd95963dae80 100644
--- a/kernel/sched/cpudeadline.c
+++ b/kernel/sched/cpudeadline.c
@@ -13,6 +13,7 @@
 
 #include <linux/gfp.h>
 #include <linux/kernel.h>
+#include <linux/slab.h>
 #include "cpudeadline.h"
 
 static inline int parent(int i)
@@ -39,8 +40,10 @@ static void cpudl_exchange(struct cpudl *cp, int a, int b)
 {
 	int cpu_a = cp->elements[a].cpu, cpu_b = cp->elements[b].cpu;
 
-	swap(cp->elements[a], cp->elements[b]);
-	swap(cp->cpu_to_idx[cpu_a], cp->cpu_to_idx[cpu_b]);
+	swap(cp->elements[a].cpu, cp->elements[b].cpu);
+	swap(cp->elements[a].dl , cp->elements[b].dl );
+
+	swap(cp->elements[cpu_a].idx, cp->elements[cpu_b].idx);
 }
 
 static void cpudl_heapify(struct cpudl *cp, int idx)
@@ -140,7 +143,7 @@ void cpudl_set(struct cpudl *cp, int cpu, u64 dl, int is_valid)
 	WARN_ON(!cpu_present(cpu));
 
 	raw_spin_lock_irqsave(&cp->lock, flags);
-	old_idx = cp->cpu_to_idx[cpu];
+	old_idx = cp->elements[cpu].idx;
 	if (!is_valid) {
 		/* remove item */
 		if (old_idx == IDX_INVALID) {
@@ -155,8 +158,8 @@ void cpudl_set(struct cpudl *cp, int cpu, u64 dl, int is_valid)
 		cp->elements[old_idx].dl = cp->elements[cp->size - 1].dl;
 		cp->elements[old_idx].cpu = new_cpu;
 		cp->size--;
-		cp->cpu_to_idx[new_cpu] = old_idx;
-		cp->cpu_to_idx[cpu] = IDX_INVALID;
+		cp->elements[new_cpu].idx = old_idx;
+		cp->elements[cpu].idx = IDX_INVALID;
 		while (old_idx > 0 && dl_time_before(
 				cp->elements[parent(old_idx)].dl,
 				cp->elements[old_idx].dl)) {
@@ -173,7 +176,7 @@ void cpudl_set(struct cpudl *cp, int cpu, u64 dl, int is_valid)
 		cp->size++;
 		cp->elements[cp->size - 1].dl = 0;
 		cp->elements[cp->size - 1].cpu = cpu;
-		cp->cpu_to_idx[cpu] = cp->size - 1;
+		cp->elements[cpu].idx = cp->size - 1;
 		cpudl_change_key(cp, cp->size - 1, dl);
 		cpumask_clear_cpu(cpu, cp->free_cpus);
 	} else {
@@ -195,10 +198,21 @@ int cpudl_init(struct cpudl *cp)
 	memset(cp, 0, sizeof(*cp));
 	raw_spin_lock_init(&cp->lock);
 	cp->size = 0;
-	for (i = 0; i < NR_CPUS; i++)
-		cp->cpu_to_idx[i] = IDX_INVALID;
-	if (!alloc_cpumask_var(&cp->free_cpus, GFP_KERNEL))
+
+	cp->elements = kcalloc(nr_cpu_ids,
+			       sizeof(struct cpudl_item),
+			       GFP_KERNEL);
+	if (!cp->elements)
+		return -ENOMEM;
+
+	if (!alloc_cpumask_var(&cp->free_cpus, GFP_KERNEL)) {
+		kfree(cp->elements);
 		return -ENOMEM;
+	}
+
+	for_each_possible_cpu(i)
+		cp->elements[i].idx = IDX_INVALID;
+
 	cpumask_setall(cp->free_cpus);
 
 	return 0;
@@ -210,7 +224,6 @@ int cpudl_init(struct cpudl *cp)
  */
 void cpudl_cleanup(struct cpudl *cp)
 {
-	/*
-	 * nothing to do for the moment
-	 */
+	free_cpumask_var(cp->free_cpus);
+	kfree(cp->elements);
 }
diff --git a/kernel/sched/cpudeadline.h b/kernel/sched/cpudeadline.h
index a202789a412c..538c9796ad4a 100644
--- a/kernel/sched/cpudeadline.h
+++ b/kernel/sched/cpudeadline.h
@@ -5,17 +5,17 @@
 
 #define IDX_INVALID     -1
 
-struct array_item {
+struct cpudl_item {
 	u64 dl;
 	int cpu;
+	int idx;
 };
 
 struct cpudl {
 	raw_spinlock_t lock;
 	int size;
-	int cpu_to_idx[NR_CPUS];
-	struct array_item elements[NR_CPUS];
 	cpumask_var_t free_cpus;
+	struct cpudl_item *elements;
 };
 
 
diff --git a/kernel/sched/cpupri.c b/kernel/sched/cpupri.c
index 8b836b376d91..8834243abee2 100644
--- a/kernel/sched/cpupri.c
+++ b/kernel/sched/cpupri.c
@@ -30,6 +30,7 @@
 #include <linux/gfp.h>
 #include <linux/sched.h>
 #include <linux/sched/rt.h>
+#include <linux/slab.h>
 #include "cpupri.h"
 
 /* Convert between a 140 based task->prio, and our 102 based cpupri */
@@ -70,8 +71,7 @@ int cpupri_find(struct cpupri *cp, struct task_struct *p,
 	int idx = 0;
 	int task_pri = convert_prio(p->prio);
 
-	if (task_pri >= MAX_RT_PRIO)
-		return 0;
+	BUG_ON(task_pri >= CPUPRI_NR_PRIORITIES);
 
 	for (idx = 0; idx < task_pri; idx++) {
 		struct cpupri_vec *vec  = &cp->pri_to_cpu[idx];
@@ -219,8 +219,13 @@ int cpupri_init(struct cpupri *cp)
 			goto cleanup;
 	}
 
+	cp->cpu_to_pri = kcalloc(nr_cpu_ids, sizeof(int), GFP_KERNEL);
+	if (!cp->cpu_to_pri)
+		goto cleanup;
+
 	for_each_possible_cpu(i)
 		cp->cpu_to_pri[i] = CPUPRI_INVALID;
+
 	return 0;
 
 cleanup:
@@ -237,6 +242,7 @@ void cpupri_cleanup(struct cpupri *cp)
 {
 	int i;
 
+	kfree(cp->cpu_to_pri);
 	for (i = 0; i < CPUPRI_NR_PRIORITIES; i++)
 		free_cpumask_var(cp->pri_to_cpu[i].mask);
 }
diff --git a/kernel/sched/cpupri.h b/kernel/sched/cpupri.h
index f6d756173491..6b033347fdfd 100644
--- a/kernel/sched/cpupri.h
+++ b/kernel/sched/cpupri.h
@@ -17,7 +17,7 @@ struct cpupri_vec {
 
 struct cpupri {
 	struct cpupri_vec pri_to_cpu[CPUPRI_NR_PRIORITIES];
-	int               cpu_to_pri[NR_CPUS];
+	int *cpu_to_pri;
 };
 
 #ifdef CONFIG_SMP
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index 99947919e30b..72fdf06ef865 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -142,7 +142,7 @@ void account_user_time(struct task_struct *p, cputime_t cputime,
 	p->utimescaled += cputime_scaled;
 	account_group_user_time(p, cputime);
 
-	index = (TASK_NICE(p) > 0) ? CPUTIME_NICE : CPUTIME_USER;
+	index = (task_nice(p) > 0) ? CPUTIME_NICE : CPUTIME_USER;
 
 	/* Add user time to cpustat. */
 	task_group_account_field(p, index, (__force u64) cputime);
@@ -169,7 +169,7 @@ static void account_guest_time(struct task_struct *p, cputime_t cputime,
 	p->gtime += cputime;
 
 	/* Add guest time to cpustat. */
-	if (TASK_NICE(p) > 0) {
+	if (task_nice(p) > 0) {
 		cpustat[CPUTIME_NICE] += (__force u64) cputime;
 		cpustat[CPUTIME_GUEST_NICE] += (__force u64) cputime;
 	} else {
@@ -258,16 +258,22 @@ static __always_inline bool steal_account_process_tick(void)
 {
 #ifdef CONFIG_PARAVIRT
 	if (static_key_false(&paravirt_steal_enabled)) {
-		u64 steal, st = 0;
+		u64 steal;
+		cputime_t steal_ct;
 
 		steal = paravirt_steal_clock(smp_processor_id());
 		steal -= this_rq()->prev_steal_time;
 
-		st = steal_ticks(steal);
-		this_rq()->prev_steal_time += st * TICK_NSEC;
+		/*
+		 * cputime_t may be less precise than nsecs (eg: if it's
+		 * based on jiffies). Lets cast the result to cputime
+		 * granularity and account the rest on the next rounds.
+		 */
+		steal_ct = nsecs_to_cputime(steal);
+		this_rq()->prev_steal_time += cputime_to_nsecs(steal_ct);
 
-		account_steal_time(st);
-		return st;
+		account_steal_time(steal_ct);
+		return steal_ct;
 	}
 #endif
 	return false;
@@ -326,50 +332,50 @@ out:
  * softirq as those do not count in task exec_runtime any more.
  */
 static void irqtime_account_process_tick(struct task_struct *p, int user_tick,
-						struct rq *rq)
+					 struct rq *rq, int ticks)
 {
-	cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy);
+	cputime_t scaled = cputime_to_scaled(cputime_one_jiffy);
+	u64 cputime = (__force u64) cputime_one_jiffy;
 	u64 *cpustat = kcpustat_this_cpu->cpustat;
 
 	if (steal_account_process_tick())
 		return;
 
+	cputime *= ticks;
+	scaled *= ticks;
+
 	if (irqtime_account_hi_update()) {
-		cpustat[CPUTIME_IRQ] += (__force u64) cputime_one_jiffy;
+		cpustat[CPUTIME_IRQ] += cputime;
 	} else if (irqtime_account_si_update()) {
-		cpustat[CPUTIME_SOFTIRQ] += (__force u64) cputime_one_jiffy;
+		cpustat[CPUTIME_SOFTIRQ] += cputime;
 	} else if (this_cpu_ksoftirqd() == p) {
 		/*
 		 * ksoftirqd time do not get accounted in cpu_softirq_time.
 		 * So, we have to handle it separately here.
 		 * Also, p->stime needs to be updated for ksoftirqd.
 		 */
-		__account_system_time(p, cputime_one_jiffy, one_jiffy_scaled,
-					CPUTIME_SOFTIRQ);
+		__account_system_time(p, cputime, scaled, CPUTIME_SOFTIRQ);
 	} else if (user_tick) {
-		account_user_time(p, cputime_one_jiffy, one_jiffy_scaled);
+		account_user_time(p, cputime, scaled);
 	} else if (p == rq->idle) {
-		account_idle_time(cputime_one_jiffy);
+		account_idle_time(cputime);
 	} else if (p->flags & PF_VCPU) { /* System time or guest time */
-		account_guest_time(p, cputime_one_jiffy, one_jiffy_scaled);
+		account_guest_time(p, cputime, scaled);
 	} else {
-		__account_system_time(p, cputime_one_jiffy, one_jiffy_scaled,
-					CPUTIME_SYSTEM);
+		__account_system_time(p, cputime, scaled,	CPUTIME_SYSTEM);
 	}
 }
 
 static void irqtime_account_idle_ticks(int ticks)
 {
-	int i;
 	struct rq *rq = this_rq();
 
-	for (i = 0; i < ticks; i++)
-		irqtime_account_process_tick(current, 0, rq);
+	irqtime_account_process_tick(current, 0, rq, ticks);
 }
 #else /* CONFIG_IRQ_TIME_ACCOUNTING */
 static inline void irqtime_account_idle_ticks(int ticks) {}
 static inline void irqtime_account_process_tick(struct task_struct *p, int user_tick,
-						struct rq *rq) {}
+						struct rq *rq, int nr_ticks) {}
 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
 
 /*
@@ -458,7 +464,7 @@ void account_process_tick(struct task_struct *p, int user_tick)
 		return;
 
 	if (sched_clock_irqtime) {
-		irqtime_account_process_tick(p, user_tick, rq);
+		irqtime_account_process_tick(p, user_tick, rq, 1);
 		return;
 	}
 
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 6e79b3faa4cd..14bc348ba3b4 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -210,6 +210,16 @@ static inline int has_pushable_dl_tasks(struct rq *rq)
 
 static int push_dl_task(struct rq *rq);
 
+static inline bool need_pull_dl_task(struct rq *rq, struct task_struct *prev)
+{
+	return dl_task(prev);
+}
+
+static inline void set_post_schedule(struct rq *rq)
+{
+	rq->post_schedule = has_pushable_dl_tasks(rq);
+}
+
 #else
 
 static inline
@@ -232,6 +242,19 @@ void dec_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
 {
 }
 
+static inline bool need_pull_dl_task(struct rq *rq, struct task_struct *prev)
+{
+	return false;
+}
+
+static inline int pull_dl_task(struct rq *rq)
+{
+	return 0;
+}
+
+static inline void set_post_schedule(struct rq *rq)
+{
+}
 #endif /* CONFIG_SMP */
 
 static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags);
@@ -490,9 +513,17 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
 						     struct sched_dl_entity,
 						     dl_timer);
 	struct task_struct *p = dl_task_of(dl_se);
-	struct rq *rq = task_rq(p);
+	struct rq *rq;
+again:
+	rq = task_rq(p);
 	raw_spin_lock(&rq->lock);
 
+	if (rq != task_rq(p)) {
+		/* Task was moved, retrying. */
+		raw_spin_unlock(&rq->lock);
+		goto again;
+	}
+
 	/*
 	 * We need to take care of a possible races here. In fact, the
 	 * task might have changed its scheduling policy to something
@@ -505,6 +536,7 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
 	sched_clock_tick();
 	update_rq_clock(rq);
 	dl_se->dl_throttled = 0;
+	dl_se->dl_yielded = 0;
 	if (p->on_rq) {
 		enqueue_task_dl(rq, p, ENQUEUE_REPLENISH);
 		if (task_has_dl_policy(rq->curr))
@@ -586,8 +618,8 @@ static void update_curr_dl(struct rq *rq)
 	 * approach need further study.
 	 */
 	delta_exec = rq_clock_task(rq) - curr->se.exec_start;
-	if (unlikely((s64)delta_exec < 0))
-		delta_exec = 0;
+	if (unlikely((s64)delta_exec <= 0))
+		return;
 
 	schedstat_set(curr->se.statistics.exec_max,
 		      max(curr->se.statistics.exec_max, delta_exec));
@@ -870,10 +902,10 @@ static void yield_task_dl(struct rq *rq)
 	 * We make the task go to sleep until its current deadline by
 	 * forcing its runtime to zero. This way, update_curr_dl() stops
 	 * it and the bandwidth timer will wake it up and will give it
-	 * new scheduling parameters (thanks to dl_new=1).
+	 * new scheduling parameters (thanks to dl_yielded=1).
 	 */
 	if (p->dl.runtime > 0) {
-		rq->curr->dl.dl_new = 1;
+		rq->curr->dl.dl_yielded = 1;
 		p->dl.runtime = 0;
 	}
 	update_curr_dl(rq);
@@ -942,6 +974,8 @@ static void check_preempt_equal_dl(struct rq *rq, struct task_struct *p)
 	resched_task(rq->curr);
 }
 
+static int pull_dl_task(struct rq *this_rq);
+
 #endif /* CONFIG_SMP */
 
 /*
@@ -988,7 +1022,7 @@ static struct sched_dl_entity *pick_next_dl_entity(struct rq *rq,
 	return rb_entry(left, struct sched_dl_entity, rb_node);
 }
 
-struct task_struct *pick_next_task_dl(struct rq *rq)
+struct task_struct *pick_next_task_dl(struct rq *rq, struct task_struct *prev)
 {
 	struct sched_dl_entity *dl_se;
 	struct task_struct *p;
@@ -996,9 +1030,29 @@ struct task_struct *pick_next_task_dl(struct rq *rq)
 
 	dl_rq = &rq->dl;
 
+	if (need_pull_dl_task(rq, prev)) {
+		pull_dl_task(rq);
+		/*
+		 * pull_rt_task() can drop (and re-acquire) rq->lock; this
+		 * means a stop task can slip in, in which case we need to
+		 * re-start task selection.
+		 */
+		if (rq->stop && rq->stop->on_rq)
+			return RETRY_TASK;
+	}
+
+	/*
+	 * When prev is DL, we may throttle it in put_prev_task().
+	 * So, we update time before we check for dl_nr_running.
+	 */
+	if (prev->sched_class == &dl_sched_class)
+		update_curr_dl(rq);
+
 	if (unlikely(!dl_rq->dl_nr_running))
 		return NULL;
 
+	put_prev_task(rq, prev);
+
 	dl_se = pick_next_dl_entity(rq, dl_rq);
 	BUG_ON(!dl_se);
 
@@ -1013,9 +1067,7 @@ struct task_struct *pick_next_task_dl(struct rq *rq)
 		start_hrtick_dl(rq, p);
 #endif
 
-#ifdef CONFIG_SMP
-	rq->post_schedule = has_pushable_dl_tasks(rq);
-#endif /* CONFIG_SMP */
+	set_post_schedule(rq);
 
 	return p;
 }
@@ -1424,13 +1476,6 @@ skip:
 	return ret;
 }
 
-static void pre_schedule_dl(struct rq *rq, struct task_struct *prev)
-{
-	/* Try to pull other tasks here */
-	if (dl_task(prev))
-		pull_dl_task(rq);
-}
-
 static void post_schedule_dl(struct rq *rq)
 {
 	push_dl_tasks(rq);
@@ -1558,7 +1603,7 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p)
 	if (unlikely(p->dl.dl_throttled))
 		return;
 
-	if (p->on_rq || rq->curr != p) {
+	if (p->on_rq && rq->curr != p) {
 #ifdef CONFIG_SMP
 		if (rq->dl.overloaded && push_dl_task(rq) && rq != task_rq(p))
 			/* Only reschedule if pushing failed */
@@ -1623,7 +1668,6 @@ const struct sched_class dl_sched_class = {
 	.set_cpus_allowed       = set_cpus_allowed_dl,
 	.rq_online              = rq_online_dl,
 	.rq_offline             = rq_offline_dl,
-	.pre_schedule		= pre_schedule_dl,
 	.post_schedule		= post_schedule_dl,
 	.task_woken		= task_woken_dl,
 #endif
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index dd52e7ffb10e..695f9773bb60 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -111,8 +111,7 @@ static char *task_group_path(struct task_group *tg)
 	if (autogroup_path(tg, group_path, PATH_MAX))
 		return group_path;
 
-	cgroup_path(tg->css.cgroup, group_path, PATH_MAX);
-	return group_path;
+	return cgroup_path(tg->css.cgroup, group_path, PATH_MAX);
 }
 #endif
 
@@ -321,6 +320,7 @@ do {									\
 	P(sched_goidle);
 #ifdef CONFIG_SMP
 	P64(avg_idle);
+	P64(max_idle_balance_cost);
 #endif
 
 	P(ttwu_count);
@@ -533,15 +533,15 @@ static void sched_show_numa(struct task_struct *p, struct seq_file *m)
 			unsigned long nr_faults = -1;
 			int cpu_current, home_node;
 
-			if (p->numa_faults)
-				nr_faults = p->numa_faults[2*node + i];
+			if (p->numa_faults_memory)
+				nr_faults = p->numa_faults_memory[2*node + i];
 
 			cpu_current = !i ? (task_node(p) == node) :
 				(pol && node_isset(node, pol->v.nodes));
 
 			home_node = (p->numa_preferred_nid == node);
 
-			SEQ_printf(m, "numa_faults, %d, %d, %d, %d, %ld\n",
+			SEQ_printf(m, "numa_faults_memory, %d, %d, %d, %d, %ld\n",
 				i, node, cpu_current, home_node, nr_faults);
 		}
 	}
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 9b4c4f320130..8cbe2d2c16de 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -322,13 +322,13 @@ static inline void list_del_leaf_cfs_rq(struct cfs_rq *cfs_rq)
 	list_for_each_entry_rcu(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list)
 
 /* Do the two (enqueued) entities belong to the same group ? */
-static inline int
+static inline struct cfs_rq *
 is_same_group(struct sched_entity *se, struct sched_entity *pse)
 {
 	if (se->cfs_rq == pse->cfs_rq)
-		return 1;
+		return se->cfs_rq;
 
-	return 0;
+	return NULL;
 }
 
 static inline struct sched_entity *parent_entity(struct sched_entity *se)
@@ -336,17 +336,6 @@ static inline struct sched_entity *parent_entity(struct sched_entity *se)
 	return se->parent;
 }
 
-/* return depth at which a sched entity is present in the hierarchy */
-static inline int depth_se(struct sched_entity *se)
-{
-	int depth = 0;
-
-	for_each_sched_entity(se)
-		depth++;
-
-	return depth;
-}
-
 static void
 find_matching_se(struct sched_entity **se, struct sched_entity **pse)
 {
@@ -360,8 +349,8 @@ find_matching_se(struct sched_entity **se, struct sched_entity **pse)
 	 */
 
 	/* First walk up until both entities are at same depth */
-	se_depth = depth_se(*se);
-	pse_depth = depth_se(*pse);
+	se_depth = (*se)->depth;
+	pse_depth = (*pse)->depth;
 
 	while (se_depth > pse_depth) {
 		se_depth--;
@@ -426,12 +415,6 @@ static inline void list_del_leaf_cfs_rq(struct cfs_rq *cfs_rq)
 #define for_each_leaf_cfs_rq(rq, cfs_rq) \
 		for (cfs_rq = &rq->cfs; cfs_rq; cfs_rq = NULL)
 
-static inline int
-is_same_group(struct sched_entity *se, struct sched_entity *pse)
-{
-	return 1;
-}
-
 static inline struct sched_entity *parent_entity(struct sched_entity *se)
 {
 	return NULL;
@@ -819,14 +802,6 @@ unsigned int sysctl_numa_balancing_scan_size = 256;
 /* Scan @scan_size MB every @scan_period after an initial @scan_delay in ms */
 unsigned int sysctl_numa_balancing_scan_delay = 1000;
 
-/*
- * After skipping a page migration on a shared page, skip N more numa page
- * migrations unconditionally. This reduces the number of NUMA migrations
- * in shared memory workloads, and has the effect of pulling tasks towards
- * where their memory lives, over pulling the memory towards the task.
- */
-unsigned int sysctl_numa_balancing_migrate_deferred = 16;
-
 static unsigned int task_nr_scan_windows(struct task_struct *p)
 {
 	unsigned long rss = 0;
@@ -893,10 +868,26 @@ struct numa_group {
 	struct list_head task_list;
 
 	struct rcu_head rcu;
+	nodemask_t active_nodes;
 	unsigned long total_faults;
+	/*
+	 * Faults_cpu is used to decide whether memory should move
+	 * towards the CPU. As a consequence, these stats are weighted
+	 * more by CPU use than by memory faults.
+	 */
+	unsigned long *faults_cpu;
 	unsigned long faults[0];
 };
 
+/* Shared or private faults. */
+#define NR_NUMA_HINT_FAULT_TYPES 2
+
+/* Memory and CPU locality */
+#define NR_NUMA_HINT_FAULT_STATS (NR_NUMA_HINT_FAULT_TYPES * 2)
+
+/* Averaged statistics, and temporary buffers. */
+#define NR_NUMA_HINT_FAULT_BUCKETS (NR_NUMA_HINT_FAULT_STATS * 2)
+
 pid_t task_numa_group_id(struct task_struct *p)
 {
 	return p->numa_group ? p->numa_group->gid : 0;
@@ -904,16 +895,16 @@ pid_t task_numa_group_id(struct task_struct *p)
 
 static inline int task_faults_idx(int nid, int priv)
 {
-	return 2 * nid + priv;
+	return NR_NUMA_HINT_FAULT_TYPES * nid + priv;
 }
 
 static inline unsigned long task_faults(struct task_struct *p, int nid)
 {
-	if (!p->numa_faults)
+	if (!p->numa_faults_memory)
 		return 0;
 
-	return p->numa_faults[task_faults_idx(nid, 0)] +
-		p->numa_faults[task_faults_idx(nid, 1)];
+	return p->numa_faults_memory[task_faults_idx(nid, 0)] +
+		p->numa_faults_memory[task_faults_idx(nid, 1)];
 }
 
 static inline unsigned long group_faults(struct task_struct *p, int nid)
@@ -925,6 +916,12 @@ static inline unsigned long group_faults(struct task_struct *p, int nid)
 		p->numa_group->faults[task_faults_idx(nid, 1)];
 }
 
+static inline unsigned long group_faults_cpu(struct numa_group *group, int nid)
+{
+	return group->faults_cpu[task_faults_idx(nid, 0)] +
+		group->faults_cpu[task_faults_idx(nid, 1)];
+}
+
 /*
  * These return the fraction of accesses done by a particular task, or
  * task group, on a particular numa node.  The group weight is given a
@@ -935,7 +932,7 @@ static inline unsigned long task_weight(struct task_struct *p, int nid)
 {
 	unsigned long total_faults;
 
-	if (!p->numa_faults)
+	if (!p->numa_faults_memory)
 		return 0;
 
 	total_faults = p->total_numa_faults;
@@ -954,6 +951,69 @@ static inline unsigned long group_weight(struct task_struct *p, int nid)
 	return 1000 * group_faults(p, nid) / p->numa_group->total_faults;
 }
 
+bool should_numa_migrate_memory(struct task_struct *p, struct page * page,
+				int src_nid, int dst_cpu)
+{
+	struct numa_group *ng = p->numa_group;
+	int dst_nid = cpu_to_node(dst_cpu);
+	int last_cpupid, this_cpupid;
+
+	this_cpupid = cpu_pid_to_cpupid(dst_cpu, current->pid);
+
+	/*
+	 * Multi-stage node selection is used in conjunction with a periodic
+	 * migration fault to build a temporal task<->page relation. By using
+	 * a two-stage filter we remove short/unlikely relations.
+	 *
+	 * Using P(p) ~ n_p / n_t as per frequentist probability, we can equate
+	 * a task's usage of a particular page (n_p) per total usage of this
+	 * page (n_t) (in a given time-span) to a probability.
+	 *
+	 * Our periodic faults will sample this probability and getting the
+	 * same result twice in a row, given these samples are fully
+	 * independent, is then given by P(n)^2, provided our sample period
+	 * is sufficiently short compared to the usage pattern.
+	 *
+	 * This quadric squishes small probabilities, making it less likely we
+	 * act on an unlikely task<->page relation.
+	 */
+	last_cpupid = page_cpupid_xchg_last(page, this_cpupid);
+	if (!cpupid_pid_unset(last_cpupid) &&
+				cpupid_to_nid(last_cpupid) != dst_nid)
+		return false;
+
+	/* Always allow migrate on private faults */
+	if (cpupid_match_pid(p, last_cpupid))
+		return true;
+
+	/* A shared fault, but p->numa_group has not been set up yet. */
+	if (!ng)
+		return true;
+
+	/*
+	 * Do not migrate if the destination is not a node that
+	 * is actively used by this numa group.
+	 */
+	if (!node_isset(dst_nid, ng->active_nodes))
+		return false;
+
+	/*
+	 * Source is a node that is not actively used by this
+	 * numa group, while the destination is. Migrate.
+	 */
+	if (!node_isset(src_nid, ng->active_nodes))
+		return true;
+
+	/*
+	 * Both source and destination are nodes in active
+	 * use by this numa group. Maximize memory bandwidth
+	 * by migrating from more heavily used groups, to less
+	 * heavily used ones, spreading the load around.
+	 * Use a 1/4 hysteresis to avoid spurious page movement.
+	 */
+	return group_faults(p, dst_nid) < (group_faults(p, src_nid) * 3 / 4);
+}
+
 static unsigned long weighted_cpuload(const int cpu);
 static unsigned long source_load(int cpu, int type);
 static unsigned long target_load(int cpu, int type);
@@ -1267,7 +1327,7 @@ static int task_numa_migrate(struct task_struct *p)
 static void numa_migrate_preferred(struct task_struct *p)
 {
 	/* This task has no NUMA fault statistics yet */
-	if (unlikely(p->numa_preferred_nid == -1 || !p->numa_faults))
+	if (unlikely(p->numa_preferred_nid == -1 || !p->numa_faults_memory))
 		return;
 
 	/* Periodically retry migrating the task to the preferred node */
@@ -1282,6 +1342,38 @@ static void numa_migrate_preferred(struct task_struct *p)
 }
 
 /*
+ * Find the nodes on which the workload is actively running. We do this by
+ * tracking the nodes from which NUMA hinting faults are triggered. This can
+ * be different from the set of nodes where the workload's memory is currently
+ * located.
+ *
+ * The bitmask is used to make smarter decisions on when to do NUMA page
+ * migrations, To prevent flip-flopping, and excessive page migrations, nodes
+ * are added when they cause over 6/16 of the maximum number of faults, but
+ * only removed when they drop below 3/16.
+ */
+static void update_numa_active_node_mask(struct numa_group *numa_group)
+{
+	unsigned long faults, max_faults = 0;
+	int nid;
+
+	for_each_online_node(nid) {
+		faults = group_faults_cpu(numa_group, nid);
+		if (faults > max_faults)
+			max_faults = faults;
+	}
+
+	for_each_online_node(nid) {
+		faults = group_faults_cpu(numa_group, nid);
+		if (!node_isset(nid, numa_group->active_nodes)) {
+			if (faults > max_faults * 6 / 16)
+				node_set(nid, numa_group->active_nodes);
+		} else if (faults < max_faults * 3 / 16)
+			node_clear(nid, numa_group->active_nodes);
+	}
+}
+
+/*
  * When adapting the scan rate, the period is divided into NUMA_PERIOD_SLOTS
  * increments. The more local the fault statistics are, the higher the scan
  * period will be for the next scan window. If local/remote ratio is below
@@ -1355,11 +1447,41 @@ static void update_task_scan_period(struct task_struct *p,
 	memset(p->numa_faults_locality, 0, sizeof(p->numa_faults_locality));
 }
 
+/*
+ * Get the fraction of time the task has been running since the last
+ * NUMA placement cycle. The scheduler keeps similar statistics, but
+ * decays those on a 32ms period, which is orders of magnitude off
+ * from the dozens-of-seconds NUMA balancing period. Use the scheduler
+ * stats only if the task is so new there are no NUMA statistics yet.
+ */
+static u64 numa_get_avg_runtime(struct task_struct *p, u64 *period)
+{
+	u64 runtime, delta, now;
+	/* Use the start of this time slice to avoid calculations. */
+	now = p->se.exec_start;
+	runtime = p->se.sum_exec_runtime;
+
+	if (p->last_task_numa_placement) {
+		delta = runtime - p->last_sum_exec_runtime;
+		*period = now - p->last_task_numa_placement;
+	} else {
+		delta = p->se.avg.runnable_avg_sum;
+		*period = p->se.avg.runnable_avg_period;
+	}
+
+	p->last_sum_exec_runtime = runtime;
+	p->last_task_numa_placement = now;
+
+	return delta;
+}
+
 static void task_numa_placement(struct task_struct *p)
 {
 	int seq, nid, max_nid = -1, max_group_nid = -1;
 	unsigned long max_faults = 0, max_group_faults = 0;
 	unsigned long fault_types[2] = { 0, 0 };
+	unsigned long total_faults;
+	u64 runtime, period;
 	spinlock_t *group_lock = NULL;
 
 	seq = ACCESS_ONCE(p->mm->numa_scan_seq);
@@ -1368,10 +1490,14 @@ static void task_numa_placement(struct task_struct *p)
 	p->numa_scan_seq = seq;
 	p->numa_scan_period_max = task_scan_max(p);
 
+	total_faults = p->numa_faults_locality[0] +
+		       p->numa_faults_locality[1];
+	runtime = numa_get_avg_runtime(p, &period);
+
 	/* If the task is part of a group prevent parallel updates to group stats */
 	if (p->numa_group) {
 		group_lock = &p->numa_group->lock;
-		spin_lock(group_lock);
+		spin_lock_irq(group_lock);
 	}
 
 	/* Find the node with the highest number of faults */
@@ -1379,24 +1505,37 @@ static void task_numa_placement(struct task_struct *p)
 		unsigned long faults = 0, group_faults = 0;
 		int priv, i;
 
-		for (priv = 0; priv < 2; priv++) {
-			long diff;
+		for (priv = 0; priv < NR_NUMA_HINT_FAULT_TYPES; priv++) {
+			long diff, f_diff, f_weight;
 
 			i = task_faults_idx(nid, priv);
-			diff = -p->numa_faults[i];
 
 			/* Decay existing window, copy faults since last scan */
-			p->numa_faults[i] >>= 1;
-			p->numa_faults[i] += p->numa_faults_buffer[i];
-			fault_types[priv] += p->numa_faults_buffer[i];
-			p->numa_faults_buffer[i] = 0;
+			diff = p->numa_faults_buffer_memory[i] - p->numa_faults_memory[i] / 2;
+			fault_types[priv] += p->numa_faults_buffer_memory[i];
+			p->numa_faults_buffer_memory[i] = 0;
 
-			faults += p->numa_faults[i];
-			diff += p->numa_faults[i];
+			/*
+			 * Normalize the faults_from, so all tasks in a group
+			 * count according to CPU use, instead of by the raw
+			 * number of faults. Tasks with little runtime have
+			 * little over-all impact on throughput, and thus their
+			 * faults are less important.
+			 */
+			f_weight = div64_u64(runtime << 16, period + 1);
+			f_weight = (f_weight * p->numa_faults_buffer_cpu[i]) /
+				   (total_faults + 1);
+			f_diff = f_weight - p->numa_faults_cpu[i] / 2;
+			p->numa_faults_buffer_cpu[i] = 0;
+
+			p->numa_faults_memory[i] += diff;
+			p->numa_faults_cpu[i] += f_diff;
+			faults += p->numa_faults_memory[i];
 			p->total_numa_faults += diff;
 			if (p->numa_group) {
 				/* safe because we can only change our own group */
 				p->numa_group->faults[i] += diff;
+				p->numa_group->faults_cpu[i] += f_diff;
 				p->numa_group->total_faults += diff;
 				group_faults += p->numa_group->faults[i];
 			}
@@ -1416,6 +1555,7 @@ static void task_numa_placement(struct task_struct *p)
 	update_task_scan_period(p, fault_types[0], fault_types[1]);
 
 	if (p->numa_group) {
+		update_numa_active_node_mask(p->numa_group);
 		/*
 		 * If the preferred task and group nids are different,
 		 * iterate over the nodes again to find the best place.
@@ -1432,7 +1572,7 @@ static void task_numa_placement(struct task_struct *p)
 			}
 		}
 
-		spin_unlock(group_lock);
+		spin_unlock_irq(group_lock);
 	}
 
 	/* Preferred node as the node with the most faults */
@@ -1465,7 +1605,7 @@ static void task_numa_group(struct task_struct *p, int cpupid, int flags,
 
 	if (unlikely(!p->numa_group)) {
 		unsigned int size = sizeof(struct numa_group) +
-				    2*nr_node_ids*sizeof(unsigned long);
+				    4*nr_node_ids*sizeof(unsigned long);
 
 		grp = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
 		if (!grp)
@@ -1475,9 +1615,14 @@ static void task_numa_group(struct task_struct *p, int cpupid, int flags,
 		spin_lock_init(&grp->lock);
 		INIT_LIST_HEAD(&grp->task_list);
 		grp->gid = p->pid;
+		/* Second half of the array tracks nids where faults happen */
+		grp->faults_cpu = grp->faults + NR_NUMA_HINT_FAULT_TYPES *
+						nr_node_ids;
 
-		for (i = 0; i < 2*nr_node_ids; i++)
-			grp->faults[i] = p->numa_faults[i];
+		node_set(task_node(current), grp->active_nodes);
+
+		for (i = 0; i < NR_NUMA_HINT_FAULT_STATS * nr_node_ids; i++)
+			grp->faults[i] = p->numa_faults_memory[i];
 
 		grp->total_faults = p->total_numa_faults;
 
@@ -1532,11 +1677,12 @@ static void task_numa_group(struct task_struct *p, int cpupid, int flags,
 	if (!join)
 		return;
 
-	double_lock(&my_grp->lock, &grp->lock);
+	BUG_ON(irqs_disabled());
+	double_lock_irq(&my_grp->lock, &grp->lock);
 
-	for (i = 0; i < 2*nr_node_ids; i++) {
-		my_grp->faults[i] -= p->numa_faults[i];
-		grp->faults[i] += p->numa_faults[i];
+	for (i = 0; i < NR_NUMA_HINT_FAULT_STATS * nr_node_ids; i++) {
+		my_grp->faults[i] -= p->numa_faults_memory[i];
+		grp->faults[i] += p->numa_faults_memory[i];
 	}
 	my_grp->total_faults -= p->total_numa_faults;
 	grp->total_faults += p->total_numa_faults;
@@ -1546,7 +1692,7 @@ static void task_numa_group(struct task_struct *p, int cpupid, int flags,
 	grp->nr_tasks++;
 
 	spin_unlock(&my_grp->lock);
-	spin_unlock(&grp->lock);
+	spin_unlock_irq(&grp->lock);
 
 	rcu_assign_pointer(p->numa_group, grp);
 
@@ -1561,34 +1707,38 @@ no_join:
 void task_numa_free(struct task_struct *p)
 {
 	struct numa_group *grp = p->numa_group;
+	void *numa_faults = p->numa_faults_memory;
+	unsigned long flags;
 	int i;
-	void *numa_faults = p->numa_faults;
 
 	if (grp) {
-		spin_lock(&grp->lock);
-		for (i = 0; i < 2*nr_node_ids; i++)
-			grp->faults[i] -= p->numa_faults[i];
+		spin_lock_irqsave(&grp->lock, flags);
+		for (i = 0; i < NR_NUMA_HINT_FAULT_STATS * nr_node_ids; i++)
+			grp->faults[i] -= p->numa_faults_memory[i];
 		grp->total_faults -= p->total_numa_faults;
 
 		list_del(&p->numa_entry);
 		grp->nr_tasks--;
-		spin_unlock(&grp->lock);
+		spin_unlock_irqrestore(&grp->lock, flags);
 		rcu_assign_pointer(p->numa_group, NULL);
 		put_numa_group(grp);
 	}
 
-	p->numa_faults = NULL;
-	p->numa_faults_buffer = NULL;
+	p->numa_faults_memory = NULL;
+	p->numa_faults_buffer_memory = NULL;
+	p->numa_faults_cpu= NULL;
+	p->numa_faults_buffer_cpu = NULL;
 	kfree(numa_faults);
 }
 
 /*
  * Got a PROT_NONE fault for a page on @node.
  */
-void task_numa_fault(int last_cpupid, int node, int pages, int flags)
+void task_numa_fault(int last_cpupid, int mem_node, int pages, int flags)
 {
 	struct task_struct *p = current;
 	bool migrated = flags & TNF_MIGRATED;
+	int cpu_node = task_node(current);
 	int priv;
 
 	if (!numabalancing_enabled)
@@ -1603,16 +1753,24 @@ void task_numa_fault(int last_cpupid, int node, int pages, int flags)
 		return;
 
 	/* Allocate buffer to track faults on a per-node basis */
-	if (unlikely(!p->numa_faults)) {
-		int size = sizeof(*p->numa_faults) * 2 * nr_node_ids;
+	if (unlikely(!p->numa_faults_memory)) {
+		int size = sizeof(*p->numa_faults_memory) *
+			   NR_NUMA_HINT_FAULT_BUCKETS * nr_node_ids;
 
-		/* numa_faults and numa_faults_buffer share the allocation */
-		p->numa_faults = kzalloc(size * 2, GFP_KERNEL|__GFP_NOWARN);
-		if (!p->numa_faults)
+		p->numa_faults_memory = kzalloc(size, GFP_KERNEL|__GFP_NOWARN);
+		if (!p->numa_faults_memory)
 			return;
 
-		BUG_ON(p->numa_faults_buffer);
-		p->numa_faults_buffer = p->numa_faults + (2 * nr_node_ids);
+		BUG_ON(p->numa_faults_buffer_memory);
+		/*
+		 * The averaged statistics, shared & private, memory & cpu,
+		 * occupy the first half of the array. The second half of the
+		 * array is for current counters, which are averaged into the
+		 * first set by task_numa_placement.
+		 */
+		p->numa_faults_cpu = p->numa_faults_memory + (2 * nr_node_ids);
+		p->numa_faults_buffer_memory = p->numa_faults_memory + (4 * nr_node_ids);
+		p->numa_faults_buffer_cpu = p->numa_faults_memory + (6 * nr_node_ids);
 		p->total_numa_faults = 0;
 		memset(p->numa_faults_locality, 0, sizeof(p->numa_faults_locality));
 	}
@@ -1641,7 +1799,8 @@ void task_numa_fault(int last_cpupid, int node, int pages, int flags)
 	if (migrated)
 		p->numa_pages_migrated += pages;
 
-	p->numa_faults_buffer[task_faults_idx(node, priv)] += pages;
+	p->numa_faults_buffer_memory[task_faults_idx(mem_node, priv)] += pages;
+	p->numa_faults_buffer_cpu[task_faults_idx(cpu_node, priv)] += pages;
 	p->numa_faults_locality[!!(flags & TNF_FAULT_LOCAL)] += pages;
 }
 
@@ -2219,13 +2378,20 @@ static inline void __update_group_entity_contrib(struct sched_entity *se)
 		se->avg.load_avg_contrib >>= NICE_0_SHIFT;
 	}
 }
-#else
+
+static inline void update_rq_runnable_avg(struct rq *rq, int runnable)
+{
+	__update_entity_runnable_avg(rq_clock_task(rq), &rq->avg, runnable);
+	__update_tg_runnable_avg(&rq->avg, &rq->cfs);
+}
+#else /* CONFIG_FAIR_GROUP_SCHED */
 static inline void __update_cfs_rq_tg_load_contrib(struct cfs_rq *cfs_rq,
 						 int force_update) {}
 static inline void __update_tg_runnable_avg(struct sched_avg *sa,
 						  struct cfs_rq *cfs_rq) {}
 static inline void __update_group_entity_contrib(struct sched_entity *se) {}
-#endif
+static inline void update_rq_runnable_avg(struct rq *rq, int runnable) {}
+#endif /* CONFIG_FAIR_GROUP_SCHED */
 
 static inline void __update_task_entity_contrib(struct sched_entity *se)
 {
@@ -2323,12 +2489,6 @@ static void update_cfs_rq_blocked_load(struct cfs_rq *cfs_rq, int force_update)
 	__update_cfs_rq_tg_load_contrib(cfs_rq, force_update);
 }
 
-static inline void update_rq_runnable_avg(struct rq *rq, int runnable)
-{
-	__update_entity_runnable_avg(rq_clock_task(rq), &rq->avg, runnable);
-	__update_tg_runnable_avg(&rq->avg, &rq->cfs);
-}
-
 /* Add the load generated by se into cfs_rq's child load-average */
 static inline void enqueue_entity_load_avg(struct cfs_rq *cfs_rq,
 						  struct sched_entity *se,
@@ -2416,7 +2576,10 @@ void idle_exit_fair(struct rq *this_rq)
 	update_rq_runnable_avg(this_rq, 0);
 }
 
-#else
+static int idle_balance(struct rq *this_rq);
+
+#else /* CONFIG_SMP */
+
 static inline void update_entity_load_avg(struct sched_entity *se,
 					  int update_cfs_rq) {}
 static inline void update_rq_runnable_avg(struct rq *rq, int runnable) {}
@@ -2428,7 +2591,13 @@ static inline void dequeue_entity_load_avg(struct cfs_rq *cfs_rq,
 					   int sleep) {}
 static inline void update_cfs_rq_blocked_load(struct cfs_rq *cfs_rq,
 					      int force_update) {}
-#endif
+
+static inline int idle_balance(struct rq *rq)
+{
+	return 0;
+}
+
+#endif /* CONFIG_SMP */
 
 static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
@@ -2578,10 +2747,10 @@ static void __clear_buddies_last(struct sched_entity *se)
 {
 	for_each_sched_entity(se) {
 		struct cfs_rq *cfs_rq = cfs_rq_of(se);
-		if (cfs_rq->last == se)
-			cfs_rq->last = NULL;
-		else
+		if (cfs_rq->last != se)
 			break;
+
+		cfs_rq->last = NULL;
 	}
 }
 
@@ -2589,10 +2758,10 @@ static void __clear_buddies_next(struct sched_entity *se)
 {
 	for_each_sched_entity(se) {
 		struct cfs_rq *cfs_rq = cfs_rq_of(se);
-		if (cfs_rq->next == se)
-			cfs_rq->next = NULL;
-		else
+		if (cfs_rq->next != se)
 			break;
+
+		cfs_rq->next = NULL;
 	}
 }
 
@@ -2600,10 +2769,10 @@ static void __clear_buddies_skip(struct sched_entity *se)
 {
 	for_each_sched_entity(se) {
 		struct cfs_rq *cfs_rq = cfs_rq_of(se);
-		if (cfs_rq->skip == se)
-			cfs_rq->skip = NULL;
-		else
+		if (cfs_rq->skip != se)
 			break;
+
+		cfs_rq->skip = NULL;
 	}
 }
 
@@ -2746,17 +2915,36 @@ wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se);
  * 3) pick the "last" process, for cache locality
  * 4) do not run the "skip" process, if something else is available
  */
-static struct sched_entity *pick_next_entity(struct cfs_rq *cfs_rq)
+static struct sched_entity *
+pick_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *curr)
 {
-	struct sched_entity *se = __pick_first_entity(cfs_rq);
-	struct sched_entity *left = se;
+	struct sched_entity *left = __pick_first_entity(cfs_rq);
+	struct sched_entity *se;
+
+	/*
+	 * If curr is set we have to see if its left of the leftmost entity
+	 * still in the tree, provided there was anything in the tree at all.
+	 */
+	if (!left || (curr && entity_before(curr, left)))
+		left = curr;
+
+	se = left; /* ideally we run the leftmost entity */
 
 	/*
 	 * Avoid running the skip buddy, if running something else can
 	 * be done without getting too unfair.
 	 */
 	if (cfs_rq->skip == se) {
-		struct sched_entity *second = __pick_next_entity(se);
+		struct sched_entity *second;
+
+		if (se == curr) {
+			second = __pick_first_entity(cfs_rq);
+		} else {
+			second = __pick_next_entity(se);
+			if (!second || (curr && entity_before(curr, second)))
+				second = curr;
+		}
+
 		if (second && wakeup_preempt_entity(second, left) < 1)
 			se = second;
 	}
@@ -2778,7 +2966,7 @@ static struct sched_entity *pick_next_entity(struct cfs_rq *cfs_rq)
 	return se;
 }
 
-static void check_cfs_rq_runtime(struct cfs_rq *cfs_rq);
+static bool check_cfs_rq_runtime(struct cfs_rq *cfs_rq);
 
 static void put_prev_entity(struct cfs_rq *cfs_rq, struct sched_entity *prev)
 {
@@ -2942,7 +3130,7 @@ static int assign_cfs_rq_runtime(struct cfs_rq *cfs_rq)
 		 */
 		if (!cfs_b->timer_active) {
 			__refill_cfs_bandwidth_runtime(cfs_b);
-			__start_cfs_bandwidth(cfs_b);
+			__start_cfs_bandwidth(cfs_b, false);
 		}
 
 		if (cfs_b->runtime > 0) {
@@ -3121,7 +3309,7 @@ static void throttle_cfs_rq(struct cfs_rq *cfs_rq)
 	raw_spin_lock(&cfs_b->lock);
 	list_add_tail_rcu(&cfs_rq->throttled_list, &cfs_b->throttled_cfs_rq);
 	if (!cfs_b->timer_active)
-		__start_cfs_bandwidth(cfs_b);
+		__start_cfs_bandwidth(cfs_b, false);
 	raw_spin_unlock(&cfs_b->lock);
 }
 
@@ -3433,22 +3621,23 @@ static void check_enqueue_throttle(struct cfs_rq *cfs_rq)
 }
 
 /* conditionally throttle active cfs_rq's from put_prev_entity() */
-static void check_cfs_rq_runtime(struct cfs_rq *cfs_rq)
+static bool check_cfs_rq_runtime(struct cfs_rq *cfs_rq)
 {
 	if (!cfs_bandwidth_used())
-		return;
+		return false;
 
 	if (likely(!cfs_rq->runtime_enabled || cfs_rq->runtime_remaining > 0))
-		return;
+		return false;
 
 	/*
 	 * it's possible for a throttled entity to be forced into a running
 	 * state (e.g. set_curr_task), in this case we're finished.
 	 */
 	if (cfs_rq_throttled(cfs_rq))
-		return;
+		return true;
 
 	throttle_cfs_rq(cfs_rq);
+	return true;
 }
 
 static enum hrtimer_restart sched_cfs_slack_timer(struct hrtimer *timer)
@@ -3502,7 +3691,7 @@ static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq)
 }
 
 /* requires cfs_b->lock, may release to reprogram timer */
-void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
+void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b, bool force)
 {
 	/*
 	 * The timer may be active because we're trying to set a new bandwidth
@@ -3517,7 +3706,7 @@ void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
 		cpu_relax();
 		raw_spin_lock(&cfs_b->lock);
 		/* if someone else restarted the timer then we're done */
-		if (cfs_b->timer_active)
+		if (!force && cfs_b->timer_active)
 			return;
 	}
 
@@ -3558,7 +3747,7 @@ static inline u64 cfs_rq_clock_task(struct cfs_rq *cfs_rq)
 }
 
 static void account_cfs_rq_runtime(struct cfs_rq *cfs_rq, u64 delta_exec) {}
-static void check_cfs_rq_runtime(struct cfs_rq *cfs_rq) {}
+static bool check_cfs_rq_runtime(struct cfs_rq *cfs_rq) { return false; }
 static void check_enqueue_throttle(struct cfs_rq *cfs_rq) {}
 static __always_inline void return_cfs_rq_runtime(struct cfs_rq *cfs_rq) {}
 
@@ -4213,13 +4402,14 @@ done:
 }
 
 /*
- * sched_balance_self: balance the current task (running on cpu) in domains
- * that have the 'flag' flag set. In practice, this is SD_BALANCE_FORK and
- * SD_BALANCE_EXEC.
+ * select_task_rq_fair: Select target runqueue for the waking task in domains
+ * that have the 'sd_flag' flag set. In practice, this is SD_BALANCE_WAKE,
+ * SD_BALANCE_FORK, or SD_BALANCE_EXEC.
  *
- * Balance, ie. select the least loaded group.
+ * Balances load by selecting the idlest cpu in the idlest group, or under
+ * certain conditions an idle sibling cpu if the domain has SD_WAKE_AFFINE set.
  *
- * Returns the target CPU number, or the same CPU if no balancing is needed.
+ * Returns the target cpu number.
  *
  * preempt must be disabled.
  */
@@ -4494,26 +4684,124 @@ preempt:
 		set_last_buddy(se);
 }
 
-static struct task_struct *pick_next_task_fair(struct rq *rq)
+static struct task_struct *
+pick_next_task_fair(struct rq *rq, struct task_struct *prev)
 {
-	struct task_struct *p;
 	struct cfs_rq *cfs_rq = &rq->cfs;
 	struct sched_entity *se;
+	struct task_struct *p;
+	int new_tasks;
 
+again:
+#ifdef CONFIG_FAIR_GROUP_SCHED
 	if (!cfs_rq->nr_running)
-		return NULL;
+		goto idle;
+
+	if (prev->sched_class != &fair_sched_class)
+		goto simple;
+
+	/*
+	 * Because of the set_next_buddy() in dequeue_task_fair() it is rather
+	 * likely that a next task is from the same cgroup as the current.
+	 *
+	 * Therefore attempt to avoid putting and setting the entire cgroup
+	 * hierarchy, only change the part that actually changes.
+	 */
 
 	do {
-		se = pick_next_entity(cfs_rq);
+		struct sched_entity *curr = cfs_rq->curr;
+
+		/*
+		 * Since we got here without doing put_prev_entity() we also
+		 * have to consider cfs_rq->curr. If it is still a runnable
+		 * entity, update_curr() will update its vruntime, otherwise
+		 * forget we've ever seen it.
+		 */
+		if (curr && curr->on_rq)
+			update_curr(cfs_rq);
+		else
+			curr = NULL;
+
+		/*
+		 * This call to check_cfs_rq_runtime() will do the throttle and
+		 * dequeue its entity in the parent(s). Therefore the 'simple'
+		 * nr_running test will indeed be correct.
+		 */
+		if (unlikely(check_cfs_rq_runtime(cfs_rq)))
+			goto simple;
+
+		se = pick_next_entity(cfs_rq, curr);
+		cfs_rq = group_cfs_rq(se);
+	} while (cfs_rq);
+
+	p = task_of(se);
+
+	/*
+	 * Since we haven't yet done put_prev_entity and if the selected task
+	 * is a different task than we started out with, try and touch the
+	 * least amount of cfs_rqs.
+	 */
+	if (prev != p) {
+		struct sched_entity *pse = &prev->se;
+
+		while (!(cfs_rq = is_same_group(se, pse))) {
+			int se_depth = se->depth;
+			int pse_depth = pse->depth;
+
+			if (se_depth <= pse_depth) {
+				put_prev_entity(cfs_rq_of(pse), pse);
+				pse = parent_entity(pse);
+			}
+			if (se_depth >= pse_depth) {
+				set_next_entity(cfs_rq_of(se), se);
+				se = parent_entity(se);
+			}
+		}
+
+		put_prev_entity(cfs_rq, pse);
+		set_next_entity(cfs_rq, se);
+	}
+
+	if (hrtick_enabled(rq))
+		hrtick_start_fair(rq, p);
+
+	return p;
+simple:
+	cfs_rq = &rq->cfs;
+#endif
+
+	if (!cfs_rq->nr_running)
+		goto idle;
+
+	put_prev_task(rq, prev);
+
+	do {
+		se = pick_next_entity(cfs_rq, NULL);
 		set_next_entity(cfs_rq, se);
 		cfs_rq = group_cfs_rq(se);
 	} while (cfs_rq);
 
 	p = task_of(se);
+
 	if (hrtick_enabled(rq))
 		hrtick_start_fair(rq, p);
 
 	return p;
+
+idle:
+	new_tasks = idle_balance(rq);
+	/*
+	 * Because idle_balance() releases (and re-acquires) rq->lock, it is
+	 * possible for any higher priority task to appear. In that case we
+	 * must re-start the pick_next_entity() loop.
+	 */
+	if (new_tasks < 0)
+		return RETRY_TASK;
+
+	if (new_tasks > 0)
+		goto again;
+
+	return NULL;
 }
 
 /*
@@ -4751,7 +5039,7 @@ static void move_task(struct task_struct *p, struct lb_env *env)
  * Is this task likely cache-hot:
  */
 static int
-task_hot(struct task_struct *p, u64 now, struct sched_domain *sd)
+task_hot(struct task_struct *p, u64 now)
 {
 	s64 delta;
 
@@ -4785,7 +5073,7 @@ static bool migrate_improves_locality(struct task_struct *p, struct lb_env *env)
 {
 	int src_nid, dst_nid;
 
-	if (!sched_feat(NUMA_FAVOUR_HIGHER) || !p->numa_faults ||
+	if (!sched_feat(NUMA_FAVOUR_HIGHER) || !p->numa_faults_memory ||
 	    !(env->sd->flags & SD_NUMA)) {
 		return false;
 	}
@@ -4816,7 +5104,7 @@ static bool migrate_degrades_locality(struct task_struct *p, struct lb_env *env)
 	if (!sched_feat(NUMA) || !sched_feat(NUMA_RESIST_LOWER))
 		return false;
 
-	if (!p->numa_faults || !(env->sd->flags & SD_NUMA))
+	if (!p->numa_faults_memory || !(env->sd->flags & SD_NUMA))
 		return false;
 
 	src_nid = cpu_to_node(env->src_cpu);
@@ -4912,7 +5200,7 @@ int can_migrate_task(struct task_struct *p, struct lb_env *env)
 	 * 2) task is cache cold, or
 	 * 3) too many balance attempts have failed.
 	 */
-	tsk_cache_hot = task_hot(p, rq_clock_task(env->src_rq), env->sd);
+	tsk_cache_hot = task_hot(p, rq_clock_task(env->src_rq));
 	if (!tsk_cache_hot)
 		tsk_cache_hot = migrate_degrades_locality(p, env);
 
@@ -5775,12 +6063,10 @@ void fix_small_imbalance(struct lb_env *env, struct sd_lb_stats *sds)
 	pwr_now /= SCHED_POWER_SCALE;
 
 	/* Amount of load we'd subtract */
-	tmp = (busiest->load_per_task * SCHED_POWER_SCALE) /
-		busiest->group_power;
-	if (busiest->avg_load > tmp) {
+	if (busiest->avg_load > scaled_busy_load_per_task) {
 		pwr_move += busiest->group_power *
 			    min(busiest->load_per_task,
-				busiest->avg_load - tmp);
+				busiest->avg_load - scaled_busy_load_per_task);
 	}
 
 	/* Amount of load we'd add */
@@ -6359,17 +6645,24 @@ out:
  * idle_balance is called by schedule() if this_cpu is about to become
  * idle. Attempts to pull tasks from other CPUs.
  */
-void idle_balance(int this_cpu, struct rq *this_rq)
+static int idle_balance(struct rq *this_rq)
 {
 	struct sched_domain *sd;
 	int pulled_task = 0;
 	unsigned long next_balance = jiffies + HZ;
 	u64 curr_cost = 0;
+	int this_cpu = this_rq->cpu;
+
+	idle_enter_fair(this_rq);
 
+	/*
+	 * We must set idle_stamp _before_ calling idle_balance(), such that we
+	 * measure the duration of idle_balance() as idle time.
+	 */
 	this_rq->idle_stamp = rq_clock(this_rq);
 
 	if (this_rq->avg_idle < sysctl_sched_migration_cost)
-		return;
+		goto out;
 
 	/*
 	 * Drop the rq->lock, but keep IRQ/preempt disabled.
@@ -6407,15 +6700,24 @@ void idle_balance(int this_cpu, struct rq *this_rq)
 		interval = msecs_to_jiffies(sd->balance_interval);
 		if (time_after(next_balance, sd->last_balance + interval))
 			next_balance = sd->last_balance + interval;
-		if (pulled_task) {
-			this_rq->idle_stamp = 0;
+		if (pulled_task)
 			break;
-		}
 	}
 	rcu_read_unlock();
 
 	raw_spin_lock(&this_rq->lock);
 
+	if (curr_cost > this_rq->max_idle_balance_cost)
+		this_rq->max_idle_balance_cost = curr_cost;
+
+	/*
+	 * While browsing the domains, we released the rq lock, a task could
+	 * have been enqueued in the meantime. Since we're not going idle,
+	 * pretend we pulled a task.
+	 */
+	if (this_rq->cfs.h_nr_running && !pulled_task)
+		pulled_task = 1;
+
 	if (pulled_task || time_after(jiffies, this_rq->next_balance)) {
 		/*
 		 * We are going idle. next_balance may be set based on
@@ -6424,8 +6726,20 @@ void idle_balance(int this_cpu, struct rq *this_rq)
 		this_rq->next_balance = next_balance;
 	}
 
-	if (curr_cost > this_rq->max_idle_balance_cost)
-		this_rq->max_idle_balance_cost = curr_cost;
+out:
+	/* Is there a task of a high priority class? */
+	if (this_rq->nr_running != this_rq->cfs.h_nr_running &&
+	    ((this_rq->stop && this_rq->stop->on_rq) ||
+	     this_rq->dl.dl_nr_running ||
+	     (this_rq->rt.rt_nr_running && !rt_rq_throttled(&this_rq->rt))))
+		pulled_task = -1;
+
+	if (pulled_task) {
+		idle_exit_fair(this_rq);
+		this_rq->idle_stamp = 0;
+	}
+
+	return pulled_task;
 }
 
 /*
@@ -6496,6 +6810,11 @@ out_unlock:
 	return 0;
 }
 
+static inline int on_null_domain(struct rq *rq)
+{
+	return unlikely(!rcu_dereference_sched(rq->sd));
+}
+
 #ifdef CONFIG_NO_HZ_COMMON
 /*
  * idle load balancing details
@@ -6550,8 +6869,13 @@ static void nohz_balancer_kick(void)
 static inline void nohz_balance_exit_idle(int cpu)
 {
 	if (unlikely(test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))) {
-		cpumask_clear_cpu(cpu, nohz.idle_cpus_mask);
-		atomic_dec(&nohz.nr_cpus);
+		/*
+		 * Completely isolated CPUs don't ever set, so we must test.
+		 */
+		if (likely(cpumask_test_cpu(cpu, nohz.idle_cpus_mask))) {
+			cpumask_clear_cpu(cpu, nohz.idle_cpus_mask);
+			atomic_dec(&nohz.nr_cpus);
+		}
 		clear_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu));
 	}
 }
@@ -6605,6 +6929,12 @@ void nohz_balance_enter_idle(int cpu)
 	if (test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))
 		return;
 
+	/*
+	 * If we're a completely isolated CPU, we don't play.
+	 */
+	if (on_null_domain(cpu_rq(cpu)))
+		return;
+
 	cpumask_set_cpu(cpu, nohz.idle_cpus_mask);
 	atomic_inc(&nohz.nr_cpus);
 	set_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu));
@@ -6867,11 +7197,6 @@ static void run_rebalance_domains(struct softirq_action *h)
 	nohz_idle_balance(this_rq, idle);
 }
 
-static inline int on_null_domain(struct rq *rq)
-{
-	return !rcu_dereference_sched(rq->sd);
-}
-
 /*
  * Trigger the SCHED_SOFTIRQ if it is time to do periodic load balancing.
  */
@@ -7036,7 +7361,15 @@ static void switched_from_fair(struct rq *rq, struct task_struct *p)
  */
 static void switched_to_fair(struct rq *rq, struct task_struct *p)
 {
-	if (!p->se.on_rq)
+	struct sched_entity *se = &p->se;
+#ifdef CONFIG_FAIR_GROUP_SCHED
+	/*
+	 * Since the real-depth could have been changed (only FAIR
+	 * class maintain depth value), reset depth properly.
+	 */
+	se->depth = se->parent ? se->parent->depth + 1 : 0;
+#endif
+	if (!se->on_rq)
 		return;
 
 	/*
@@ -7084,7 +7417,9 @@ void init_cfs_rq(struct cfs_rq *cfs_rq)
 #ifdef CONFIG_FAIR_GROUP_SCHED
 static void task_move_group_fair(struct task_struct *p, int on_rq)
 {
+	struct sched_entity *se = &p->se;
 	struct cfs_rq *cfs_rq;
+
 	/*
 	 * If the task was not on the rq at the time of this cgroup movement
 	 * it must have been asleep, sleeping tasks keep their ->vruntime
@@ -7110,23 +7445,24 @@ static void task_move_group_fair(struct task_struct *p, int on_rq)
 	 * To prevent boost or penalty in the new cfs_rq caused by delta
 	 * min_vruntime between the two cfs_rqs, we skip vruntime adjustment.
 	 */
-	if (!on_rq && (!p->se.sum_exec_runtime || p->state == TASK_WAKING))
+	if (!on_rq && (!se->sum_exec_runtime || p->state == TASK_WAKING))
 		on_rq = 1;
 
 	if (!on_rq)
-		p->se.vruntime -= cfs_rq_of(&p->se)->min_vruntime;
+		se->vruntime -= cfs_rq_of(se)->min_vruntime;
 	set_task_rq(p, task_cpu(p));
+	se->depth = se->parent ? se->parent->depth + 1 : 0;
 	if (!on_rq) {
-		cfs_rq = cfs_rq_of(&p->se);
-		p->se.vruntime += cfs_rq->min_vruntime;
+		cfs_rq = cfs_rq_of(se);
+		se->vruntime += cfs_rq->min_vruntime;
 #ifdef CONFIG_SMP
 		/*
 		 * migrate_task_rq_fair() will have removed our previous
 		 * contribution, but we must synchronize for ongoing future
 		 * decay.
 		 */
-		p->se.avg.decay_count = atomic64_read(&cfs_rq->decay_counter);
-		cfs_rq->blocked_load_avg += p->se.avg.load_avg_contrib;
+		se->avg.decay_count = atomic64_read(&cfs_rq->decay_counter);
+		cfs_rq->blocked_load_avg += se->avg.load_avg_contrib;
 #endif
 	}
 }
@@ -7222,10 +7558,13 @@ void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
 	if (!se)
 		return;
 
-	if (!parent)
+	if (!parent) {
 		se->cfs_rq = &rq->cfs;
-	else
+		se->depth = 0;
+	} else {
 		se->cfs_rq = parent->my_q;
+		se->depth = parent->depth + 1;
+	}
 
 	se->my_q = cfs_rq;
 	/* guarantee group entities always have weight */
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
new file mode 100644
index 000000000000..8f4390a079c7
--- /dev/null
+++ b/kernel/sched/idle.c
@@ -0,0 +1,265 @@
+/*
+ * Generic entry point for the idle threads
+ */
+#include <linux/sched.h>
+#include <linux/cpu.h>
+#include <linux/cpuidle.h>
+#include <linux/tick.h>
+#include <linux/mm.h>
+#include <linux/stackprotector.h>
+
+#include <asm/tlb.h>
+
+#include <trace/events/power.h>
+
+static int __read_mostly cpu_idle_force_poll;
+
+void cpu_idle_poll_ctrl(bool enable)
+{
+	if (enable) {
+		cpu_idle_force_poll++;
+	} else {
+		cpu_idle_force_poll--;
+		WARN_ON_ONCE(cpu_idle_force_poll < 0);
+	}
+}
+
+#ifdef CONFIG_GENERIC_IDLE_POLL_SETUP
+static int __init cpu_idle_poll_setup(char *__unused)
+{
+	cpu_idle_force_poll = 1;
+	return 1;
+}
+__setup("nohlt", cpu_idle_poll_setup);
+
+static int __init cpu_idle_nopoll_setup(char *__unused)
+{
+	cpu_idle_force_poll = 0;
+	return 1;
+}
+__setup("hlt", cpu_idle_nopoll_setup);
+#endif
+
+static inline int cpu_idle_poll(void)
+{
+	rcu_idle_enter();
+	trace_cpu_idle_rcuidle(0, smp_processor_id());
+	local_irq_enable();
+	while (!tif_need_resched())
+		cpu_relax();
+	trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id());
+	rcu_idle_exit();
+	return 1;
+}
+
+/* Weak implementations for optional arch specific functions */
+void __weak arch_cpu_idle_prepare(void) { }
+void __weak arch_cpu_idle_enter(void) { }
+void __weak arch_cpu_idle_exit(void) { }
+void __weak arch_cpu_idle_dead(void) { }
+void __weak arch_cpu_idle(void)
+{
+	cpu_idle_force_poll = 1;
+	local_irq_enable();
+}
+
+/**
+ * cpuidle_idle_call - the main idle function
+ *
+ * NOTE: no locks or semaphores should be used here
+ * return non-zero on failure
+ */
+static int cpuidle_idle_call(void)
+{
+	struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices);
+	struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev);
+	int next_state, entered_state, ret;
+	bool broadcast;
+
+	/*
+	 * Check if the idle task must be rescheduled. If it is the
+	 * case, exit the function after re-enabling the local irq and
+	 * set again the polling flag
+	 */
+	if (current_clr_polling_and_test()) {
+		local_irq_enable();
+		__current_set_polling();
+		return 0;
+	}
+
+	/*
+	 * During the idle period, stop measuring the disabled irqs
+	 * critical sections latencies
+	 */
+	stop_critical_timings();
+
+	/*
+	 * Tell the RCU framework we are entering an idle section,
+	 * so no more rcu read side critical sections and one more
+	 * step to the grace period
+	 */
+	rcu_idle_enter();
+
+	/*
+	 * Check if the cpuidle framework is ready, otherwise fallback
+	 * to the default arch specific idle method
+	 */
+	ret = cpuidle_enabled(drv, dev);
+
+	if (!ret) {
+		/*
+		 * Ask the governor to choose an idle state it thinks
+		 * it is convenient to go to. There is *always* a
+		 * convenient idle state
+		 */
+		next_state = cpuidle_select(drv, dev);
+
+		/*
+		 * The idle task must be scheduled, it is pointless to
+		 * go to idle, just update no idle residency and get
+		 * out of this function
+		 */
+		if (current_clr_polling_and_test()) {
+			dev->last_residency = 0;
+			entered_state = next_state;
+			local_irq_enable();
+		} else {
+			broadcast = !!(drv->states[next_state].flags &
+				       CPUIDLE_FLAG_TIMER_STOP);
+
+			if (broadcast)
+				/*
+				 * Tell the time framework to switch
+				 * to a broadcast timer because our
+				 * local timer will be shutdown. If a
+				 * local timer is used from another
+				 * cpu as a broadcast timer, this call
+				 * may fail if it is not available
+				 */
+				ret = clockevents_notify(
+					CLOCK_EVT_NOTIFY_BROADCAST_ENTER,
+					&dev->cpu);
+
+			if (!ret) {
+				trace_cpu_idle_rcuidle(next_state, dev->cpu);
+
+				/*
+				 * Enter the idle state previously
+				 * returned by the governor
+				 * decision. This function will block
+				 * until an interrupt occurs and will
+				 * take care of re-enabling the local
+				 * interrupts
+				 */
+				entered_state = cpuidle_enter(drv, dev,
+							      next_state);
+
+				trace_cpu_idle_rcuidle(PWR_EVENT_EXIT,
+						       dev->cpu);
+
+				if (broadcast)
+					clockevents_notify(
+						CLOCK_EVT_NOTIFY_BROADCAST_EXIT,
+						&dev->cpu);
+
+				/*
+				 * Give the governor an opportunity to reflect on the
+				 * outcome
+				 */
+				cpuidle_reflect(dev, entered_state);
+			}
+		}
+	}
+
+	/*
+	 * We can't use the cpuidle framework, let's use the default
+	 * idle routine
+	 */
+	if (ret)
+		arch_cpu_idle();
+
+	__current_set_polling();
+
+	/*
+	 * It is up to the idle functions to enable back the local
+	 * interrupt
+	 */
+	if (WARN_ON_ONCE(irqs_disabled()))
+		local_irq_enable();
+
+	rcu_idle_exit();
+	start_critical_timings();
+
+	return 0;
+}
+
+/*
+ * Generic idle loop implementation
+ */
+static void cpu_idle_loop(void)
+{
+	while (1) {
+		tick_nohz_idle_enter();
+
+		while (!need_resched()) {
+			check_pgt_cache();
+			rmb();
+
+			if (cpu_is_offline(smp_processor_id()))
+				arch_cpu_idle_dead();
+
+			local_irq_disable();
+			arch_cpu_idle_enter();
+
+			/*
+			 * In poll mode we reenable interrupts and spin.
+			 *
+			 * Also if we detected in the wakeup from idle
+			 * path that the tick broadcast device expired
+			 * for us, we don't want to go deep idle as we
+			 * know that the IPI is going to arrive right
+			 * away
+			 */
+			if (cpu_idle_force_poll || tick_check_broadcast_expired())
+				cpu_idle_poll();
+			else
+				cpuidle_idle_call();
+
+			arch_cpu_idle_exit();
+		}
+
+		/*
+		 * Since we fell out of the loop above, we know
+		 * TIF_NEED_RESCHED must be set, propagate it into
+		 * PREEMPT_NEED_RESCHED.
+		 *
+		 * This is required because for polling idle loops we will
+		 * not have had an IPI to fold the state for us.
+		 */
+		preempt_set_need_resched();
+		tick_nohz_idle_exit();
+		schedule_preempt_disabled();
+	}
+}
+
+void cpu_startup_entry(enum cpuhp_state state)
+{
+	/*
+	 * This #ifdef needs to die, but it's too late in the cycle to
+	 * make this generic (arm and sh have never invoked the canary
+	 * init for the non boot cpus!). Will be fixed in 3.11
+	 */
+#ifdef CONFIG_X86
+	/*
+	 * If we're the non-boot CPU, nothing set the stack canary up
+	 * for us. The boot CPU already has it initialized but no harm
+	 * in doing it again. This is a good place for updating it, as
+	 * we wont ever return from this function (so the invalid
+	 * canaries already on the stack wont ever trigger).
+	 */
+	boot_init_stack_canary();
+#endif
+	__current_set_polling();
+	arch_cpu_idle_prepare();
+	cpu_idle_loop();
+}
diff --git a/kernel/sched/idle_task.c b/kernel/sched/idle_task.c
index 516c3d9ceea1..879f2b75266a 100644
--- a/kernel/sched/idle_task.c
+++ b/kernel/sched/idle_task.c
@@ -13,18 +13,8 @@ select_task_rq_idle(struct task_struct *p, int cpu, int sd_flag, int flags)
 {
 	return task_cpu(p); /* IDLE tasks as never migrated */
 }
-
-static void pre_schedule_idle(struct rq *rq, struct task_struct *prev)
-{
-	idle_exit_fair(rq);
-	rq_last_tick_reset(rq);
-}
-
-static void post_schedule_idle(struct rq *rq)
-{
-	idle_enter_fair(rq);
-}
 #endif /* CONFIG_SMP */
+
 /*
  * Idle tasks are unconditionally rescheduled:
  */
@@ -33,13 +23,12 @@ static void check_preempt_curr_idle(struct rq *rq, struct task_struct *p, int fl
 	resched_task(rq->idle);
 }
 
-static struct task_struct *pick_next_task_idle(struct rq *rq)
+static struct task_struct *
+pick_next_task_idle(struct rq *rq, struct task_struct *prev)
 {
+	put_prev_task(rq, prev);
+
 	schedstat_inc(rq, sched_goidle);
-#ifdef CONFIG_SMP
-	/* Trigger the post schedule to do an idle_enter for CFS */
-	rq->post_schedule = 1;
-#endif
 	return rq->idle;
 }
 
@@ -58,6 +47,8 @@ dequeue_task_idle(struct rq *rq, struct task_struct *p, int flags)
 
 static void put_prev_task_idle(struct rq *rq, struct task_struct *prev)
 {
+	idle_exit_fair(rq);
+	rq_last_tick_reset(rq);
 }
 
 static void task_tick_idle(struct rq *rq, struct task_struct *curr, int queued)
@@ -101,8 +92,6 @@ const struct sched_class idle_sched_class = {
 
 #ifdef CONFIG_SMP
 	.select_task_rq		= select_task_rq_idle,
-	.pre_schedule		= pre_schedule_idle,
-	.post_schedule		= post_schedule_idle,
 #endif
 
 	.set_curr_task          = set_curr_task_idle,
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 1999021042c7..bd2267ad404f 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -229,6 +229,14 @@ int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent)
 
 #ifdef CONFIG_SMP
 
+static int pull_rt_task(struct rq *this_rq);
+
+static inline bool need_pull_rt_task(struct rq *rq, struct task_struct *prev)
+{
+	/* Try to pull RT tasks here if we lower this rq's prio */
+	return rq->rt.highest_prio.curr > prev->prio;
+}
+
 static inline int rt_overloaded(struct rq *rq)
 {
 	return atomic_read(&rq->rd->rto_count);
@@ -315,6 +323,15 @@ static inline int has_pushable_tasks(struct rq *rq)
 	return !plist_head_empty(&rq->rt.pushable_tasks);
 }
 
+static inline void set_post_schedule(struct rq *rq)
+{
+	/*
+	 * We detect this state here so that we can avoid taking the RQ
+	 * lock again later if there is no need to push
+	 */
+	rq->post_schedule = has_pushable_tasks(rq);
+}
+
 static void enqueue_pushable_task(struct rq *rq, struct task_struct *p)
 {
 	plist_del(&p->pushable_tasks, &rq->rt.pushable_tasks);
@@ -359,6 +376,19 @@ void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
 {
 }
 
+static inline bool need_pull_rt_task(struct rq *rq, struct task_struct *prev)
+{
+	return false;
+}
+
+static inline int pull_rt_task(struct rq *this_rq)
+{
+	return 0;
+}
+
+static inline void set_post_schedule(struct rq *rq)
+{
+}
 #endif /* CONFIG_SMP */
 
 static inline int on_rt_rq(struct sched_rt_entity *rt_se)
@@ -440,11 +470,6 @@ static void sched_rt_rq_dequeue(struct rt_rq *rt_rq)
 		dequeue_rt_entity(rt_se);
 }
 
-static inline int rt_rq_throttled(struct rt_rq *rt_rq)
-{
-	return rt_rq->rt_throttled && !rt_rq->rt_nr_boosted;
-}
-
 static int rt_se_boosted(struct sched_rt_entity *rt_se)
 {
 	struct rt_rq *rt_rq = group_rt_rq(rt_se);
@@ -515,11 +540,6 @@ static inline void sched_rt_rq_dequeue(struct rt_rq *rt_rq)
 {
 }
 
-static inline int rt_rq_throttled(struct rt_rq *rt_rq)
-{
-	return rt_rq->rt_throttled;
-}
-
 static inline const struct cpumask *sched_rt_period_mask(void)
 {
 	return cpu_online_mask;
@@ -1318,15 +1338,7 @@ static struct task_struct *_pick_next_task_rt(struct rq *rq)
 {
 	struct sched_rt_entity *rt_se;
 	struct task_struct *p;
-	struct rt_rq *rt_rq;
-
-	rt_rq = &rq->rt;
-
-	if (!rt_rq->rt_nr_running)
-		return NULL;
-
-	if (rt_rq_throttled(rt_rq))
-		return NULL;
+	struct rt_rq *rt_rq  = &rq->rt;
 
 	do {
 		rt_se = pick_next_rt_entity(rq, rt_rq);
@@ -1340,21 +1352,46 @@ static struct task_struct *_pick_next_task_rt(struct rq *rq)
 	return p;
 }
 
-static struct task_struct *pick_next_task_rt(struct rq *rq)
+static struct task_struct *
+pick_next_task_rt(struct rq *rq, struct task_struct *prev)
 {
-	struct task_struct *p = _pick_next_task_rt(rq);
+	struct task_struct *p;
+	struct rt_rq *rt_rq = &rq->rt;
+
+	if (need_pull_rt_task(rq, prev)) {
+		pull_rt_task(rq);
+		/*
+		 * pull_rt_task() can drop (and re-acquire) rq->lock; this
+		 * means a dl or stop task can slip in, in which case we need
+		 * to re-start task selection.
+		 */
+		if (unlikely((rq->stop && rq->stop->on_rq) ||
+			     rq->dl.dl_nr_running))
+			return RETRY_TASK;
+	}
+
+	/*
+	 * We may dequeue prev's rt_rq in put_prev_task().
+	 * So, we update time before rt_nr_running check.
+	 */
+	if (prev->sched_class == &rt_sched_class)
+		update_curr_rt(rq);
+
+	if (!rt_rq->rt_nr_running)
+		return NULL;
+
+	if (rt_rq_throttled(rt_rq))
+		return NULL;
+
+	put_prev_task(rq, prev);
+
+	p = _pick_next_task_rt(rq);
 
 	/* The running task is never eligible for pushing */
 	if (p)
 		dequeue_pushable_task(rq, p);
 
-#ifdef CONFIG_SMP
-	/*
-	 * We detect this state here so that we can avoid taking the RQ
-	 * lock again later if there is no need to push
-	 */
-	rq->post_schedule = has_pushable_tasks(rq);
-#endif
+	set_post_schedule(rq);
 
 	return p;
 }
@@ -1724,13 +1761,6 @@ skip:
 	return ret;
 }
 
-static void pre_schedule_rt(struct rq *rq, struct task_struct *prev)
-{
-	/* Try to pull RT tasks here if we lower this rq's prio */
-	if (rq->rt.highest_prio.curr > prev->prio)
-		pull_rt_task(rq);
-}
-
 static void post_schedule_rt(struct rq *rq)
 {
 	push_rt_tasks(rq);
@@ -1833,7 +1863,7 @@ static void switched_from_rt(struct rq *rq, struct task_struct *p)
 		resched_task(rq->curr);
 }
 
-void init_sched_rt_class(void)
+void __init init_sched_rt_class(void)
 {
 	unsigned int i;
 
@@ -2007,7 +2037,6 @@ const struct sched_class rt_sched_class = {
 	.set_cpus_allowed       = set_cpus_allowed_rt,
 	.rq_online              = rq_online_rt,
 	.rq_offline             = rq_offline_rt,
-	.pre_schedule		= pre_schedule_rt,
 	.post_schedule		= post_schedule_rt,
 	.task_woken		= task_woken_rt,
 	.switched_from		= switched_from_rt,
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index f964add50f38..369b4d663c42 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -24,24 +24,6 @@ extern long calc_load_fold_active(struct rq *this_rq);
 extern void update_cpu_load_active(struct rq *this_rq);
 
 /*
- * Convert user-nice values [ -20 ... 0 ... 19 ]
- * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
- * and back.
- */
-#define NICE_TO_PRIO(nice)	(MAX_RT_PRIO + (nice) + 20)
-#define PRIO_TO_NICE(prio)	((prio) - MAX_RT_PRIO - 20)
-#define TASK_NICE(p)		PRIO_TO_NICE((p)->static_prio)
-
-/*
- * 'User priority' is the nice value converted to something we
- * can work with better when scaling various scheduler parameters,
- * it's a [ 0 ... 39 ] range.
- */
-#define USER_PRIO(p)		((p)-MAX_RT_PRIO)
-#define TASK_USER_PRIO(p)	USER_PRIO((p)->static_prio)
-#define MAX_USER_PRIO		(USER_PRIO(MAX_PRIO))
-
-/*
  * Helpers for converting nanosecond timing to jiffy resolution
  */
 #define NS_TO_JIFFIES(TIME)	((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
@@ -296,7 +278,7 @@ extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
 
 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
-extern void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
+extern void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b, bool force);
 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
 
 extern void free_rt_sched_group(struct task_group *tg);
@@ -441,6 +423,18 @@ struct rt_rq {
 #endif
 };
 
+#ifdef CONFIG_RT_GROUP_SCHED
+static inline int rt_rq_throttled(struct rt_rq *rt_rq)
+{
+	return rt_rq->rt_throttled && !rt_rq->rt_nr_boosted;
+}
+#else
+static inline int rt_rq_throttled(struct rt_rq *rt_rq)
+{
+	return rt_rq->rt_throttled;
+}
+#endif
+
 /* Deadline class' related fields in a runqueue */
 struct dl_rq {
 	/* runqueue is an rbtree, ordered by deadline */
@@ -558,11 +552,9 @@ struct rq {
 #ifdef CONFIG_FAIR_GROUP_SCHED
 	/* list of leaf cfs_rq on this cpu: */
 	struct list_head leaf_cfs_rq_list;
-#endif /* CONFIG_FAIR_GROUP_SCHED */
 
-#ifdef CONFIG_RT_GROUP_SCHED
-	struct list_head leaf_rt_rq_list;
-#endif
+	struct sched_avg avg;
+#endif /* CONFIG_FAIR_GROUP_SCHED */
 
 	/*
 	 * This is part of a global counter where only the total sum
@@ -651,8 +643,6 @@ struct rq {
 #ifdef CONFIG_SMP
 	struct llist_head wake_list;
 #endif
-
-	struct sched_avg avg;
 };
 
 static inline int cpu_of(struct rq *rq)
@@ -1112,6 +1102,8 @@ static const u32 prio_to_wmult[40] = {
 
 #define DEQUEUE_SLEEP		1
 
+#define RETRY_TASK		((void *)-1UL)
+
 struct sched_class {
 	const struct sched_class *next;
 
@@ -1122,14 +1114,22 @@ struct sched_class {
 
 	void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
 
-	struct task_struct * (*pick_next_task) (struct rq *rq);
+	/*
+	 * It is the responsibility of the pick_next_task() method that will
+	 * return the next task to call put_prev_task() on the @prev task or
+	 * something equivalent.
+	 *
+	 * May return RETRY_TASK when it finds a higher prio class has runnable
+	 * tasks.
+	 */
+	struct task_struct * (*pick_next_task) (struct rq *rq,
+						struct task_struct *prev);
 	void (*put_prev_task) (struct rq *rq, struct task_struct *p);
 
 #ifdef CONFIG_SMP
 	int  (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
 	void (*migrate_task_rq)(struct task_struct *p, int next_cpu);
 
-	void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
 	void (*post_schedule) (struct rq *this_rq);
 	void (*task_waking) (struct task_struct *task);
 	void (*task_woken) (struct rq *this_rq, struct task_struct *task);
@@ -1159,6 +1159,11 @@ struct sched_class {
 #endif
 };
 
+static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
+{
+	prev->sched_class->put_prev_task(rq, prev);
+}
+
 #define sched_class_highest (&stop_sched_class)
 #define for_each_class(class) \
    for (class = sched_class_highest; class; class = class->next)
@@ -1175,16 +1180,14 @@ extern const struct sched_class idle_sched_class;
 extern void update_group_power(struct sched_domain *sd, int cpu);
 
 extern void trigger_load_balance(struct rq *rq);
-extern void idle_balance(int this_cpu, struct rq *this_rq);
 
 extern void idle_enter_fair(struct rq *this_rq);
 extern void idle_exit_fair(struct rq *this_rq);
 
-#else	/* CONFIG_SMP */
+#else
 
-static inline void idle_balance(int cpu, struct rq *rq)
-{
-}
+static inline void idle_enter_fair(struct rq *rq) { }
+static inline void idle_exit_fair(struct rq *rq) { }
 
 #endif
 
@@ -1213,16 +1216,6 @@ extern void update_idle_cpu_load(struct rq *this_rq);
 
 extern void init_task_runnable_average(struct task_struct *p);
 
-#ifdef CONFIG_PARAVIRT
-static inline u64 steal_ticks(u64 steal)
-{
-	if (unlikely(steal > NSEC_PER_SEC))
-		return div_u64(steal, TICK_NSEC);
-
-	return __iter_div_u64_rem(steal, TICK_NSEC, &steal);
-}
-#endif
-
 static inline void inc_nr_running(struct rq *rq)
 {
 	rq->nr_running++;
@@ -1392,6 +1385,15 @@ static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
 	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
 }
 
+static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
+{
+	if (l1 > l2)
+		swap(l1, l2);
+
+	spin_lock_irq(l1);
+	spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
+}
+
 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
 {
 	if (l1 > l2)
diff --git a/kernel/sched/stats.c b/kernel/sched/stats.c
index da98af347e8b..a476bea17fbc 100644
--- a/kernel/sched/stats.c
+++ b/kernel/sched/stats.c
@@ -142,4 +142,4 @@ static int __init proc_schedstat_init(void)
 	proc_create("schedstat", 0, NULL, &proc_schedstat_operations);
 	return 0;
 }
-module_init(proc_schedstat_init);
+subsys_initcall(proc_schedstat_init);
diff --git a/kernel/sched/stop_task.c b/kernel/sched/stop_task.c
index fdb6bb0b3356..d6ce65dde541 100644
--- a/kernel/sched/stop_task.c
+++ b/kernel/sched/stop_task.c
@@ -23,16 +23,19 @@ check_preempt_curr_stop(struct rq *rq, struct task_struct *p, int flags)
 	/* we're never preempted */
 }
 
-static struct task_struct *pick_next_task_stop(struct rq *rq)
+static struct task_struct *
+pick_next_task_stop(struct rq *rq, struct task_struct *prev)
 {
 	struct task_struct *stop = rq->stop;
 
-	if (stop && stop->on_rq) {
-		stop->se.exec_start = rq_clock_task(rq);
-		return stop;
-	}
+	if (!stop || !stop->on_rq)
+		return NULL;
 
-	return NULL;
+	put_prev_task(rq, prev);
+
+	stop->se.exec_start = rq_clock_task(rq);
+
+	return stop;
 }
 
 static void
diff --git a/kernel/seccomp.c b/kernel/seccomp.c
index 0e004a70f63a..b35c21503a36 100644
--- a/kernel/seccomp.c
+++ b/kernel/seccomp.c
@@ -55,60 +55,32 @@ struct seccomp_filter {
 	atomic_t usage;
 	struct seccomp_filter *prev;
 	unsigned short len;  /* Instruction count */
-	struct sock_filter insns[];
+	struct sock_filter_int insnsi[];
 };
 
 /* Limit any path through the tree to 256KB worth of instructions. */
 #define MAX_INSNS_PER_PATH ((1 << 18) / sizeof(struct sock_filter))
 
-/**
- * get_u32 - returns a u32 offset into data
- * @data: a unsigned 64 bit value
- * @index: 0 or 1 to return the first or second 32-bits
- *
- * This inline exists to hide the length of unsigned long.  If a 32-bit
- * unsigned long is passed in, it will be extended and the top 32-bits will be
- * 0. If it is a 64-bit unsigned long, then whatever data is resident will be
- * properly returned.
- *
+/*
  * Endianness is explicitly ignored and left for BPF program authors to manage
  * as per the specific architecture.
  */
-static inline u32 get_u32(u64 data, int index)
-{
-	return ((u32 *)&data)[index];
-}
-
-/* Helper for bpf_load below. */
-#define BPF_DATA(_name) offsetof(struct seccomp_data, _name)
-/**
- * bpf_load: checks and returns a pointer to the requested offset
- * @off: offset into struct seccomp_data to load from
- *
- * Returns the requested 32-bits of data.
- * seccomp_check_filter() should assure that @off is 32-bit aligned
- * and not out of bounds.  Failure to do so is a BUG.
- */
-u32 seccomp_bpf_load(int off)
+static void populate_seccomp_data(struct seccomp_data *sd)
 {
-	struct pt_regs *regs = task_pt_regs(current);
-	if (off == BPF_DATA(nr))
-		return syscall_get_nr(current, regs);
-	if (off == BPF_DATA(arch))
-		return syscall_get_arch(current, regs);
-	if (off >= BPF_DATA(args[0]) && off < BPF_DATA(args[6])) {
-		unsigned long value;
-		int arg = (off - BPF_DATA(args[0])) / sizeof(u64);
-		int index = !!(off % sizeof(u64));
-		syscall_get_arguments(current, regs, arg, 1, &value);
-		return get_u32(value, index);
-	}
-	if (off == BPF_DATA(instruction_pointer))
-		return get_u32(KSTK_EIP(current), 0);
-	if (off == BPF_DATA(instruction_pointer) + sizeof(u32))
-		return get_u32(KSTK_EIP(current), 1);
-	/* seccomp_check_filter should make this impossible. */
-	BUG();
+	struct task_struct *task = current;
+	struct pt_regs *regs = task_pt_regs(task);
+	unsigned long args[6];
+
+	sd->nr = syscall_get_nr(task, regs);
+	sd->arch = syscall_get_arch();
+	syscall_get_arguments(task, regs, 0, 6, args);
+	sd->args[0] = args[0];
+	sd->args[1] = args[1];
+	sd->args[2] = args[2];
+	sd->args[3] = args[3];
+	sd->args[4] = args[4];
+	sd->args[5] = args[5];
+	sd->instruction_pointer = KSTK_EIP(task);
 }
 
 /**
@@ -133,17 +105,17 @@ static int seccomp_check_filter(struct sock_filter *filter, unsigned int flen)
 
 		switch (code) {
 		case BPF_S_LD_W_ABS:
-			ftest->code = BPF_S_ANC_SECCOMP_LD_W;
+			ftest->code = BPF_LDX | BPF_W | BPF_ABS;
 			/* 32-bit aligned and not out of bounds. */
 			if (k >= sizeof(struct seccomp_data) || k & 3)
 				return -EINVAL;
 			continue;
 		case BPF_S_LD_W_LEN:
-			ftest->code = BPF_S_LD_IMM;
+			ftest->code = BPF_LD | BPF_IMM;
 			ftest->k = sizeof(struct seccomp_data);
 			continue;
 		case BPF_S_LDX_W_LEN:
-			ftest->code = BPF_S_LDX_IMM;
+			ftest->code = BPF_LDX | BPF_IMM;
 			ftest->k = sizeof(struct seccomp_data);
 			continue;
 		/* Explicitly include allowed calls. */
@@ -185,6 +157,7 @@ static int seccomp_check_filter(struct sock_filter *filter, unsigned int flen)
 		case BPF_S_JMP_JGT_X:
 		case BPF_S_JMP_JSET_K:
 		case BPF_S_JMP_JSET_X:
+			sk_decode_filter(ftest, ftest);
 			continue;
 		default:
 			return -EINVAL;
@@ -202,18 +175,21 @@ static int seccomp_check_filter(struct sock_filter *filter, unsigned int flen)
 static u32 seccomp_run_filters(int syscall)
 {
 	struct seccomp_filter *f;
+	struct seccomp_data sd;
 	u32 ret = SECCOMP_RET_ALLOW;
 
 	/* Ensure unexpected behavior doesn't result in failing open. */
 	if (WARN_ON(current->seccomp.filter == NULL))
 		return SECCOMP_RET_KILL;
 
+	populate_seccomp_data(&sd);
+
 	/*
 	 * All filters in the list are evaluated and the lowest BPF return
 	 * value always takes priority (ignoring the DATA).
 	 */
 	for (f = current->seccomp.filter; f; f = f->prev) {
-		u32 cur_ret = sk_run_filter(NULL, f->insns);
+		u32 cur_ret = sk_run_filter_int_seccomp(&sd, f->insnsi);
 		if ((cur_ret & SECCOMP_RET_ACTION) < (ret & SECCOMP_RET_ACTION))
 			ret = cur_ret;
 	}
@@ -231,6 +207,8 @@ static long seccomp_attach_filter(struct sock_fprog *fprog)
 	struct seccomp_filter *filter;
 	unsigned long fp_size = fprog->len * sizeof(struct sock_filter);
 	unsigned long total_insns = fprog->len;
+	struct sock_filter *fp;
+	int new_len;
 	long ret;
 
 	if (fprog->len == 0 || fprog->len > BPF_MAXINSNS)
@@ -252,28 +230,45 @@ static long seccomp_attach_filter(struct sock_fprog *fprog)
 				     CAP_SYS_ADMIN) != 0)
 		return -EACCES;
 
-	/* Allocate a new seccomp_filter */
-	filter = kzalloc(sizeof(struct seccomp_filter) + fp_size,
-			 GFP_KERNEL|__GFP_NOWARN);
-	if (!filter)
+	fp = kzalloc(fp_size, GFP_KERNEL|__GFP_NOWARN);
+	if (!fp)
 		return -ENOMEM;
-	atomic_set(&filter->usage, 1);
-	filter->len = fprog->len;
 
 	/* Copy the instructions from fprog. */
 	ret = -EFAULT;
-	if (copy_from_user(filter->insns, fprog->filter, fp_size))
-		goto fail;
+	if (copy_from_user(fp, fprog->filter, fp_size))
+		goto free_prog;
 
 	/* Check and rewrite the fprog via the skb checker */
-	ret = sk_chk_filter(filter->insns, filter->len);
+	ret = sk_chk_filter(fp, fprog->len);
 	if (ret)
-		goto fail;
+		goto free_prog;
 
 	/* Check and rewrite the fprog for seccomp use */
-	ret = seccomp_check_filter(filter->insns, filter->len);
+	ret = seccomp_check_filter(fp, fprog->len);
+	if (ret)
+		goto free_prog;
+
+	/* Convert 'sock_filter' insns to 'sock_filter_int' insns */
+	ret = sk_convert_filter(fp, fprog->len, NULL, &new_len);
 	if (ret)
-		goto fail;
+		goto free_prog;
+
+	/* Allocate a new seccomp_filter */
+	ret = -ENOMEM;
+	filter = kzalloc(sizeof(struct seccomp_filter) +
+			 sizeof(struct sock_filter_int) * new_len,
+			 GFP_KERNEL|__GFP_NOWARN);
+	if (!filter)
+		goto free_prog;
+
+	ret = sk_convert_filter(fp, fprog->len, filter->insnsi, &new_len);
+	if (ret)
+		goto free_filter;
+	kfree(fp);
+
+	atomic_set(&filter->usage, 1);
+	filter->len = new_len;
 
 	/*
 	 * If there is an existing filter, make it the prev and don't drop its
@@ -282,8 +277,11 @@ static long seccomp_attach_filter(struct sock_fprog *fprog)
 	filter->prev = current->seccomp.filter;
 	current->seccomp.filter = filter;
 	return 0;
-fail:
+
+free_filter:
 	kfree(filter);
+free_prog:
+	kfree(fp);
 	return ret;
 }
 
@@ -351,7 +349,7 @@ static void seccomp_send_sigsys(int syscall, int reason)
 	info.si_code = SYS_SECCOMP;
 	info.si_call_addr = (void __user *)KSTK_EIP(current);
 	info.si_errno = reason;
-	info.si_arch = syscall_get_arch(current, task_pt_regs(current));
+	info.si_arch = syscall_get_arch();
 	info.si_syscall = syscall;
 	force_sig_info(SIGSYS, &info, current);
 }
diff --git a/kernel/signal.c b/kernel/signal.c
index 52f881db1ca0..6ea13c09ae56 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -33,6 +33,8 @@
 #include <linux/uprobes.h>
 #include <linux/compat.h>
 #include <linux/cn_proc.h>
+#include <linux/compiler.h>
+
 #define CREATE_TRACE_POINTS
 #include <trace/events/signal.h>
 
@@ -2382,7 +2384,7 @@ relock:
  * @regs:		user register state
  * @stepping:		nonzero if debugger single-step or block-step in use
  *
- * This function should be called when a signal has succesfully been
+ * This function should be called when a signal has successfully been
  * delivered. It updates the blocked signals accordingly (@ka->sa.sa_mask
  * is always blocked, and the signal itself is blocked unless %SA_NODEFER
  * is set in @ka->sa.sa_flags.  Tracing is notified.
@@ -3618,7 +3620,7 @@ SYSCALL_DEFINE3(sigsuspend, int, unused1, int, unused2, old_sigset_t, mask)
 }
 #endif
 
-__attribute__((weak)) const char *arch_vma_name(struct vm_area_struct *vma)
+__weak const char *arch_vma_name(struct vm_area_struct *vma)
 {
 	return NULL;
 }
diff --git a/kernel/smp.c b/kernel/smp.c
index ffee35bef179..06d574e42c72 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -117,13 +117,43 @@ static void csd_unlock(struct call_single_data *csd)
 	csd->flags &= ~CSD_FLAG_LOCK;
 }
 
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_single_data, csd_data);
+
 /*
  * Insert a previously allocated call_single_data element
  * for execution on the given CPU. data must already have
  * ->func, ->info, and ->flags set.
  */
-static void generic_exec_single(int cpu, struct call_single_data *csd, int wait)
+static int generic_exec_single(int cpu, struct call_single_data *csd,
+			       smp_call_func_t func, void *info, int wait)
 {
+	struct call_single_data csd_stack = { .flags = 0 };
+	unsigned long flags;
+
+
+	if (cpu == smp_processor_id()) {
+		local_irq_save(flags);
+		func(info);
+		local_irq_restore(flags);
+		return 0;
+	}
+
+
+	if ((unsigned)cpu >= nr_cpu_ids || !cpu_online(cpu))
+		return -ENXIO;
+
+
+	if (!csd) {
+		csd = &csd_stack;
+		if (!wait)
+			csd = &__get_cpu_var(csd_data);
+	}
+
+	csd_lock(csd);
+
+	csd->func = func;
+	csd->info = info;
+
 	if (wait)
 		csd->flags |= CSD_FLAG_WAIT;
 
@@ -143,6 +173,8 @@ static void generic_exec_single(int cpu, struct call_single_data *csd, int wait)
 
 	if (wait)
 		csd_lock_wait(csd);
+
+	return 0;
 }
 
 /*
@@ -151,7 +183,8 @@ static void generic_exec_single(int cpu, struct call_single_data *csd, int wait)
  */
 void generic_smp_call_function_single_interrupt(void)
 {
-	struct llist_node *entry, *next;
+	struct llist_node *entry;
+	struct call_single_data *csd, *csd_next;
 
 	/*
 	 * Shouldn't receive this interrupt on a cpu that is not yet online.
@@ -161,21 +194,12 @@ void generic_smp_call_function_single_interrupt(void)
 	entry = llist_del_all(&__get_cpu_var(call_single_queue));
 	entry = llist_reverse_order(entry);
 
-	while (entry) {
-		struct call_single_data *csd;
-
-		next = entry->next;
-
-		csd = llist_entry(entry, struct call_single_data, llist);
+	llist_for_each_entry_safe(csd, csd_next, entry, llist) {
 		csd->func(csd->info);
 		csd_unlock(csd);
-
-		entry = next;
 	}
 }
 
-static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_single_data, csd_data);
-
 /*
  * smp_call_function_single - Run a function on a specific CPU
  * @func: The function to run. This must be fast and non-blocking.
@@ -187,12 +211,8 @@ static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_single_data, csd_data);
 int smp_call_function_single(int cpu, smp_call_func_t func, void *info,
 			     int wait)
 {
-	struct call_single_data d = {
-		.flags = 0,
-	};
-	unsigned long flags;
 	int this_cpu;
-	int err = 0;
+	int err;
 
 	/*
 	 * prevent preemption and reschedule on another processor,
@@ -209,32 +229,41 @@ int smp_call_function_single(int cpu, smp_call_func_t func, void *info,
 	WARN_ON_ONCE(cpu_online(this_cpu) && irqs_disabled()
 		     && !oops_in_progress);
 
-	if (cpu == this_cpu) {
-		local_irq_save(flags);
-		func(info);
-		local_irq_restore(flags);
-	} else {
-		if ((unsigned)cpu < nr_cpu_ids && cpu_online(cpu)) {
-			struct call_single_data *csd = &d;
+	err = generic_exec_single(cpu, NULL, func, info, wait);
 
-			if (!wait)
-				csd = &__get_cpu_var(csd_data);
+	put_cpu();
 
-			csd_lock(csd);
+	return err;
+}
+EXPORT_SYMBOL(smp_call_function_single);
 
-			csd->func = func;
-			csd->info = info;
-			generic_exec_single(cpu, csd, wait);
-		} else {
-			err = -ENXIO;	/* CPU not online */
-		}
-	}
+/**
+ * smp_call_function_single_async(): Run an asynchronous function on a
+ * 			         specific CPU.
+ * @cpu: The CPU to run on.
+ * @csd: Pre-allocated and setup data structure
+ *
+ * Like smp_call_function_single(), but the call is asynchonous and
+ * can thus be done from contexts with disabled interrupts.
+ *
+ * The caller passes his own pre-allocated data structure
+ * (ie: embedded in an object) and is responsible for synchronizing it
+ * such that the IPIs performed on the @csd are strictly serialized.
+ *
+ * NOTE: Be careful, there is unfortunately no current debugging facility to
+ * validate the correctness of this serialization.
+ */
+int smp_call_function_single_async(int cpu, struct call_single_data *csd)
+{
+	int err = 0;
 
-	put_cpu();
+	preempt_disable();
+	err = generic_exec_single(cpu, csd, csd->func, csd->info, 0);
+	preempt_enable();
 
 	return err;
 }
-EXPORT_SYMBOL(smp_call_function_single);
+EXPORT_SYMBOL_GPL(smp_call_function_single_async);
 
 /*
  * smp_call_function_any - Run a function on any of the given cpus
@@ -280,44 +309,6 @@ call:
 EXPORT_SYMBOL_GPL(smp_call_function_any);
 
 /**
- * __smp_call_function_single(): Run a function on a specific CPU
- * @cpu: The CPU to run on.
- * @data: Pre-allocated and setup data structure
- * @wait: If true, wait until function has completed on specified CPU.
- *
- * Like smp_call_function_single(), but allow caller to pass in a
- * pre-allocated data structure. Useful for embedding @data inside
- * other structures, for instance.
- */
-void __smp_call_function_single(int cpu, struct call_single_data *csd,
-				int wait)
-{
-	unsigned int this_cpu;
-	unsigned long flags;
-
-	this_cpu = get_cpu();
-	/*
-	 * Can deadlock when called with interrupts disabled.
-	 * We allow cpu's that are not yet online though, as no one else can
-	 * send smp call function interrupt to this cpu and as such deadlocks
-	 * can't happen.
-	 */
-	WARN_ON_ONCE(cpu_online(smp_processor_id()) && wait && irqs_disabled()
-		     && !oops_in_progress);
-
-	if (cpu == this_cpu) {
-		local_irq_save(flags);
-		csd->func(csd->info);
-		local_irq_restore(flags);
-	} else {
-		csd_lock(csd);
-		generic_exec_single(cpu, csd, wait);
-	}
-	put_cpu();
-}
-EXPORT_SYMBOL_GPL(__smp_call_function_single);
-
-/**
  * smp_call_function_many(): Run a function on a set of other CPUs.
  * @mask: The set of cpus to run on (only runs on online subset).
  * @func: The function to run. This must be fast and non-blocking.
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 490fcbb1dc5b..92f24f5e8d52 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -25,6 +25,7 @@
 #include <linux/smp.h>
 #include <linux/smpboot.h>
 #include <linux/tick.h>
+#include <linux/irq.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/irq.h>
@@ -222,7 +223,7 @@ static inline bool lockdep_softirq_start(void) { return false; }
 static inline void lockdep_softirq_end(bool in_hardirq) { }
 #endif
 
-asmlinkage void __do_softirq(void)
+asmlinkage __visible void __do_softirq(void)
 {
 	unsigned long end = jiffies + MAX_SOFTIRQ_TIME;
 	unsigned long old_flags = current->flags;
@@ -298,7 +299,7 @@ restart:
 	tsk_restore_flags(current, old_flags, PF_MEMALLOC);
 }
 
-asmlinkage void do_softirq(void)
+asmlinkage __visible void do_softirq(void)
 {
 	__u32 pending;
 	unsigned long flags;
@@ -778,3 +779,8 @@ int __init __weak arch_early_irq_init(void)
 {
 	return 0;
 }
+
+unsigned int __weak arch_dynirq_lower_bound(unsigned int from)
+{
+	return from;
+}
diff --git a/kernel/sys.c b/kernel/sys.c
index c0a58be780a4..fba0f29401ea 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -174,10 +174,10 @@ SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval)
 
 	/* normalize: avoid signed division (rounding problems) */
 	error = -ESRCH;
-	if (niceval < -20)
-		niceval = -20;
-	if (niceval > 19)
-		niceval = 19;
+	if (niceval < MIN_NICE)
+		niceval = MIN_NICE;
+	if (niceval > MAX_NICE)
+		niceval = MAX_NICE;
 
 	rcu_read_lock();
 	read_lock(&tasklist_lock);
@@ -1996,6 +1996,21 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
 		if (arg2 || arg3 || arg4 || arg5)
 			return -EINVAL;
 		return current->no_new_privs ? 1 : 0;
+	case PR_GET_THP_DISABLE:
+		if (arg2 || arg3 || arg4 || arg5)
+			return -EINVAL;
+		error = !!(me->mm->def_flags & VM_NOHUGEPAGE);
+		break;
+	case PR_SET_THP_DISABLE:
+		if (arg3 || arg4 || arg5)
+			return -EINVAL;
+		down_write(&me->mm->mmap_sem);
+		if (arg2)
+			me->mm->def_flags |= VM_NOHUGEPAGE;
+		else
+			me->mm->def_flags &= ~VM_NOHUGEPAGE;
+		up_write(&me->mm->mmap_sem);
+		break;
 	default:
 		error = -EINVAL;
 		break;
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index 7078052284fd..bc8d1b74a6b9 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -146,11 +146,13 @@ cond_syscall(sys_io_destroy);
 cond_syscall(sys_io_submit);
 cond_syscall(sys_io_cancel);
 cond_syscall(sys_io_getevents);
+cond_syscall(sys_sysfs);
 cond_syscall(sys_syslog);
 cond_syscall(sys_process_vm_readv);
 cond_syscall(sys_process_vm_writev);
 cond_syscall(compat_sys_process_vm_readv);
 cond_syscall(compat_sys_process_vm_writev);
+cond_syscall(sys_uselib);
 
 /* arch-specific weak syscall entries */
 cond_syscall(sys_pciconfig_read);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 49e13e1f8fe6..74f5b580fe34 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -112,9 +112,6 @@ extern int sysctl_nr_open_min, sysctl_nr_open_max;
 #ifndef CONFIG_MMU
 extern int sysctl_nr_trim_pages;
 #endif
-#ifdef CONFIG_BLOCK
-extern int blk_iopoll_enabled;
-#endif
 
 /* Constants used for minimum and  maximum */
 #ifdef CONFIG_LOCKUP_DETECTOR
@@ -126,7 +123,7 @@ static int __maybe_unused neg_one = -1;
 static int zero;
 static int __maybe_unused one = 1;
 static int __maybe_unused two = 2;
-static int __maybe_unused three = 3;
+static int __maybe_unused four = 4;
 static unsigned long one_ul = 1;
 static int one_hundred = 100;
 #ifdef CONFIG_PRINTK
@@ -144,6 +141,11 @@ static int min_percpu_pagelist_fract = 8;
 static int ngroups_max = NGROUPS_MAX;
 static const int cap_last_cap = CAP_LAST_CAP;
 
+/*this is needed for proc_doulongvec_minmax of sysctl_hung_task_timeout_secs */
+#ifdef CONFIG_DETECT_HUNG_TASK
+static unsigned long hung_task_timeout_max = (LONG_MAX/HZ);
+#endif
+
 #ifdef CONFIG_INOTIFY_USER
 #include <linux/inotify.h>
 #endif
@@ -386,13 +388,6 @@ static struct ctl_table kern_table[] = {
 		.proc_handler	= proc_dointvec,
 	},
 	{
-		.procname       = "numa_balancing_migrate_deferred",
-		.data           = &sysctl_numa_balancing_migrate_deferred,
-		.maxlen         = sizeof(unsigned int),
-		.mode           = 0644,
-		.proc_handler   = proc_dointvec,
-	},
-	{
 		.procname	= "numa_balancing",
 		.data		= NULL, /* filled in by handler */
 		.maxlen		= sizeof(unsigned int),
@@ -995,6 +990,7 @@ static struct ctl_table kern_table[] = {
 		.maxlen		= sizeof(unsigned long),
 		.mode		= 0644,
 		.proc_handler	= proc_dohung_task_timeout_secs,
+		.extra2		= &hung_task_timeout_max,
 	},
 	{
 		.procname	= "hung_task_warnings",
@@ -1094,15 +1090,6 @@ static struct ctl_table kern_table[] = {
 		.proc_handler	= proc_dointvec,
 	},
 #endif
-#ifdef CONFIG_BLOCK
-	{
-		.procname	= "blk_iopoll",
-		.data		= &blk_iopoll_enabled,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
-	},
-#endif
 	{ }
 };
 
@@ -1283,7 +1270,7 @@ static struct ctl_table vm_table[] = {
 		.mode		= 0644,
 		.proc_handler	= drop_caches_sysctl_handler,
 		.extra1		= &one,
-		.extra2		= &three,
+		.extra2		= &four,
 	},
 #ifdef CONFIG_COMPACTION
 	{
diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig
index 3ce6e8c5f3fc..f448513a45ed 100644
--- a/kernel/time/Kconfig
+++ b/kernel/time/Kconfig
@@ -124,7 +124,7 @@ config NO_HZ_FULL
 endchoice
 
 config NO_HZ_FULL_ALL
-       bool "Full dynticks system on all CPUs by default"
+       bool "Full dynticks system on all CPUs by default (except CPU 0)"
        depends on NO_HZ_FULL
        help
          If the user doesn't pass the nohz_full boot option to
diff --git a/kernel/time/Makefile b/kernel/time/Makefile
index 9250130646f5..57a413fd0ebf 100644
--- a/kernel/time/Makefile
+++ b/kernel/time/Makefile
@@ -3,7 +3,10 @@ obj-y += timeconv.o posix-clock.o alarmtimer.o
 
 obj-$(CONFIG_GENERIC_CLOCKEVENTS_BUILD)		+= clockevents.o
 obj-$(CONFIG_GENERIC_CLOCKEVENTS)		+= tick-common.o
-obj-$(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST)	+= tick-broadcast.o
+ifeq ($(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST),y)
+ obj-y						+= tick-broadcast.o
+ obj-$(CONFIG_TICK_ONESHOT)			+= tick-broadcast-hrtimer.o
+endif
 obj-$(CONFIG_GENERIC_SCHED_CLOCK)		+= sched_clock.o
 obj-$(CONFIG_TICK_ONESHOT)			+= tick-oneshot.o
 obj-$(CONFIG_TICK_ONESHOT)			+= tick-sched.o
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index 086ad6043bcb..ad362c260ef4 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -439,6 +439,19 @@ void clockevents_config_and_register(struct clock_event_device *dev,
 }
 EXPORT_SYMBOL_GPL(clockevents_config_and_register);
 
+int __clockevents_update_freq(struct clock_event_device *dev, u32 freq)
+{
+	clockevents_config(dev, freq);
+
+	if (dev->mode == CLOCK_EVT_MODE_ONESHOT)
+		return clockevents_program_event(dev, dev->next_event, false);
+
+	if (dev->mode == CLOCK_EVT_MODE_PERIODIC)
+		dev->set_mode(CLOCK_EVT_MODE_PERIODIC, dev);
+
+	return 0;
+}
+
 /**
  * clockevents_update_freq - Update frequency and reprogram a clock event device.
  * @dev:	device to modify
@@ -446,17 +459,22 @@ EXPORT_SYMBOL_GPL(clockevents_config_and_register);
  *
  * Reconfigure and reprogram a clock event device in oneshot
  * mode. Must be called on the cpu for which the device delivers per
- * cpu timer events with interrupts disabled!  Returns 0 on success,
- * -ETIME when the event is in the past.
+ * cpu timer events. If called for the broadcast device the core takes
+ * care of serialization.
+ *
+ * Returns 0 on success, -ETIME when the event is in the past.
  */
 int clockevents_update_freq(struct clock_event_device *dev, u32 freq)
 {
-	clockevents_config(dev, freq);
-
-	if (dev->mode != CLOCK_EVT_MODE_ONESHOT)
-		return 0;
+	unsigned long flags;
+	int ret;
 
-	return clockevents_program_event(dev, dev->next_event, false);
+	local_irq_save(flags);
+	ret = tick_broadcast_update_freq(dev, freq);
+	if (ret == -ENODEV)
+		ret = __clockevents_update_freq(dev, freq);
+	local_irq_restore(flags);
+	return ret;
 }
 
 /*
@@ -524,12 +542,13 @@ void clockevents_resume(void)
 #ifdef CONFIG_GENERIC_CLOCKEVENTS
 /**
  * clockevents_notify - notification about relevant events
+ * Returns 0 on success, any other value on error
  */
-void clockevents_notify(unsigned long reason, void *arg)
+int clockevents_notify(unsigned long reason, void *arg)
 {
 	struct clock_event_device *dev, *tmp;
 	unsigned long flags;
-	int cpu;
+	int cpu, ret = 0;
 
 	raw_spin_lock_irqsave(&clockevents_lock, flags);
 
@@ -542,7 +561,7 @@ void clockevents_notify(unsigned long reason, void *arg)
 
 	case CLOCK_EVT_NOTIFY_BROADCAST_ENTER:
 	case CLOCK_EVT_NOTIFY_BROADCAST_EXIT:
-		tick_broadcast_oneshot_control(reason);
+		ret = tick_broadcast_oneshot_control(reason);
 		break;
 
 	case CLOCK_EVT_NOTIFY_CPU_DYING:
@@ -585,6 +604,7 @@ void clockevents_notify(unsigned long reason, void *arg)
 		break;
 	}
 	raw_spin_unlock_irqrestore(&clockevents_lock, flags);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(clockevents_notify);
 
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index af8d1d4f3d55..419a52cecd20 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -514,12 +514,13 @@ static void sync_cmos_clock(struct work_struct *work)
 		next.tv_sec++;
 		next.tv_nsec -= NSEC_PER_SEC;
 	}
-	schedule_delayed_work(&sync_cmos_work, timespec_to_jiffies(&next));
+	queue_delayed_work(system_power_efficient_wq,
+			   &sync_cmos_work, timespec_to_jiffies(&next));
 }
 
 void ntp_notify_cmos_timer(void)
 {
-	schedule_delayed_work(&sync_cmos_work, 0);
+	queue_delayed_work(system_power_efficient_wq, &sync_cmos_work, 0);
 }
 
 #else
diff --git a/kernel/time/tick-broadcast-hrtimer.c b/kernel/time/tick-broadcast-hrtimer.c
new file mode 100644
index 000000000000..eb682d5c697c
--- /dev/null
+++ b/kernel/time/tick-broadcast-hrtimer.c
@@ -0,0 +1,106 @@
+/*
+ * linux/kernel/time/tick-broadcast-hrtimer.c
+ * This file emulates a local clock event device
+ * via a pseudo clock device.
+ */
+#include <linux/cpu.h>
+#include <linux/err.h>
+#include <linux/hrtimer.h>
+#include <linux/interrupt.h>
+#include <linux/percpu.h>
+#include <linux/profile.h>
+#include <linux/clockchips.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/module.h>
+
+#include "tick-internal.h"
+
+static struct hrtimer bctimer;
+
+static void bc_set_mode(enum clock_event_mode mode,
+			struct clock_event_device *bc)
+{
+	switch (mode) {
+	case CLOCK_EVT_MODE_SHUTDOWN:
+		/*
+		 * Note, we cannot cancel the timer here as we might
+		 * run into the following live lock scenario:
+		 *
+		 * cpu 0		cpu1
+		 * lock(broadcast_lock);
+		 *			hrtimer_interrupt()
+		 *			bc_handler()
+		 *			   tick_handle_oneshot_broadcast();
+		 *			    lock(broadcast_lock);
+		 * hrtimer_cancel()
+		 *  wait_for_callback()
+		 */
+		hrtimer_try_to_cancel(&bctimer);
+		break;
+	default:
+		break;
+	}
+}
+
+/*
+ * This is called from the guts of the broadcast code when the cpu
+ * which is about to enter idle has the earliest broadcast timer event.
+ */
+static int bc_set_next(ktime_t expires, struct clock_event_device *bc)
+{
+	/*
+	 * We try to cancel the timer first. If the callback is on
+	 * flight on some other cpu then we let it handle it. If we
+	 * were able to cancel the timer nothing can rearm it as we
+	 * own broadcast_lock.
+	 *
+	 * However we can also be called from the event handler of
+	 * ce_broadcast_hrtimer itself when it expires. We cannot
+	 * restart the timer because we are in the callback, but we
+	 * can set the expiry time and let the callback return
+	 * HRTIMER_RESTART.
+	 */
+	if (hrtimer_try_to_cancel(&bctimer) >= 0) {
+		hrtimer_start(&bctimer, expires, HRTIMER_MODE_ABS_PINNED);
+		/* Bind the "device" to the cpu */
+		bc->bound_on = smp_processor_id();
+	} else if (bc->bound_on == smp_processor_id()) {
+		hrtimer_set_expires(&bctimer, expires);
+	}
+	return 0;
+}
+
+static struct clock_event_device ce_broadcast_hrtimer = {
+	.set_mode		= bc_set_mode,
+	.set_next_ktime		= bc_set_next,
+	.features		= CLOCK_EVT_FEAT_ONESHOT |
+				  CLOCK_EVT_FEAT_KTIME |
+				  CLOCK_EVT_FEAT_HRTIMER,
+	.rating			= 0,
+	.bound_on		= -1,
+	.min_delta_ns		= 1,
+	.max_delta_ns		= KTIME_MAX,
+	.min_delta_ticks	= 1,
+	.max_delta_ticks	= ULONG_MAX,
+	.mult			= 1,
+	.shift			= 0,
+	.cpumask		= cpu_all_mask,
+};
+
+static enum hrtimer_restart bc_handler(struct hrtimer *t)
+{
+	ce_broadcast_hrtimer.event_handler(&ce_broadcast_hrtimer);
+
+	if (ce_broadcast_hrtimer.next_event.tv64 == KTIME_MAX)
+		return HRTIMER_NORESTART;
+
+	return HRTIMER_RESTART;
+}
+
+void tick_setup_hrtimer_broadcast(void)
+{
+	hrtimer_init(&bctimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
+	bctimer.function = bc_handler;
+	clockevents_register_device(&ce_broadcast_hrtimer);
+}
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 98977a57ac72..64c5990fd500 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -120,6 +120,19 @@ int tick_is_broadcast_device(struct clock_event_device *dev)
 	return (dev && tick_broadcast_device.evtdev == dev);
 }
 
+int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq)
+{
+	int ret = -ENODEV;
+
+	if (tick_is_broadcast_device(dev)) {
+		raw_spin_lock(&tick_broadcast_lock);
+		ret = __clockevents_update_freq(dev, freq);
+		raw_spin_unlock(&tick_broadcast_lock);
+	}
+	return ret;
+}
+
+
 static void err_broadcast(const struct cpumask *mask)
 {
 	pr_crit_once("Failed to broadcast timer tick. Some CPUs may be unresponsive.\n");
@@ -272,12 +285,8 @@ static void tick_do_broadcast(struct cpumask *mask)
  */
 static void tick_do_periodic_broadcast(void)
 {
-	raw_spin_lock(&tick_broadcast_lock);
-
 	cpumask_and(tmpmask, cpu_online_mask, tick_broadcast_mask);
 	tick_do_broadcast(tmpmask);
-
-	raw_spin_unlock(&tick_broadcast_lock);
 }
 
 /*
@@ -287,13 +296,15 @@ static void tick_handle_periodic_broadcast(struct clock_event_device *dev)
 {
 	ktime_t next;
 
+	raw_spin_lock(&tick_broadcast_lock);
+
 	tick_do_periodic_broadcast();
 
 	/*
 	 * The device is in periodic mode. No reprogramming necessary:
 	 */
 	if (dev->mode == CLOCK_EVT_MODE_PERIODIC)
-		return;
+		goto unlock;
 
 	/*
 	 * Setup the next period for devices, which do not have
@@ -306,9 +317,11 @@ static void tick_handle_periodic_broadcast(struct clock_event_device *dev)
 		next = ktime_add(next, tick_period);
 
 		if (!clockevents_program_event(dev, next, false))
-			return;
+			goto unlock;
 		tick_do_periodic_broadcast();
 	}
+unlock:
+	raw_spin_unlock(&tick_broadcast_lock);
 }
 
 /*
@@ -630,24 +643,61 @@ again:
 	raw_spin_unlock(&tick_broadcast_lock);
 }
 
+static int broadcast_needs_cpu(struct clock_event_device *bc, int cpu)
+{
+	if (!(bc->features & CLOCK_EVT_FEAT_HRTIMER))
+		return 0;
+	if (bc->next_event.tv64 == KTIME_MAX)
+		return 0;
+	return bc->bound_on == cpu ? -EBUSY : 0;
+}
+
+static void broadcast_shutdown_local(struct clock_event_device *bc,
+				     struct clock_event_device *dev)
+{
+	/*
+	 * For hrtimer based broadcasting we cannot shutdown the cpu
+	 * local device if our own event is the first one to expire or
+	 * if we own the broadcast timer.
+	 */
+	if (bc->features & CLOCK_EVT_FEAT_HRTIMER) {
+		if (broadcast_needs_cpu(bc, smp_processor_id()))
+			return;
+		if (dev->next_event.tv64 < bc->next_event.tv64)
+			return;
+	}
+	clockevents_set_mode(dev, CLOCK_EVT_MODE_SHUTDOWN);
+}
+
+static void broadcast_move_bc(int deadcpu)
+{
+	struct clock_event_device *bc = tick_broadcast_device.evtdev;
+
+	if (!bc || !broadcast_needs_cpu(bc, deadcpu))
+		return;
+	/* This moves the broadcast assignment to this cpu */
+	clockevents_program_event(bc, bc->next_event, 1);
+}
+
 /*
  * Powerstate information: The system enters/leaves a state, where
  * affected devices might stop
+ * Returns 0 on success, -EBUSY if the cpu is used to broadcast wakeups.
  */
-void tick_broadcast_oneshot_control(unsigned long reason)
+int tick_broadcast_oneshot_control(unsigned long reason)
 {
 	struct clock_event_device *bc, *dev;
 	struct tick_device *td;
 	unsigned long flags;
 	ktime_t now;
-	int cpu;
+	int cpu, ret = 0;
 
 	/*
 	 * Periodic mode does not care about the enter/exit of power
 	 * states
 	 */
 	if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC)
-		return;
+		return 0;
 
 	/*
 	 * We are called with preemtion disabled from the depth of the
@@ -658,7 +708,7 @@ void tick_broadcast_oneshot_control(unsigned long reason)
 	dev = td->evtdev;
 
 	if (!(dev->features & CLOCK_EVT_FEAT_C3STOP))
-		return;
+		return 0;
 
 	bc = tick_broadcast_device.evtdev;
 
@@ -666,7 +716,7 @@ void tick_broadcast_oneshot_control(unsigned long reason)
 	if (reason == CLOCK_EVT_NOTIFY_BROADCAST_ENTER) {
 		if (!cpumask_test_and_set_cpu(cpu, tick_broadcast_oneshot_mask)) {
 			WARN_ON_ONCE(cpumask_test_cpu(cpu, tick_broadcast_pending_mask));
-			clockevents_set_mode(dev, CLOCK_EVT_MODE_SHUTDOWN);
+			broadcast_shutdown_local(bc, dev);
 			/*
 			 * We only reprogram the broadcast timer if we
 			 * did not mark ourself in the force mask and
@@ -679,6 +729,16 @@ void tick_broadcast_oneshot_control(unsigned long reason)
 			    dev->next_event.tv64 < bc->next_event.tv64)
 				tick_broadcast_set_event(bc, cpu, dev->next_event, 1);
 		}
+		/*
+		 * If the current CPU owns the hrtimer broadcast
+		 * mechanism, it cannot go deep idle and we remove the
+		 * CPU from the broadcast mask. We don't have to go
+		 * through the EXIT path as the local timer is not
+		 * shutdown.
+		 */
+		ret = broadcast_needs_cpu(bc, cpu);
+		if (ret)
+			cpumask_clear_cpu(cpu, tick_broadcast_oneshot_mask);
 	} else {
 		if (cpumask_test_and_clear_cpu(cpu, tick_broadcast_oneshot_mask)) {
 			clockevents_set_mode(dev, CLOCK_EVT_MODE_ONESHOT);
@@ -746,6 +806,7 @@ void tick_broadcast_oneshot_control(unsigned long reason)
 	}
 out:
 	raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
+	return ret;
 }
 
 /*
@@ -852,6 +913,8 @@ void tick_shutdown_broadcast_oneshot(unsigned int *cpup)
 	cpumask_clear_cpu(cpu, tick_broadcast_pending_mask);
 	cpumask_clear_cpu(cpu, tick_broadcast_force_mask);
 
+	broadcast_move_bc(cpu);
+
 	raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
 }
 
diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c
index 20b2fe37d105..0a0608edeb26 100644
--- a/kernel/time/tick-common.c
+++ b/kernel/time/tick-common.c
@@ -98,18 +98,19 @@ static void tick_periodic(int cpu)
 void tick_handle_periodic(struct clock_event_device *dev)
 {
 	int cpu = smp_processor_id();
-	ktime_t next;
+	ktime_t next = dev->next_event;
 
 	tick_periodic(cpu);
 
 	if (dev->mode != CLOCK_EVT_MODE_ONESHOT)
 		return;
-	/*
-	 * Setup the next period for devices, which do not have
-	 * periodic mode:
-	 */
-	next = ktime_add(dev->next_event, tick_period);
 	for (;;) {
+		/*
+		 * Setup the next period for devices, which do not have
+		 * periodic mode:
+		 */
+		next = ktime_add(next, tick_period);
+
 		if (!clockevents_program_event(dev, next, false))
 			return;
 		/*
@@ -118,12 +119,11 @@ void tick_handle_periodic(struct clock_event_device *dev)
 		 * to be sure we're using a real hardware clocksource.
 		 * Otherwise we could get trapped in an infinite
 		 * loop, as the tick_periodic() increments jiffies,
-		 * when then will increment time, posibly causing
+		 * which then will increment time, possibly causing
 		 * the loop to trigger again and again.
 		 */
 		if (timekeeping_valid_for_hres())
 			tick_periodic(cpu);
-		next = ktime_add(next, tick_period);
 	}
 }
 
@@ -276,7 +276,7 @@ static bool tick_check_preferred(struct clock_event_device *curdev,
 bool tick_check_replacement(struct clock_event_device *curdev,
 			    struct clock_event_device *newdev)
 {
-	if (tick_check_percpu(curdev, newdev, smp_processor_id()))
+	if (!tick_check_percpu(curdev, newdev, smp_processor_id()))
 		return false;
 
 	return tick_check_preferred(curdev, newdev);
diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h
index 8329669b51ec..7ab92b19965a 100644
--- a/kernel/time/tick-internal.h
+++ b/kernel/time/tick-internal.h
@@ -46,7 +46,7 @@ extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *));
 extern void tick_resume_oneshot(void);
 # ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
 extern void tick_broadcast_setup_oneshot(struct clock_event_device *bc);
-extern void tick_broadcast_oneshot_control(unsigned long reason);
+extern int tick_broadcast_oneshot_control(unsigned long reason);
 extern void tick_broadcast_switch_to_oneshot(void);
 extern void tick_shutdown_broadcast_oneshot(unsigned int *cpup);
 extern int tick_resume_broadcast_oneshot(struct clock_event_device *bc);
@@ -58,7 +58,7 @@ static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
 {
 	BUG();
 }
-static inline void tick_broadcast_oneshot_control(unsigned long reason) { }
+static inline int tick_broadcast_oneshot_control(unsigned long reason) { return 0; }
 static inline void tick_broadcast_switch_to_oneshot(void) { }
 static inline void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { }
 static inline int tick_broadcast_oneshot_active(void) { return 0; }
@@ -87,7 +87,7 @@ static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
 {
 	BUG();
 }
-static inline void tick_broadcast_oneshot_control(unsigned long reason) { }
+static inline int tick_broadcast_oneshot_control(unsigned long reason) { return 0; }
 static inline void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { }
 static inline int tick_resume_broadcast_oneshot(struct clock_event_device *bc)
 {
@@ -111,6 +111,7 @@ extern int tick_resume_broadcast(void);
 extern void tick_broadcast_init(void);
 extern void
 tick_set_periodic_handler(struct clock_event_device *dev, int broadcast);
+int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq);
 
 #else /* !BROADCAST */
 
@@ -133,6 +134,8 @@ static inline void tick_shutdown_broadcast(unsigned int *cpup) { }
 static inline void tick_suspend_broadcast(void) { }
 static inline int tick_resume_broadcast(void) { return 0; }
 static inline void tick_broadcast_init(void) { }
+static inline int tick_broadcast_update_freq(struct clock_event_device *dev,
+					     u32 freq) { return -ENODEV; }
 
 /*
  * Set the periodic handler in non broadcast mode
@@ -152,6 +155,8 @@ static inline int tick_device_is_functional(struct clock_event_device *dev)
 	return !(dev->features & CLOCK_EVT_FEAT_DUMMY);
 }
 
+int __clockevents_update_freq(struct clock_event_device *dev, u32 freq);
+
 #endif
 
 extern void do_timer(unsigned long ticks);
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 9f8af69c67ec..6558b7ac112d 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -84,6 +84,9 @@ static void tick_do_update_jiffies64(ktime_t now)
 
 		/* Keep the tick_next_period variable up to date */
 		tick_next_period = ktime_add(last_jiffies_update, tick_period);
+	} else {
+		write_sequnlock(&jiffies_lock);
+		return;
 	}
 	write_sequnlock(&jiffies_lock);
 	update_wall_time();
@@ -967,7 +970,7 @@ static void tick_nohz_switch_to_nohz(void)
 	struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched);
 	ktime_t next;
 
-	if (!tick_nohz_active)
+	if (!tick_nohz_enabled)
 		return;
 
 	local_irq_disable();
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 5b40279ecd71..f7df8ea21707 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -22,6 +22,7 @@
 #include <linux/tick.h>
 #include <linux/stop_machine.h>
 #include <linux/pvclock_gtod.h>
+#include <linux/compiler.h>
 
 #include "tick-internal.h"
 #include "ntp_internal.h"
@@ -760,7 +761,7 @@ u64 timekeeping_max_deferment(void)
  *
  *  XXX - Do be sure to remove it once all arches implement it.
  */
-void __attribute__((weak)) read_persistent_clock(struct timespec *ts)
+void __weak read_persistent_clock(struct timespec *ts)
 {
 	ts->tv_sec = 0;
 	ts->tv_nsec = 0;
@@ -775,7 +776,7 @@ void __attribute__((weak)) read_persistent_clock(struct timespec *ts)
  *
  *  XXX - Do be sure to remove it once all arches implement it.
  */
-void __attribute__((weak)) read_boot_clock(struct timespec *ts)
+void __weak read_boot_clock(struct timespec *ts)
 {
 	ts->tv_sec = 0;
 	ts->tv_nsec = 0;
diff --git a/kernel/time/timekeeping_debug.c b/kernel/time/timekeeping_debug.c
index 802433a4f5eb..4d54f97558df 100644
--- a/kernel/time/timekeeping_debug.c
+++ b/kernel/time/timekeeping_debug.c
@@ -21,6 +21,8 @@
 #include <linux/seq_file.h>
 #include <linux/time.h>
 
+#include "timekeeping_internal.h"
+
 static unsigned int sleep_time_bin[32] = {0};
 
 static int tk_debug_show_sleep_time(struct seq_file *s, void *data)
diff --git a/kernel/timer.c b/kernel/timer.c
index accfd241b9e5..3bb01a323b2a 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -52,7 +52,7 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/timer.h>
 
-u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES;
+__visible u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES;
 
 EXPORT_SYMBOL(jiffies_64);
 
@@ -81,6 +81,7 @@ struct tvec_base {
 	unsigned long timer_jiffies;
 	unsigned long next_timer;
 	unsigned long active_timers;
+	unsigned long all_timers;
 	struct tvec_root tv1;
 	struct tvec tv2;
 	struct tvec tv3;
@@ -337,6 +338,20 @@ void set_timer_slack(struct timer_list *timer, int slack_hz)
 }
 EXPORT_SYMBOL_GPL(set_timer_slack);
 
+/*
+ * If the list is empty, catch up ->timer_jiffies to the current time.
+ * The caller must hold the tvec_base lock.  Returns true if the list
+ * was empty and therefore ->timer_jiffies was updated.
+ */
+static bool catchup_timer_jiffies(struct tvec_base *base)
+{
+	if (!base->all_timers) {
+		base->timer_jiffies = jiffies;
+		return true;
+	}
+	return false;
+}
+
 static void
 __internal_add_timer(struct tvec_base *base, struct timer_list *timer)
 {
@@ -383,15 +398,17 @@ __internal_add_timer(struct tvec_base *base, struct timer_list *timer)
 
 static void internal_add_timer(struct tvec_base *base, struct timer_list *timer)
 {
+	(void)catchup_timer_jiffies(base);
 	__internal_add_timer(base, timer);
 	/*
 	 * Update base->active_timers and base->next_timer
 	 */
 	if (!tbase_get_deferrable(timer->base)) {
-		if (time_before(timer->expires, base->next_timer))
+		if (!base->active_timers++ ||
+		    time_before(timer->expires, base->next_timer))
 			base->next_timer = timer->expires;
-		base->active_timers++;
 	}
+	base->all_timers++;
 }
 
 #ifdef CONFIG_TIMER_STATS
@@ -671,6 +688,8 @@ detach_expired_timer(struct timer_list *timer, struct tvec_base *base)
 	detach_timer(timer, true);
 	if (!tbase_get_deferrable(timer->base))
 		base->active_timers--;
+	base->all_timers--;
+	(void)catchup_timer_jiffies(base);
 }
 
 static int detach_if_pending(struct timer_list *timer, struct tvec_base *base,
@@ -685,6 +704,8 @@ static int detach_if_pending(struct timer_list *timer, struct tvec_base *base,
 		if (timer->expires == base->next_timer)
 			base->next_timer = base->timer_jiffies;
 	}
+	base->all_timers--;
+	(void)catchup_timer_jiffies(base);
 	return 1;
 }
 
@@ -739,12 +760,7 @@ __mod_timer(struct timer_list *timer, unsigned long expires,
 
 	debug_activate(timer, expires);
 
-	cpu = smp_processor_id();
-
-#if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
-	if (!pinned && get_sysctl_timer_migration() && idle_cpu(cpu))
-		cpu = get_nohz_timer_target();
-#endif
+	cpu = get_nohz_timer_target(pinned);
 	new_base = per_cpu(tvec_bases, cpu);
 
 	if (base != new_base) {
@@ -822,7 +838,7 @@ unsigned long apply_slack(struct timer_list *timer, unsigned long expires)
 
 	bit = find_last_bit(&mask, BITS_PER_LONG);
 
-	mask = (1 << bit) - 1;
+	mask = (1UL << bit) - 1;
 
 	expires_limit = expires_limit & ~(mask);
 
@@ -939,8 +955,15 @@ void add_timer_on(struct timer_list *timer, int cpu)
 	 * with the timer by holding the timer base lock. This also
 	 * makes sure that a CPU on the way to stop its tick can not
 	 * evaluate the timer wheel.
+	 *
+	 * Spare the IPI for deferrable timers on idle targets though.
+	 * The next busy ticks will take care of it. Except full dynticks
+	 * require special care against races with idle_cpu(), lets deal
+	 * with that later.
 	 */
-	wake_up_nohz_cpu(cpu);
+	if (!tbase_get_deferrable(timer->base) || tick_nohz_full_cpu(cpu))
+		wake_up_nohz_cpu(cpu);
+
 	spin_unlock_irqrestore(&base->lock, flags);
 }
 EXPORT_SYMBOL_GPL(add_timer_on);
@@ -1146,6 +1169,10 @@ static inline void __run_timers(struct tvec_base *base)
 	struct timer_list *timer;
 
 	spin_lock_irq(&base->lock);
+	if (catchup_timer_jiffies(base)) {
+		spin_unlock_irq(&base->lock);
+		return;
+	}
 	while (time_after_eq(jiffies, base->timer_jiffies)) {
 		struct list_head work_list;
 		struct list_head *head = &work_list;
@@ -1160,7 +1187,7 @@ static inline void __run_timers(struct tvec_base *base)
 					!cascade(base, &base->tv4, INDEX(2)))
 			cascade(base, &base->tv5, INDEX(3));
 		++base->timer_jiffies;
-		list_replace_init(base->tv1.vec + index, &work_list);
+		list_replace_init(base->tv1.vec + index, head);
 		while (!list_empty(head)) {
 			void (*fn)(unsigned long);
 			unsigned long data;
@@ -1523,9 +1550,8 @@ static int init_timers_cpu(int cpu)
 			if (!base)
 				return -ENOMEM;
 
-			/* Make sure that tvec_base is 2 byte aligned */
-			if (tbase_get_deferrable(base)) {
-				WARN_ON(1);
+			/* Make sure tvec_base has TIMER_FLAG_MASK bits free */
+			if (WARN_ON(base != tbase_get_base(base))) {
 				kfree(base);
 				return -ENOMEM;
 			}
@@ -1559,6 +1585,7 @@ static int init_timers_cpu(int cpu)
 	base->timer_jiffies = jiffies;
 	base->next_timer = base->timer_jiffies;
 	base->active_timers = 0;
+	base->all_timers = 0;
 	return 0;
 }
 
@@ -1648,9 +1675,9 @@ void __init init_timers(void)
 
 	err = timer_cpu_notify(&timers_nb, (unsigned long)CPU_UP_PREPARE,
 			       (void *)(long)smp_processor_id());
-	init_timer_stats();
-
 	BUG_ON(err != NOTIFY_OK);
+
+	init_timer_stats();
 	register_cpu_notifier(&timers_nb);
 	open_softirq(TIMER_SOFTIRQ, run_timer_softirq);
 }
diff --git a/kernel/torture.c b/kernel/torture.c
new file mode 100644
index 000000000000..acc9afc2f26e
--- /dev/null
+++ b/kernel/torture.c
@@ -0,0 +1,719 @@
+/*
+ * Common functions for in-kernel torture tests.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
+ *
+ * Copyright (C) IBM Corporation, 2014
+ *
+ * Author: Paul E. McKenney <paulmck@us.ibm.com>
+ *	Based on kernel/rcu/torture.c.
+ */
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kthread.h>
+#include <linux/err.h>
+#include <linux/spinlock.h>
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/atomic.h>
+#include <linux/bitops.h>
+#include <linux/completion.h>
+#include <linux/moduleparam.h>
+#include <linux/percpu.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/freezer.h>
+#include <linux/cpu.h>
+#include <linux/delay.h>
+#include <linux/stat.h>
+#include <linux/slab.h>
+#include <linux/trace_clock.h>
+#include <asm/byteorder.h>
+#include <linux/torture.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com>");
+
+static char *torture_type;
+static bool verbose;
+
+/* Mediate rmmod and system shutdown.  Concurrent rmmod & shutdown illegal! */
+#define FULLSTOP_DONTSTOP 0	/* Normal operation. */
+#define FULLSTOP_SHUTDOWN 1	/* System shutdown with torture running. */
+#define FULLSTOP_RMMOD    2	/* Normal rmmod of torture. */
+static int fullstop = FULLSTOP_RMMOD;
+static DEFINE_MUTEX(fullstop_mutex);
+static int *torture_runnable;
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+/*
+ * Variables for online-offline handling.  Only present if CPU hotplug
+ * is enabled, otherwise does nothing.
+ */
+
+static struct task_struct *onoff_task;
+static long onoff_holdoff;
+static long onoff_interval;
+static long n_offline_attempts;
+static long n_offline_successes;
+static unsigned long sum_offline;
+static int min_offline = -1;
+static int max_offline;
+static long n_online_attempts;
+static long n_online_successes;
+static unsigned long sum_online;
+static int min_online = -1;
+static int max_online;
+
+/*
+ * Execute random CPU-hotplug operations at the interval specified
+ * by the onoff_interval.
+ */
+static int
+torture_onoff(void *arg)
+{
+	int cpu;
+	unsigned long delta;
+	int maxcpu = -1;
+	DEFINE_TORTURE_RANDOM(rand);
+	int ret;
+	unsigned long starttime;
+
+	VERBOSE_TOROUT_STRING("torture_onoff task started");
+	for_each_online_cpu(cpu)
+		maxcpu = cpu;
+	WARN_ON(maxcpu < 0);
+	if (onoff_holdoff > 0) {
+		VERBOSE_TOROUT_STRING("torture_onoff begin holdoff");
+		schedule_timeout_interruptible(onoff_holdoff);
+		VERBOSE_TOROUT_STRING("torture_onoff end holdoff");
+	}
+	while (!torture_must_stop()) {
+		cpu = (torture_random(&rand) >> 4) % (maxcpu + 1);
+		if (cpu_online(cpu) && cpu_is_hotpluggable(cpu)) {
+			if (verbose)
+				pr_alert("%s" TORTURE_FLAG
+					 "torture_onoff task: offlining %d\n",
+					 torture_type, cpu);
+			starttime = jiffies;
+			n_offline_attempts++;
+			ret = cpu_down(cpu);
+			if (ret) {
+				if (verbose)
+					pr_alert("%s" TORTURE_FLAG
+						 "torture_onoff task: offline %d failed: errno %d\n",
+						 torture_type, cpu, ret);
+			} else {
+				if (verbose)
+					pr_alert("%s" TORTURE_FLAG
+						 "torture_onoff task: offlined %d\n",
+						 torture_type, cpu);
+				n_offline_successes++;
+				delta = jiffies - starttime;
+				sum_offline += delta;
+				if (min_offline < 0) {
+					min_offline = delta;
+					max_offline = delta;
+				}
+				if (min_offline > delta)
+					min_offline = delta;
+				if (max_offline < delta)
+					max_offline = delta;
+			}
+		} else if (cpu_is_hotpluggable(cpu)) {
+			if (verbose)
+				pr_alert("%s" TORTURE_FLAG
+					 "torture_onoff task: onlining %d\n",
+					 torture_type, cpu);
+			starttime = jiffies;
+			n_online_attempts++;
+			ret = cpu_up(cpu);
+			if (ret) {
+				if (verbose)
+					pr_alert("%s" TORTURE_FLAG
+						 "torture_onoff task: online %d failed: errno %d\n",
+						 torture_type, cpu, ret);
+			} else {
+				if (verbose)
+					pr_alert("%s" TORTURE_FLAG
+						 "torture_onoff task: onlined %d\n",
+						 torture_type, cpu);
+				n_online_successes++;
+				delta = jiffies - starttime;
+				sum_online += delta;
+				if (min_online < 0) {
+					min_online = delta;
+					max_online = delta;
+				}
+				if (min_online > delta)
+					min_online = delta;
+				if (max_online < delta)
+					max_online = delta;
+			}
+		}
+		schedule_timeout_interruptible(onoff_interval);
+	}
+	torture_kthread_stopping("torture_onoff");
+	return 0;
+}
+
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+
+/*
+ * Initiate online-offline handling.
+ */
+int torture_onoff_init(long ooholdoff, long oointerval)
+{
+	int ret = 0;
+
+#ifdef CONFIG_HOTPLUG_CPU
+	onoff_holdoff = ooholdoff;
+	onoff_interval = oointerval;
+	if (onoff_interval <= 0)
+		return 0;
+	ret = torture_create_kthread(torture_onoff, NULL, onoff_task);
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+	return ret;
+}
+EXPORT_SYMBOL_GPL(torture_onoff_init);
+
+/*
+ * Clean up after online/offline testing.
+ */
+static void torture_onoff_cleanup(void)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+	if (onoff_task == NULL)
+		return;
+	VERBOSE_TOROUT_STRING("Stopping torture_onoff task");
+	kthread_stop(onoff_task);
+	onoff_task = NULL;
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+}
+EXPORT_SYMBOL_GPL(torture_onoff_cleanup);
+
+/*
+ * Print online/offline testing statistics.
+ */
+char *torture_onoff_stats(char *page)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+	page += sprintf(page,
+		       "onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ",
+		       n_online_successes, n_online_attempts,
+		       n_offline_successes, n_offline_attempts,
+		       min_online, max_online,
+		       min_offline, max_offline,
+		       sum_online, sum_offline, HZ);
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+	return page;
+}
+EXPORT_SYMBOL_GPL(torture_onoff_stats);
+
+/*
+ * Were all the online/offline operations successful?
+ */
+bool torture_onoff_failures(void)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+	return n_online_successes != n_online_attempts ||
+	       n_offline_successes != n_offline_attempts;
+#else /* #ifdef CONFIG_HOTPLUG_CPU */
+	return false;
+#endif /* #else #ifdef CONFIG_HOTPLUG_CPU */
+}
+EXPORT_SYMBOL_GPL(torture_onoff_failures);
+
+#define TORTURE_RANDOM_MULT	39916801  /* prime */
+#define TORTURE_RANDOM_ADD	479001701 /* prime */
+#define TORTURE_RANDOM_REFRESH	10000
+
+/*
+ * Crude but fast random-number generator.  Uses a linear congruential
+ * generator, with occasional help from cpu_clock().
+ */
+unsigned long
+torture_random(struct torture_random_state *trsp)
+{
+	if (--trsp->trs_count < 0) {
+		trsp->trs_state += (unsigned long)local_clock();
+		trsp->trs_count = TORTURE_RANDOM_REFRESH;
+	}
+	trsp->trs_state = trsp->trs_state * TORTURE_RANDOM_MULT +
+		TORTURE_RANDOM_ADD;
+	return swahw32(trsp->trs_state);
+}
+EXPORT_SYMBOL_GPL(torture_random);
+
+/*
+ * Variables for shuffling.  The idea is to ensure that each CPU stays
+ * idle for an extended period to test interactions with dyntick idle,
+ * as well as interactions with any per-CPU varibles.
+ */
+struct shuffle_task {
+	struct list_head st_l;
+	struct task_struct *st_t;
+};
+
+static long shuffle_interval;	/* In jiffies. */
+static struct task_struct *shuffler_task;
+static cpumask_var_t shuffle_tmp_mask;
+static int shuffle_idle_cpu;	/* Force all torture tasks off this CPU */
+static struct list_head shuffle_task_list = LIST_HEAD_INIT(shuffle_task_list);
+static DEFINE_MUTEX(shuffle_task_mutex);
+
+/*
+ * Register a task to be shuffled.  If there is no memory, just splat
+ * and don't bother registering.
+ */
+void torture_shuffle_task_register(struct task_struct *tp)
+{
+	struct shuffle_task *stp;
+
+	if (WARN_ON_ONCE(tp == NULL))
+		return;
+	stp = kmalloc(sizeof(*stp), GFP_KERNEL);
+	if (WARN_ON_ONCE(stp == NULL))
+		return;
+	stp->st_t = tp;
+	mutex_lock(&shuffle_task_mutex);
+	list_add(&stp->st_l, &shuffle_task_list);
+	mutex_unlock(&shuffle_task_mutex);
+}
+EXPORT_SYMBOL_GPL(torture_shuffle_task_register);
+
+/*
+ * Unregister all tasks, for example, at the end of the torture run.
+ */
+static void torture_shuffle_task_unregister_all(void)
+{
+	struct shuffle_task *stp;
+	struct shuffle_task *p;
+
+	mutex_lock(&shuffle_task_mutex);
+	list_for_each_entry_safe(stp, p, &shuffle_task_list, st_l) {
+		list_del(&stp->st_l);
+		kfree(stp);
+	}
+	mutex_unlock(&shuffle_task_mutex);
+}
+
+/* Shuffle tasks such that we allow shuffle_idle_cpu to become idle.
+ * A special case is when shuffle_idle_cpu = -1, in which case we allow
+ * the tasks to run on all CPUs.
+ */
+static void torture_shuffle_tasks(void)
+{
+	struct shuffle_task *stp;
+
+	cpumask_setall(shuffle_tmp_mask);
+	get_online_cpus();
+
+	/* No point in shuffling if there is only one online CPU (ex: UP) */
+	if (num_online_cpus() == 1) {
+		put_online_cpus();
+		return;
+	}
+
+	/* Advance to the next CPU.  Upon overflow, don't idle any CPUs. */
+	shuffle_idle_cpu = cpumask_next(shuffle_idle_cpu, shuffle_tmp_mask);
+	if (shuffle_idle_cpu >= nr_cpu_ids)
+		shuffle_idle_cpu = -1;
+	if (shuffle_idle_cpu != -1) {
+		cpumask_clear_cpu(shuffle_idle_cpu, shuffle_tmp_mask);
+		if (cpumask_empty(shuffle_tmp_mask)) {
+			put_online_cpus();
+			return;
+		}
+	}
+
+	mutex_lock(&shuffle_task_mutex);
+	list_for_each_entry(stp, &shuffle_task_list, st_l)
+		set_cpus_allowed_ptr(stp->st_t, shuffle_tmp_mask);
+	mutex_unlock(&shuffle_task_mutex);
+
+	put_online_cpus();
+}
+
+/* Shuffle tasks across CPUs, with the intent of allowing each CPU in the
+ * system to become idle at a time and cut off its timer ticks. This is meant
+ * to test the support for such tickless idle CPU in RCU.
+ */
+static int torture_shuffle(void *arg)
+{
+	VERBOSE_TOROUT_STRING("torture_shuffle task started");
+	do {
+		schedule_timeout_interruptible(shuffle_interval);
+		torture_shuffle_tasks();
+		torture_shutdown_absorb("torture_shuffle");
+	} while (!torture_must_stop());
+	torture_kthread_stopping("torture_shuffle");
+	return 0;
+}
+
+/*
+ * Start the shuffler, with shuffint in jiffies.
+ */
+int torture_shuffle_init(long shuffint)
+{
+	shuffle_interval = shuffint;
+
+	shuffle_idle_cpu = -1;
+
+	if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) {
+		VERBOSE_TOROUT_ERRSTRING("Failed to alloc mask");
+		return -ENOMEM;
+	}
+
+	/* Create the shuffler thread */
+	return torture_create_kthread(torture_shuffle, NULL, shuffler_task);
+}
+EXPORT_SYMBOL_GPL(torture_shuffle_init);
+
+/*
+ * Stop the shuffling.
+ */
+static void torture_shuffle_cleanup(void)
+{
+	torture_shuffle_task_unregister_all();
+	if (shuffler_task) {
+		VERBOSE_TOROUT_STRING("Stopping torture_shuffle task");
+		kthread_stop(shuffler_task);
+		free_cpumask_var(shuffle_tmp_mask);
+	}
+	shuffler_task = NULL;
+}
+EXPORT_SYMBOL_GPL(torture_shuffle_cleanup);
+
+/*
+ * Variables for auto-shutdown.  This allows "lights out" torture runs
+ * to be fully scripted.
+ */
+static int shutdown_secs;		/* desired test duration in seconds. */
+static struct task_struct *shutdown_task;
+static unsigned long shutdown_time;	/* jiffies to system shutdown. */
+static void (*torture_shutdown_hook)(void);
+
+/*
+ * Absorb kthreads into a kernel function that won't return, so that
+ * they won't ever access module text or data again.
+ */
+void torture_shutdown_absorb(const char *title)
+{
+	while (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
+		pr_notice("torture thread %s parking due to system shutdown\n",
+			  title);
+		schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT);
+	}
+}
+EXPORT_SYMBOL_GPL(torture_shutdown_absorb);
+
+/*
+ * Cause the torture test to shutdown the system after the test has
+ * run for the time specified by the shutdown_secs parameter.
+ */
+static int torture_shutdown(void *arg)
+{
+	long delta;
+	unsigned long jiffies_snap;
+
+	VERBOSE_TOROUT_STRING("torture_shutdown task started");
+	jiffies_snap = jiffies;
+	while (ULONG_CMP_LT(jiffies_snap, shutdown_time) &&
+	       !torture_must_stop()) {
+		delta = shutdown_time - jiffies_snap;
+		if (verbose)
+			pr_alert("%s" TORTURE_FLAG
+				 "torture_shutdown task: %lu jiffies remaining\n",
+				 torture_type, delta);
+		schedule_timeout_interruptible(delta);
+		jiffies_snap = jiffies;
+	}
+	if (torture_must_stop()) {
+		torture_kthread_stopping("torture_shutdown");
+		return 0;
+	}
+
+	/* OK, shut down the system. */
+
+	VERBOSE_TOROUT_STRING("torture_shutdown task shutting down system");
+	shutdown_task = NULL;	/* Avoid self-kill deadlock. */
+	if (torture_shutdown_hook)
+		torture_shutdown_hook();
+	else
+		VERBOSE_TOROUT_STRING("No torture_shutdown_hook(), skipping.");
+	kernel_power_off();	/* Shut down the system. */
+	return 0;
+}
+
+/*
+ * Start up the shutdown task.
+ */
+int torture_shutdown_init(int ssecs, void (*cleanup)(void))
+{
+	int ret = 0;
+
+	shutdown_secs = ssecs;
+	torture_shutdown_hook = cleanup;
+	if (shutdown_secs > 0) {
+		shutdown_time = jiffies + shutdown_secs * HZ;
+		ret = torture_create_kthread(torture_shutdown, NULL,
+					     shutdown_task);
+	}
+	return ret;
+}
+EXPORT_SYMBOL_GPL(torture_shutdown_init);
+
+/*
+ * Detect and respond to a system shutdown.
+ */
+static int torture_shutdown_notify(struct notifier_block *unused1,
+				   unsigned long unused2, void *unused3)
+{
+	mutex_lock(&fullstop_mutex);
+	if (ACCESS_ONCE(fullstop) == FULLSTOP_DONTSTOP) {
+		VERBOSE_TOROUT_STRING("Unscheduled system shutdown detected");
+		ACCESS_ONCE(fullstop) = FULLSTOP_SHUTDOWN;
+	} else {
+		pr_warn("Concurrent rmmod and shutdown illegal!\n");
+	}
+	mutex_unlock(&fullstop_mutex);
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block torture_shutdown_nb = {
+	.notifier_call = torture_shutdown_notify,
+};
+
+/*
+ * Shut down the shutdown task.  Say what???  Heh!  This can happen if
+ * the torture module gets an rmmod before the shutdown time arrives.  ;-)
+ */
+static void torture_shutdown_cleanup(void)
+{
+	unregister_reboot_notifier(&torture_shutdown_nb);
+	if (shutdown_task != NULL) {
+		VERBOSE_TOROUT_STRING("Stopping torture_shutdown task");
+		kthread_stop(shutdown_task);
+	}
+	shutdown_task = NULL;
+}
+
+/*
+ * Variables for stuttering, which means to periodically pause and
+ * restart testing in order to catch bugs that appear when load is
+ * suddenly applied to or removed from the system.
+ */
+static struct task_struct *stutter_task;
+static int stutter_pause_test;
+static int stutter;
+
+/*
+ * Block until the stutter interval ends.  This must be called periodically
+ * by all running kthreads that need to be subject to stuttering.
+ */
+void stutter_wait(const char *title)
+{
+	while (ACCESS_ONCE(stutter_pause_test) ||
+	       (torture_runnable && !ACCESS_ONCE(*torture_runnable))) {
+		if (stutter_pause_test)
+			schedule_timeout_interruptible(1);
+		else
+			schedule_timeout_interruptible(round_jiffies_relative(HZ));
+		torture_shutdown_absorb(title);
+	}
+}
+EXPORT_SYMBOL_GPL(stutter_wait);
+
+/*
+ * Cause the torture test to "stutter", starting and stopping all
+ * threads periodically.
+ */
+static int torture_stutter(void *arg)
+{
+	VERBOSE_TOROUT_STRING("torture_stutter task started");
+	do {
+		if (!torture_must_stop()) {
+			schedule_timeout_interruptible(stutter);
+			ACCESS_ONCE(stutter_pause_test) = 1;
+		}
+		if (!torture_must_stop())
+			schedule_timeout_interruptible(stutter);
+		ACCESS_ONCE(stutter_pause_test) = 0;
+		torture_shutdown_absorb("torture_stutter");
+	} while (!torture_must_stop());
+	torture_kthread_stopping("torture_stutter");
+	return 0;
+}
+
+/*
+ * Initialize and kick off the torture_stutter kthread.
+ */
+int torture_stutter_init(int s)
+{
+	int ret;
+
+	stutter = s;
+	ret = torture_create_kthread(torture_stutter, NULL, stutter_task);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(torture_stutter_init);
+
+/*
+ * Cleanup after the torture_stutter kthread.
+ */
+static void torture_stutter_cleanup(void)
+{
+	if (!stutter_task)
+		return;
+	VERBOSE_TOROUT_STRING("Stopping torture_stutter task");
+	kthread_stop(stutter_task);
+	stutter_task = NULL;
+}
+
+/*
+ * Initialize torture module.  Please note that this is -not- invoked via
+ * the usual module_init() mechanism, but rather by an explicit call from
+ * the client torture module.  This call must be paired with a later
+ * torture_init_end().
+ *
+ * The runnable parameter points to a flag that controls whether or not
+ * the test is currently runnable.  If there is no such flag, pass in NULL.
+ */
+void __init torture_init_begin(char *ttype, bool v, int *runnable)
+{
+	mutex_lock(&fullstop_mutex);
+	torture_type = ttype;
+	verbose = v;
+	torture_runnable = runnable;
+	fullstop = FULLSTOP_DONTSTOP;
+
+}
+EXPORT_SYMBOL_GPL(torture_init_begin);
+
+/*
+ * Tell the torture module that initialization is complete.
+ */
+void __init torture_init_end(void)
+{
+	mutex_unlock(&fullstop_mutex);
+	register_reboot_notifier(&torture_shutdown_nb);
+}
+EXPORT_SYMBOL_GPL(torture_init_end);
+
+/*
+ * Clean up torture module.  Please note that this is -not- invoked via
+ * the usual module_exit() mechanism, but rather by an explicit call from
+ * the client torture module.  Returns true if a race with system shutdown
+ * is detected, otherwise, all kthreads started by functions in this file
+ * will be shut down.
+ *
+ * This must be called before the caller starts shutting down its own
+ * kthreads.
+ */
+bool torture_cleanup(void)
+{
+	mutex_lock(&fullstop_mutex);
+	if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
+		pr_warn("Concurrent rmmod and shutdown illegal!\n");
+		mutex_unlock(&fullstop_mutex);
+		schedule_timeout_uninterruptible(10);
+		return true;
+	}
+	ACCESS_ONCE(fullstop) = FULLSTOP_RMMOD;
+	mutex_unlock(&fullstop_mutex);
+	torture_shutdown_cleanup();
+	torture_shuffle_cleanup();
+	torture_stutter_cleanup();
+	torture_onoff_cleanup();
+	return false;
+}
+EXPORT_SYMBOL_GPL(torture_cleanup);
+
+/*
+ * Is it time for the current torture test to stop?
+ */
+bool torture_must_stop(void)
+{
+	return torture_must_stop_irq() || kthread_should_stop();
+}
+EXPORT_SYMBOL_GPL(torture_must_stop);
+
+/*
+ * Is it time for the current torture test to stop?  This is the irq-safe
+ * version, hence no check for kthread_should_stop().
+ */
+bool torture_must_stop_irq(void)
+{
+	return ACCESS_ONCE(fullstop) != FULLSTOP_DONTSTOP;
+}
+EXPORT_SYMBOL_GPL(torture_must_stop_irq);
+
+/*
+ * Each kthread must wait for kthread_should_stop() before returning from
+ * its top-level function, otherwise segfaults ensue.  This function
+ * prints a "stopping" message and waits for kthread_should_stop(), and
+ * should be called from all torture kthreads immediately prior to
+ * returning.
+ */
+void torture_kthread_stopping(char *title)
+{
+	if (verbose)
+		VERBOSE_TOROUT_STRING(title);
+	while (!kthread_should_stop()) {
+		torture_shutdown_absorb(title);
+		schedule_timeout_uninterruptible(1);
+	}
+}
+EXPORT_SYMBOL_GPL(torture_kthread_stopping);
+
+/*
+ * Create a generic torture kthread that is immediately runnable.  If you
+ * need the kthread to be stopped so that you can do something to it before
+ * it starts, you will need to open-code your own.
+ */
+int _torture_create_kthread(int (*fn)(void *arg), void *arg, char *s, char *m,
+			    char *f, struct task_struct **tp)
+{
+	int ret = 0;
+
+	VERBOSE_TOROUT_STRING(m);
+	*tp = kthread_run(fn, arg, s);
+	if (IS_ERR(*tp)) {
+		ret = PTR_ERR(*tp);
+		VERBOSE_TOROUT_ERRSTRING(f);
+		*tp = NULL;
+	}
+	torture_shuffle_task_register(*tp);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(_torture_create_kthread);
+
+/*
+ * Stop a generic kthread, emitting a message.
+ */
+void _torture_stop_kthread(char *m, struct task_struct **tp)
+{
+	if (*tp == NULL)
+		return;
+	VERBOSE_TOROUT_STRING(m);
+	kthread_stop(*tp);
+	*tp = NULL;
+}
+EXPORT_SYMBOL_GPL(_torture_stop_kthread);
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 015f85aaca08..8639819f6cef 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -424,6 +424,7 @@ config UPROBE_EVENT
 	bool "Enable uprobes-based dynamic events"
 	depends on ARCH_SUPPORTS_UPROBES
 	depends on MMU
+	depends on PERF_EVENTS
 	select UPROBES
 	select PROBE_EVENTS
 	select TRACING
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index b418cb0d7242..c1bd4ada2a04 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -702,6 +702,7 @@ void blk_trace_shutdown(struct request_queue *q)
  * blk_add_trace_rq - Add a trace for a request oriented action
  * @q:		queue the io is for
  * @rq:		the source request
+ * @nr_bytes:	number of completed bytes
  * @what:	the action
  *
  * Description:
@@ -709,7 +710,7 @@ void blk_trace_shutdown(struct request_queue *q)
  *
  **/
 static void blk_add_trace_rq(struct request_queue *q, struct request *rq,
-			     u32 what)
+			     unsigned int nr_bytes, u32 what)
 {
 	struct blk_trace *bt = q->blk_trace;
 
@@ -718,11 +719,11 @@ static void blk_add_trace_rq(struct request_queue *q, struct request *rq,
 
 	if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
 		what |= BLK_TC_ACT(BLK_TC_PC);
-		__blk_add_trace(bt, 0, blk_rq_bytes(rq), rq->cmd_flags,
+		__blk_add_trace(bt, 0, nr_bytes, rq->cmd_flags,
 				what, rq->errors, rq->cmd_len, rq->cmd);
 	} else  {
 		what |= BLK_TC_ACT(BLK_TC_FS);
-		__blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq),
+		__blk_add_trace(bt, blk_rq_pos(rq), nr_bytes,
 				rq->cmd_flags, what, rq->errors, 0, NULL);
 	}
 }
@@ -730,33 +731,34 @@ static void blk_add_trace_rq(struct request_queue *q, struct request *rq,
 static void blk_add_trace_rq_abort(void *ignore,
 				   struct request_queue *q, struct request *rq)
 {
-	blk_add_trace_rq(q, rq, BLK_TA_ABORT);
+	blk_add_trace_rq(q, rq, blk_rq_bytes(rq), BLK_TA_ABORT);
 }
 
 static void blk_add_trace_rq_insert(void *ignore,
 				    struct request_queue *q, struct request *rq)
 {
-	blk_add_trace_rq(q, rq, BLK_TA_INSERT);
+	blk_add_trace_rq(q, rq, blk_rq_bytes(rq), BLK_TA_INSERT);
 }
 
 static void blk_add_trace_rq_issue(void *ignore,
 				   struct request_queue *q, struct request *rq)
 {
-	blk_add_trace_rq(q, rq, BLK_TA_ISSUE);
+	blk_add_trace_rq(q, rq, blk_rq_bytes(rq), BLK_TA_ISSUE);
 }
 
 static void blk_add_trace_rq_requeue(void *ignore,
 				     struct request_queue *q,
 				     struct request *rq)
 {
-	blk_add_trace_rq(q, rq, BLK_TA_REQUEUE);
+	blk_add_trace_rq(q, rq, blk_rq_bytes(rq), BLK_TA_REQUEUE);
 }
 
 static void blk_add_trace_rq_complete(void *ignore,
 				      struct request_queue *q,
-				      struct request *rq)
+				      struct request *rq,
+				      unsigned int nr_bytes)
 {
-	blk_add_trace_rq(q, rq, BLK_TA_COMPLETE);
+	blk_add_trace_rq(q, rq, nr_bytes, BLK_TA_COMPLETE);
 }
 
 /**
@@ -1427,7 +1429,8 @@ static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter)
 	return print_one_line(iter, true);
 }
 
-static int blk_tracer_set_flag(u32 old_flags, u32 bit, int set)
+static int
+blk_tracer_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
 {
 	/* don't output context-info for blk_classic output */
 	if (bit == TRACE_BLK_OPT_CLASSIC) {
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index cd7f76d1eb86..4a54a25afa2f 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -237,14 +237,13 @@ static int control_ops_alloc(struct ftrace_ops *ops)
 	return 0;
 }
 
-static void control_ops_free(struct ftrace_ops *ops)
-{
-	free_percpu(ops->disabled);
-}
-
 static void update_global_ops(void)
 {
-	ftrace_func_t func;
+	ftrace_func_t func = ftrace_global_list_func;
+	void *private = NULL;
+
+	/* The list has its own recursion protection. */
+	global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE;
 
 	/*
 	 * If there's only one function registered, then call that
@@ -254,23 +253,17 @@ static void update_global_ops(void)
 	if (ftrace_global_list == &ftrace_list_end ||
 	    ftrace_global_list->next == &ftrace_list_end) {
 		func = ftrace_global_list->func;
+		private = ftrace_global_list->private;
 		/*
 		 * As we are calling the function directly.
 		 * If it does not have recursion protection,
 		 * the function_trace_op needs to be updated
 		 * accordingly.
 		 */
-		if (ftrace_global_list->flags & FTRACE_OPS_FL_RECURSION_SAFE)
-			global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE;
-		else
+		if (!(ftrace_global_list->flags & FTRACE_OPS_FL_RECURSION_SAFE))
 			global_ops.flags &= ~FTRACE_OPS_FL_RECURSION_SAFE;
-	} else {
-		func = ftrace_global_list_func;
-		/* The list has its own recursion protection. */
-		global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE;
 	}
 
-
 	/* If we filter on pids, update to use the pid function */
 	if (!list_empty(&ftrace_pids)) {
 		set_ftrace_pid_function(func);
@@ -278,6 +271,7 @@ static void update_global_ops(void)
 	}
 
 	global_ops.func = func;
+	global_ops.private = private;
 }
 
 static void ftrace_sync(struct work_struct *work)
@@ -437,6 +431,9 @@ static int remove_ftrace_list_ops(struct ftrace_ops **list,
 
 static int __register_ftrace_function(struct ftrace_ops *ops)
 {
+	if (ops->flags & FTRACE_OPS_FL_DELETED)
+		return -EINVAL;
+
 	if (FTRACE_WARN_ON(ops == &global_ops))
 		return -EINVAL;
 
@@ -1172,8 +1169,6 @@ struct ftrace_page {
 	int			size;
 };
 
-static struct ftrace_page *ftrace_new_pgs;
-
 #define ENTRY_SIZE sizeof(struct dyn_ftrace)
 #define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE)
 
@@ -1560,7 +1555,7 @@ unsigned long ftrace_location(unsigned long ip)
  * the function tracer. It checks the ftrace internal tables to
  * determine if the address belongs or not.
  */
-int ftrace_text_reserved(void *start, void *end)
+int ftrace_text_reserved(const void *start, const void *end)
 {
 	unsigned long ret;
 
@@ -1994,6 +1989,7 @@ int __weak ftrace_arch_code_modify_post_process(void)
 void ftrace_modify_all_code(int command)
 {
 	int update = command & FTRACE_UPDATE_TRACE_FUNC;
+	int err = 0;
 
 	/*
 	 * If the ftrace_caller calls a ftrace_ops func directly,
@@ -2005,8 +2001,11 @@ void ftrace_modify_all_code(int command)
 	 * to make sure the ops are having the right functions
 	 * traced.
 	 */
-	if (update)
-		ftrace_update_ftrace_func(ftrace_ops_list_func);
+	if (update) {
+		err = ftrace_update_ftrace_func(ftrace_ops_list_func);
+		if (FTRACE_WARN_ON(err))
+			return;
+	}
 
 	if (command & FTRACE_UPDATE_CALLS)
 		ftrace_replace_code(1);
@@ -2019,13 +2018,16 @@ void ftrace_modify_all_code(int command)
 		/* If irqs are disabled, we are in stop machine */
 		if (!irqs_disabled())
 			smp_call_function(ftrace_sync_ipi, NULL, 1);
-		ftrace_update_ftrace_func(ftrace_trace_function);
+		err = ftrace_update_ftrace_func(ftrace_trace_function);
+		if (FTRACE_WARN_ON(err))
+			return;
 	}
 
 	if (command & FTRACE_START_FUNC_RET)
-		ftrace_enable_ftrace_graph_caller();
+		err = ftrace_enable_ftrace_graph_caller();
 	else if (command & FTRACE_STOP_FUNC_RET)
-		ftrace_disable_ftrace_graph_caller();
+		err = ftrace_disable_ftrace_graph_caller();
+	FTRACE_WARN_ON(err);
 }
 
 static int __ftrace_modify_code(void *data)
@@ -2093,6 +2095,11 @@ static ftrace_func_t saved_ftrace_func;
 static int ftrace_start_up;
 static int global_start_up;
 
+static void control_ops_free(struct ftrace_ops *ops)
+{
+	free_percpu(ops->disabled);
+}
+
 static void ftrace_startup_enable(int command)
 {
 	if (saved_ftrace_func != ftrace_trace_function) {
@@ -2244,7 +2251,6 @@ static void ftrace_shutdown_sysctl(void)
 }
 
 static cycle_t		ftrace_update_time;
-static unsigned long	ftrace_update_cnt;
 unsigned long		ftrace_update_tot_cnt;
 
 static inline int ops_traces_mod(struct ftrace_ops *ops)
@@ -2300,11 +2306,12 @@ static int referenced_filters(struct dyn_ftrace *rec)
 	return cnt;
 }
 
-static int ftrace_update_code(struct module *mod)
+static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs)
 {
 	struct ftrace_page *pg;
 	struct dyn_ftrace *p;
 	cycle_t start, stop;
+	unsigned long update_cnt = 0;
 	unsigned long ref = 0;
 	bool test = false;
 	int i;
@@ -2330,9 +2337,8 @@ static int ftrace_update_code(struct module *mod)
 	}
 
 	start = ftrace_now(raw_smp_processor_id());
-	ftrace_update_cnt = 0;
 
-	for (pg = ftrace_new_pgs; pg; pg = pg->next) {
+	for (pg = new_pgs; pg; pg = pg->next) {
 
 		for (i = 0; i < pg->index; i++) {
 			int cnt = ref;
@@ -2353,7 +2359,7 @@ static int ftrace_update_code(struct module *mod)
 			if (!ftrace_code_disable(mod, p))
 				break;
 
-			ftrace_update_cnt++;
+			update_cnt++;
 
 			/*
 			 * If the tracing is enabled, go ahead and enable the record.
@@ -2372,11 +2378,9 @@ static int ftrace_update_code(struct module *mod)
 		}
 	}
 
-	ftrace_new_pgs = NULL;
-
 	stop = ftrace_now(raw_smp_processor_id());
 	ftrace_update_time = stop - start;
-	ftrace_update_tot_cnt += ftrace_update_cnt;
+	ftrace_update_tot_cnt += update_cnt;
 
 	return 0;
 }
@@ -2468,22 +2472,6 @@ ftrace_allocate_pages(unsigned long num_to_init)
 	return NULL;
 }
 
-static int __init ftrace_dyn_table_alloc(unsigned long num_to_init)
-{
-	int cnt;
-
-	if (!num_to_init) {
-		pr_info("ftrace: No functions to be traced?\n");
-		return -1;
-	}
-
-	cnt = num_to_init / ENTRIES_PER_PAGE;
-	pr_info("ftrace: allocating %ld entries in %d pages\n",
-		num_to_init, cnt + 1);
-
-	return 0;
-}
-
 #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
 
 struct ftrace_iterator {
@@ -2871,7 +2859,9 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag,
 static int
 ftrace_filter_open(struct inode *inode, struct file *file)
 {
-	return ftrace_regex_open(&global_ops,
+	struct ftrace_ops *ops = inode->i_private;
+
+	return ftrace_regex_open(ops,
 			FTRACE_ITER_FILTER | FTRACE_ITER_DO_HASH,
 			inode, file);
 }
@@ -2879,7 +2869,9 @@ ftrace_filter_open(struct inode *inode, struct file *file)
 static int
 ftrace_notrace_open(struct inode *inode, struct file *file)
 {
-	return ftrace_regex_open(&global_ops, FTRACE_ITER_NOTRACE,
+	struct ftrace_ops *ops = inode->i_private;
+
+	return ftrace_regex_open(ops, FTRACE_ITER_NOTRACE,
 				 inode, file);
 }
 
@@ -4109,6 +4101,36 @@ static const struct file_operations ftrace_graph_notrace_fops = {
 };
 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 
+void ftrace_create_filter_files(struct ftrace_ops *ops,
+				struct dentry *parent)
+{
+
+	trace_create_file("set_ftrace_filter", 0644, parent,
+			  ops, &ftrace_filter_fops);
+
+	trace_create_file("set_ftrace_notrace", 0644, parent,
+			  ops, &ftrace_notrace_fops);
+}
+
+/*
+ * The name "destroy_filter_files" is really a misnomer. Although
+ * in the future, it may actualy delete the files, but this is
+ * really intended to make sure the ops passed in are disabled
+ * and that when this function returns, the caller is free to
+ * free the ops.
+ *
+ * The "destroy" name is only to match the "create" name that this
+ * should be paired with.
+ */
+void ftrace_destroy_filter_files(struct ftrace_ops *ops)
+{
+	mutex_lock(&ftrace_lock);
+	if (ops->flags & FTRACE_OPS_FL_ENABLED)
+		ftrace_shutdown(ops, 0);
+	ops->flags |= FTRACE_OPS_FL_DELETED;
+	mutex_unlock(&ftrace_lock);
+}
+
 static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer)
 {
 
@@ -4118,11 +4140,7 @@ static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer)
 	trace_create_file("enabled_functions", 0444,
 			d_tracer, NULL, &ftrace_enabled_fops);
 
-	trace_create_file("set_ftrace_filter", 0644, d_tracer,
-			NULL, &ftrace_filter_fops);
-
-	trace_create_file("set_ftrace_notrace", 0644, d_tracer,
-				    NULL, &ftrace_notrace_fops);
+	ftrace_create_filter_files(&global_ops, d_tracer);
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 	trace_create_file("set_graph_function", 0444, d_tracer,
@@ -4238,9 +4256,6 @@ static int ftrace_process_locs(struct module *mod,
 	/* Assign the last page to ftrace_pages */
 	ftrace_pages = pg;
 
-	/* These new locations need to be initialized */
-	ftrace_new_pgs = start_pg;
-
 	/*
 	 * We only need to disable interrupts on start up
 	 * because we are modifying code that an interrupt
@@ -4251,7 +4266,7 @@ static int ftrace_process_locs(struct module *mod,
 	 */
 	if (!mod)
 		local_irq_save(flags);
-	ftrace_update_code(mod);
+	ftrace_update_code(mod, start_pg);
 	if (!mod)
 		local_irq_restore(flags);
 	ret = 0;
@@ -4315,16 +4330,11 @@ static void ftrace_init_module(struct module *mod,
 	ftrace_process_locs(mod, start, end);
 }
 
-static int ftrace_module_notify_enter(struct notifier_block *self,
-				      unsigned long val, void *data)
+void ftrace_module_init(struct module *mod)
 {
-	struct module *mod = data;
-
-	if (val == MODULE_STATE_COMING)
-		ftrace_init_module(mod, mod->ftrace_callsites,
-				   mod->ftrace_callsites +
-				   mod->num_ftrace_callsites);
-	return 0;
+	ftrace_init_module(mod, mod->ftrace_callsites,
+			   mod->ftrace_callsites +
+			   mod->num_ftrace_callsites);
 }
 
 static int ftrace_module_notify_exit(struct notifier_block *self,
@@ -4338,11 +4348,6 @@ static int ftrace_module_notify_exit(struct notifier_block *self,
 	return 0;
 }
 #else
-static int ftrace_module_notify_enter(struct notifier_block *self,
-				      unsigned long val, void *data)
-{
-	return 0;
-}
 static int ftrace_module_notify_exit(struct notifier_block *self,
 				     unsigned long val, void *data)
 {
@@ -4350,40 +4355,32 @@ static int ftrace_module_notify_exit(struct notifier_block *self,
 }
 #endif /* CONFIG_MODULES */
 
-struct notifier_block ftrace_module_enter_nb = {
-	.notifier_call = ftrace_module_notify_enter,
-	.priority = INT_MAX,	/* Run before anything that can use kprobes */
-};
-
 struct notifier_block ftrace_module_exit_nb = {
 	.notifier_call = ftrace_module_notify_exit,
 	.priority = INT_MIN,	/* Run after anything that can remove kprobes */
 };
 
-extern unsigned long __start_mcount_loc[];
-extern unsigned long __stop_mcount_loc[];
-
 void __init ftrace_init(void)
 {
-	unsigned long count, addr, flags;
+	extern unsigned long __start_mcount_loc[];
+	extern unsigned long __stop_mcount_loc[];
+	unsigned long count, flags;
 	int ret;
 
-	/* Keep the ftrace pointer to the stub */
-	addr = (unsigned long)ftrace_stub;
-
 	local_irq_save(flags);
-	ftrace_dyn_arch_init(&addr);
+	ret = ftrace_dyn_arch_init();
 	local_irq_restore(flags);
-
-	/* ftrace_dyn_arch_init places the return code in addr */
-	if (addr)
+	if (ret)
 		goto failed;
 
 	count = __stop_mcount_loc - __start_mcount_loc;
-
-	ret = ftrace_dyn_table_alloc(count);
-	if (ret)
+	if (!count) {
+		pr_info("ftrace: No functions to be traced?\n");
 		goto failed;
+	}
+
+	pr_info("ftrace: allocating %ld entries in %ld pages\n",
+		count, count / ENTRIES_PER_PAGE + 1);
 
 	last_ftrace_enabled = ftrace_enabled = 1;
 
@@ -4391,10 +4388,6 @@ void __init ftrace_init(void)
 				  __start_mcount_loc,
 				  __stop_mcount_loc);
 
-	ret = register_module_notifier(&ftrace_module_enter_nb);
-	if (ret)
-		pr_warning("Failed to register trace ftrace module enter notifier\n");
-
 	ret = register_module_notifier(&ftrace_module_exit_nb);
 	if (ret)
 		pr_warning("Failed to register trace ftrace module exit notifier\n");
@@ -4431,7 +4424,13 @@ static inline void ftrace_startup_enable(int command) { }
 			(ops)->flags |= FTRACE_OPS_FL_ENABLED;		\
 		___ret;							\
 	})
-# define ftrace_shutdown(ops, command) __unregister_ftrace_function(ops)
+# define ftrace_shutdown(ops, command)					\
+	({								\
+		int ___ret = __unregister_ftrace_function(ops);		\
+		if (!___ret)						\
+			(ops)->flags &= ~FTRACE_OPS_FL_ENABLED;		\
+		___ret;							\
+	})
 
 # define ftrace_startup_sysctl()	do { } while (0)
 # define ftrace_shutdown_sysctl()	do { } while (0)
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index fc4da2d97f9b..c634868c2921 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -1301,7 +1301,7 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags,
 	 * In that off case, we need to allocate for all possible cpus.
 	 */
 #ifdef CONFIG_HOTPLUG_CPU
-	get_online_cpus();
+	cpu_notifier_register_begin();
 	cpumask_copy(buffer->cpumask, cpu_online_mask);
 #else
 	cpumask_copy(buffer->cpumask, cpu_possible_mask);
@@ -1324,10 +1324,10 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags,
 #ifdef CONFIG_HOTPLUG_CPU
 	buffer->cpu_notify.notifier_call = rb_cpu_notify;
 	buffer->cpu_notify.priority = 0;
-	register_cpu_notifier(&buffer->cpu_notify);
+	__register_cpu_notifier(&buffer->cpu_notify);
+	cpu_notifier_register_done();
 #endif
 
-	put_online_cpus();
 	mutex_init(&buffer->mutex);
 
 	return buffer;
@@ -1341,7 +1341,9 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags,
 
  fail_free_cpumask:
 	free_cpumask_var(buffer->cpumask);
-	put_online_cpus();
+#ifdef CONFIG_HOTPLUG_CPU
+	cpu_notifier_register_done();
+#endif
 
  fail_free_buffer:
 	kfree(buffer);
@@ -1358,16 +1360,17 @@ ring_buffer_free(struct ring_buffer *buffer)
 {
 	int cpu;
 
-	get_online_cpus();
-
 #ifdef CONFIG_HOTPLUG_CPU
-	unregister_cpu_notifier(&buffer->cpu_notify);
+	cpu_notifier_register_begin();
+	__unregister_cpu_notifier(&buffer->cpu_notify);
 #endif
 
 	for_each_buffer_cpu(buffer, cpu)
 		rb_free_cpu_buffer(buffer->buffers[cpu]);
 
-	put_online_cpus();
+#ifdef CONFIG_HOTPLUG_CPU
+	cpu_notifier_register_done();
+#endif
 
 	kfree(buffer->buffers);
 	free_cpumask_var(buffer->cpumask);
diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c
index a5457d577b98..0434ff1b808e 100644
--- a/kernel/trace/ring_buffer_benchmark.c
+++ b/kernel/trace/ring_buffer_benchmark.c
@@ -40,8 +40,8 @@ static int write_iteration = 50;
 module_param(write_iteration, uint, 0644);
 MODULE_PARM_DESC(write_iteration, "# of writes between timestamp readings");
 
-static int producer_nice = 19;
-static int consumer_nice = 19;
+static int producer_nice = MAX_NICE;
+static int consumer_nice = MAX_NICE;
 
 static int producer_fifo = -1;
 static int consumer_fifo = -1;
@@ -308,7 +308,7 @@ static void ring_buffer_producer(void)
 
 	/* Let the user know that the test is running at low priority */
 	if (producer_fifo < 0 && consumer_fifo < 0 &&
-	    producer_nice == 19 && consumer_nice == 19)
+	    producer_nice == MAX_NICE && consumer_nice == MAX_NICE)
 		trace_printk("WARNING!!! This test is running at lowest priority.\n");
 
 	trace_printk("Time:     %lld (usecs)\n", time);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 24c1f2382557..737b0efa1a62 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -73,7 +73,8 @@ static struct tracer_flags dummy_tracer_flags = {
 	.opts = dummy_tracer_opt
 };
 
-static int dummy_set_flag(u32 old_flags, u32 bit, int set)
+static int
+dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
 {
 	return 0;
 }
@@ -118,7 +119,7 @@ enum ftrace_dump_mode ftrace_dump_on_oops;
 /* When set, tracing will stop when a WARN*() is hit */
 int __disable_trace_on_warning;
 
-static int tracing_set_tracer(const char *buf);
+static int tracing_set_tracer(struct trace_array *tr, const char *buf);
 
 #define MAX_TRACER_SIZE		100
 static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata;
@@ -180,6 +181,17 @@ static int __init set_trace_boot_options(char *str)
 }
 __setup("trace_options=", set_trace_boot_options);
 
+static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata;
+static char *trace_boot_clock __initdata;
+
+static int __init set_trace_boot_clock(char *str)
+{
+	strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE);
+	trace_boot_clock = trace_boot_clock_buf;
+	return 0;
+}
+__setup("trace_clock=", set_trace_boot_clock);
+
 
 unsigned long long ns2usecs(cycle_t nsec)
 {
@@ -1230,7 +1242,7 @@ int register_tracer(struct tracer *type)
 
 	printk(KERN_INFO "Starting tracer '%s'\n", type->name);
 	/* Do we want this tracer to start on bootup? */
-	tracing_set_tracer(type->name);
+	tracing_set_tracer(&global_trace, type->name);
 	default_bootup_tracer = NULL;
 	/* disable other selftests, since this will break it. */
 	tracing_selftest_disabled = true;
@@ -3137,27 +3149,52 @@ static int tracing_open(struct inode *inode, struct file *file)
 	return ret;
 }
 
+/*
+ * Some tracers are not suitable for instance buffers.
+ * A tracer is always available for the global array (toplevel)
+ * or if it explicitly states that it is.
+ */
+static bool
+trace_ok_for_array(struct tracer *t, struct trace_array *tr)
+{
+	return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances;
+}
+
+/* Find the next tracer that this trace array may use */
+static struct tracer *
+get_tracer_for_array(struct trace_array *tr, struct tracer *t)
+{
+	while (t && !trace_ok_for_array(t, tr))
+		t = t->next;
+
+	return t;
+}
+
 static void *
 t_next(struct seq_file *m, void *v, loff_t *pos)
 {
+	struct trace_array *tr = m->private;
 	struct tracer *t = v;
 
 	(*pos)++;
 
 	if (t)
-		t = t->next;
+		t = get_tracer_for_array(tr, t->next);
 
 	return t;
 }
 
 static void *t_start(struct seq_file *m, loff_t *pos)
 {
+	struct trace_array *tr = m->private;
 	struct tracer *t;
 	loff_t l = 0;
 
 	mutex_lock(&trace_types_lock);
-	for (t = trace_types; t && l < *pos; t = t_next(m, t, &l))
-		;
+
+	t = get_tracer_for_array(tr, trace_types);
+	for (; t && l < *pos; t = t_next(m, t, &l))
+			;
 
 	return t;
 }
@@ -3192,10 +3229,21 @@ static const struct seq_operations show_traces_seq_ops = {
 
 static int show_traces_open(struct inode *inode, struct file *file)
 {
+	struct trace_array *tr = inode->i_private;
+	struct seq_file *m;
+	int ret;
+
 	if (tracing_disabled)
 		return -ENODEV;
 
-	return seq_open(file, &show_traces_seq_ops);
+	ret = seq_open(file, &show_traces_seq_ops);
+	if (ret)
+		return ret;
+
+	m = file->private_data;
+	m->private = tr;
+
+	return 0;
 }
 
 static ssize_t
@@ -3355,13 +3403,14 @@ static int tracing_trace_options_show(struct seq_file *m, void *v)
 	return 0;
 }
 
-static int __set_tracer_option(struct tracer *trace,
+static int __set_tracer_option(struct trace_array *tr,
 			       struct tracer_flags *tracer_flags,
 			       struct tracer_opt *opts, int neg)
 {
+	struct tracer *trace = tr->current_trace;
 	int ret;
 
-	ret = trace->set_flag(tracer_flags->val, opts->bit, !neg);
+	ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg);
 	if (ret)
 		return ret;
 
@@ -3373,8 +3422,9 @@ static int __set_tracer_option(struct tracer *trace,
 }
 
 /* Try to assign a tracer specific option */
-static int set_tracer_option(struct tracer *trace, char *cmp, int neg)
+static int set_tracer_option(struct trace_array *tr, char *cmp, int neg)
 {
+	struct tracer *trace = tr->current_trace;
 	struct tracer_flags *tracer_flags = trace->flags;
 	struct tracer_opt *opts = NULL;
 	int i;
@@ -3383,8 +3433,7 @@ static int set_tracer_option(struct tracer *trace, char *cmp, int neg)
 		opts = &tracer_flags->opts[i];
 
 		if (strcmp(cmp, opts->name) == 0)
-			return __set_tracer_option(trace, trace->flags,
-						   opts, neg);
+			return __set_tracer_option(tr, trace->flags, opts, neg);
 	}
 
 	return -EINVAL;
@@ -3407,7 +3456,7 @@ int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled)
 
 	/* Give the tracer a chance to approve the change */
 	if (tr->current_trace->flag_changed)
-		if (tr->current_trace->flag_changed(tr->current_trace, mask, !!enabled))
+		if (tr->current_trace->flag_changed(tr, mask, !!enabled))
 			return -EINVAL;
 
 	if (enabled)
@@ -3456,7 +3505,7 @@ static int trace_set_options(struct trace_array *tr, char *option)
 
 	/* If no option could be set, test the specific tracer options */
 	if (!trace_options[i])
-		ret = set_tracer_option(tr->current_trace, cmp, neg);
+		ret = set_tracer_option(tr, cmp, neg);
 
 	mutex_unlock(&trace_types_lock);
 
@@ -3562,6 +3611,8 @@ static const char readme_msg[] =
 #ifdef CONFIG_TRACER_SNAPSHOT
 	"\t\t      snapshot\n"
 #endif
+	"\t\t      dump\n"
+	"\t\t      cpudump\n"
 	"\t     example: echo do_fault:traceoff > set_ftrace_filter\n"
 	"\t              echo do_trap:traceoff:3 > set_ftrace_filter\n"
 	"\t     The first one will disable tracing every time do_fault is hit\n"
@@ -3885,10 +3936,26 @@ create_trace_option_files(struct trace_array *tr, struct tracer *tracer);
 static void
 destroy_trace_option_files(struct trace_option_dentry *topts);
 
-static int tracing_set_tracer(const char *buf)
+/*
+ * Used to clear out the tracer before deletion of an instance.
+ * Must have trace_types_lock held.
+ */
+static void tracing_set_nop(struct trace_array *tr)
+{
+	if (tr->current_trace == &nop_trace)
+		return;
+	
+	tr->current_trace->enabled--;
+
+	if (tr->current_trace->reset)
+		tr->current_trace->reset(tr);
+
+	tr->current_trace = &nop_trace;
+}
+
+static int tracing_set_tracer(struct trace_array *tr, const char *buf)
 {
 	static struct trace_option_dentry *topts;
-	struct trace_array *tr = &global_trace;
 	struct tracer *t;
 #ifdef CONFIG_TRACER_MAX_TRACE
 	bool had_max_tr;
@@ -3916,9 +3983,15 @@ static int tracing_set_tracer(const char *buf)
 	if (t == tr->current_trace)
 		goto out;
 
+	/* Some tracers are only allowed for the top level buffer */
+	if (!trace_ok_for_array(t, tr)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
 	trace_branch_disable();
 
-	tr->current_trace->enabled = false;
+	tr->current_trace->enabled--;
 
 	if (tr->current_trace->reset)
 		tr->current_trace->reset(tr);
@@ -3941,9 +4014,11 @@ static int tracing_set_tracer(const char *buf)
 		free_snapshot(tr);
 	}
 #endif
-	destroy_trace_option_files(topts);
-
-	topts = create_trace_option_files(tr, t);
+	/* Currently, only the top instance has options */
+	if (tr->flags & TRACE_ARRAY_FL_GLOBAL) {
+		destroy_trace_option_files(topts);
+		topts = create_trace_option_files(tr, t);
+	}
 
 #ifdef CONFIG_TRACER_MAX_TRACE
 	if (t->use_max_tr && !had_max_tr) {
@@ -3960,7 +4035,7 @@ static int tracing_set_tracer(const char *buf)
 	}
 
 	tr->current_trace = t;
-	tr->current_trace->enabled = true;
+	tr->current_trace->enabled++;
 	trace_branch_enable(tr);
  out:
 	mutex_unlock(&trace_types_lock);
@@ -3972,6 +4047,7 @@ static ssize_t
 tracing_set_trace_write(struct file *filp, const char __user *ubuf,
 			size_t cnt, loff_t *ppos)
 {
+	struct trace_array *tr = filp->private_data;
 	char buf[MAX_TRACER_SIZE+1];
 	int i;
 	size_t ret;
@@ -3991,7 +4067,7 @@ tracing_set_trace_write(struct file *filp, const char __user *ubuf,
 	for (i = cnt - 1; i > 0 && isspace(buf[i]); i--)
 		buf[i] = 0;
 
-	err = tracing_set_tracer(buf);
+	err = tracing_set_tracer(tr, buf);
 	if (err)
 		return err;
 
@@ -4316,8 +4392,6 @@ static void tracing_spd_release_pipe(struct splice_pipe_desc *spd,
 
 static const struct pipe_buf_operations tracing_pipe_buf_ops = {
 	.can_merge		= 0,
-	.map			= generic_pipe_buf_map,
-	.unmap			= generic_pipe_buf_unmap,
 	.confirm		= generic_pipe_buf_confirm,
 	.release		= generic_pipe_buf_release,
 	.steal			= generic_pipe_buf_steal,
@@ -4412,7 +4486,7 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
 	trace_access_lock(iter->cpu_file);
 
 	/* Fill as many pages as possible. */
-	for (i = 0, rem = len; i < pipe->buffers && rem; i++) {
+	for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) {
 		spd.pages[i] = alloc_page(GFP_KERNEL);
 		if (!spd.pages[i])
 			break;
@@ -4699,25 +4773,10 @@ static int tracing_clock_show(struct seq_file *m, void *v)
 	return 0;
 }
 
-static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf,
-				   size_t cnt, loff_t *fpos)
+static int tracing_set_clock(struct trace_array *tr, const char *clockstr)
 {
-	struct seq_file *m = filp->private_data;
-	struct trace_array *tr = m->private;
-	char buf[64];
-	const char *clockstr;
 	int i;
 
-	if (cnt >= sizeof(buf))
-		return -EINVAL;
-
-	if (copy_from_user(&buf, ubuf, cnt))
-		return -EFAULT;
-
-	buf[cnt] = 0;
-
-	clockstr = strstrip(buf);
-
 	for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) {
 		if (strcmp(trace_clocks[i].name, clockstr) == 0)
 			break;
@@ -4745,6 +4804,32 @@ static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf,
 
 	mutex_unlock(&trace_types_lock);
 
+	return 0;
+}
+
+static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf,
+				   size_t cnt, loff_t *fpos)
+{
+	struct seq_file *m = filp->private_data;
+	struct trace_array *tr = m->private;
+	char buf[64];
+	const char *clockstr;
+	int ret;
+
+	if (cnt >= sizeof(buf))
+		return -EINVAL;
+
+	if (copy_from_user(&buf, ubuf, cnt))
+		return -EFAULT;
+
+	buf[cnt] = 0;
+
+	clockstr = strstrip(buf);
+
+	ret = tracing_set_clock(tr, clockstr);
+	if (ret)
+		return ret;
+
 	*fpos += cnt;
 
 	return cnt;
@@ -5194,8 +5279,6 @@ static void buffer_pipe_buf_get(struct pipe_inode_info *pipe,
 /* Pipe buffer operations for a buffer. */
 static const struct pipe_buf_operations buffer_pipe_buf_ops = {
 	.can_merge		= 0,
-	.map			= generic_pipe_buf_map,
-	.unmap			= generic_pipe_buf_unmap,
 	.confirm		= generic_pipe_buf_confirm,
 	.release		= buffer_pipe_buf_release,
 	.steal			= generic_pipe_buf_steal,
@@ -5271,7 +5354,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
 	trace_access_lock(iter->cpu_file);
 	entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file);
 
-	for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) {
+	for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) {
 		struct page *page;
 		int r;
 
@@ -5705,7 +5788,7 @@ trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt,
 
 	if (!!(topt->flags->val & topt->opt->bit) != val) {
 		mutex_lock(&trace_types_lock);
-		ret = __set_tracer_option(topt->tr->current_trace, topt->flags,
+		ret = __set_tracer_option(topt->tr, topt->flags,
 					  topt->opt, !val);
 		mutex_unlock(&trace_types_lock);
 		if (ret)
@@ -6112,7 +6195,9 @@ static int instance_delete(const char *name)
 
 	list_del(&tr->list);
 
+	tracing_set_nop(tr);
 	event_trace_del_tracer(tr);
+	ftrace_destroy_function_files(tr);
 	debugfs_remove_recursive(tr->dir);
 	free_percpu(tr->trace_buffer.data);
 	ring_buffer_free(tr->trace_buffer.buffer);
@@ -6207,6 +6292,12 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer)
 {
 	int cpu;
 
+	trace_create_file("available_tracers", 0444, d_tracer,
+			tr, &show_traces_fops);
+
+	trace_create_file("current_tracer", 0644, d_tracer,
+			tr, &set_tracer_fops);
+
 	trace_create_file("tracing_cpumask", 0644, d_tracer,
 			  tr, &tracing_cpumask_fops);
 
@@ -6237,6 +6328,9 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer)
 	trace_create_file("tracing_on", 0644, d_tracer,
 			  tr, &rb_simple_fops);
 
+	if (ftrace_create_function_files(tr, d_tracer))
+		WARN(1, "Could not allocate function filter files");
+
 #ifdef CONFIG_TRACER_SNAPSHOT
 	trace_create_file("snapshot", 0644, d_tracer,
 			  tr, &snapshot_fops);
@@ -6259,12 +6353,6 @@ static __init int tracer_init_debugfs(void)
 
 	init_tracer_debugfs(&global_trace, d_tracer);
 
-	trace_create_file("available_tracers", 0444, d_tracer,
-			&global_trace, &show_traces_fops);
-
-	trace_create_file("current_tracer", 0644, d_tracer,
-			&global_trace, &set_tracer_fops);
-
 #ifdef CONFIG_TRACER_MAX_TRACE
 	trace_create_file("tracing_max_latency", 0644, d_tracer,
 			&tracing_max_latency, &tracing_max_lat_fops);
@@ -6527,6 +6615,13 @@ __init static int tracer_alloc_buffers(void)
 
 	trace_init_cmdlines();
 
+	if (trace_boot_clock) {
+		ret = tracing_set_clock(&global_trace, trace_boot_clock);
+		if (ret < 0)
+			pr_warning("Trace clock %s not defined, going back to default\n",
+				   trace_boot_clock);
+	}
+
 	/*
 	 * register_tracer() might reference current_trace, so it
 	 * needs to be set before we register anything. This is
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 02b592f2d4b7..2e29d7ba5a52 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -13,6 +13,7 @@
 #include <linux/hw_breakpoint.h>
 #include <linux/trace_seq.h>
 #include <linux/ftrace_event.h>
+#include <linux/compiler.h>
 
 #ifdef CONFIG_FTRACE_SYSCALLS
 #include <asm/unistd.h>		/* For NR_SYSCALLS	     */
@@ -210,6 +211,11 @@ struct trace_array {
 	struct list_head	events;
 	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
 	int			ref;
+#ifdef CONFIG_FUNCTION_TRACER
+	struct ftrace_ops	*ops;
+	/* function tracing enabled */
+	int			function_enabled;
+#endif
 };
 
 enum {
@@ -355,14 +361,16 @@ struct tracer {
 	void			(*print_header)(struct seq_file *m);
 	enum print_line_t	(*print_line)(struct trace_iterator *iter);
 	/* If you handled the flag setting, return 0 */
-	int			(*set_flag)(u32 old_flags, u32 bit, int set);
+	int			(*set_flag)(struct trace_array *tr,
+					    u32 old_flags, u32 bit, int set);
 	/* Return 0 if OK with change, else return non-zero */
-	int			(*flag_changed)(struct tracer *tracer,
+	int			(*flag_changed)(struct trace_array *tr,
 						u32 mask, int set);
 	struct tracer		*next;
 	struct tracer_flags	*flags;
+	int			enabled;
 	bool			print_max;
-	bool			enabled;
+	bool			allow_instances;
 #ifdef CONFIG_TRACER_MAX_TRACE
 	bool			use_max_tr;
 #endif
@@ -812,13 +820,36 @@ static inline int ftrace_trace_task(struct task_struct *task)
 	return test_tsk_trace_trace(task);
 }
 extern int ftrace_is_dead(void);
+int ftrace_create_function_files(struct trace_array *tr,
+				 struct dentry *parent);
+void ftrace_destroy_function_files(struct trace_array *tr);
 #else
 static inline int ftrace_trace_task(struct task_struct *task)
 {
 	return 1;
 }
 static inline int ftrace_is_dead(void) { return 0; }
-#endif
+static inline int
+ftrace_create_function_files(struct trace_array *tr,
+			     struct dentry *parent)
+{
+	return 0;
+}
+static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
+#endif /* CONFIG_FUNCTION_TRACER */
+
+#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
+void ftrace_create_filter_files(struct ftrace_ops *ops,
+				struct dentry *parent);
+void ftrace_destroy_filter_files(struct ftrace_ops *ops);
+#else
+/*
+ * The ops parameter passed in is usually undefined.
+ * This must be a macro.
+ */
+#define ftrace_create_filter_files(ops, parent) do { } while (0)
+#define ftrace_destroy_filter_files(ops) do { } while (0)
+#endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
 
 int ftrace_event_is_function(struct ftrace_event_call *call);
 
@@ -1249,7 +1280,7 @@ int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
 #undef FTRACE_ENTRY
 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter)	\
 	extern struct ftrace_event_call					\
-	__attribute__((__aligned__(4))) event_##call;
+	__aligned(4) event_##call;
 #undef FTRACE_ENTRY_DUP
 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter)	\
 	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index e854f420e033..c894614de14d 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -31,9 +31,25 @@ static int perf_trace_event_perm(struct ftrace_event_call *tp_event,
 	}
 
 	/* The ftrace function trace is allowed only for root. */
-	if (ftrace_event_is_function(tp_event) &&
-	    perf_paranoid_tracepoint_raw() && !capable(CAP_SYS_ADMIN))
-		return -EPERM;
+	if (ftrace_event_is_function(tp_event)) {
+		if (perf_paranoid_tracepoint_raw() && !capable(CAP_SYS_ADMIN))
+			return -EPERM;
+
+		/*
+		 * We don't allow user space callchains for  function trace
+		 * event, due to issues with page faults while tracing page
+		 * fault handler and its overall trickiness nature.
+		 */
+		if (!p_event->attr.exclude_callchain_user)
+			return -EINVAL;
+
+		/*
+		 * Same reason to disable user stack dump as for user space
+		 * callchains above.
+		 */
+		if (p_event->attr.sample_type & PERF_SAMPLE_STACK_USER)
+			return -EINVAL;
+	}
 
 	/* No tracing, just counting, so no obvious leak */
 	if (!(p_event->attr.sample_type & PERF_SAMPLE_RAW))
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 7b16d40bd64d..3ddfd8f62c05 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -188,29 +188,60 @@ int trace_event_raw_init(struct ftrace_event_call *call)
 }
 EXPORT_SYMBOL_GPL(trace_event_raw_init);
 
+void *ftrace_event_buffer_reserve(struct ftrace_event_buffer *fbuffer,
+				  struct ftrace_event_file *ftrace_file,
+				  unsigned long len)
+{
+	struct ftrace_event_call *event_call = ftrace_file->event_call;
+
+	local_save_flags(fbuffer->flags);
+	fbuffer->pc = preempt_count();
+	fbuffer->ftrace_file = ftrace_file;
+
+	fbuffer->event =
+		trace_event_buffer_lock_reserve(&fbuffer->buffer, ftrace_file,
+						event_call->event.type, len,
+						fbuffer->flags, fbuffer->pc);
+	if (!fbuffer->event)
+		return NULL;
+
+	fbuffer->entry = ring_buffer_event_data(fbuffer->event);
+	return fbuffer->entry;
+}
+EXPORT_SYMBOL_GPL(ftrace_event_buffer_reserve);
+
+void ftrace_event_buffer_commit(struct ftrace_event_buffer *fbuffer)
+{
+	event_trigger_unlock_commit(fbuffer->ftrace_file, fbuffer->buffer,
+				    fbuffer->event, fbuffer->entry,
+				    fbuffer->flags, fbuffer->pc);
+}
+EXPORT_SYMBOL_GPL(ftrace_event_buffer_commit);
+
 int ftrace_event_reg(struct ftrace_event_call *call,
 		     enum trace_reg type, void *data)
 {
 	struct ftrace_event_file *file = data;
 
+	WARN_ON(!(call->flags & TRACE_EVENT_FL_TRACEPOINT));
 	switch (type) {
 	case TRACE_REG_REGISTER:
-		return tracepoint_probe_register(call->name,
+		return tracepoint_probe_register(call->tp,
 						 call->class->probe,
 						 file);
 	case TRACE_REG_UNREGISTER:
-		tracepoint_probe_unregister(call->name,
+		tracepoint_probe_unregister(call->tp,
 					    call->class->probe,
 					    file);
 		return 0;
 
 #ifdef CONFIG_PERF_EVENTS
 	case TRACE_REG_PERF_REGISTER:
-		return tracepoint_probe_register(call->name,
+		return tracepoint_probe_register(call->tp,
 						 call->class->perf_probe,
 						 call);
 	case TRACE_REG_PERF_UNREGISTER:
-		tracepoint_probe_unregister(call->name,
+		tracepoint_probe_unregister(call->tp,
 					    call->class->perf_probe,
 					    call);
 		return 0;
@@ -322,7 +353,7 @@ static int __ftrace_event_enable_disable(struct ftrace_event_file *file,
 			if (ret) {
 				tracing_stop_cmdline_record();
 				pr_info("event trace: Could not enable event "
-					"%s\n", call->name);
+					"%s\n", ftrace_event_name(call));
 				break;
 			}
 			set_bit(FTRACE_EVENT_FL_ENABLED_BIT, &file->flags);
@@ -451,27 +482,29 @@ __ftrace_set_clr_event_nolock(struct trace_array *tr, const char *match,
 {
 	struct ftrace_event_file *file;
 	struct ftrace_event_call *call;
+	const char *name;
 	int ret = -EINVAL;
 
 	list_for_each_entry(file, &tr->events, list) {
 
 		call = file->event_call;
+		name = ftrace_event_name(call);
 
-		if (!call->name || !call->class || !call->class->reg)
+		if (!name || !call->class || !call->class->reg)
 			continue;
 
 		if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
 			continue;
 
 		if (match &&
-		    strcmp(match, call->name) != 0 &&
+		    strcmp(match, name) != 0 &&
 		    strcmp(match, call->class->system) != 0)
 			continue;
 
 		if (sub && strcmp(sub, call->class->system) != 0)
 			continue;
 
-		if (event && strcmp(event, call->name) != 0)
+		if (event && strcmp(event, name) != 0)
 			continue;
 
 		ftrace_event_enable_disable(file, set);
@@ -669,7 +702,7 @@ static int t_show(struct seq_file *m, void *v)
 
 	if (strcmp(call->class->system, TRACE_SYSTEM) != 0)
 		seq_printf(m, "%s:", call->class->system);
-	seq_printf(m, "%s\n", call->name);
+	seq_printf(m, "%s\n", ftrace_event_name(call));
 
 	return 0;
 }
@@ -762,7 +795,7 @@ system_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
 	mutex_lock(&event_mutex);
 	list_for_each_entry(file, &tr->events, list) {
 		call = file->event_call;
-		if (!call->name || !call->class || !call->class->reg)
+		if (!ftrace_event_name(call) || !call->class || !call->class->reg)
 			continue;
 
 		if (system && strcmp(call->class->system, system->name) != 0)
@@ -877,7 +910,7 @@ static int f_show(struct seq_file *m, void *v)
 
 	switch ((unsigned long)v) {
 	case FORMAT_HEADER:
-		seq_printf(m, "name: %s\n", call->name);
+		seq_printf(m, "name: %s\n", ftrace_event_name(call));
 		seq_printf(m, "ID: %d\n", call->event.type);
 		seq_printf(m, "format:\n");
 		return 0;
@@ -1497,6 +1530,7 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file)
 	struct trace_array *tr = file->tr;
 	struct list_head *head;
 	struct dentry *d_events;
+	const char *name;
 	int ret;
 
 	/*
@@ -1510,10 +1544,11 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file)
 	} else
 		d_events = parent;
 
-	file->dir = debugfs_create_dir(call->name, d_events);
+	name = ftrace_event_name(call);
+	file->dir = debugfs_create_dir(name, d_events);
 	if (!file->dir) {
 		pr_warning("Could not create debugfs '%s' directory\n",
-			   call->name);
+			   name);
 		return -1;
 	}
 
@@ -1537,7 +1572,7 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file)
 		ret = call->class->define_fields(call);
 		if (ret < 0) {
 			pr_warning("Could not initialize trace point"
-				   " events/%s\n", call->name);
+				   " events/%s\n", name);
 			return -1;
 		}
 	}
@@ -1601,15 +1636,17 @@ static void event_remove(struct ftrace_event_call *call)
 static int event_init(struct ftrace_event_call *call)
 {
 	int ret = 0;
+	const char *name;
 
-	if (WARN_ON(!call->name))
+	name = ftrace_event_name(call);
+	if (WARN_ON(!name))
 		return -EINVAL;
 
 	if (call->class->raw_init) {
 		ret = call->class->raw_init(call);
 		if (ret < 0 && ret != -ENOSYS)
 			pr_warn("Could not initialize trace events/%s\n",
-				call->name);
+				name);
 	}
 
 	return ret;
@@ -1855,7 +1892,7 @@ __trace_add_event_dirs(struct trace_array *tr)
 		ret = __trace_add_new_event(call, tr);
 		if (ret < 0)
 			pr_warning("Could not create directory for event %s\n",
-				   call->name);
+				   ftrace_event_name(call));
 	}
 }
 
@@ -1864,18 +1901,20 @@ find_event_file(struct trace_array *tr, const char *system,  const char *event)
 {
 	struct ftrace_event_file *file;
 	struct ftrace_event_call *call;
+	const char *name;
 
 	list_for_each_entry(file, &tr->events, list) {
 
 		call = file->event_call;
+		name = ftrace_event_name(call);
 
-		if (!call->name || !call->class || !call->class->reg)
+		if (!name || !call->class || !call->class->reg)
 			continue;
 
 		if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
 			continue;
 
-		if (strcmp(event, call->name) == 0 &&
+		if (strcmp(event, name) == 0 &&
 		    strcmp(system, call->class->system) == 0)
 			return file;
 	}
@@ -1943,7 +1982,7 @@ event_enable_print(struct seq_file *m, unsigned long ip,
 	seq_printf(m, "%s:%s:%s",
 		   data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR,
 		   data->file->event_call->class->system,
-		   data->file->event_call->name);
+		   ftrace_event_name(data->file->event_call));
 
 	if (data->count == -1)
 		seq_printf(m, ":unlimited\n");
@@ -2163,7 +2202,7 @@ __trace_early_add_event_dirs(struct trace_array *tr)
 		ret = event_create_dir(tr->event_dir, file);
 		if (ret < 0)
 			pr_warning("Could not create directory for event %s\n",
-				   file->event_call->name);
+				   ftrace_event_name(file->event_call));
 	}
 }
 
@@ -2187,7 +2226,7 @@ __trace_early_add_events(struct trace_array *tr)
 		ret = __trace_early_add_new_event(call, tr);
 		if (ret < 0)
 			pr_warning("Could not create early event %s\n",
-				   call->name);
+				   ftrace_event_name(call));
 	}
 }
 
@@ -2519,7 +2558,7 @@ static __init void event_trace_self_tests(void)
 			continue;
 #endif
 
-		pr_info("Testing event %s: ", call->name);
+		pr_info("Testing event %s: ", ftrace_event_name(call));
 
 		/*
 		 * If an event is already enabled, someone is using
diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index 8efbb69b04f0..4747b476a030 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -77,7 +77,7 @@ event_triggers_call(struct ftrace_event_file *file, void *rec)
 			data->ops->func(data);
 			continue;
 		}
-		filter = rcu_dereference(data->filter);
+		filter = rcu_dereference_sched(data->filter);
 		if (filter && !filter_match_preds(filter, rec))
 			continue;
 		if (data->cmd_ops->post_trigger) {
@@ -1095,7 +1095,7 @@ event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops,
 	seq_printf(m, "%s:%s:%s",
 		   enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR,
 		   enable_data->file->event_call->class->system,
-		   enable_data->file->event_call->name);
+		   ftrace_event_name(enable_data->file->event_call));
 
 	if (data->count == -1)
 		seq_puts(m, ":unlimited");
diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c
index ee0a5098ac43..d4ddde28a81a 100644
--- a/kernel/trace/trace_export.c
+++ b/kernel/trace/trace_export.c
@@ -173,9 +173,11 @@ struct ftrace_event_class __refdata event_class_ftrace_##call = {	\
 };									\
 									\
 struct ftrace_event_call __used event_##call = {			\
-	.name			= #call,				\
-	.event.type		= etype,				\
 	.class			= &event_class_ftrace_##call,		\
+	{								\
+		.name			= #call,			\
+	},								\
+	.event.type		= etype,				\
 	.print_fmt		= print,				\
 	.flags			= TRACE_EVENT_FL_IGNORE_ENABLE | TRACE_EVENT_FL_USE_CALL_FILTER, \
 };									\
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 38fe1483c508..ffd56351b521 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -13,32 +13,110 @@
 #include <linux/debugfs.h>
 #include <linux/uaccess.h>
 #include <linux/ftrace.h>
+#include <linux/slab.h>
 #include <linux/fs.h>
 
 #include "trace.h"
 
-/* function tracing enabled */
-static int			ftrace_function_enabled;
+static void tracing_start_function_trace(struct trace_array *tr);
+static void tracing_stop_function_trace(struct trace_array *tr);
+static void
+function_trace_call(unsigned long ip, unsigned long parent_ip,
+		    struct ftrace_ops *op, struct pt_regs *pt_regs);
+static void
+function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
+			  struct ftrace_ops *op, struct pt_regs *pt_regs);
+static struct ftrace_ops trace_ops;
+static struct ftrace_ops trace_stack_ops;
+static struct tracer_flags func_flags;
+
+/* Our option */
+enum {
+	TRACE_FUNC_OPT_STACK	= 0x1,
+};
+
+static int allocate_ftrace_ops(struct trace_array *tr)
+{
+	struct ftrace_ops *ops;
+
+	ops = kzalloc(sizeof(*ops), GFP_KERNEL);
+	if (!ops)
+		return -ENOMEM;
+
+	/* Currently only the non stack verision is supported */
+	ops->func = function_trace_call;
+	ops->flags = FTRACE_OPS_FL_RECURSION_SAFE;
 
-static struct trace_array	*func_trace;
+	tr->ops = ops;
+	ops->private = tr;
+	return 0;
+}
+
+
+int ftrace_create_function_files(struct trace_array *tr,
+				 struct dentry *parent)
+{
+	int ret;
+
+	/*
+	 * The top level array uses the "global_ops", and the files are
+	 * created on boot up.
+	 */
+	if (tr->flags & TRACE_ARRAY_FL_GLOBAL)
+		return 0;
 
-static void tracing_start_function_trace(void);
-static void tracing_stop_function_trace(void);
+	ret = allocate_ftrace_ops(tr);
+	if (ret)
+		return ret;
+
+	ftrace_create_filter_files(tr->ops, parent);
+
+	return 0;
+}
+
+void ftrace_destroy_function_files(struct trace_array *tr)
+{
+	ftrace_destroy_filter_files(tr->ops);
+	kfree(tr->ops);
+	tr->ops = NULL;
+}
 
 static int function_trace_init(struct trace_array *tr)
 {
-	func_trace = tr;
+	struct ftrace_ops *ops;
+
+	if (tr->flags & TRACE_ARRAY_FL_GLOBAL) {
+		/* There's only one global tr */
+		if (!trace_ops.private) {
+			trace_ops.private = tr;
+			trace_stack_ops.private = tr;
+		}
+
+		if (func_flags.val & TRACE_FUNC_OPT_STACK)
+			ops = &trace_stack_ops;
+		else
+			ops = &trace_ops;
+		tr->ops = ops;
+	} else if (!tr->ops) {
+		/*
+		 * Instance trace_arrays get their ops allocated
+		 * at instance creation. Unless it failed
+		 * the allocation.
+		 */
+		return -ENOMEM;
+	}
+
 	tr->trace_buffer.cpu = get_cpu();
 	put_cpu();
 
 	tracing_start_cmdline_record();
-	tracing_start_function_trace();
+	tracing_start_function_trace(tr);
 	return 0;
 }
 
 static void function_trace_reset(struct trace_array *tr)
 {
-	tracing_stop_function_trace();
+	tracing_stop_function_trace(tr);
 	tracing_stop_cmdline_record();
 }
 
@@ -47,25 +125,18 @@ static void function_trace_start(struct trace_array *tr)
 	tracing_reset_online_cpus(&tr->trace_buffer);
 }
 
-/* Our option */
-enum {
-	TRACE_FUNC_OPT_STACK	= 0x1,
-};
-
-static struct tracer_flags func_flags;
-
 static void
 function_trace_call(unsigned long ip, unsigned long parent_ip,
 		    struct ftrace_ops *op, struct pt_regs *pt_regs)
 {
-	struct trace_array *tr = func_trace;
+	struct trace_array *tr = op->private;
 	struct trace_array_cpu *data;
 	unsigned long flags;
 	int bit;
 	int cpu;
 	int pc;
 
-	if (unlikely(!ftrace_function_enabled))
+	if (unlikely(!tr->function_enabled))
 		return;
 
 	pc = preempt_count();
@@ -91,14 +162,14 @@ static void
 function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
 			  struct ftrace_ops *op, struct pt_regs *pt_regs)
 {
-	struct trace_array *tr = func_trace;
+	struct trace_array *tr = op->private;
 	struct trace_array_cpu *data;
 	unsigned long flags;
 	long disabled;
 	int cpu;
 	int pc;
 
-	if (unlikely(!ftrace_function_enabled))
+	if (unlikely(!tr->function_enabled))
 		return;
 
 	/*
@@ -128,7 +199,6 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
 	local_irq_restore(flags);
 }
 
-
 static struct ftrace_ops trace_ops __read_mostly =
 {
 	.func = function_trace_call,
@@ -153,29 +223,21 @@ static struct tracer_flags func_flags = {
 	.opts = func_opts
 };
 
-static void tracing_start_function_trace(void)
+static void tracing_start_function_trace(struct trace_array *tr)
 {
-	ftrace_function_enabled = 0;
-
-	if (func_flags.val & TRACE_FUNC_OPT_STACK)
-		register_ftrace_function(&trace_stack_ops);
-	else
-		register_ftrace_function(&trace_ops);
-
-	ftrace_function_enabled = 1;
+	tr->function_enabled = 0;
+	register_ftrace_function(tr->ops);
+	tr->function_enabled = 1;
 }
 
-static void tracing_stop_function_trace(void)
+static void tracing_stop_function_trace(struct trace_array *tr)
 {
-	ftrace_function_enabled = 0;
-
-	if (func_flags.val & TRACE_FUNC_OPT_STACK)
-		unregister_ftrace_function(&trace_stack_ops);
-	else
-		unregister_ftrace_function(&trace_ops);
+	tr->function_enabled = 0;
+	unregister_ftrace_function(tr->ops);
 }
 
-static int func_set_flag(u32 old_flags, u32 bit, int set)
+static int
+func_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
 {
 	switch (bit) {
 	case TRACE_FUNC_OPT_STACK:
@@ -183,12 +245,14 @@ static int func_set_flag(u32 old_flags, u32 bit, int set)
 		if (!!set == !!(func_flags.val & TRACE_FUNC_OPT_STACK))
 			break;
 
+		unregister_ftrace_function(tr->ops);
+
 		if (set) {
-			unregister_ftrace_function(&trace_ops);
-			register_ftrace_function(&trace_stack_ops);
+			tr->ops = &trace_stack_ops;
+			register_ftrace_function(tr->ops);
 		} else {
-			unregister_ftrace_function(&trace_stack_ops);
-			register_ftrace_function(&trace_ops);
+			tr->ops = &trace_ops;
+			register_ftrace_function(tr->ops);
 		}
 
 		break;
@@ -208,6 +272,7 @@ static struct tracer function_trace __tracer_data =
 	.wait_pipe	= poll_wait_pipe,
 	.flags		= &func_flags,
 	.set_flag	= func_set_flag,
+	.allow_instances = true,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest	= trace_selftest_startup_function,
 #endif
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 0b99120d395c..deff11200261 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -1476,7 +1476,8 @@ void graph_trace_close(struct trace_iterator *iter)
 	}
 }
 
-static int func_graph_set_flag(u32 old_flags, u32 bit, int set)
+static int
+func_graph_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
 {
 	if (bit == TRACE_GRAPH_PRINT_IRQS)
 		ftrace_graph_skip_irqs = !set;
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 2aefbee93a6d..8ff02cbb892f 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -160,7 +160,8 @@ static struct ftrace_ops trace_ops __read_mostly =
 #endif /* CONFIG_FUNCTION_TRACER */
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
-static int irqsoff_set_flag(u32 old_flags, u32 bit, int set)
+static int
+irqsoff_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
 {
 	int cpu;
 
@@ -266,7 +267,8 @@ __trace_function(struct trace_array *tr,
 #else
 #define __trace_function trace_function
 
-static int irqsoff_set_flag(u32 old_flags, u32 bit, int set)
+static int
+irqsoff_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
 {
 	return -EINVAL;
 }
@@ -498,14 +500,14 @@ void trace_hardirqs_off(void)
 }
 EXPORT_SYMBOL(trace_hardirqs_off);
 
-void trace_hardirqs_on_caller(unsigned long caller_addr)
+__visible void trace_hardirqs_on_caller(unsigned long caller_addr)
 {
 	if (!preempt_trace() && irq_trace())
 		stop_critical_timing(CALLER_ADDR0, caller_addr);
 }
 EXPORT_SYMBOL(trace_hardirqs_on_caller);
 
-void trace_hardirqs_off_caller(unsigned long caller_addr)
+__visible void trace_hardirqs_off_caller(unsigned long caller_addr)
 {
 	if (!preempt_trace() && irq_trace())
 		start_critical_timing(CALLER_ADDR0, caller_addr);
@@ -570,8 +572,10 @@ static void irqsoff_function_set(int set)
 		unregister_irqsoff_function(is_graph());
 }
 
-static int irqsoff_flag_changed(struct tracer *tracer, u32 mask, int set)
+static int irqsoff_flag_changed(struct trace_array *tr, u32 mask, int set)
 {
+	struct tracer *tracer = tr->current_trace;
+
 	if (mask & TRACE_ITER_FUNCTION)
 		irqsoff_function_set(set);
 
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index bdbae450c13e..903ae28962be 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -35,11 +35,6 @@ struct trace_kprobe {
 	struct trace_probe	tp;
 };
 
-struct event_file_link {
-	struct ftrace_event_file	*file;
-	struct list_head		list;
-};
-
 #define SIZEOF_TRACE_KPROBE(n)				\
 	(offsetof(struct trace_kprobe, tp.args) +	\
 	(sizeof(struct probe_arg) * (n)))
@@ -346,7 +341,7 @@ static struct trace_kprobe *find_trace_kprobe(const char *event,
 	struct trace_kprobe *tk;
 
 	list_for_each_entry(tk, &probe_list, list)
-		if (strcmp(tk->tp.call.name, event) == 0 &&
+		if (strcmp(ftrace_event_name(&tk->tp.call), event) == 0 &&
 		    strcmp(tk->tp.call.class->system, group) == 0)
 			return tk;
 	return NULL;
@@ -387,18 +382,6 @@ enable_trace_kprobe(struct trace_kprobe *tk, struct ftrace_event_file *file)
 	return ret;
 }
 
-static struct event_file_link *
-find_event_file_link(struct trace_probe *tp, struct ftrace_event_file *file)
-{
-	struct event_file_link *link;
-
-	list_for_each_entry(link, &tp->files, list)
-		if (link->file == file)
-			return link;
-
-	return NULL;
-}
-
 /*
  * Disable trace_probe
  * if the file is NULL, disable "perf" handler, or disable "trace" handler.
@@ -533,7 +516,8 @@ static int register_trace_kprobe(struct trace_kprobe *tk)
 	mutex_lock(&probe_lock);
 
 	/* Delete old (same name) event if exist */
-	old_tk = find_trace_kprobe(tk->tp.call.name, tk->tp.call.class->system);
+	old_tk = find_trace_kprobe(ftrace_event_name(&tk->tp.call),
+			tk->tp.call.class->system);
 	if (old_tk) {
 		ret = unregister_trace_kprobe(old_tk);
 		if (ret < 0)
@@ -581,7 +565,8 @@ static int trace_kprobe_module_callback(struct notifier_block *nb,
 			if (ret)
 				pr_warning("Failed to re-register probe %s on"
 					   "%s: %d\n",
-					   tk->tp.call.name, mod->name, ret);
+					   ftrace_event_name(&tk->tp.call),
+					   mod->name, ret);
 		}
 	}
 	mutex_unlock(&probe_lock);
@@ -835,7 +820,8 @@ static int probes_seq_show(struct seq_file *m, void *v)
 	int i;
 
 	seq_printf(m, "%c", trace_kprobe_is_return(tk) ? 'r' : 'p');
-	seq_printf(m, ":%s/%s", tk->tp.call.class->system, tk->tp.call.name);
+	seq_printf(m, ":%s/%s", tk->tp.call.class->system,
+			ftrace_event_name(&tk->tp.call));
 
 	if (!tk->symbol)
 		seq_printf(m, " 0x%p", tk->rp.kp.addr);
@@ -893,7 +879,8 @@ static int probes_profile_seq_show(struct seq_file *m, void *v)
 {
 	struct trace_kprobe *tk = v;
 
-	seq_printf(m, "  %-44s %15lu %15lu\n", tk->tp.call.name, tk->nhit,
+	seq_printf(m, "  %-44s %15lu %15lu\n",
+		   ftrace_event_name(&tk->tp.call), tk->nhit,
 		   tk->rp.kp.nmissed);
 
 	return 0;
@@ -1028,7 +1015,7 @@ print_kprobe_event(struct trace_iterator *iter, int flags,
 	field = (struct kprobe_trace_entry_head *)iter->ent;
 	tp = container_of(event, struct trace_probe, call.event);
 
-	if (!trace_seq_printf(s, "%s: (", tp->call.name))
+	if (!trace_seq_printf(s, "%s: (", ftrace_event_name(&tp->call)))
 		goto partial;
 
 	if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET))
@@ -1064,7 +1051,7 @@ print_kretprobe_event(struct trace_iterator *iter, int flags,
 	field = (struct kretprobe_trace_entry_head *)iter->ent;
 	tp = container_of(event, struct trace_probe, call.event);
 
-	if (!trace_seq_printf(s, "%s: (", tp->call.name))
+	if (!trace_seq_printf(s, "%s: (", ftrace_event_name(&tp->call)))
 		goto partial;
 
 	if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET))
@@ -1303,7 +1290,8 @@ static int register_kprobe_event(struct trace_kprobe *tk)
 	call->data = tk;
 	ret = trace_add_event_call(call);
 	if (ret) {
-		pr_info("Failed to register kprobe event: %s\n", call->name);
+		pr_info("Failed to register kprobe event: %s\n",
+			ftrace_event_name(call));
 		kfree(call->print_fmt);
 		unregister_ftrace_event(&call->event);
 	}
diff --git a/kernel/trace/trace_nop.c b/kernel/trace/trace_nop.c
index 394f94417e2f..69a5cc94c01a 100644
--- a/kernel/trace/trace_nop.c
+++ b/kernel/trace/trace_nop.c
@@ -62,7 +62,7 @@ static void nop_trace_reset(struct trace_array *tr)
  * If you don't implement it, then the flag setting will be
  * automatically accepted.
  */
-static int nop_set_flag(u32 old_flags, u32 bit, int set)
+static int nop_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
 {
 	/*
 	 * Note that you don't need to update nop_flags.val yourself.
@@ -96,6 +96,7 @@ struct tracer nop_trace __read_mostly =
 	.selftest	= trace_selftest_startup_nop,
 #endif
 	.flags		= &nop_flags,
-	.set_flag	= nop_set_flag
+	.set_flag	= nop_set_flag,
+	.allow_instances = true,
 };
 
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index ed32284fbe32..a436de18aa99 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -431,7 +431,7 @@ int ftrace_raw_output_prep(struct trace_iterator *iter,
 	}
 
 	trace_seq_init(p);
-	ret = trace_seq_printf(s, "%s: ", event->name);
+	ret = trace_seq_printf(s, "%s: ", ftrace_event_name(event));
 	if (!ret)
 		return TRACE_TYPE_PARTIAL_LINE;
 
@@ -439,6 +439,37 @@ int ftrace_raw_output_prep(struct trace_iterator *iter,
 }
 EXPORT_SYMBOL(ftrace_raw_output_prep);
 
+static int ftrace_output_raw(struct trace_iterator *iter, char *name,
+			     char *fmt, va_list ap)
+{
+	struct trace_seq *s = &iter->seq;
+	int ret;
+
+	ret = trace_seq_printf(s, "%s: ", name);
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	ret = trace_seq_vprintf(s, fmt, ap);
+
+	if (!ret)
+		return TRACE_TYPE_PARTIAL_LINE;
+
+	return TRACE_TYPE_HANDLED;
+}
+
+int ftrace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
+{
+	va_list ap;
+	int ret;
+
+	va_start(ap, fmt);
+	ret = ftrace_output_raw(iter, name, fmt, ap);
+	va_end(ap);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(ftrace_output_call);
+
 #ifdef CONFIG_KRETPROBES
 static inline const char *kretprobed(const char *name)
 {
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index b73574a5f429..fb1ab5dfbd42 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -288,6 +288,11 @@ struct trace_probe {
 	struct probe_arg		args[];
 };
 
+struct event_file_link {
+	struct ftrace_event_file	*file;
+	struct list_head		list;
+};
+
 static inline bool trace_probe_is_enabled(struct trace_probe *tp)
 {
 	return !!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE));
@@ -316,6 +321,18 @@ static inline int is_good_name(const char *name)
 	return 1;
 }
 
+static inline struct event_file_link *
+find_event_file_link(struct trace_probe *tp, struct ftrace_event_file *file)
+{
+	struct event_file_link *link;
+
+	list_for_each_entry(link, &tp->files, list)
+		if (link->file == file)
+			return link;
+
+	return NULL;
+}
+
 extern int traceprobe_parse_probe_arg(char *arg, ssize_t *size,
 		   struct probe_arg *parg, bool is_return, bool is_kprobe);
 
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index 6e32635e5e57..e14da5e97a69 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -179,8 +179,10 @@ static void wakeup_function_set(int set)
 		unregister_wakeup_function(is_graph());
 }
 
-static int wakeup_flag_changed(struct tracer *tracer, u32 mask, int set)
+static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set)
 {
+	struct tracer *tracer = tr->current_trace;
+
 	if (mask & TRACE_ITER_FUNCTION)
 		wakeup_function_set(set);
 
@@ -209,7 +211,8 @@ static void stop_func_tracer(int graph)
 }
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
-static int wakeup_set_flag(u32 old_flags, u32 bit, int set)
+static int
+wakeup_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
 {
 
 	if (!(bit & TRACE_DISPLAY_GRAPH))
@@ -311,7 +314,8 @@ __trace_function(struct trace_array *tr,
 #else
 #define __trace_function trace_function
 
-static int wakeup_set_flag(u32 old_flags, u32 bit, int set)
+static int
+wakeup_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
 {
 	return -EINVAL;
 }
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index e6be585cf06a..21b320e5d163 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -13,6 +13,7 @@
 #include <linux/sysctl.h>
 #include <linux/init.h>
 #include <linux/fs.h>
+#include <linux/magic.h>
 
 #include <asm/setup.h>
 
@@ -144,6 +145,8 @@ check_stack(unsigned long ip, unsigned long *stack)
 			i++;
 	}
 
+	BUG_ON(current != &init_task &&
+		*(end_of_stack(current)) != STACK_END_MAGIC);
  out:
 	arch_spin_unlock(&max_stack_lock);
 	local_irq_restore(flags);
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 79e52d93860b..c082a7441345 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -260,6 +260,7 @@ alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret)
 		goto error;
 
 	INIT_LIST_HEAD(&tu->list);
+	INIT_LIST_HEAD(&tu->tp.files);
 	tu->consumer.handler = uprobe_dispatcher;
 	if (is_ret)
 		tu->consumer.ret_handler = uretprobe_dispatcher;
@@ -293,7 +294,7 @@ static struct trace_uprobe *find_probe_event(const char *event, const char *grou
 	struct trace_uprobe *tu;
 
 	list_for_each_entry(tu, &uprobe_list, list)
-		if (strcmp(tu->tp.call.name, event) == 0 &&
+		if (strcmp(ftrace_event_name(&tu->tp.call), event) == 0 &&
 		    strcmp(tu->tp.call.class->system, group) == 0)
 			return tu;
 
@@ -323,7 +324,8 @@ static int register_trace_uprobe(struct trace_uprobe *tu)
 	mutex_lock(&uprobe_lock);
 
 	/* register as an event */
-	old_tu = find_probe_event(tu->tp.call.name, tu->tp.call.class->system);
+	old_tu = find_probe_event(ftrace_event_name(&tu->tp.call),
+			tu->tp.call.class->system);
 	if (old_tu) {
 		/* delete old event */
 		ret = unregister_trace_uprobe(old_tu);
@@ -598,7 +600,8 @@ static int probes_seq_show(struct seq_file *m, void *v)
 	char c = is_ret_probe(tu) ? 'r' : 'p';
 	int i;
 
-	seq_printf(m, "%c:%s/%s", c, tu->tp.call.class->system, tu->tp.call.name);
+	seq_printf(m, "%c:%s/%s", c, tu->tp.call.class->system,
+			ftrace_event_name(&tu->tp.call));
 	seq_printf(m, " %s:0x%p", tu->filename, (void *)tu->offset);
 
 	for (i = 0; i < tu->tp.nr_args; i++)
@@ -648,7 +651,8 @@ static int probes_profile_seq_show(struct seq_file *m, void *v)
 {
 	struct trace_uprobe *tu = v;
 
-	seq_printf(m, "  %s %-44s %15lu\n", tu->filename, tu->tp.call.name, tu->nhit);
+	seq_printf(m, "  %s %-44s %15lu\n", tu->filename,
+			ftrace_event_name(&tu->tp.call), tu->nhit);
 	return 0;
 }
 
@@ -728,9 +732,15 @@ static int uprobe_buffer_enable(void)
 
 static void uprobe_buffer_disable(void)
 {
+	int cpu;
+
 	BUG_ON(!mutex_is_locked(&event_mutex));
 
 	if (--uprobe_buffer_refcnt == 0) {
+		for_each_possible_cpu(cpu)
+			free_page((unsigned long)per_cpu_ptr(uprobe_cpu_buffer,
+							     cpu)->buf);
+
 		free_percpu(uprobe_cpu_buffer);
 		uprobe_cpu_buffer = NULL;
 	}
@@ -758,31 +768,32 @@ static void uprobe_buffer_put(struct uprobe_cpu_buffer *ucb)
 	mutex_unlock(&ucb->mutex);
 }
 
-static void uprobe_trace_print(struct trace_uprobe *tu,
-				unsigned long func, struct pt_regs *regs)
+static void __uprobe_trace_func(struct trace_uprobe *tu,
+				unsigned long func, struct pt_regs *regs,
+				struct uprobe_cpu_buffer *ucb, int dsize,
+				struct ftrace_event_file *ftrace_file)
 {
 	struct uprobe_trace_entry_head *entry;
 	struct ring_buffer_event *event;
 	struct ring_buffer *buffer;
-	struct uprobe_cpu_buffer *ucb;
 	void *data;
-	int size, dsize, esize;
+	int size, esize;
 	struct ftrace_event_call *call = &tu->tp.call;
 
-	dsize = __get_data_size(&tu->tp, regs);
-	esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
+	WARN_ON(call != ftrace_file->event_call);
 
-	if (WARN_ON_ONCE(!uprobe_cpu_buffer || tu->tp.size + dsize > PAGE_SIZE))
+	if (WARN_ON_ONCE(tu->tp.size + dsize > PAGE_SIZE))
 		return;
 
-	ucb = uprobe_buffer_get();
-	store_trace_args(esize, &tu->tp, regs, ucb->buf, dsize);
+	if (ftrace_trigger_soft_disabled(ftrace_file))
+		return;
 
+	esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
 	size = esize + tu->tp.size + dsize;
-	event = trace_current_buffer_lock_reserve(&buffer, call->event.type,
-						  size, 0, 0);
+	event = trace_event_buffer_lock_reserve(&buffer, ftrace_file,
+						call->event.type, size, 0, 0);
 	if (!event)
-		goto out;
+		return;
 
 	entry = ring_buffer_event_data(event);
 	if (is_ret_probe(tu)) {
@@ -796,25 +807,36 @@ static void uprobe_trace_print(struct trace_uprobe *tu,
 
 	memcpy(data, ucb->buf, tu->tp.size + dsize);
 
-	if (!call_filter_check_discard(call, entry, buffer, event))
-		trace_buffer_unlock_commit(buffer, event, 0, 0);
-
-out:
-	uprobe_buffer_put(ucb);
+	event_trigger_unlock_commit(ftrace_file, buffer, event, entry, 0, 0);
 }
 
 /* uprobe handler */
-static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs)
+static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs,
+			     struct uprobe_cpu_buffer *ucb, int dsize)
 {
-	if (!is_ret_probe(tu))
-		uprobe_trace_print(tu, 0, regs);
+	struct event_file_link *link;
+
+	if (is_ret_probe(tu))
+		return 0;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(link, &tu->tp.files, list)
+		__uprobe_trace_func(tu, 0, regs, ucb, dsize, link->file);
+	rcu_read_unlock();
+
 	return 0;
 }
 
 static void uretprobe_trace_func(struct trace_uprobe *tu, unsigned long func,
-				struct pt_regs *regs)
+				 struct pt_regs *regs,
+				 struct uprobe_cpu_buffer *ucb, int dsize)
 {
-	uprobe_trace_print(tu, func, regs);
+	struct event_file_link *link;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(link, &tu->tp.files, list)
+		__uprobe_trace_func(tu, func, regs, ucb, dsize, link->file);
+	rcu_read_unlock();
 }
 
 /* Event entry printers */
@@ -831,12 +853,14 @@ print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *e
 	tu = container_of(event, struct trace_uprobe, tp.call.event);
 
 	if (is_ret_probe(tu)) {
-		if (!trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)", tu->tp.call.name,
+		if (!trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)",
+					ftrace_event_name(&tu->tp.call),
 					entry->vaddr[1], entry->vaddr[0]))
 			goto partial;
 		data = DATAOF_TRACE_ENTRY(entry, true);
 	} else {
-		if (!trace_seq_printf(s, "%s: (0x%lx)", tu->tp.call.name,
+		if (!trace_seq_printf(s, "%s: (0x%lx)",
+					ftrace_event_name(&tu->tp.call),
 					entry->vaddr[0]))
 			goto partial;
 		data = DATAOF_TRACE_ENTRY(entry, false);
@@ -861,12 +885,24 @@ typedef bool (*filter_func_t)(struct uprobe_consumer *self,
 				struct mm_struct *mm);
 
 static int
-probe_event_enable(struct trace_uprobe *tu, int flag, filter_func_t filter)
+probe_event_enable(struct trace_uprobe *tu, struct ftrace_event_file *file,
+		   filter_func_t filter)
 {
-	int ret = 0;
+	bool enabled = trace_probe_is_enabled(&tu->tp);
+	struct event_file_link *link = NULL;
+	int ret;
+
+	if (file) {
+		link = kmalloc(sizeof(*link), GFP_KERNEL);
+		if (!link)
+			return -ENOMEM;
 
-	if (trace_probe_is_enabled(&tu->tp))
-		return -EINTR;
+		link->file = file;
+		list_add_tail_rcu(&link->list, &tu->tp.files);
+
+		tu->tp.flags |= TP_FLAG_TRACE;
+	} else
+		tu->tp.flags |= TP_FLAG_PROFILE;
 
 	ret = uprobe_buffer_enable();
 	if (ret < 0)
@@ -874,24 +910,49 @@ probe_event_enable(struct trace_uprobe *tu, int flag, filter_func_t filter)
 
 	WARN_ON(!uprobe_filter_is_empty(&tu->filter));
 
-	tu->tp.flags |= flag;
+	if (enabled)
+		return 0;
+
 	tu->consumer.filter = filter;
 	ret = uprobe_register(tu->inode, tu->offset, &tu->consumer);
-	if (ret)
-		tu->tp.flags &= ~flag;
+	if (ret) {
+		if (file) {
+			list_del(&link->list);
+			kfree(link);
+			tu->tp.flags &= ~TP_FLAG_TRACE;
+		} else
+			tu->tp.flags &= ~TP_FLAG_PROFILE;
+	}
 
 	return ret;
 }
 
-static void probe_event_disable(struct trace_uprobe *tu, int flag)
+static void
+probe_event_disable(struct trace_uprobe *tu, struct ftrace_event_file *file)
 {
 	if (!trace_probe_is_enabled(&tu->tp))
 		return;
 
+	if (file) {
+		struct event_file_link *link;
+
+		link = find_event_file_link(&tu->tp, file);
+		if (!link)
+			return;
+
+		list_del_rcu(&link->list);
+		/* synchronize with u{,ret}probe_trace_func */
+		synchronize_sched();
+		kfree(link);
+
+		if (!list_empty(&tu->tp.files))
+			return;
+	}
+
 	WARN_ON(!uprobe_filter_is_empty(&tu->filter));
 
 	uprobe_unregister(tu->inode, tu->offset, &tu->consumer);
-	tu->tp.flags &= ~flag;
+	tu->tp.flags &= file ? ~TP_FLAG_TRACE : ~TP_FLAG_PROFILE;
 
 	uprobe_buffer_disable();
 }
@@ -1014,31 +1075,24 @@ static bool uprobe_perf_filter(struct uprobe_consumer *uc,
 	return ret;
 }
 
-static void uprobe_perf_print(struct trace_uprobe *tu,
-				unsigned long func, struct pt_regs *regs)
+static void __uprobe_perf_func(struct trace_uprobe *tu,
+			       unsigned long func, struct pt_regs *regs,
+			       struct uprobe_cpu_buffer *ucb, int dsize)
 {
 	struct ftrace_event_call *call = &tu->tp.call;
 	struct uprobe_trace_entry_head *entry;
 	struct hlist_head *head;
-	struct uprobe_cpu_buffer *ucb;
 	void *data;
-	int size, dsize, esize;
+	int size, esize;
 	int rctx;
 
-	dsize = __get_data_size(&tu->tp, regs);
 	esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
 
-	if (WARN_ON_ONCE(!uprobe_cpu_buffer))
-		return;
-
 	size = esize + tu->tp.size + dsize;
 	size = ALIGN(size + sizeof(u32), sizeof(u64)) - sizeof(u32);
 	if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, "profile buffer not large enough"))
 		return;
 
-	ucb = uprobe_buffer_get();
-	store_trace_args(esize, &tu->tp, regs, ucb->buf, dsize);
-
 	preempt_disable();
 	head = this_cpu_ptr(call->perf_events);
 	if (hlist_empty(head))
@@ -1068,46 +1122,49 @@ static void uprobe_perf_print(struct trace_uprobe *tu,
 	perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL);
  out:
 	preempt_enable();
-	uprobe_buffer_put(ucb);
 }
 
 /* uprobe profile handler */
-static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs)
+static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs,
+			    struct uprobe_cpu_buffer *ucb, int dsize)
 {
 	if (!uprobe_perf_filter(&tu->consumer, 0, current->mm))
 		return UPROBE_HANDLER_REMOVE;
 
 	if (!is_ret_probe(tu))
-		uprobe_perf_print(tu, 0, regs);
+		__uprobe_perf_func(tu, 0, regs, ucb, dsize);
 	return 0;
 }
 
 static void uretprobe_perf_func(struct trace_uprobe *tu, unsigned long func,
-				struct pt_regs *regs)
+				struct pt_regs *regs,
+				struct uprobe_cpu_buffer *ucb, int dsize)
 {
-	uprobe_perf_print(tu, func, regs);
+	__uprobe_perf_func(tu, func, regs, ucb, dsize);
 }
 #endif	/* CONFIG_PERF_EVENTS */
 
-static
-int trace_uprobe_register(struct ftrace_event_call *event, enum trace_reg type, void *data)
+static int
+trace_uprobe_register(struct ftrace_event_call *event, enum trace_reg type,
+		      void *data)
 {
 	struct trace_uprobe *tu = event->data;
+	struct ftrace_event_file *file = data;
 
 	switch (type) {
 	case TRACE_REG_REGISTER:
-		return probe_event_enable(tu, TP_FLAG_TRACE, NULL);
+		return probe_event_enable(tu, file, NULL);
 
 	case TRACE_REG_UNREGISTER:
-		probe_event_disable(tu, TP_FLAG_TRACE);
+		probe_event_disable(tu, file);
 		return 0;
 
 #ifdef CONFIG_PERF_EVENTS
 	case TRACE_REG_PERF_REGISTER:
-		return probe_event_enable(tu, TP_FLAG_PROFILE, uprobe_perf_filter);
+		return probe_event_enable(tu, NULL, uprobe_perf_filter);
 
 	case TRACE_REG_PERF_UNREGISTER:
-		probe_event_disable(tu, TP_FLAG_PROFILE);
+		probe_event_disable(tu, NULL);
 		return 0;
 
 	case TRACE_REG_PERF_OPEN:
@@ -1127,8 +1184,11 @@ static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs)
 {
 	struct trace_uprobe *tu;
 	struct uprobe_dispatch_data udd;
+	struct uprobe_cpu_buffer *ucb;
+	int dsize, esize;
 	int ret = 0;
 
+
 	tu = container_of(con, struct trace_uprobe, consumer);
 	tu->nhit++;
 
@@ -1137,13 +1197,29 @@ static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs)
 
 	current->utask->vaddr = (unsigned long) &udd;
 
+#ifdef CONFIG_PERF_EVENTS
+	if ((tu->tp.flags & TP_FLAG_TRACE) == 0 &&
+	    !uprobe_perf_filter(&tu->consumer, 0, current->mm))
+		return UPROBE_HANDLER_REMOVE;
+#endif
+
+	if (WARN_ON_ONCE(!uprobe_cpu_buffer))
+		return 0;
+
+	dsize = __get_data_size(&tu->tp, regs);
+	esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
+
+	ucb = uprobe_buffer_get();
+	store_trace_args(esize, &tu->tp, regs, ucb->buf, dsize);
+
 	if (tu->tp.flags & TP_FLAG_TRACE)
-		ret |= uprobe_trace_func(tu, regs);
+		ret |= uprobe_trace_func(tu, regs, ucb, dsize);
 
 #ifdef CONFIG_PERF_EVENTS
 	if (tu->tp.flags & TP_FLAG_PROFILE)
-		ret |= uprobe_perf_func(tu, regs);
+		ret |= uprobe_perf_func(tu, regs, ucb, dsize);
 #endif
+	uprobe_buffer_put(ucb);
 	return ret;
 }
 
@@ -1152,6 +1228,8 @@ static int uretprobe_dispatcher(struct uprobe_consumer *con,
 {
 	struct trace_uprobe *tu;
 	struct uprobe_dispatch_data udd;
+	struct uprobe_cpu_buffer *ucb;
+	int dsize, esize;
 
 	tu = container_of(con, struct trace_uprobe, consumer);
 
@@ -1160,13 +1238,23 @@ static int uretprobe_dispatcher(struct uprobe_consumer *con,
 
 	current->utask->vaddr = (unsigned long) &udd;
 
+	if (WARN_ON_ONCE(!uprobe_cpu_buffer))
+		return 0;
+
+	dsize = __get_data_size(&tu->tp, regs);
+	esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
+
+	ucb = uprobe_buffer_get();
+	store_trace_args(esize, &tu->tp, regs, ucb->buf, dsize);
+
 	if (tu->tp.flags & TP_FLAG_TRACE)
-		uretprobe_trace_func(tu, func, regs);
+		uretprobe_trace_func(tu, func, regs, ucb, dsize);
 
 #ifdef CONFIG_PERF_EVENTS
 	if (tu->tp.flags & TP_FLAG_PROFILE)
-		uretprobe_perf_func(tu, func, regs);
+		uretprobe_perf_func(tu, func, regs, ucb, dsize);
 #endif
+	uprobe_buffer_put(ucb);
 	return 0;
 }
 
@@ -1198,7 +1286,8 @@ static int register_uprobe_event(struct trace_uprobe *tu)
 	ret = trace_add_event_call(call);
 
 	if (ret) {
-		pr_info("Failed to register uprobe event: %s\n", call->name);
+		pr_info("Failed to register uprobe event: %s\n",
+			ftrace_event_name(call));
 		kfree(call->print_fmt);
 		unregister_ftrace_event(&call->event);
 	}
diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index 031cc5655a51..6620e5837ce2 100644
--- a/kernel/tracepoint.c
+++ b/kernel/tracepoint.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2008 Mathieu Desnoyers
+ * Copyright (C) 2008-2014 Mathieu Desnoyers
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -33,43 +33,29 @@ extern struct tracepoint * const __stop___tracepoints_ptrs[];
 /* Set to 1 to enable tracepoint debug output */
 static const int tracepoint_debug;
 
+#ifdef CONFIG_MODULES
 /*
- * Tracepoints mutex protects the builtin and module tracepoints and the hash
- * table, as well as the local module list.
+ * Tracepoint module list mutex protects the local module list.
  */
-static DEFINE_MUTEX(tracepoints_mutex);
+static DEFINE_MUTEX(tracepoint_module_list_mutex);
 
-#ifdef CONFIG_MODULES
-/* Local list of struct module */
+/* Local list of struct tp_module */
 static LIST_HEAD(tracepoint_module_list);
 #endif /* CONFIG_MODULES */
 
 /*
- * Tracepoint hash table, containing the active tracepoints.
- * Protected by tracepoints_mutex.
+ * tracepoints_mutex protects the builtin and module tracepoints.
+ * tracepoints_mutex nests inside tracepoint_module_list_mutex.
  */
-#define TRACEPOINT_HASH_BITS 6
-#define TRACEPOINT_TABLE_SIZE (1 << TRACEPOINT_HASH_BITS)
-static struct hlist_head tracepoint_table[TRACEPOINT_TABLE_SIZE];
+static DEFINE_MUTEX(tracepoints_mutex);
 
 /*
  * Note about RCU :
  * It is used to delay the free of multiple probes array until a quiescent
  * state is reached.
- * Tracepoint entries modifications are protected by the tracepoints_mutex.
  */
-struct tracepoint_entry {
-	struct hlist_node hlist;
-	struct tracepoint_func *funcs;
-	int refcount;	/* Number of times armed. 0 if disarmed. */
-	char name[0];
-};
-
 struct tp_probes {
-	union {
-		struct rcu_head rcu;
-		struct list_head list;
-	} u;
+	struct rcu_head rcu;
 	struct tracepoint_func probes[0];
 };
 
@@ -82,7 +68,7 @@ static inline void *allocate_probes(int count)
 
 static void rcu_free_old_probes(struct rcu_head *head)
 {
-	kfree(container_of(head, struct tp_probes, u.rcu));
+	kfree(container_of(head, struct tp_probes, rcu));
 }
 
 static inline void release_probes(struct tracepoint_func *old)
@@ -90,38 +76,37 @@ static inline void release_probes(struct tracepoint_func *old)
 	if (old) {
 		struct tp_probes *tp_probes = container_of(old,
 			struct tp_probes, probes[0]);
-		call_rcu_sched(&tp_probes->u.rcu, rcu_free_old_probes);
+		call_rcu_sched(&tp_probes->rcu, rcu_free_old_probes);
 	}
 }
 
-static void debug_print_probes(struct tracepoint_entry *entry)
+static void debug_print_probes(struct tracepoint_func *funcs)
 {
 	int i;
 
-	if (!tracepoint_debug || !entry->funcs)
+	if (!tracepoint_debug || !funcs)
 		return;
 
-	for (i = 0; entry->funcs[i].func; i++)
-		printk(KERN_DEBUG "Probe %d : %p\n", i, entry->funcs[i].func);
+	for (i = 0; funcs[i].func; i++)
+		printk(KERN_DEBUG "Probe %d : %p\n", i, funcs[i].func);
 }
 
-static struct tracepoint_func *
-tracepoint_entry_add_probe(struct tracepoint_entry *entry,
-			   void *probe, void *data)
+static struct tracepoint_func *func_add(struct tracepoint_func **funcs,
+		struct tracepoint_func *tp_func)
 {
 	int nr_probes = 0;
 	struct tracepoint_func *old, *new;
 
-	if (WARN_ON(!probe))
+	if (WARN_ON(!tp_func->func))
 		return ERR_PTR(-EINVAL);
 
-	debug_print_probes(entry);
-	old = entry->funcs;
+	debug_print_probes(*funcs);
+	old = *funcs;
 	if (old) {
 		/* (N -> N+1), (N != 0, 1) probes */
 		for (nr_probes = 0; old[nr_probes].func; nr_probes++)
-			if (old[nr_probes].func == probe &&
-			    old[nr_probes].data == data)
+			if (old[nr_probes].func == tp_func->func &&
+			    old[nr_probes].data == tp_func->data)
 				return ERR_PTR(-EEXIST);
 	}
 	/* + 2 : one for new probe, one for NULL func */
@@ -130,33 +115,30 @@ tracepoint_entry_add_probe(struct tracepoint_entry *entry,
 		return ERR_PTR(-ENOMEM);
 	if (old)
 		memcpy(new, old, nr_probes * sizeof(struct tracepoint_func));
-	new[nr_probes].func = probe;
-	new[nr_probes].data = data;
+	new[nr_probes] = *tp_func;
 	new[nr_probes + 1].func = NULL;
-	entry->refcount = nr_probes + 1;
-	entry->funcs = new;
-	debug_print_probes(entry);
+	*funcs = new;
+	debug_print_probes(*funcs);
 	return old;
 }
 
-static void *
-tracepoint_entry_remove_probe(struct tracepoint_entry *entry,
-			      void *probe, void *data)
+static void *func_remove(struct tracepoint_func **funcs,
+		struct tracepoint_func *tp_func)
 {
 	int nr_probes = 0, nr_del = 0, i;
 	struct tracepoint_func *old, *new;
 
-	old = entry->funcs;
+	old = *funcs;
 
 	if (!old)
 		return ERR_PTR(-ENOENT);
 
-	debug_print_probes(entry);
+	debug_print_probes(*funcs);
 	/* (N -> M), (N > 1, M >= 0) probes */
-	if (probe) {
+	if (tp_func->func) {
 		for (nr_probes = 0; old[nr_probes].func; nr_probes++) {
-			if (old[nr_probes].func == probe &&
-			     old[nr_probes].data == data)
+			if (old[nr_probes].func == tp_func->func &&
+			     old[nr_probes].data == tp_func->data)
 				nr_del++;
 		}
 	}
@@ -167,9 +149,8 @@ tracepoint_entry_remove_probe(struct tracepoint_entry *entry,
 	 */
 	if (nr_probes - nr_del == 0) {
 		/* N -> 0, (N > 1) */
-		entry->funcs = NULL;
-		entry->refcount = 0;
-		debug_print_probes(entry);
+		*funcs = NULL;
+		debug_print_probes(*funcs);
 		return old;
 	} else {
 		int j = 0;
@@ -179,90 +160,34 @@ tracepoint_entry_remove_probe(struct tracepoint_entry *entry,
 		if (new == NULL)
 			return ERR_PTR(-ENOMEM);
 		for (i = 0; old[i].func; i++)
-			if (old[i].func != probe || old[i].data != data)
+			if (old[i].func != tp_func->func
+					|| old[i].data != tp_func->data)
 				new[j++] = old[i];
 		new[nr_probes - nr_del].func = NULL;
-		entry->refcount = nr_probes - nr_del;
-		entry->funcs = new;
+		*funcs = new;
 	}
-	debug_print_probes(entry);
+	debug_print_probes(*funcs);
 	return old;
 }
 
 /*
- * Get tracepoint if the tracepoint is present in the tracepoint hash table.
- * Must be called with tracepoints_mutex held.
- * Returns NULL if not present.
+ * Add the probe function to a tracepoint.
  */
-static struct tracepoint_entry *get_tracepoint(const char *name)
+static int tracepoint_add_func(struct tracepoint *tp,
+		struct tracepoint_func *func)
 {
-	struct hlist_head *head;
-	struct tracepoint_entry *e;
-	u32 hash = jhash(name, strlen(name), 0);
-
-	head = &tracepoint_table[hash & (TRACEPOINT_TABLE_SIZE - 1)];
-	hlist_for_each_entry(e, head, hlist) {
-		if (!strcmp(name, e->name))
-			return e;
-	}
-	return NULL;
-}
+	struct tracepoint_func *old, *tp_funcs;
 
-/*
- * Add the tracepoint to the tracepoint hash table. Must be called with
- * tracepoints_mutex held.
- */
-static struct tracepoint_entry *add_tracepoint(const char *name)
-{
-	struct hlist_head *head;
-	struct tracepoint_entry *e;
-	size_t name_len = strlen(name) + 1;
-	u32 hash = jhash(name, name_len-1, 0);
-
-	head = &tracepoint_table[hash & (TRACEPOINT_TABLE_SIZE - 1)];
-	hlist_for_each_entry(e, head, hlist) {
-		if (!strcmp(name, e->name)) {
-			printk(KERN_NOTICE
-				"tracepoint %s busy\n", name);
-			return ERR_PTR(-EEXIST);	/* Already there */
-		}
-	}
-	/*
-	 * Using kmalloc here to allocate a variable length element. Could
-	 * cause some memory fragmentation if overused.
-	 */
-	e = kmalloc(sizeof(struct tracepoint_entry) + name_len, GFP_KERNEL);
-	if (!e)
-		return ERR_PTR(-ENOMEM);
-	memcpy(&e->name[0], name, name_len);
-	e->funcs = NULL;
-	e->refcount = 0;
-	hlist_add_head(&e->hlist, head);
-	return e;
-}
-
-/*
- * Remove the tracepoint from the tracepoint hash table. Must be called with
- * mutex_lock held.
- */
-static inline void remove_tracepoint(struct tracepoint_entry *e)
-{
-	hlist_del(&e->hlist);
-	kfree(e);
-}
-
-/*
- * Sets the probe callback corresponding to one tracepoint.
- */
-static void set_tracepoint(struct tracepoint_entry **entry,
-	struct tracepoint *elem, int active)
-{
-	WARN_ON(strcmp((*entry)->name, elem->name) != 0);
+	if (tp->regfunc && !static_key_enabled(&tp->key))
+		tp->regfunc();
 
-	if (elem->regfunc && !static_key_enabled(&elem->key) && active)
-		elem->regfunc();
-	else if (elem->unregfunc && static_key_enabled(&elem->key) && !active)
-		elem->unregfunc();
+	tp_funcs = rcu_dereference_protected(tp->funcs,
+			lockdep_is_held(&tracepoints_mutex));
+	old = func_add(&tp_funcs, func);
+	if (IS_ERR(old)) {
+		WARN_ON_ONCE(1);
+		return PTR_ERR(old);
+	}
 
 	/*
 	 * rcu_assign_pointer has a smp_wmb() which makes sure that the new
@@ -271,426 +196,216 @@ static void set_tracepoint(struct tracepoint_entry **entry,
 	 * include/linux/tracepoints.h. A matching smp_read_barrier_depends()
 	 * is used.
 	 */
-	rcu_assign_pointer(elem->funcs, (*entry)->funcs);
-	if (active && !static_key_enabled(&elem->key))
-		static_key_slow_inc(&elem->key);
-	else if (!active && static_key_enabled(&elem->key))
-		static_key_slow_dec(&elem->key);
+	rcu_assign_pointer(tp->funcs, tp_funcs);
+	if (!static_key_enabled(&tp->key))
+		static_key_slow_inc(&tp->key);
+	release_probes(old);
+	return 0;
 }
 
 /*
- * Disable a tracepoint and its probe callback.
+ * Remove a probe function from a tracepoint.
  * Note: only waiting an RCU period after setting elem->call to the empty
  * function insures that the original callback is not used anymore. This insured
  * by preempt_disable around the call site.
  */
-static void disable_tracepoint(struct tracepoint *elem)
+static int tracepoint_remove_func(struct tracepoint *tp,
+		struct tracepoint_func *func)
 {
-	if (elem->unregfunc && static_key_enabled(&elem->key))
-		elem->unregfunc();
+	struct tracepoint_func *old, *tp_funcs;
 
-	if (static_key_enabled(&elem->key))
-		static_key_slow_dec(&elem->key);
-	rcu_assign_pointer(elem->funcs, NULL);
-}
-
-/**
- * tracepoint_update_probe_range - Update a probe range
- * @begin: beginning of the range
- * @end: end of the range
- *
- * Updates the probe callback corresponding to a range of tracepoints.
- * Called with tracepoints_mutex held.
- */
-static void tracepoint_update_probe_range(struct tracepoint * const *begin,
-					  struct tracepoint * const *end)
-{
-	struct tracepoint * const *iter;
-	struct tracepoint_entry *mark_entry;
-
-	if (!begin)
-		return;
-
-	for (iter = begin; iter < end; iter++) {
-		mark_entry = get_tracepoint((*iter)->name);
-		if (mark_entry) {
-			set_tracepoint(&mark_entry, *iter,
-					!!mark_entry->refcount);
-		} else {
-			disable_tracepoint(*iter);
-		}
+	tp_funcs = rcu_dereference_protected(tp->funcs,
+			lockdep_is_held(&tracepoints_mutex));
+	old = func_remove(&tp_funcs, func);
+	if (IS_ERR(old)) {
+		WARN_ON_ONCE(1);
+		return PTR_ERR(old);
 	}
-}
-
-#ifdef CONFIG_MODULES
-void module_update_tracepoints(void)
-{
-	struct tp_module *tp_mod;
-
-	list_for_each_entry(tp_mod, &tracepoint_module_list, list)
-		tracepoint_update_probe_range(tp_mod->tracepoints_ptrs,
-			tp_mod->tracepoints_ptrs + tp_mod->num_tracepoints);
-}
-#else /* CONFIG_MODULES */
-void module_update_tracepoints(void)
-{
-}
-#endif /* CONFIG_MODULES */
 
+	if (!tp_funcs) {
+		/* Removed last function */
+		if (tp->unregfunc && static_key_enabled(&tp->key))
+			tp->unregfunc();
 
-/*
- * Update probes, removing the faulty probes.
- * Called with tracepoints_mutex held.
- */
-static void tracepoint_update_probes(void)
-{
-	/* Core kernel tracepoints */
-	tracepoint_update_probe_range(__start___tracepoints_ptrs,
-		__stop___tracepoints_ptrs);
-	/* tracepoints in modules. */
-	module_update_tracepoints();
-}
-
-static struct tracepoint_func *
-tracepoint_add_probe(const char *name, void *probe, void *data)
-{
-	struct tracepoint_entry *entry;
-	struct tracepoint_func *old;
-
-	entry = get_tracepoint(name);
-	if (!entry) {
-		entry = add_tracepoint(name);
-		if (IS_ERR(entry))
-			return (struct tracepoint_func *)entry;
+		if (static_key_enabled(&tp->key))
+			static_key_slow_dec(&tp->key);
 	}
-	old = tracepoint_entry_add_probe(entry, probe, data);
-	if (IS_ERR(old) && !entry->refcount)
-		remove_tracepoint(entry);
-	return old;
+	rcu_assign_pointer(tp->funcs, tp_funcs);
+	release_probes(old);
+	return 0;
 }
 
 /**
  * tracepoint_probe_register -  Connect a probe to a tracepoint
- * @name: tracepoint name
+ * @tp: tracepoint
  * @probe: probe handler
  *
  * Returns 0 if ok, error value on error.
- * The probe address must at least be aligned on the architecture pointer size.
+ * Note: if @tp is within a module, the caller is responsible for
+ * unregistering the probe before the module is gone. This can be
+ * performed either with a tracepoint module going notifier, or from
+ * within module exit functions.
  */
-int tracepoint_probe_register(const char *name, void *probe, void *data)
+int tracepoint_probe_register(struct tracepoint *tp, void *probe, void *data)
 {
-	struct tracepoint_func *old;
+	struct tracepoint_func tp_func;
+	int ret;
 
 	mutex_lock(&tracepoints_mutex);
-	old = tracepoint_add_probe(name, probe, data);
-	if (IS_ERR(old)) {
-		mutex_unlock(&tracepoints_mutex);
-		return PTR_ERR(old);
-	}
-	tracepoint_update_probes();		/* may update entry */
+	tp_func.func = probe;
+	tp_func.data = data;
+	ret = tracepoint_add_func(tp, &tp_func);
 	mutex_unlock(&tracepoints_mutex);
-	release_probes(old);
-	return 0;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(tracepoint_probe_register);
 
-static struct tracepoint_func *
-tracepoint_remove_probe(const char *name, void *probe, void *data)
-{
-	struct tracepoint_entry *entry;
-	struct tracepoint_func *old;
-
-	entry = get_tracepoint(name);
-	if (!entry)
-		return ERR_PTR(-ENOENT);
-	old = tracepoint_entry_remove_probe(entry, probe, data);
-	if (IS_ERR(old))
-		return old;
-	if (!entry->refcount)
-		remove_tracepoint(entry);
-	return old;
-}
-
 /**
  * tracepoint_probe_unregister -  Disconnect a probe from a tracepoint
- * @name: tracepoint name
+ * @tp: tracepoint
  * @probe: probe function pointer
  *
- * We do not need to call a synchronize_sched to make sure the probes have
- * finished running before doing a module unload, because the module unload
- * itself uses stop_machine(), which insures that every preempt disabled section
- * have finished.
+ * Returns 0 if ok, error value on error.
  */
-int tracepoint_probe_unregister(const char *name, void *probe, void *data)
+int tracepoint_probe_unregister(struct tracepoint *tp, void *probe, void *data)
 {
-	struct tracepoint_func *old;
+	struct tracepoint_func tp_func;
+	int ret;
 
 	mutex_lock(&tracepoints_mutex);
-	old = tracepoint_remove_probe(name, probe, data);
-	if (IS_ERR(old)) {
-		mutex_unlock(&tracepoints_mutex);
-		return PTR_ERR(old);
-	}
-	tracepoint_update_probes();		/* may update entry */
+	tp_func.func = probe;
+	tp_func.data = data;
+	ret = tracepoint_remove_func(tp, &tp_func);
 	mutex_unlock(&tracepoints_mutex);
-	release_probes(old);
-	return 0;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(tracepoint_probe_unregister);
 
-static LIST_HEAD(old_probes);
-static int need_update;
-
-static void tracepoint_add_old_probes(void *old)
+#ifdef CONFIG_MODULES
+bool trace_module_has_bad_taint(struct module *mod)
 {
-	need_update = 1;
-	if (old) {
-		struct tp_probes *tp_probes = container_of(old,
-			struct tp_probes, probes[0]);
-		list_add(&tp_probes->u.list, &old_probes);
-	}
+	return mod->taints & ~((1 << TAINT_OOT_MODULE) | (1 << TAINT_CRAP) |
+			       (1 << TAINT_UNSIGNED_MODULE));
 }
 
-/**
- * tracepoint_probe_register_noupdate -  register a probe but not connect
- * @name: tracepoint name
- * @probe: probe handler
- *
- * caller must call tracepoint_probe_update_all()
- */
-int tracepoint_probe_register_noupdate(const char *name, void *probe,
-				       void *data)
-{
-	struct tracepoint_func *old;
-
-	mutex_lock(&tracepoints_mutex);
-	old = tracepoint_add_probe(name, probe, data);
-	if (IS_ERR(old)) {
-		mutex_unlock(&tracepoints_mutex);
-		return PTR_ERR(old);
-	}
-	tracepoint_add_old_probes(old);
-	mutex_unlock(&tracepoints_mutex);
-	return 0;
-}
-EXPORT_SYMBOL_GPL(tracepoint_probe_register_noupdate);
+static BLOCKING_NOTIFIER_HEAD(tracepoint_notify_list);
 
 /**
- * tracepoint_probe_unregister_noupdate -  remove a probe but not disconnect
- * @name: tracepoint name
- * @probe: probe function pointer
+ * register_tracepoint_notifier - register tracepoint coming/going notifier
+ * @nb: notifier block
  *
- * caller must call tracepoint_probe_update_all()
+ * Notifiers registered with this function are called on module
+ * coming/going with the tracepoint_module_list_mutex held.
+ * The notifier block callback should expect a "struct tp_module" data
+ * pointer.
  */
-int tracepoint_probe_unregister_noupdate(const char *name, void *probe,
-					 void *data)
+int register_tracepoint_module_notifier(struct notifier_block *nb)
 {
-	struct tracepoint_func *old;
-
-	mutex_lock(&tracepoints_mutex);
-	old = tracepoint_remove_probe(name, probe, data);
-	if (IS_ERR(old)) {
-		mutex_unlock(&tracepoints_mutex);
-		return PTR_ERR(old);
-	}
-	tracepoint_add_old_probes(old);
-	mutex_unlock(&tracepoints_mutex);
-	return 0;
-}
-EXPORT_SYMBOL_GPL(tracepoint_probe_unregister_noupdate);
-
-/**
- * tracepoint_probe_update_all -  update tracepoints
- */
-void tracepoint_probe_update_all(void)
-{
-	LIST_HEAD(release_probes);
-	struct tp_probes *pos, *next;
+	struct tp_module *tp_mod;
+	int ret;
 
-	mutex_lock(&tracepoints_mutex);
-	if (!need_update) {
-		mutex_unlock(&tracepoints_mutex);
-		return;
-	}
-	if (!list_empty(&old_probes))
-		list_replace_init(&old_probes, &release_probes);
-	need_update = 0;
-	tracepoint_update_probes();
-	mutex_unlock(&tracepoints_mutex);
-	list_for_each_entry_safe(pos, next, &release_probes, u.list) {
-		list_del(&pos->u.list);
-		call_rcu_sched(&pos->u.rcu, rcu_free_old_probes);
-	}
+	mutex_lock(&tracepoint_module_list_mutex);
+	ret = blocking_notifier_chain_register(&tracepoint_notify_list, nb);
+	if (ret)
+		goto end;
+	list_for_each_entry(tp_mod, &tracepoint_module_list, list)
+		(void) nb->notifier_call(nb, MODULE_STATE_COMING, tp_mod);
+end:
+	mutex_unlock(&tracepoint_module_list_mutex);
+	return ret;
 }
-EXPORT_SYMBOL_GPL(tracepoint_probe_update_all);
+EXPORT_SYMBOL_GPL(register_tracepoint_module_notifier);
 
 /**
- * tracepoint_get_iter_range - Get a next tracepoint iterator given a range.
- * @tracepoint: current tracepoints (in), next tracepoint (out)
- * @begin: beginning of the range
- * @end: end of the range
+ * unregister_tracepoint_notifier - unregister tracepoint coming/going notifier
+ * @nb: notifier block
  *
- * Returns whether a next tracepoint has been found (1) or not (0).
- * Will return the first tracepoint in the range if the input tracepoint is
- * NULL.
+ * The notifier block callback should expect a "struct tp_module" data
+ * pointer.
  */
-static int tracepoint_get_iter_range(struct tracepoint * const **tracepoint,
-	struct tracepoint * const *begin, struct tracepoint * const *end)
+int unregister_tracepoint_module_notifier(struct notifier_block *nb)
 {
-	if (!*tracepoint && begin != end) {
-		*tracepoint = begin;
-		return 1;
-	}
-	if (*tracepoint >= begin && *tracepoint < end)
-		return 1;
-	return 0;
-}
+	struct tp_module *tp_mod;
+	int ret;
 
-#ifdef CONFIG_MODULES
-static void tracepoint_get_iter(struct tracepoint_iter *iter)
-{
-	int found = 0;
-	struct tp_module *iter_mod;
-
-	/* Core kernel tracepoints */
-	if (!iter->module) {
-		found = tracepoint_get_iter_range(&iter->tracepoint,
-				__start___tracepoints_ptrs,
-				__stop___tracepoints_ptrs);
-		if (found)
-			goto end;
-	}
-	/* Tracepoints in modules */
-	mutex_lock(&tracepoints_mutex);
-	list_for_each_entry(iter_mod, &tracepoint_module_list, list) {
-		/*
-		 * Sorted module list
-		 */
-		if (iter_mod < iter->module)
-			continue;
-		else if (iter_mod > iter->module)
-			iter->tracepoint = NULL;
-		found = tracepoint_get_iter_range(&iter->tracepoint,
-			iter_mod->tracepoints_ptrs,
-			iter_mod->tracepoints_ptrs
-				+ iter_mod->num_tracepoints);
-		if (found) {
-			iter->module = iter_mod;
-			break;
-		}
-	}
-	mutex_unlock(&tracepoints_mutex);
+	mutex_lock(&tracepoint_module_list_mutex);
+	ret = blocking_notifier_chain_unregister(&tracepoint_notify_list, nb);
+	if (ret)
+		goto end;
+	list_for_each_entry(tp_mod, &tracepoint_module_list, list)
+		(void) nb->notifier_call(nb, MODULE_STATE_GOING, tp_mod);
 end:
-	if (!found)
-		tracepoint_iter_reset(iter);
-}
-#else /* CONFIG_MODULES */
-static void tracepoint_get_iter(struct tracepoint_iter *iter)
-{
-	int found = 0;
-
-	/* Core kernel tracepoints */
-	found = tracepoint_get_iter_range(&iter->tracepoint,
-			__start___tracepoints_ptrs,
-			__stop___tracepoints_ptrs);
-	if (!found)
-		tracepoint_iter_reset(iter);
-}
-#endif /* CONFIG_MODULES */
-
-void tracepoint_iter_start(struct tracepoint_iter *iter)
-{
-	tracepoint_get_iter(iter);
-}
-EXPORT_SYMBOL_GPL(tracepoint_iter_start);
-
-void tracepoint_iter_next(struct tracepoint_iter *iter)
-{
-	iter->tracepoint++;
-	/*
-	 * iter->tracepoint may be invalid because we blindly incremented it.
-	 * Make sure it is valid by marshalling on the tracepoints, getting the
-	 * tracepoints from following modules if necessary.
-	 */
-	tracepoint_get_iter(iter);
-}
-EXPORT_SYMBOL_GPL(tracepoint_iter_next);
+	mutex_unlock(&tracepoint_module_list_mutex);
+	return ret;
 
-void tracepoint_iter_stop(struct tracepoint_iter *iter)
-{
 }
-EXPORT_SYMBOL_GPL(tracepoint_iter_stop);
+EXPORT_SYMBOL_GPL(unregister_tracepoint_module_notifier);
 
-void tracepoint_iter_reset(struct tracepoint_iter *iter)
+/*
+ * Ensure the tracer unregistered the module's probes before the module
+ * teardown is performed. Prevents leaks of probe and data pointers.
+ */
+static void tp_module_going_check_quiescent(struct tracepoint * const *begin,
+		struct tracepoint * const *end)
 {
-#ifdef CONFIG_MODULES
-	iter->module = NULL;
-#endif /* CONFIG_MODULES */
-	iter->tracepoint = NULL;
-}
-EXPORT_SYMBOL_GPL(tracepoint_iter_reset);
+	struct tracepoint * const *iter;
 
-#ifdef CONFIG_MODULES
-bool trace_module_has_bad_taint(struct module *mod)
-{
-	return mod->taints & ~((1 << TAINT_OOT_MODULE) | (1 << TAINT_CRAP));
+	if (!begin)
+		return;
+	for (iter = begin; iter < end; iter++)
+		WARN_ON_ONCE((*iter)->funcs);
 }
 
 static int tracepoint_module_coming(struct module *mod)
 {
-	struct tp_module *tp_mod, *iter;
+	struct tp_module *tp_mod;
 	int ret = 0;
 
+	if (!mod->num_tracepoints)
+		return 0;
+
 	/*
 	 * We skip modules that taint the kernel, especially those with different
 	 * module headers (for forced load), to make sure we don't cause a crash.
-	 * Staging and out-of-tree GPL modules are fine.
+	 * Staging, out-of-tree, and unsigned GPL modules are fine.
 	 */
 	if (trace_module_has_bad_taint(mod))
 		return 0;
-	mutex_lock(&tracepoints_mutex);
+	mutex_lock(&tracepoint_module_list_mutex);
 	tp_mod = kmalloc(sizeof(struct tp_module), GFP_KERNEL);
 	if (!tp_mod) {
 		ret = -ENOMEM;
 		goto end;
 	}
-	tp_mod->num_tracepoints = mod->num_tracepoints;
-	tp_mod->tracepoints_ptrs = mod->tracepoints_ptrs;
-
-	/*
-	 * tracepoint_module_list is kept sorted by struct module pointer
-	 * address for iteration on tracepoints from a seq_file that can release
-	 * the mutex between calls.
-	 */
-	list_for_each_entry_reverse(iter, &tracepoint_module_list, list) {
-		BUG_ON(iter == tp_mod);	/* Should never be in the list twice */
-		if (iter < tp_mod) {
-			/* We belong to the location right after iter. */
-			list_add(&tp_mod->list, &iter->list);
-			goto module_added;
-		}
-	}
-	/* We belong to the beginning of the list */
-	list_add(&tp_mod->list, &tracepoint_module_list);
-module_added:
-	tracepoint_update_probe_range(mod->tracepoints_ptrs,
-		mod->tracepoints_ptrs + mod->num_tracepoints);
+	tp_mod->mod = mod;
+	list_add_tail(&tp_mod->list, &tracepoint_module_list);
+	blocking_notifier_call_chain(&tracepoint_notify_list,
+			MODULE_STATE_COMING, tp_mod);
 end:
-	mutex_unlock(&tracepoints_mutex);
+	mutex_unlock(&tracepoint_module_list_mutex);
 	return ret;
 }
 
-static int tracepoint_module_going(struct module *mod)
+static void tracepoint_module_going(struct module *mod)
 {
-	struct tp_module *pos;
+	struct tp_module *tp_mod;
 
-	mutex_lock(&tracepoints_mutex);
-	tracepoint_update_probe_range(mod->tracepoints_ptrs,
-		mod->tracepoints_ptrs + mod->num_tracepoints);
-	list_for_each_entry(pos, &tracepoint_module_list, list) {
-		if (pos->tracepoints_ptrs == mod->tracepoints_ptrs) {
-			list_del(&pos->list);
-			kfree(pos);
+	if (!mod->num_tracepoints)
+		return;
+
+	mutex_lock(&tracepoint_module_list_mutex);
+	list_for_each_entry(tp_mod, &tracepoint_module_list, list) {
+		if (tp_mod->mod == mod) {
+			blocking_notifier_call_chain(&tracepoint_notify_list,
+					MODULE_STATE_GOING, tp_mod);
+			list_del(&tp_mod->list);
+			kfree(tp_mod);
+			/*
+			 * Called the going notifier before checking for
+			 * quiescence.
+			 */
+			tp_module_going_check_quiescent(mod->tracepoints_ptrs,
+				mod->tracepoints_ptrs + mod->num_tracepoints);
 			break;
 		}
 	}
@@ -700,12 +415,11 @@ static int tracepoint_module_going(struct module *mod)
 	 * flag on "going", in case a module taints the kernel only after being
 	 * loaded.
 	 */
-	mutex_unlock(&tracepoints_mutex);
-	return 0;
+	mutex_unlock(&tracepoint_module_list_mutex);
 }
 
-int tracepoint_module_notify(struct notifier_block *self,
-			     unsigned long val, void *data)
+static int tracepoint_module_notify(struct notifier_block *self,
+		unsigned long val, void *data)
 {
 	struct module *mod = data;
 	int ret = 0;
@@ -717,24 +431,58 @@ int tracepoint_module_notify(struct notifier_block *self,
 	case MODULE_STATE_LIVE:
 		break;
 	case MODULE_STATE_GOING:
-		ret = tracepoint_module_going(mod);
+		tracepoint_module_going(mod);
+		break;
+	case MODULE_STATE_UNFORMED:
 		break;
 	}
 	return ret;
 }
 
-struct notifier_block tracepoint_module_nb = {
+static struct notifier_block tracepoint_module_nb = {
 	.notifier_call = tracepoint_module_notify,
 	.priority = 0,
 };
 
-static int init_tracepoints(void)
+static __init int init_tracepoints(void)
 {
-	return register_module_notifier(&tracepoint_module_nb);
+	int ret;
+
+	ret = register_module_notifier(&tracepoint_module_nb);
+	if (ret)
+		pr_warning("Failed to register tracepoint module enter notifier\n");
+
+	return ret;
 }
 __initcall(init_tracepoints);
 #endif /* CONFIG_MODULES */
 
+static void for_each_tracepoint_range(struct tracepoint * const *begin,
+		struct tracepoint * const *end,
+		void (*fct)(struct tracepoint *tp, void *priv),
+		void *priv)
+{
+	struct tracepoint * const *iter;
+
+	if (!begin)
+		return;
+	for (iter = begin; iter < end; iter++)
+		fct(*iter, priv);
+}
+
+/**
+ * for_each_kernel_tracepoint - iteration on all kernel tracepoints
+ * @fct: callback
+ * @priv: private data
+ */
+void for_each_kernel_tracepoint(void (*fct)(struct tracepoint *tp, void *priv),
+		void *priv)
+{
+	for_each_tracepoint_range(__start___tracepoints_ptrs,
+		__stop___tracepoints_ptrs, fct, priv);
+}
+EXPORT_SYMBOL_GPL(for_each_kernel_tracepoint);
+
 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
 
 /* NB: reg/unreg are called while guarded with the tracepoints_mutex */
diff --git a/kernel/up.c b/kernel/up.c
index 509403e3fbc6..1760bf3d1463 100644
--- a/kernel/up.c
+++ b/kernel/up.c
@@ -22,16 +22,16 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
 }
 EXPORT_SYMBOL(smp_call_function_single);
 
-void __smp_call_function_single(int cpu, struct call_single_data *csd,
-				int wait)
+int smp_call_function_single_async(int cpu, struct call_single_data *csd)
 {
 	unsigned long flags;
 
 	local_irq_save(flags);
 	csd->func(csd->info);
 	local_irq_restore(flags);
+	return 0;
 }
-EXPORT_SYMBOL(__smp_call_function_single);
+EXPORT_SYMBOL(smp_call_function_single_async);
 
 int on_each_cpu(smp_call_func_t func, void *info, int wait)
 {
diff --git a/kernel/user.c b/kernel/user.c
index c006131beb77..294fc6a94168 100644
--- a/kernel/user.c
+++ b/kernel/user.c
@@ -222,5 +222,4 @@ static int __init uid_cache_init(void)
 
 	return 0;
 }
-
-module_init(uid_cache_init);
+subsys_initcall(uid_cache_init);
diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index dd06439b9c84..bf71b4b2d632 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -152,7 +152,7 @@ static u32 map_id_range_down(struct uid_gid_map *map, u32 id, u32 count)
 
 	/* Find the matching extent */
 	extents = map->nr_extents;
-	smp_read_barrier_depends();
+	smp_rmb();
 	for (idx = 0; idx < extents; idx++) {
 		first = map->extent[idx].first;
 		last = first + map->extent[idx].count - 1;
@@ -176,7 +176,7 @@ static u32 map_id_down(struct uid_gid_map *map, u32 id)
 
 	/* Find the matching extent */
 	extents = map->nr_extents;
-	smp_read_barrier_depends();
+	smp_rmb();
 	for (idx = 0; idx < extents; idx++) {
 		first = map->extent[idx].first;
 		last = first + map->extent[idx].count - 1;
@@ -199,7 +199,7 @@ static u32 map_id_up(struct uid_gid_map *map, u32 id)
 
 	/* Find the matching extent */
 	extents = map->nr_extents;
-	smp_read_barrier_depends();
+	smp_rmb();
 	for (idx = 0; idx < extents; idx++) {
 		first = map->extent[idx].lower_first;
 		last = first + map->extent[idx].count - 1;
@@ -615,9 +615,8 @@ static ssize_t map_write(struct file *file, const char __user *buf,
 	 * were written before the count of the extents.
 	 *
 	 * To achieve this smp_wmb() is used on guarantee the write
-	 * order and smp_read_barrier_depends() is guaranteed that we
-	 * don't have crazy architectures returning stale data.
-	 *
+	 * order and smp_rmb() is guaranteed that we don't have crazy
+	 * architectures returning stale data.
 	 */
 	mutex_lock(&id_map_mutex);
 
@@ -902,4 +901,4 @@ static __init int user_namespaces_init(void)
 	user_ns_cachep = KMEM_CACHE(user_namespace, SLAB_PANIC);
 	return 0;
 }
-module_init(user_namespaces_init);
+subsys_initcall(user_namespaces_init);
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 4431610f049a..516203e665fc 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -138,7 +138,11 @@ static void __touch_watchdog(void)
 
 void touch_softlockup_watchdog(void)
 {
-	__this_cpu_write(watchdog_touch_ts, 0);
+	/*
+	 * Preemption can be enabled.  It doesn't matter which CPU's timestamp
+	 * gets zeroed here, so use the raw_ operation.
+	 */
+	raw_cpu_write(watchdog_touch_ts, 0);
 }
 EXPORT_SYMBOL(touch_softlockup_watchdog);
 
@@ -158,14 +162,14 @@ void touch_all_softlockup_watchdogs(void)
 #ifdef CONFIG_HARDLOCKUP_DETECTOR
 void touch_nmi_watchdog(void)
 {
-	if (watchdog_user_enabled) {
-		unsigned cpu;
-
-		for_each_present_cpu(cpu) {
-			if (per_cpu(watchdog_nmi_touch, cpu) != true)
-				per_cpu(watchdog_nmi_touch, cpu) = true;
-		}
-	}
+	/*
+	 * Using __raw here because some code paths have
+	 * preemption enabled.  If preemption is enabled
+	 * then interrupts should be enabled too, in which
+	 * case we shouldn't have to worry about the watchdog
+	 * going off.
+	 */
+	__raw_get_cpu_var(watchdog_nmi_touch) = true;
 	touch_softlockup_watchdog();
 }
 EXPORT_SYMBOL(touch_nmi_watchdog);
@@ -505,7 +509,6 @@ static void restart_watchdog_hrtimer(void *info)
 
 static void update_timers(int cpu)
 {
-	struct call_single_data data = {.func = restart_watchdog_hrtimer};
 	/*
 	 * Make sure that perf event counter will adopt to a new
 	 * sampling period. Updating the sampling period directly would
@@ -515,7 +518,7 @@ static void update_timers(int cpu)
 	 * might be late already so we have to restart the timer as well.
 	 */
 	watchdog_nmi_disable(cpu);
-	__smp_call_function_single(cpu, &data, 1);
+	smp_call_function_single(cpu, restart_watchdog_hrtimer, NULL, 1);
 	watchdog_nmi_enable(cpu);
 }
 
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 193e977a10ea..8edc87185427 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -516,6 +516,13 @@ void destroy_work_on_stack(struct work_struct *work)
 }
 EXPORT_SYMBOL_GPL(destroy_work_on_stack);
 
+void destroy_delayed_work_on_stack(struct delayed_work *work)
+{
+	destroy_timer_on_stack(&work->timer);
+	debug_object_free(&work->work, &work_debug_descr);
+}
+EXPORT_SYMBOL_GPL(destroy_delayed_work_on_stack);
+
 #else
 static inline void debug_work_activate(struct work_struct *work) { }
 static inline void debug_work_deactivate(struct work_struct *work) { }
@@ -1909,6 +1916,12 @@ static void send_mayday(struct work_struct *work)
 
 	/* mayday mayday mayday */
 	if (list_empty(&pwq->mayday_node)) {
+		/*
+		 * If @pwq is for an unbound wq, its base ref may be put at
+		 * any time due to an attribute change.  Pin @pwq until the
+		 * rescuer is done with it.
+		 */
+		get_pwq(pwq);
 		list_add_tail(&pwq->mayday_node, &wq->maydays);
 		wake_up_process(wq->rescuer->task);
 	}
@@ -2391,6 +2404,7 @@ static int rescuer_thread(void *__rescuer)
 	struct worker *rescuer = __rescuer;
 	struct workqueue_struct *wq = rescuer->rescue_wq;
 	struct list_head *scheduled = &rescuer->scheduled;
+	bool should_stop;
 
 	set_user_nice(current, RESCUER_NICE_LEVEL);
 
@@ -2402,11 +2416,15 @@ static int rescuer_thread(void *__rescuer)
 repeat:
 	set_current_state(TASK_INTERRUPTIBLE);
 
-	if (kthread_should_stop()) {
-		__set_current_state(TASK_RUNNING);
-		rescuer->task->flags &= ~PF_WQ_WORKER;
-		return 0;
-	}
+	/*
+	 * By the time the rescuer is requested to stop, the workqueue
+	 * shouldn't have any work pending, but @wq->maydays may still have
+	 * pwq(s) queued.  This can happen by non-rescuer workers consuming
+	 * all the work items before the rescuer got to them.  Go through
+	 * @wq->maydays processing before acting on should_stop so that the
+	 * list is always empty on exit.
+	 */
+	should_stop = kthread_should_stop();
 
 	/* see whether any pwq is asking for help */
 	spin_lock_irq(&wq_mayday_lock);
@@ -2438,6 +2456,12 @@ repeat:
 		process_scheduled_works(rescuer);
 
 		/*
+		 * Put the reference grabbed by send_mayday().  @pool won't
+		 * go away while we're holding its lock.
+		 */
+		put_pwq(pwq);
+
+		/*
 		 * Leave this pool.  If keep_working() is %true, notify a
 		 * regular worker; otherwise, we end up with 0 concurrency
 		 * and stalling the execution.
@@ -2452,6 +2476,12 @@ repeat:
 
 	spin_unlock_irq(&wq_mayday_lock);
 
+	if (should_stop) {
+		__set_current_state(TASK_RUNNING);
+		rescuer->task->flags &= ~PF_WQ_WORKER;
+		return 0;
+	}
+
 	/* rescuers should never participate in concurrency management */
 	WARN_ON_ONCE(!(rescuer->flags & WORKER_NOT_RUNNING));
 	schedule();
@@ -3225,7 +3255,7 @@ static ssize_t wq_nice_store(struct device *dev, struct device_attribute *attr,
 		return -ENOMEM;
 
 	if (sscanf(buf, "%d", &attrs->nice) == 1 &&
-	    attrs->nice >= -20 && attrs->nice <= 19)
+	    attrs->nice >= MIN_NICE && attrs->nice <= MAX_NICE)
 		ret = apply_workqueue_attrs(wq, attrs);
 	else
 		ret = -EINVAL;
@@ -4093,7 +4123,8 @@ static void wq_update_unbound_numa(struct workqueue_struct *wq, int cpu,
 	if (!pwq) {
 		pr_warning("workqueue: allocation failed while updating NUMA affinity of \"%s\"\n",
 			   wq->name);
-		goto out_unlock;
+		mutex_lock(&wq->mutex);
+		goto use_dfl_pwq;
 	}
 
 	/*