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-rw-r--r--kernel/Makefile7
-rw-r--r--kernel/cgroup.c30
-rw-r--r--kernel/cpu.c44
-rw-r--r--kernel/cpu_pm.c16
-rw-r--r--kernel/cred.c9
-rw-r--r--kernel/events/core.c11
-rw-r--r--kernel/exit.c32
-rw-r--r--kernel/fork.c11
-rw-r--r--kernel/irq/chip.c8
-rw-r--r--kernel/irq/internals.h3
-rw-r--r--kernel/irq/manage.c119
-rw-r--r--kernel/irq/migration.c13
-rw-r--r--kernel/kcmp.c196
-rw-r--r--kernel/kmod.c30
-rw-r--r--kernel/lglock.c89
-rw-r--r--kernel/panic.c6
-rw-r--r--kernel/pid_namespace.c33
-rw-r--r--kernel/printk.c241
-rw-r--r--kernel/rcutree.c2
-rw-r--r--kernel/rcutree.h14
-rw-r--r--kernel/rcutree_plugin.h165
-rw-r--r--kernel/resource.c4
-rw-r--r--kernel/sched/core.c249
-rw-r--r--kernel/sched/fair.c71
-rw-r--r--kernel/sched/rt.c53
-rw-r--r--kernel/sched/sched.h2
-rw-r--r--kernel/signal.c59
-rw-r--r--kernel/smpboot.c17
-rw-r--r--kernel/sys.c221
-rw-r--r--kernel/sys_ni.c3
-rw-r--r--kernel/task_work.c84
-rw-r--r--kernel/time/clockevents.c3
-rw-r--r--kernel/time/tick-sched.c26
-rw-r--r--kernel/time/timekeeping.c2
-rw-r--r--kernel/trace/trace.c2
-rw-r--r--kernel/watchdog.c19
36 files changed, 1459 insertions, 435 deletions
diff --git a/kernel/Makefile b/kernel/Makefile
index 6c07f30fa9b7..c0cc67ad764c 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -5,12 +5,12 @@
obj-y = fork.o exec_domain.o panic.o printk.o \
cpu.o exit.o itimer.o time.o softirq.o resource.o \
sysctl.o sysctl_binary.o capability.o ptrace.o timer.o user.o \
- signal.o sys.o kmod.o workqueue.o pid.o \
+ signal.o sys.o kmod.o workqueue.o pid.o task_work.o \
rcupdate.o extable.o params.o posix-timers.o \
kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \
hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
notifier.o ksysfs.o cred.o \
- async.o range.o groups.o
+ async.o range.o groups.o lglock.o
ifdef CONFIG_FUNCTION_TRACER
# Do not trace debug files and internal ftrace files
@@ -25,6 +25,9 @@ endif
obj-y += sched/
obj-y += power/
+ifeq ($(CONFIG_CHECKPOINT_RESTORE),y)
+obj-$(CONFIG_X86) += kcmp.o
+endif
obj-$(CONFIG_FREEZER) += freezer.o
obj-$(CONFIG_PROFILING) += profile.o
obj-$(CONFIG_STACKTRACE) += stacktrace.o
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 0f3527d6184a..2097684cf194 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -255,12 +255,17 @@ int cgroup_lock_is_held(void)
EXPORT_SYMBOL_GPL(cgroup_lock_is_held);
+static int css_unbias_refcnt(int refcnt)
+{
+ return refcnt >= 0 ? refcnt : refcnt - CSS_DEACT_BIAS;
+}
+
/* the current nr of refs, always >= 0 whether @css is deactivated or not */
static int css_refcnt(struct cgroup_subsys_state *css)
{
int v = atomic_read(&css->refcnt);
- return v >= 0 ? v : v - CSS_DEACT_BIAS;
+ return css_unbias_refcnt(v);
}
/* convenient tests for these bits */
@@ -896,10 +901,13 @@ static void cgroup_diput(struct dentry *dentry, struct inode *inode)
mutex_unlock(&cgroup_mutex);
/*
- * Drop the active superblock reference that we took when we
- * created the cgroup
+ * We want to drop the active superblock reference from the
+ * cgroup creation after all the dentry refs are gone -
+ * kill_sb gets mighty unhappy otherwise. Mark
+ * dentry->d_fsdata with cgroup_diput() to tell
+ * cgroup_d_release() to call deactivate_super().
*/
- deactivate_super(cgrp->root->sb);
+ dentry->d_fsdata = cgroup_diput;
/*
* if we're getting rid of the cgroup, refcount should ensure
@@ -925,6 +933,13 @@ static int cgroup_delete(const struct dentry *d)
return 1;
}
+static void cgroup_d_release(struct dentry *dentry)
+{
+ /* did cgroup_diput() tell me to deactivate super? */
+ if (dentry->d_fsdata == cgroup_diput)
+ deactivate_super(dentry->d_sb);
+}
+
static void remove_dir(struct dentry *d)
{
struct dentry *parent = dget(d->d_parent);
@@ -1532,6 +1547,7 @@ static int cgroup_get_rootdir(struct super_block *sb)
static const struct dentry_operations cgroup_dops = {
.d_iput = cgroup_diput,
.d_delete = cgroup_delete,
+ .d_release = cgroup_d_release,
};
struct inode *inode =
@@ -4971,10 +4987,12 @@ EXPORT_SYMBOL_GPL(__css_tryget);
void __css_put(struct cgroup_subsys_state *css)
{
struct cgroup *cgrp = css->cgroup;
+ int v;
rcu_read_lock();
- atomic_dec(&css->refcnt);
- switch (css_refcnt(css)) {
+ v = css_unbias_refcnt(atomic_dec_return(&css->refcnt));
+
+ switch (v) {
case 1:
if (notify_on_release(cgrp)) {
set_bit(CGRP_RELEASABLE, &cgrp->flags);
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 0e6353cf147a..a4eb5227a19e 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -10,7 +10,10 @@
#include <linux/sched.h>
#include <linux/unistd.h>
#include <linux/cpu.h>
+#include <linux/oom.h>
+#include <linux/rcupdate.h>
#include <linux/export.h>
+#include <linux/bug.h>
#include <linux/kthread.h>
#include <linux/stop_machine.h>
#include <linux/mutex.h>
@@ -173,6 +176,47 @@ void __ref unregister_cpu_notifier(struct notifier_block *nb)
}
EXPORT_SYMBOL(unregister_cpu_notifier);
+/**
+ * clear_tasks_mm_cpumask - Safely clear tasks' mm_cpumask for a CPU
+ * @cpu: a CPU id
+ *
+ * This function walks all processes, finds a valid mm struct for each one and
+ * then clears a corresponding bit in mm's cpumask. While this all sounds
+ * trivial, there are various non-obvious corner cases, which this function
+ * tries to solve in a safe manner.
+ *
+ * Also note that the function uses a somewhat relaxed locking scheme, so it may
+ * be called only for an already offlined CPU.
+ */
+void clear_tasks_mm_cpumask(int cpu)
+{
+ struct task_struct *p;
+
+ /*
+ * This function is called after the cpu is taken down and marked
+ * offline, so its not like new tasks will ever get this cpu set in
+ * their mm mask. -- Peter Zijlstra
+ * Thus, we may use rcu_read_lock() here, instead of grabbing
+ * full-fledged tasklist_lock.
+ */
+ WARN_ON(cpu_online(cpu));
+ rcu_read_lock();
+ for_each_process(p) {
+ struct task_struct *t;
+
+ /*
+ * Main thread might exit, but other threads may still have
+ * a valid mm. Find one.
+ */
+ t = find_lock_task_mm(p);
+ if (!t)
+ continue;
+ cpumask_clear_cpu(cpu, mm_cpumask(t->mm));
+ task_unlock(t);
+ }
+ rcu_read_unlock();
+}
+
static inline void check_for_tasks(int cpu)
{
struct task_struct *p;
diff --git a/kernel/cpu_pm.c b/kernel/cpu_pm.c
index 249152e15308..9656a3c36503 100644
--- a/kernel/cpu_pm.c
+++ b/kernel/cpu_pm.c
@@ -81,7 +81,7 @@ int cpu_pm_unregister_notifier(struct notifier_block *nb)
EXPORT_SYMBOL_GPL(cpu_pm_unregister_notifier);
/**
- * cpm_pm_enter - CPU low power entry notifier
+ * cpu_pm_enter - CPU low power entry notifier
*
* Notifies listeners that a single CPU is entering a low power state that may
* cause some blocks in the same power domain as the cpu to reset.
@@ -89,7 +89,7 @@ EXPORT_SYMBOL_GPL(cpu_pm_unregister_notifier);
* Must be called on the affected CPU with interrupts disabled. Platform is
* responsible for ensuring that cpu_pm_enter is not called twice on the same
* CPU before cpu_pm_exit is called. Notified drivers can include VFP
- * co-processor, interrupt controller and it's PM extensions, local CPU
+ * co-processor, interrupt controller and its PM extensions, local CPU
* timers context save/restore which shouldn't be interrupted. Hence it
* must be called with interrupts disabled.
*
@@ -115,13 +115,13 @@ int cpu_pm_enter(void)
EXPORT_SYMBOL_GPL(cpu_pm_enter);
/**
- * cpm_pm_exit - CPU low power exit notifier
+ * cpu_pm_exit - CPU low power exit notifier
*
* Notifies listeners that a single CPU is exiting a low power state that may
* have caused some blocks in the same power domain as the cpu to reset.
*
* Notified drivers can include VFP co-processor, interrupt controller
- * and it's PM extensions, local CPU timers context save/restore which
+ * and its PM extensions, local CPU timers context save/restore which
* shouldn't be interrupted. Hence it must be called with interrupts disabled.
*
* Return conditions are same as __raw_notifier_call_chain.
@@ -139,7 +139,7 @@ int cpu_pm_exit(void)
EXPORT_SYMBOL_GPL(cpu_pm_exit);
/**
- * cpm_cluster_pm_enter - CPU cluster low power entry notifier
+ * cpu_cluster_pm_enter - CPU cluster low power entry notifier
*
* Notifies listeners that all cpus in a power domain are entering a low power
* state that may cause some blocks in the same power domain to reset.
@@ -147,7 +147,7 @@ EXPORT_SYMBOL_GPL(cpu_pm_exit);
* Must be called after cpu_pm_enter has been called on all cpus in the power
* domain, and before cpu_pm_exit has been called on any cpu in the power
* domain. Notified drivers can include VFP co-processor, interrupt controller
- * and it's PM extensions, local CPU timers context save/restore which
+ * and its PM extensions, local CPU timers context save/restore which
* shouldn't be interrupted. Hence it must be called with interrupts disabled.
*
* Must be called with interrupts disabled.
@@ -174,7 +174,7 @@ int cpu_cluster_pm_enter(void)
EXPORT_SYMBOL_GPL(cpu_cluster_pm_enter);
/**
- * cpm_cluster_pm_exit - CPU cluster low power exit notifier
+ * cpu_cluster_pm_exit - CPU cluster low power exit notifier
*
* Notifies listeners that all cpus in a power domain are exiting form a
* low power state that may have caused some blocks in the same power domain
@@ -183,7 +183,7 @@ EXPORT_SYMBOL_GPL(cpu_cluster_pm_enter);
* Must be called after cpu_pm_exit has been called on all cpus in the power
* domain, and before cpu_pm_exit has been called on any cpu in the power
* domain. Notified drivers can include VFP co-processor, interrupt controller
- * and it's PM extensions, local CPU timers context save/restore which
+ * and its PM extensions, local CPU timers context save/restore which
* shouldn't be interrupted. Hence it must be called with interrupts disabled.
*
* Return conditions are same as __raw_notifier_call_chain.
diff --git a/kernel/cred.c b/kernel/cred.c
index 430557ea488f..de728ac50d82 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -207,13 +207,6 @@ void exit_creds(struct task_struct *tsk)
validate_creds(cred);
alter_cred_subscribers(cred, -1);
put_cred(cred);
-
- cred = (struct cred *) tsk->replacement_session_keyring;
- if (cred) {
- tsk->replacement_session_keyring = NULL;
- validate_creds(cred);
- put_cred(cred);
- }
}
/**
@@ -396,8 +389,6 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags)
struct cred *new;
int ret;
- p->replacement_session_keyring = NULL;
-
if (
#ifdef CONFIG_KEYS
!p->cred->thread_keyring &&
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 5b06cbbf6931..d7d71d6ec972 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -253,9 +253,9 @@ perf_cgroup_match(struct perf_event *event)
return !event->cgrp || event->cgrp == cpuctx->cgrp;
}
-static inline void perf_get_cgroup(struct perf_event *event)
+static inline bool perf_tryget_cgroup(struct perf_event *event)
{
- css_get(&event->cgrp->css);
+ return css_tryget(&event->cgrp->css);
}
static inline void perf_put_cgroup(struct perf_event *event)
@@ -484,7 +484,11 @@ static inline int perf_cgroup_connect(int fd, struct perf_event *event,
event->cgrp = cgrp;
/* must be done before we fput() the file */
- perf_get_cgroup(event);
+ if (!perf_tryget_cgroup(event)) {
+ event->cgrp = NULL;
+ ret = -ENOENT;
+ goto out;
+ }
/*
* all events in a group must monitor
@@ -3181,7 +3185,6 @@ static void perf_event_for_each(struct perf_event *event,
event = event->group_leader;
perf_event_for_each_child(event, func);
- func(event);
list_for_each_entry(sibling, &event->sibling_list, group_entry)
perf_event_for_each_child(sibling, func);
mutex_unlock(&ctx->mutex);
diff --git a/kernel/exit.c b/kernel/exit.c
index 910a0716e17a..2f59cc334516 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -72,6 +72,18 @@ static void __unhash_process(struct task_struct *p, bool group_dead)
list_del_rcu(&p->tasks);
list_del_init(&p->sibling);
__this_cpu_dec(process_counts);
+ /*
+ * If we are the last child process in a pid namespace to be
+ * reaped, notify the reaper sleeping zap_pid_ns_processes().
+ */
+ if (IS_ENABLED(CONFIG_PID_NS)) {
+ struct task_struct *parent = p->real_parent;
+
+ if ((task_active_pid_ns(parent)->child_reaper == parent) &&
+ list_empty(&parent->children) &&
+ (parent->flags & PF_EXITING))
+ wake_up_process(parent);
+ }
}
list_del_rcu(&p->thread_group);
}
@@ -643,6 +655,7 @@ static void exit_mm(struct task_struct * tsk)
mm_release(tsk, mm);
if (!mm)
return;
+ sync_mm_rss(mm);
/*
* Serialize with any possible pending coredump.
* We must hold mmap_sem around checking core_state
@@ -719,12 +732,6 @@ static struct task_struct *find_new_reaper(struct task_struct *father)
zap_pid_ns_processes(pid_ns);
write_lock_irq(&tasklist_lock);
- /*
- * We can not clear ->child_reaper or leave it alone.
- * There may by stealth EXIT_DEAD tasks on ->children,
- * forget_original_parent() must move them somewhere.
- */
- pid_ns->child_reaper = init_pid_ns.child_reaper;
} else if (father->signal->has_child_subreaper) {
struct task_struct *reaper;
@@ -884,9 +891,9 @@ static void check_stack_usage(void)
spin_lock(&low_water_lock);
if (free < lowest_to_date) {
- printk(KERN_WARNING "%s used greatest stack depth: %lu bytes "
- "left\n",
- current->comm, free);
+ printk(KERN_WARNING "%s (%d) used greatest stack depth: "
+ "%lu bytes left\n",
+ current->comm, task_pid_nr(current), free);
lowest_to_date = free;
}
spin_unlock(&low_water_lock);
@@ -946,12 +953,13 @@ void do_exit(long code)
exit_signals(tsk); /* sets PF_EXITING */
/*
* tsk->flags are checked in the futex code to protect against
- * an exiting task cleaning up the robust pi futexes.
+ * an exiting task cleaning up the robust pi futexes, and in
+ * task_work_add() to avoid the race with exit_task_work().
*/
smp_mb();
raw_spin_unlock_wait(&tsk->pi_lock);
- exit_irq_thread();
+ exit_task_work(tsk);
if (unlikely(in_atomic()))
printk(KERN_INFO "note: %s[%d] exited with preempt_count %d\n",
@@ -1214,7 +1222,7 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
unsigned long state;
int retval, status, traced;
pid_t pid = task_pid_vnr(p);
- uid_t uid = from_kuid_munged(current_user_ns(), __task_cred(p)->uid);
+ uid_t uid = from_kuid_munged(current_user_ns(), task_uid(p));
struct siginfo __user *infop;
if (!likely(wo->wo_flags & WEXITED))
diff --git a/kernel/fork.c b/kernel/fork.c
index 31a32c7dd169..ab5211b9e622 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -787,9 +787,6 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm)
/* Get rid of any cached register state */
deactivate_mm(tsk, mm);
- if (tsk->vfork_done)
- complete_vfork_done(tsk);
-
/*
* If we're exiting normally, clear a user-space tid field if
* requested. We leave this alone when dying by signal, to leave
@@ -810,6 +807,13 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm)
}
tsk->clear_child_tid = NULL;
}
+
+ /*
+ * All done, finally we can wake up parent and return this mm to him.
+ * Also kthread_stop() uses this completion for synchronization.
+ */
+ if (tsk->vfork_done)
+ complete_vfork_done(tsk);
}
/*
@@ -1411,6 +1415,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
*/
p->group_leader = p;
INIT_LIST_HEAD(&p->thread_group);
+ INIT_HLIST_HEAD(&p->task_works);
/* Now that the task is set up, run cgroup callbacks if
* necessary. We need to run them before the task is visible
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index fc275e4f629b..eebd6d5cfb44 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -275,8 +275,10 @@ void handle_nested_irq(unsigned int irq)
kstat_incr_irqs_this_cpu(irq, desc);
action = desc->action;
- if (unlikely(!action || irqd_irq_disabled(&desc->irq_data)))
+ if (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) {
+ desc->istate |= IRQS_PENDING;
goto out_unlock;
+ }
irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
raw_spin_unlock_irq(&desc->lock);
@@ -324,8 +326,10 @@ handle_simple_irq(unsigned int irq, struct irq_desc *desc)
desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
kstat_incr_irqs_this_cpu(irq, desc);
- if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data)))
+ if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
+ desc->istate |= IRQS_PENDING;
goto out_unlock;
+ }
handle_irq_event(desc);
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index 8e5c56b3b7d9..001fa5bab490 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -101,6 +101,9 @@ extern int irq_select_affinity_usr(unsigned int irq, struct cpumask *mask);
extern void irq_set_thread_affinity(struct irq_desc *desc);
+extern int irq_do_set_affinity(struct irq_data *data,
+ const struct cpumask *dest, bool force);
+
/* Inline functions for support of irq chips on slow busses */
static inline void chip_bus_lock(struct irq_desc *desc)
{
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index bb32326afe87..8c548232ba39 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -7,6 +7,8 @@
* This file contains driver APIs to the irq subsystem.
*/
+#define pr_fmt(fmt) "genirq: " fmt
+
#include <linux/irq.h>
#include <linux/kthread.h>
#include <linux/module.h>
@@ -14,6 +16,7 @@
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/sched.h>
+#include <linux/task_work.h>
#include "internals.h"
@@ -139,6 +142,25 @@ static inline void
irq_get_pending(struct cpumask *mask, struct irq_desc *desc) { }
#endif
+int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
+ bool force)
+{
+ struct irq_desc *desc = irq_data_to_desc(data);
+ struct irq_chip *chip = irq_data_get_irq_chip(data);
+ int ret;
+
+ ret = chip->irq_set_affinity(data, mask, false);
+ switch (ret) {
+ case IRQ_SET_MASK_OK:
+ cpumask_copy(data->affinity, mask);
+ case IRQ_SET_MASK_OK_NOCOPY:
+ irq_set_thread_affinity(desc);
+ ret = 0;
+ }
+
+ return ret;
+}
+
int __irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask)
{
struct irq_chip *chip = irq_data_get_irq_chip(data);
@@ -149,14 +171,7 @@ int __irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask)
return -EINVAL;
if (irq_can_move_pcntxt(data)) {
- ret = chip->irq_set_affinity(data, mask, false);
- switch (ret) {
- case IRQ_SET_MASK_OK:
- cpumask_copy(data->affinity, mask);
- case IRQ_SET_MASK_OK_NOCOPY:
- irq_set_thread_affinity(desc);
- ret = 0;
- }
+ ret = irq_do_set_affinity(data, mask, false);
} else {
irqd_set_move_pending(data);
irq_copy_pending(desc, mask);
@@ -280,9 +295,8 @@ EXPORT_SYMBOL_GPL(irq_set_affinity_notifier);
static int
setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask)
{
- struct irq_chip *chip = irq_desc_get_chip(desc);
struct cpumask *set = irq_default_affinity;
- int ret, node = desc->irq_data.node;
+ int node = desc->irq_data.node;
/* Excludes PER_CPU and NO_BALANCE interrupts */
if (!irq_can_set_affinity(irq))
@@ -308,13 +322,7 @@ setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask)
if (cpumask_intersects(mask, nodemask))
cpumask_and(mask, mask, nodemask);
}
- ret = chip->irq_set_affinity(&desc->irq_data, mask, false);
- switch (ret) {
- case IRQ_SET_MASK_OK:
- cpumask_copy(desc->irq_data.affinity, mask);
- case IRQ_SET_MASK_OK_NOCOPY:
- irq_set_thread_affinity(desc);
- }
+ irq_do_set_affinity(&desc->irq_data, mask, false);
return 0;
}
#else
@@ -565,7 +573,7 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
* IRQF_TRIGGER_* but the PIC does not support multiple
* flow-types?
*/
- pr_debug("genirq: No set_type function for IRQ %d (%s)\n", irq,
+ pr_debug("No set_type function for IRQ %d (%s)\n", irq,
chip ? (chip->name ? : "unknown") : "unknown");
return 0;
}
@@ -600,7 +608,7 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
ret = 0;
break;
default:
- pr_err("genirq: Setting trigger mode %lu for irq %u failed (%pF)\n",
+ pr_err("Setting trigger mode %lu for irq %u failed (%pF)\n",
flags, irq, chip->irq_set_type);
}
if (unmask)
@@ -773,11 +781,39 @@ static void wake_threads_waitq(struct irq_desc *desc)
wake_up(&desc->wait_for_threads);
}
+static void irq_thread_dtor(struct task_work *unused)
+{
+ struct task_struct *tsk = current;
+ struct irq_desc *desc;
+ struct irqaction *action;
+
+ if (WARN_ON_ONCE(!(current->flags & PF_EXITING)))
+ return;
+
+ action = kthread_data(tsk);
+
+ pr_err("exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
+ tsk->comm ? tsk->comm : "", tsk->pid, action->irq);
+
+
+ desc = irq_to_desc(action->irq);
+ /*
+ * If IRQTF_RUNTHREAD is set, we need to decrement
+ * desc->threads_active and wake possible waiters.
+ */
+ if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
+ wake_threads_waitq(desc);
+
+ /* Prevent a stale desc->threads_oneshot */
+ irq_finalize_oneshot(desc, action);
+}
+
/*
* Interrupt handler thread
*/
static int irq_thread(void *data)
{
+ struct task_work on_exit_work;
static const struct sched_param param = {
.sched_priority = MAX_USER_RT_PRIO/2,
};
@@ -793,7 +829,9 @@ static int irq_thread(void *data)
handler_fn = irq_thread_fn;
sched_setscheduler(current, SCHED_FIFO, &param);
- current->irq_thread = 1;
+
+ init_task_work(&on_exit_work, irq_thread_dtor, NULL);
+ task_work_add(current, &on_exit_work, false);
while (!irq_wait_for_interrupt(action)) {
irqreturn_t action_ret;
@@ -815,44 +853,11 @@ static int irq_thread(void *data)
* cannot touch the oneshot mask at this point anymore as
* __setup_irq() might have given out currents thread_mask
* again.
- *
- * Clear irq_thread. Otherwise exit_irq_thread() would make
- * fuzz about an active irq thread going into nirvana.
*/
- current->irq_thread = 0;
+ task_work_cancel(current, irq_thread_dtor);
return 0;
}
-/*
- * Called from do_exit()
- */
-void exit_irq_thread(void)
-{
- struct task_struct *tsk = current;
- struct irq_desc *desc;
- struct irqaction *action;
-
- if (!tsk->irq_thread)
- return;
-
- action = kthread_data(tsk);
-
- pr_err("genirq: exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
- tsk->comm ? tsk->comm : "", tsk->pid, action->irq);
-
- desc = irq_to_desc(action->irq);
-
- /*
- * If IRQTF_RUNTHREAD is set, we need to decrement
- * desc->threads_active and wake possible waiters.
- */
- if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags))
- wake_threads_waitq(desc);
-
- /* Prevent a stale desc->threads_oneshot */
- irq_finalize_oneshot(desc, action);
-}
-
static void irq_setup_forced_threading(struct irqaction *new)
{
if (!force_irqthreads)
@@ -1044,7 +1049,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
* has. The type flags are unreliable as the
* underlying chip implementation can override them.
*/
- pr_err("genirq: Threaded irq requested with handler=NULL and !ONESHOT for irq %d\n",
+ pr_err("Threaded irq requested with handler=NULL and !ONESHOT for irq %d\n",
irq);
ret = -EINVAL;
goto out_mask;
@@ -1095,7 +1100,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
if (nmsk != omsk)
/* hope the handler works with current trigger mode */
- pr_warning("genirq: irq %d uses trigger mode %u; requested %u\n",
+ pr_warning("irq %d uses trigger mode %u; requested %u\n",
irq, nmsk, omsk);
}
@@ -1133,7 +1138,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
mismatch:
if (!(new->flags & IRQF_PROBE_SHARED)) {
- pr_err("genirq: Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
+ pr_err("Flags mismatch irq %d. %08x (%s) vs. %08x (%s)\n",
irq, new->flags, new->name, old->flags, old->name);
#ifdef CONFIG_DEBUG_SHIRQ
dump_stack();
diff --git a/kernel/irq/migration.c b/kernel/irq/migration.c
index c3c89751b327..ca3f4aaff707 100644
--- a/kernel/irq/migration.c
+++ b/kernel/irq/migration.c
@@ -42,17 +42,8 @@ void irq_move_masked_irq(struct irq_data *idata)
* For correct operation this depends on the caller
* masking the irqs.
*/
- if (likely(cpumask_any_and(desc->pending_mask, cpu_online_mask)
- < nr_cpu_ids)) {
- int ret = chip->irq_set_affinity(&desc->irq_data,
- desc->pending_mask, false);
- switch (ret) {
- case IRQ_SET_MASK_OK:
- cpumask_copy(desc->irq_data.affinity, desc->pending_mask);
- case IRQ_SET_MASK_OK_NOCOPY:
- irq_set_thread_affinity(desc);
- }
- }
+ if (cpumask_any_and(desc->pending_mask, cpu_online_mask) < nr_cpu_ids)
+ irq_do_set_affinity(&desc->irq_data, desc->pending_mask, false);
cpumask_clear(desc->pending_mask);
}
diff --git a/kernel/kcmp.c b/kernel/kcmp.c
new file mode 100644
index 000000000000..30b7b225306c
--- /dev/null
+++ b/kernel/kcmp.c
@@ -0,0 +1,196 @@
+#include <linux/kernel.h>
+#include <linux/syscalls.h>
+#include <linux/fdtable.h>
+#include <linux/string.h>
+#include <linux/random.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/cache.h>
+#include <linux/bug.h>
+#include <linux/err.h>
+#include <linux/kcmp.h>
+
+#include <asm/unistd.h>
+
+/*
+ * We don't expose the real in-memory order of objects for security reasons.
+ * But still the comparison results should be suitable for sorting. So we
+ * obfuscate kernel pointers values and compare the production instead.
+ *
+ * The obfuscation is done in two steps. First we xor the kernel pointer with
+ * a random value, which puts pointer into a new position in a reordered space.
+ * Secondly we multiply the xor production with a large odd random number to
+ * permute its bits even more (the odd multiplier guarantees that the product
+ * is unique ever after the high bits are truncated, since any odd number is
+ * relative prime to 2^n).
+ *
+ * Note also that the obfuscation itself is invisible to userspace and if needed
+ * it can be changed to an alternate scheme.
+ */
+static unsigned long cookies[KCMP_TYPES][2] __read_mostly;
+
+static long kptr_obfuscate(long v, int type)
+{
+ return (v ^ cookies[type][0]) * cookies[type][1];
+}
+
+/*
+ * 0 - equal, i.e. v1 = v2
+ * 1 - less than, i.e. v1 < v2
+ * 2 - greater than, i.e. v1 > v2
+ * 3 - not equal but ordering unavailable (reserved for future)
+ */
+static int kcmp_ptr(void *v1, void *v2, enum kcmp_type type)
+{
+ long ret;
+
+ ret = kptr_obfuscate((long)v1, type) - kptr_obfuscate((long)v2, type);
+
+ return (ret < 0) | ((ret > 0) << 1);
+}
+
+/* The caller must have pinned the task */
+static struct file *
+get_file_raw_ptr(struct task_struct *task, unsigned int idx)
+{
+ struct file *file = NULL;
+
+ task_lock(task);
+ rcu_read_lock();
+
+ if (task->files)
+ file = fcheck_files(task->files, idx);
+
+ rcu_read_unlock();
+ task_unlock(task);
+
+ return file;
+}
+
+static void kcmp_unlock(struct mutex *m1, struct mutex *m2)
+{
+ if (likely(m2 != m1))
+ mutex_unlock(m2);
+ mutex_unlock(m1);
+}
+
+static int kcmp_lock(struct mutex *m1, struct mutex *m2)
+{
+ int err;
+
+ if (m2 > m1)
+ swap(m1, m2);
+
+ err = mutex_lock_killable(m1);
+ if (!err && likely(m1 != m2)) {
+ err = mutex_lock_killable_nested(m2, SINGLE_DEPTH_NESTING);
+ if (err)
+ mutex_unlock(m1);
+ }
+
+ return err;
+}
+
+SYSCALL_DEFINE5(kcmp, pid_t, pid1, pid_t, pid2, int, type,
+ unsigned long, idx1, unsigned long, idx2)
+{
+ struct task_struct *task1, *task2;
+ int ret;
+
+ rcu_read_lock();
+
+ /*
+ * Tasks are looked up in caller's PID namespace only.
+ */
+ task1 = find_task_by_vpid(pid1);
+ task2 = find_task_by_vpid(pid2);
+ if (!task1 || !task2)
+ goto err_no_task;
+
+ get_task_struct(task1);
+ get_task_struct(task2);
+
+ rcu_read_unlock();
+
+ /*
+ * One should have enough rights to inspect task details.
+ */
+ ret = kcmp_lock(&task1->signal->cred_guard_mutex,
+ &task2->signal->cred_guard_mutex);
+ if (ret)
+ goto err;
+ if (!ptrace_may_access(task1, PTRACE_MODE_READ) ||
+ !ptrace_may_access(task2, PTRACE_MODE_READ)) {
+ ret = -EPERM;
+ goto err_unlock;
+ }
+
+ switch (type) {
+ case KCMP_FILE: {
+ struct file *filp1, *filp2;
+
+ filp1 = get_file_raw_ptr(task1, idx1);
+ filp2 = get_file_raw_ptr(task2, idx2);
+
+ if (filp1 && filp2)
+ ret = kcmp_ptr(filp1, filp2, KCMP_FILE);
+ else
+ ret = -EBADF;
+ break;
+ }
+ case KCMP_VM:
+ ret = kcmp_ptr(task1->mm, task2->mm, KCMP_VM);
+ break;
+ case KCMP_FILES:
+ ret = kcmp_ptr(task1->files, task2->files, KCMP_FILES);
+ break;
+ case KCMP_FS:
+ ret = kcmp_ptr(task1->fs, task2->fs, KCMP_FS);
+ break;
+ case KCMP_SIGHAND:
+ ret = kcmp_ptr(task1->sighand, task2->sighand, KCMP_SIGHAND);
+ break;
+ case KCMP_IO:
+ ret = kcmp_ptr(task1->io_context, task2->io_context, KCMP_IO);
+ break;
+ case KCMP_SYSVSEM:
+#ifdef CONFIG_SYSVIPC
+ ret = kcmp_ptr(task1->sysvsem.undo_list,
+ task2->sysvsem.undo_list,
+ KCMP_SYSVSEM);
+#else
+ ret = -EOPNOTSUPP;
+#endif
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+err_unlock:
+ kcmp_unlock(&task1->signal->cred_guard_mutex,
+ &task2->signal->cred_guard_mutex);
+err:
+ put_task_struct(task1);
+ put_task_struct(task2);
+
+ return ret;
+
+err_no_task:
+ rcu_read_unlock();
+ return -ESRCH;
+}
+
+static __init int kcmp_cookies_init(void)
+{
+ int i;
+
+ get_random_bytes(cookies, sizeof(cookies));
+
+ for (i = 0; i < KCMP_TYPES; i++)
+ cookies[i][1] |= (~(~0UL >> 1) | 1);
+
+ return 0;
+}
+arch_initcall(kcmp_cookies_init);
diff --git a/kernel/kmod.c b/kernel/kmod.c
index 05698a7415fe..ff2c7cb86d77 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -221,13 +221,12 @@ fail:
return 0;
}
-void call_usermodehelper_freeinfo(struct subprocess_info *info)
+static void call_usermodehelper_freeinfo(struct subprocess_info *info)
{
if (info->cleanup)
(*info->cleanup)(info);
kfree(info);
}
-EXPORT_SYMBOL(call_usermodehelper_freeinfo);
static void umh_complete(struct subprocess_info *sub_info)
{
@@ -410,7 +409,7 @@ EXPORT_SYMBOL_GPL(usermodehelper_read_unlock);
/**
* __usermodehelper_set_disable_depth - Modify usermodehelper_disabled.
- * depth: New value to assign to usermodehelper_disabled.
+ * @depth: New value to assign to usermodehelper_disabled.
*
* Change the value of usermodehelper_disabled (under umhelper_sem locked for
* writing) and wakeup tasks waiting for it to change.
@@ -479,6 +478,7 @@ static void helper_unlock(void)
* structure. This should be passed to call_usermodehelper_exec to
* exec the process and free the structure.
*/
+static
struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
char **envp, gfp_t gfp_mask)
{
@@ -494,7 +494,6 @@ struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
out:
return sub_info;
}
-EXPORT_SYMBOL(call_usermodehelper_setup);
/**
* call_usermodehelper_setfns - set a cleanup/init function
@@ -512,6 +511,7 @@ EXPORT_SYMBOL(call_usermodehelper_setup);
* Function must be runnable in either a process context or the
* context in which call_usermodehelper_exec is called.
*/
+static
void call_usermodehelper_setfns(struct subprocess_info *info,
int (*init)(struct subprocess_info *info, struct cred *new),
void (*cleanup)(struct subprocess_info *info),
@@ -521,7 +521,6 @@ void call_usermodehelper_setfns(struct subprocess_info *info,
info->init = init;
info->data = data;
}
-EXPORT_SYMBOL(call_usermodehelper_setfns);
/**
* call_usermodehelper_exec - start a usermode application
@@ -535,6 +534,7 @@ EXPORT_SYMBOL(call_usermodehelper_setfns);
* asynchronously if wait is not set, and runs as a child of keventd.
* (ie. it runs with full root capabilities).
*/
+static
int call_usermodehelper_exec(struct subprocess_info *sub_info, int wait)
{
DECLARE_COMPLETION_ONSTACK(done);
@@ -576,7 +576,25 @@ unlock:
helper_unlock();
return retval;
}
-EXPORT_SYMBOL(call_usermodehelper_exec);
+
+int call_usermodehelper_fns(
+ char *path, char **argv, char **envp, int wait,
+ int (*init)(struct subprocess_info *info, struct cred *new),
+ void (*cleanup)(struct subprocess_info *), void *data)
+{
+ struct subprocess_info *info;
+ gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
+
+ info = call_usermodehelper_setup(path, argv, envp, gfp_mask);
+
+ if (info == NULL)
+ return -ENOMEM;
+
+ call_usermodehelper_setfns(info, init, cleanup, data);
+
+ return call_usermodehelper_exec(info, wait);
+}
+EXPORT_SYMBOL(call_usermodehelper_fns);
static int proc_cap_handler(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
diff --git a/kernel/lglock.c b/kernel/lglock.c
new file mode 100644
index 000000000000..6535a667a5a7
--- /dev/null
+++ b/kernel/lglock.c
@@ -0,0 +1,89 @@
+/* See include/linux/lglock.h for description */
+#include <linux/module.h>
+#include <linux/lglock.h>
+#include <linux/cpu.h>
+#include <linux/string.h>
+
+/*
+ * Note there is no uninit, so lglocks cannot be defined in
+ * modules (but it's fine to use them from there)
+ * Could be added though, just undo lg_lock_init
+ */
+
+void lg_lock_init(struct lglock *lg, char *name)
+{
+ LOCKDEP_INIT_MAP(&lg->lock_dep_map, name, &lg->lock_key, 0);
+}
+EXPORT_SYMBOL(lg_lock_init);
+
+void lg_local_lock(struct lglock *lg)
+{
+ arch_spinlock_t *lock;
+
+ preempt_disable();
+ rwlock_acquire_read(&lg->lock_dep_map, 0, 0, _RET_IP_);
+ lock = this_cpu_ptr(lg->lock);
+ arch_spin_lock(lock);
+}
+EXPORT_SYMBOL(lg_local_lock);
+
+void lg_local_unlock(struct lglock *lg)
+{
+ arch_spinlock_t *lock;
+
+ rwlock_release(&lg->lock_dep_map, 1, _RET_IP_);
+ lock = this_cpu_ptr(lg->lock);
+ arch_spin_unlock(lock);
+ preempt_enable();
+}
+EXPORT_SYMBOL(lg_local_unlock);
+
+void lg_local_lock_cpu(struct lglock *lg, int cpu)
+{
+ arch_spinlock_t *lock;
+
+ preempt_disable();
+ rwlock_acquire_read(&lg->lock_dep_map, 0, 0, _RET_IP_);
+ lock = per_cpu_ptr(lg->lock, cpu);
+ arch_spin_lock(lock);
+}
+EXPORT_SYMBOL(lg_local_lock_cpu);
+
+void lg_local_unlock_cpu(struct lglock *lg, int cpu)
+{
+ arch_spinlock_t *lock;
+
+ rwlock_release(&lg->lock_dep_map, 1, _RET_IP_);
+ lock = per_cpu_ptr(lg->lock, cpu);
+ arch_spin_unlock(lock);
+ preempt_enable();
+}
+EXPORT_SYMBOL(lg_local_unlock_cpu);
+
+void lg_global_lock(struct lglock *lg)
+{
+ int i;
+
+ preempt_disable();
+ rwlock_acquire(&lg->lock_dep_map, 0, 0, _RET_IP_);
+ for_each_possible_cpu(i) {
+ arch_spinlock_t *lock;
+ lock = per_cpu_ptr(lg->lock, i);
+ arch_spin_lock(lock);
+ }
+}
+EXPORT_SYMBOL(lg_global_lock);
+
+void lg_global_unlock(struct lglock *lg)
+{
+ int i;
+
+ rwlock_release(&lg->lock_dep_map, 1, _RET_IP_);
+ for_each_possible_cpu(i) {
+ arch_spinlock_t *lock;
+ lock = per_cpu_ptr(lg->lock, i);
+ arch_spin_unlock(lock);
+ }
+ preempt_enable();
+}
+EXPORT_SYMBOL(lg_global_unlock);
diff --git a/kernel/panic.c b/kernel/panic.c
index 8ed89a175d79..d2a5f4ecc6dd 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -27,7 +27,7 @@
#define PANIC_TIMER_STEP 100
#define PANIC_BLINK_SPD 18
-int panic_on_oops;
+int panic_on_oops = CONFIG_PANIC_ON_OOPS_VALUE;
static unsigned long tainted_mask;
static int pause_on_oops;
static int pause_on_oops_flag;
@@ -108,8 +108,6 @@ void panic(const char *fmt, ...)
*/
crash_kexec(NULL);
- kmsg_dump(KMSG_DUMP_PANIC);
-
/*
* Note smp_send_stop is the usual smp shutdown function, which
* unfortunately means it may not be hardened to work in a panic
@@ -117,6 +115,8 @@ void panic(const char *fmt, ...)
*/
smp_send_stop();
+ kmsg_dump(KMSG_DUMP_PANIC);
+
atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
bust_spinlocks(0);
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index 57bc1fd35b3c..b3c7fd554250 100644
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -149,7 +149,12 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns)
{
int nr;
int rc;
- struct task_struct *task;
+ struct task_struct *task, *me = current;
+
+ /* Ignore SIGCHLD causing any terminated children to autoreap */
+ spin_lock_irq(&me->sighand->siglock);
+ me->sighand->action[SIGCHLD - 1].sa.sa_handler = SIG_IGN;
+ spin_unlock_irq(&me->sighand->siglock);
/*
* The last thread in the cgroup-init thread group is terminating.
@@ -179,11 +184,31 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns)
}
read_unlock(&tasklist_lock);
+ /* Firstly reap the EXIT_ZOMBIE children we may have. */
do {
clear_thread_flag(TIF_SIGPENDING);
rc = sys_wait4(-1, NULL, __WALL, NULL);
} while (rc != -ECHILD);
+ /*
+ * sys_wait4() above can't reap the TASK_DEAD children.
+ * Make sure they all go away, see __unhash_process().
+ */
+ for (;;) {
+ bool need_wait = false;
+
+ read_lock(&tasklist_lock);
+ if (!list_empty(&current->children)) {
+ __set_current_state(TASK_UNINTERRUPTIBLE);
+ need_wait = true;
+ }
+ read_unlock(&tasklist_lock);
+
+ if (!need_wait)
+ break;
+ schedule();
+ }
+
if (pid_ns->reboot)
current->signal->group_exit_code = pid_ns->reboot;
@@ -191,6 +216,7 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns)
return;
}
+#ifdef CONFIG_CHECKPOINT_RESTORE
static int pid_ns_ctl_handler(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
@@ -218,8 +244,8 @@ static struct ctl_table pid_ns_ctl_table[] = {
},
{ }
};
-
static struct ctl_path kern_path[] = { { .procname = "kernel", }, { } };
+#endif /* CONFIG_CHECKPOINT_RESTORE */
int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
{
@@ -253,7 +279,10 @@ int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
static __init int pid_namespaces_init(void)
{
pid_ns_cachep = KMEM_CACHE(pid_namespace, SLAB_PANIC);
+
+#ifdef CONFIG_CHECKPOINT_RESTORE
register_sysctl_paths(kern_path, pid_ns_ctl_table);
+#endif
return 0;
}
diff --git a/kernel/printk.c b/kernel/printk.c
index 32462d2b364a..a2276b916769 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -227,10 +227,10 @@ static u32 clear_idx;
#define LOG_LINE_MAX 1024
/* record buffer */
-#if !defined(CONFIG_64BIT) || defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
+#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
#define LOG_ALIGN 4
#else
-#define LOG_ALIGN 8
+#define LOG_ALIGN __alignof__(struct log)
#endif
#define __LOG_BUF_LEN (1 << CONFIG_LOG_BUF_SHIFT)
static char __log_buf[__LOG_BUF_LEN] __aligned(LOG_ALIGN);
@@ -414,7 +414,9 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf,
if (!user)
return -EBADF;
- mutex_lock(&user->lock);
+ ret = mutex_lock_interruptible(&user->lock);
+ if (ret)
+ return ret;
raw_spin_lock(&logbuf_lock);
while (user->seq == log_next_seq) {
if (file->f_flags & O_NONBLOCK) {
@@ -878,7 +880,9 @@ static int syslog_print(char __user *buf, int size)
syslog_seq++;
raw_spin_unlock_irq(&logbuf_lock);
- if (len > 0 && copy_to_user(buf, text, len))
+ if (len > size)
+ len = -EINVAL;
+ else if (len > 0 && copy_to_user(buf, text, len))
len = -EFAULT;
kfree(text);
@@ -909,7 +913,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
/*
* Find first record that fits, including all following records,
* into the user-provided buffer for this dump.
- */
+ */
seq = clear_seq;
idx = clear_idx;
while (seq < log_next_seq) {
@@ -919,6 +923,8 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
idx = log_next(idx);
seq++;
}
+
+ /* move first record forward until length fits into the buffer */
seq = clear_seq;
idx = clear_idx;
while (len > size && seq < log_next_seq) {
@@ -929,7 +935,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
seq++;
}
- /* last message in this dump */
+ /* last message fitting into this dump */
next_seq = log_next_seq;
len = 0;
@@ -974,6 +980,7 @@ int do_syslog(int type, char __user *buf, int len, bool from_file)
{
bool clear = false;
static int saved_console_loglevel = -1;
+ static DEFINE_MUTEX(syslog_mutex);
int error;
error = check_syslog_permissions(type, from_file);
@@ -1000,11 +1007,17 @@ int do_syslog(int type, char __user *buf, int len, bool from_file)
error = -EFAULT;
goto out;
}
+ error = mutex_lock_interruptible(&syslog_mutex);
+ if (error)
+ goto out;
error = wait_event_interruptible(log_wait,
syslog_seq != log_next_seq);
- if (error)
+ if (error) {
+ mutex_unlock(&syslog_mutex);
goto out;
+ }
error = syslog_print(buf, len);
+ mutex_unlock(&syslog_mutex);
break;
/* Read/clear last kernel messages */
case SYSLOG_ACTION_READ_CLEAR:
@@ -2300,48 +2313,210 @@ module_param_named(always_kmsg_dump, always_kmsg_dump, bool, S_IRUGO | S_IWUSR);
* kmsg_dump - dump kernel log to kernel message dumpers.
* @reason: the reason (oops, panic etc) for dumping
*
- * Iterate through each of the dump devices and call the oops/panic
- * callbacks with the log buffer.
+ * Call each of the registered dumper's dump() callback, which can
+ * retrieve the kmsg records with kmsg_dump_get_line() or
+ * kmsg_dump_get_buffer().
*/
void kmsg_dump(enum kmsg_dump_reason reason)
{
- u64 idx;
struct kmsg_dumper *dumper;
- const char *s1, *s2;
- unsigned long l1, l2;
unsigned long flags;
if ((reason > KMSG_DUMP_OOPS) && !always_kmsg_dump)
return;
- /* Theoretically, the log could move on after we do this, but
- there's not a lot we can do about that. The new messages
- will overwrite the start of what we dump. */
+ rcu_read_lock();
+ list_for_each_entry_rcu(dumper, &dump_list, list) {
+ if (dumper->max_reason && reason > dumper->max_reason)
+ continue;
+
+ /* initialize iterator with data about the stored records */
+ dumper->active = true;
+
+ raw_spin_lock_irqsave(&logbuf_lock, flags);
+ dumper->cur_seq = clear_seq;
+ dumper->cur_idx = clear_idx;
+ dumper->next_seq = log_next_seq;
+ dumper->next_idx = log_next_idx;
+ raw_spin_unlock_irqrestore(&logbuf_lock, flags);
+
+ /* invoke dumper which will iterate over records */
+ dumper->dump(dumper, reason);
+
+ /* reset iterator */
+ dumper->active = false;
+ }
+ rcu_read_unlock();
+}
+
+/**
+ * kmsg_dump_get_line - retrieve one kmsg log line
+ * @dumper: registered kmsg dumper
+ * @syslog: include the "<4>" prefixes
+ * @line: buffer to copy the line to
+ * @size: maximum size of the buffer
+ * @len: length of line placed into buffer
+ *
+ * Start at the beginning of the kmsg buffer, with the oldest kmsg
+ * record, and copy one record into the provided buffer.
+ *
+ * Consecutive calls will return the next available record moving
+ * towards the end of the buffer with the youngest messages.
+ *
+ * A return value of FALSE indicates that there are no more records to
+ * read.
+ */
+bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
+ char *line, size_t size, size_t *len)
+{
+ unsigned long flags;
+ struct log *msg;
+ size_t l = 0;
+ bool ret = false;
+
+ if (!dumper->active)
+ goto out;
raw_spin_lock_irqsave(&logbuf_lock, flags);
- if (syslog_seq < log_first_seq)
- idx = syslog_idx;
- else
- idx = log_first_idx;
+ if (dumper->cur_seq < log_first_seq) {
+ /* messages are gone, move to first available one */
+ dumper->cur_seq = log_first_seq;
+ dumper->cur_idx = log_first_idx;
+ }
+
+ /* last entry */
+ if (dumper->cur_seq >= log_next_seq) {
+ raw_spin_unlock_irqrestore(&logbuf_lock, flags);
+ goto out;
+ }
- if (idx > log_next_idx) {
- s1 = log_buf;
- l1 = log_next_idx;
+ msg = log_from_idx(dumper->cur_idx);
+ l = msg_print_text(msg, syslog,
+ line, size);
- s2 = log_buf + idx;
- l2 = log_buf_len - idx;
- } else {
- s1 = "";
- l1 = 0;
+ dumper->cur_idx = log_next(dumper->cur_idx);
+ dumper->cur_seq++;
+ ret = true;
+ raw_spin_unlock_irqrestore(&logbuf_lock, flags);
+out:
+ if (len)
+ *len = l;
+ return ret;
+}
+EXPORT_SYMBOL_GPL(kmsg_dump_get_line);
+
+/**
+ * kmsg_dump_get_buffer - copy kmsg log lines
+ * @dumper: registered kmsg dumper
+ * @syslog: include the "<4>" prefixes
+ * @line: buffer to copy the line to
+ * @size: maximum size of the buffer
+ * @len: length of line placed into buffer
+ *
+ * Start at the end of the kmsg buffer and fill the provided buffer
+ * with as many of the the *youngest* kmsg records that fit into it.
+ * If the buffer is large enough, all available kmsg records will be
+ * copied with a single call.
+ *
+ * Consecutive calls will fill the buffer with the next block of
+ * available older records, not including the earlier retrieved ones.
+ *
+ * A return value of FALSE indicates that there are no more records to
+ * read.
+ */
+bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
+ char *buf, size_t size, size_t *len)
+{
+ unsigned long flags;
+ u64 seq;
+ u32 idx;
+ u64 next_seq;
+ u32 next_idx;
+ size_t l = 0;
+ bool ret = false;
+
+ if (!dumper->active)
+ goto out;
+
+ raw_spin_lock_irqsave(&logbuf_lock, flags);
+ if (dumper->cur_seq < log_first_seq) {
+ /* messages are gone, move to first available one */
+ dumper->cur_seq = log_first_seq;
+ dumper->cur_idx = log_first_idx;
+ }
+
+ /* last entry */
+ if (dumper->cur_seq >= dumper->next_seq) {
+ raw_spin_unlock_irqrestore(&logbuf_lock, flags);
+ goto out;
+ }
+
+ /* calculate length of entire buffer */
+ seq = dumper->cur_seq;
+ idx = dumper->cur_idx;
+ while (seq < dumper->next_seq) {
+ struct log *msg = log_from_idx(idx);
+
+ l += msg_print_text(msg, true, NULL, 0);
+ idx = log_next(idx);
+ seq++;
+ }
- s2 = log_buf + idx;
- l2 = log_next_idx - idx;
+ /* move first record forward until length fits into the buffer */
+ seq = dumper->cur_seq;
+ idx = dumper->cur_idx;
+ while (l > size && seq < dumper->next_seq) {
+ struct log *msg = log_from_idx(idx);
+
+ l -= msg_print_text(msg, true, NULL, 0);
+ idx = log_next(idx);
+ seq++;
+ }
+
+ /* last message in next interation */
+ next_seq = seq;
+ next_idx = idx;
+
+ l = 0;
+ while (seq < dumper->next_seq) {
+ struct log *msg = log_from_idx(idx);
+
+ l += msg_print_text(msg, syslog,
+ buf + l, size - l);
+
+ idx = log_next(idx);
+ seq++;
}
+
+ dumper->next_seq = next_seq;
+ dumper->next_idx = next_idx;
+ ret = true;
raw_spin_unlock_irqrestore(&logbuf_lock, flags);
+out:
+ if (len)
+ *len = l;
+ return ret;
+}
+EXPORT_SYMBOL_GPL(kmsg_dump_get_buffer);
- rcu_read_lock();
- list_for_each_entry_rcu(dumper, &dump_list, list)
- dumper->dump(dumper, reason, s1, l1, s2, l2);
- rcu_read_unlock();
+/**
+ * kmsg_dump_rewind - reset the interator
+ * @dumper: registered kmsg dumper
+ *
+ * Reset the dumper's iterator so that kmsg_dump_get_line() and
+ * kmsg_dump_get_buffer() can be called again and used multiple
+ * times within the same dumper.dump() callback.
+ */
+void kmsg_dump_rewind(struct kmsg_dumper *dumper)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&logbuf_lock, flags);
+ dumper->cur_seq = clear_seq;
+ dumper->cur_idx = clear_idx;
+ dumper->next_seq = log_next_seq;
+ dumper->next_idx = log_next_idx;
+ raw_spin_unlock_irqrestore(&logbuf_lock, flags);
}
+EXPORT_SYMBOL_GPL(kmsg_dump_rewind);
#endif
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 0da7b88d92d0..3b0f1337f75b 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -1397,6 +1397,8 @@ static void rcu_adopt_orphan_cbs(struct rcu_state *rsp)
rdp->qlen_lazy += rsp->qlen_lazy;
rdp->qlen += rsp->qlen;
rdp->n_cbs_adopted += rsp->qlen;
+ if (rsp->qlen_lazy != rsp->qlen)
+ rcu_idle_count_callbacks_posted();
rsp->qlen_lazy = 0;
rsp->qlen = 0;
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index 7f5d138dedf5..ea056495783e 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -84,6 +84,20 @@ struct rcu_dynticks {
/* Process level is worth LLONG_MAX/2. */
int dynticks_nmi_nesting; /* Track NMI nesting level. */
atomic_t dynticks; /* Even value for idle, else odd. */
+#ifdef CONFIG_RCU_FAST_NO_HZ
+ int dyntick_drain; /* Prepare-for-idle state variable. */
+ unsigned long dyntick_holdoff;
+ /* No retries for the jiffy of failure. */
+ struct timer_list idle_gp_timer;
+ /* Wake up CPU sleeping with callbacks. */
+ unsigned long idle_gp_timer_expires;
+ /* When to wake up CPU (for repost). */
+ bool idle_first_pass; /* First pass of attempt to go idle? */
+ unsigned long nonlazy_posted;
+ /* # times non-lazy CBs posted to CPU. */
+ unsigned long nonlazy_posted_snap;
+ /* idle-period nonlazy_posted snapshot. */
+#endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */
};
/* RCU's kthread states for tracing. */
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index 2411000d9869..5271a020887e 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -1886,8 +1886,9 @@ static void __cpuinit rcu_prepare_kthreads(int cpu)
* Because we not have RCU_FAST_NO_HZ, just check whether this CPU needs
* any flavor of RCU.
*/
-int rcu_needs_cpu(int cpu)
+int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies)
{
+ *delta_jiffies = ULONG_MAX;
return rcu_cpu_has_callbacks(cpu);
}
@@ -1962,41 +1963,6 @@ static void rcu_idle_count_callbacks_posted(void)
#define RCU_IDLE_GP_DELAY 6 /* Roughly one grace period. */
#define RCU_IDLE_LAZY_GP_DELAY (6 * HZ) /* Roughly six seconds. */
-/* Loop counter for rcu_prepare_for_idle(). */
-static DEFINE_PER_CPU(int, rcu_dyntick_drain);
-/* If rcu_dyntick_holdoff==jiffies, don't try to enter dyntick-idle mode. */
-static DEFINE_PER_CPU(unsigned long, rcu_dyntick_holdoff);
-/* Timer to awaken the CPU if it enters dyntick-idle mode with callbacks. */
-static DEFINE_PER_CPU(struct timer_list, rcu_idle_gp_timer);
-/* Scheduled expiry time for rcu_idle_gp_timer to allow reposting. */
-static DEFINE_PER_CPU(unsigned long, rcu_idle_gp_timer_expires);
-/* Enable special processing on first attempt to enter dyntick-idle mode. */
-static DEFINE_PER_CPU(bool, rcu_idle_first_pass);
-/* Running count of non-lazy callbacks posted, never decremented. */
-static DEFINE_PER_CPU(unsigned long, rcu_nonlazy_posted);
-/* Snapshot of rcu_nonlazy_posted to detect meaningful exits from idle. */
-static DEFINE_PER_CPU(unsigned long, rcu_nonlazy_posted_snap);
-
-/*
- * Allow the CPU to enter dyntick-idle mode if either: (1) There are no
- * callbacks on this CPU, (2) this CPU has not yet attempted to enter
- * dyntick-idle mode, or (3) this CPU is in the process of attempting to
- * enter dyntick-idle mode. Otherwise, if we have recently tried and failed
- * to enter dyntick-idle mode, we refuse to try to enter it. After all,
- * it is better to incur scheduling-clock interrupts than to spin
- * continuously for the same time duration!
- */
-int rcu_needs_cpu(int cpu)
-{
- /* Flag a new idle sojourn to the idle-entry state machine. */
- per_cpu(rcu_idle_first_pass, cpu) = 1;
- /* If no callbacks, RCU doesn't need the CPU. */
- if (!rcu_cpu_has_callbacks(cpu))
- return 0;
- /* Otherwise, RCU needs the CPU only if it recently tried and failed. */
- return per_cpu(rcu_dyntick_holdoff, cpu) == jiffies;
-}
-
/*
* Does the specified flavor of RCU have non-lazy callbacks pending on
* the specified CPU? Both RCU flavor and CPU are specified by the
@@ -2040,6 +2006,47 @@ static bool rcu_cpu_has_nonlazy_callbacks(int cpu)
}
/*
+ * Allow the CPU to enter dyntick-idle mode if either: (1) There are no
+ * callbacks on this CPU, (2) this CPU has not yet attempted to enter
+ * dyntick-idle mode, or (3) this CPU is in the process of attempting to
+ * enter dyntick-idle mode. Otherwise, if we have recently tried and failed
+ * to enter dyntick-idle mode, we refuse to try to enter it. After all,
+ * it is better to incur scheduling-clock interrupts than to spin
+ * continuously for the same time duration!
+ *
+ * The delta_jiffies argument is used to store the time when RCU is
+ * going to need the CPU again if it still has callbacks. The reason
+ * for this is that rcu_prepare_for_idle() might need to post a timer,
+ * but if so, it will do so after tick_nohz_stop_sched_tick() has set
+ * the wakeup time for this CPU. This means that RCU's timer can be
+ * delayed until the wakeup time, which defeats the purpose of posting
+ * a timer.
+ */
+int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies)
+{
+ struct rcu_dynticks *rdtp = &per_cpu(rcu_dynticks, cpu);
+
+ /* Flag a new idle sojourn to the idle-entry state machine. */
+ rdtp->idle_first_pass = 1;
+ /* If no callbacks, RCU doesn't need the CPU. */
+ if (!rcu_cpu_has_callbacks(cpu)) {
+ *delta_jiffies = ULONG_MAX;
+ return 0;
+ }
+ if (rdtp->dyntick_holdoff == jiffies) {
+ /* RCU recently tried and failed, so don't try again. */
+ *delta_jiffies = 1;
+ return 1;
+ }
+ /* Set up for the possibility that RCU will post a timer. */
+ if (rcu_cpu_has_nonlazy_callbacks(cpu))
+ *delta_jiffies = RCU_IDLE_GP_DELAY;
+ else
+ *delta_jiffies = RCU_IDLE_LAZY_GP_DELAY;
+ return 0;
+}
+
+/*
* Handler for smp_call_function_single(). The only point of this
* handler is to wake the CPU up, so the handler does only tracing.
*/
@@ -2075,21 +2082,24 @@ static void rcu_idle_gp_timer_func(unsigned long cpu_in)
*/
static void rcu_prepare_for_idle_init(int cpu)
{
- per_cpu(rcu_dyntick_holdoff, cpu) = jiffies - 1;
- setup_timer(&per_cpu(rcu_idle_gp_timer, cpu),
- rcu_idle_gp_timer_func, cpu);
- per_cpu(rcu_idle_gp_timer_expires, cpu) = jiffies - 1;
- per_cpu(rcu_idle_first_pass, cpu) = 1;
+ struct rcu_dynticks *rdtp = &per_cpu(rcu_dynticks, cpu);
+
+ rdtp->dyntick_holdoff = jiffies - 1;
+ setup_timer(&rdtp->idle_gp_timer, rcu_idle_gp_timer_func, cpu);
+ rdtp->idle_gp_timer_expires = jiffies - 1;
+ rdtp->idle_first_pass = 1;
}
/*
* Clean up for exit from idle. Because we are exiting from idle, there
- * is no longer any point to rcu_idle_gp_timer, so cancel it. This will
+ * is no longer any point to ->idle_gp_timer, so cancel it. This will
* do nothing if this timer is not active, so just cancel it unconditionally.
*/
static void rcu_cleanup_after_idle(int cpu)
{
- del_timer(&per_cpu(rcu_idle_gp_timer, cpu));
+ struct rcu_dynticks *rdtp = &per_cpu(rcu_dynticks, cpu);
+
+ del_timer(&rdtp->idle_gp_timer);
trace_rcu_prep_idle("Cleanup after idle");
}
@@ -2108,42 +2118,41 @@ static void rcu_cleanup_after_idle(int cpu)
* Because it is not legal to invoke rcu_process_callbacks() with irqs
* disabled, we do one pass of force_quiescent_state(), then do a
* invoke_rcu_core() to cause rcu_process_callbacks() to be invoked
- * later. The per-cpu rcu_dyntick_drain variable controls the sequencing.
+ * later. The ->dyntick_drain field controls the sequencing.
*
* The caller must have disabled interrupts.
*/
static void rcu_prepare_for_idle(int cpu)
{
struct timer_list *tp;
+ struct rcu_dynticks *rdtp = &per_cpu(rcu_dynticks, cpu);
/*
* If this is an idle re-entry, for example, due to use of
* RCU_NONIDLE() or the new idle-loop tracing API within the idle
* loop, then don't take any state-machine actions, unless the
* momentary exit from idle queued additional non-lazy callbacks.
- * Instead, repost the rcu_idle_gp_timer if this CPU has callbacks
+ * Instead, repost the ->idle_gp_timer if this CPU has callbacks
* pending.
*/
- if (!per_cpu(rcu_idle_first_pass, cpu) &&
- (per_cpu(rcu_nonlazy_posted, cpu) ==
- per_cpu(rcu_nonlazy_posted_snap, cpu))) {
+ if (!rdtp->idle_first_pass &&
+ (rdtp->nonlazy_posted == rdtp->nonlazy_posted_snap)) {
if (rcu_cpu_has_callbacks(cpu)) {
- tp = &per_cpu(rcu_idle_gp_timer, cpu);
- mod_timer_pinned(tp, per_cpu(rcu_idle_gp_timer_expires, cpu));
+ tp = &rdtp->idle_gp_timer;
+ mod_timer_pinned(tp, rdtp->idle_gp_timer_expires);
}
return;
}
- per_cpu(rcu_idle_first_pass, cpu) = 0;
- per_cpu(rcu_nonlazy_posted_snap, cpu) =
- per_cpu(rcu_nonlazy_posted, cpu) - 1;
+ rdtp->idle_first_pass = 0;
+ rdtp->nonlazy_posted_snap = rdtp->nonlazy_posted - 1;
/*
* If there are no callbacks on this CPU, enter dyntick-idle mode.
* Also reset state to avoid prejudicing later attempts.
*/
if (!rcu_cpu_has_callbacks(cpu)) {
- per_cpu(rcu_dyntick_holdoff, cpu) = jiffies - 1;
- per_cpu(rcu_dyntick_drain, cpu) = 0;
+ rdtp->dyntick_holdoff = jiffies - 1;
+ rdtp->dyntick_drain = 0;
trace_rcu_prep_idle("No callbacks");
return;
}
@@ -2152,36 +2161,37 @@ static void rcu_prepare_for_idle(int cpu)
* If in holdoff mode, just return. We will presumably have
* refrained from disabling the scheduling-clock tick.
*/
- if (per_cpu(rcu_dyntick_holdoff, cpu) == jiffies) {
+ if (rdtp->dyntick_holdoff == jiffies) {
trace_rcu_prep_idle("In holdoff");
return;
}
- /* Check and update the rcu_dyntick_drain sequencing. */
- if (per_cpu(rcu_dyntick_drain, cpu) <= 0) {
+ /* Check and update the ->dyntick_drain sequencing. */
+ if (rdtp->dyntick_drain <= 0) {
/* First time through, initialize the counter. */
- per_cpu(rcu_dyntick_drain, cpu) = RCU_IDLE_FLUSHES;
- } else if (per_cpu(rcu_dyntick_drain, cpu) <= RCU_IDLE_OPT_FLUSHES &&
+ rdtp->dyntick_drain = RCU_IDLE_FLUSHES;
+ } else if (rdtp->dyntick_drain <= RCU_IDLE_OPT_FLUSHES &&
!rcu_pending(cpu) &&
!local_softirq_pending()) {
/* Can we go dyntick-idle despite still having callbacks? */
- trace_rcu_prep_idle("Dyntick with callbacks");
- per_cpu(rcu_dyntick_drain, cpu) = 0;
- per_cpu(rcu_dyntick_holdoff, cpu) = jiffies;
- if (rcu_cpu_has_nonlazy_callbacks(cpu))
- per_cpu(rcu_idle_gp_timer_expires, cpu) =
+ rdtp->dyntick_drain = 0;
+ rdtp->dyntick_holdoff = jiffies;
+ if (rcu_cpu_has_nonlazy_callbacks(cpu)) {
+ trace_rcu_prep_idle("Dyntick with callbacks");
+ rdtp->idle_gp_timer_expires =
jiffies + RCU_IDLE_GP_DELAY;
- else
- per_cpu(rcu_idle_gp_timer_expires, cpu) =
+ } else {
+ rdtp->idle_gp_timer_expires =
jiffies + RCU_IDLE_LAZY_GP_DELAY;
- tp = &per_cpu(rcu_idle_gp_timer, cpu);
- mod_timer_pinned(tp, per_cpu(rcu_idle_gp_timer_expires, cpu));
- per_cpu(rcu_nonlazy_posted_snap, cpu) =
- per_cpu(rcu_nonlazy_posted, cpu);
+ trace_rcu_prep_idle("Dyntick with lazy callbacks");
+ }
+ tp = &rdtp->idle_gp_timer;
+ mod_timer_pinned(tp, rdtp->idle_gp_timer_expires);
+ rdtp->nonlazy_posted_snap = rdtp->nonlazy_posted;
return; /* Nothing more to do immediately. */
- } else if (--per_cpu(rcu_dyntick_drain, cpu) <= 0) {
+ } else if (--(rdtp->dyntick_drain) <= 0) {
/* We have hit the limit, so time to give up. */
- per_cpu(rcu_dyntick_holdoff, cpu) = jiffies;
+ rdtp->dyntick_holdoff = jiffies;
trace_rcu_prep_idle("Begin holdoff");
invoke_rcu_core(); /* Force the CPU out of dyntick-idle. */
return;
@@ -2227,7 +2237,7 @@ static void rcu_prepare_for_idle(int cpu)
*/
static void rcu_idle_count_callbacks_posted(void)
{
- __this_cpu_add(rcu_nonlazy_posted, 1);
+ __this_cpu_add(rcu_dynticks.nonlazy_posted, 1);
}
#endif /* #else #if !defined(CONFIG_RCU_FAST_NO_HZ) */
@@ -2238,11 +2248,12 @@ static void rcu_idle_count_callbacks_posted(void)
static void print_cpu_stall_fast_no_hz(char *cp, int cpu)
{
- struct timer_list *tltp = &per_cpu(rcu_idle_gp_timer, cpu);
+ struct rcu_dynticks *rdtp = &per_cpu(rcu_dynticks, cpu);
+ struct timer_list *tltp = &rdtp->idle_gp_timer;
sprintf(cp, "drain=%d %c timer=%lu",
- per_cpu(rcu_dyntick_drain, cpu),
- per_cpu(rcu_dyntick_holdoff, cpu) == jiffies ? 'H' : '.',
+ rdtp->dyntick_drain,
+ rdtp->dyntick_holdoff == jiffies ? 'H' : '.',
timer_pending(tltp) ? tltp->expires - jiffies : -1);
}
diff --git a/kernel/resource.c b/kernel/resource.c
index 7e8ea66a8c01..e1d2b8ee76d5 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -515,8 +515,8 @@ out:
* @root: root resource descriptor
* @new: resource descriptor desired by caller
* @size: requested resource region size
- * @min: minimum size to allocate
- * @max: maximum size to allocate
+ * @min: minimum boundary to allocate
+ * @max: maximum boundary to allocate
* @align: alignment requested, in bytes
* @alignf: alignment function, optional, called if not NULL
* @alignf_data: arbitrary data to pass to the @alignf function
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 39eb6011bc38..d5594a4268d4 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -142,9 +142,8 @@ const_debug unsigned int sysctl_sched_features =
#define SCHED_FEAT(name, enabled) \
#name ,
-static __read_mostly char *sched_feat_names[] = {
+static const char * const sched_feat_names[] = {
#include "features.h"
- NULL
};
#undef SCHED_FEAT
@@ -2517,25 +2516,32 @@ static void __update_cpu_load(struct rq *this_rq, unsigned long this_load,
sched_avg_update(this_rq);
}
+#ifdef CONFIG_NO_HZ
+/*
+ * There is no sane way to deal with nohz on smp when using jiffies because the
+ * cpu doing the jiffies update might drift wrt the cpu doing the jiffy reading
+ * causing off-by-one errors in observed deltas; {0,2} instead of {1,1}.
+ *
+ * Therefore we cannot use the delta approach from the regular tick since that
+ * would seriously skew the load calculation. However we'll make do for those
+ * updates happening while idle (nohz_idle_balance) or coming out of idle
+ * (tick_nohz_idle_exit).
+ *
+ * This means we might still be one tick off for nohz periods.
+ */
+
/*
* Called from nohz_idle_balance() to update the load ratings before doing the
* idle balance.
*/
void update_idle_cpu_load(struct rq *this_rq)
{
- unsigned long curr_jiffies = jiffies;
+ unsigned long curr_jiffies = ACCESS_ONCE(jiffies);
unsigned long load = this_rq->load.weight;
unsigned long pending_updates;
/*
- * Bloody broken means of dealing with nohz, but better than nothing..
- * jiffies is updated by one cpu, another cpu can drift wrt the jiffy
- * update and see 0 difference the one time and 2 the next, even though
- * we ticked at roughtly the same rate.
- *
- * Hence we only use this from nohz_idle_balance() and skip this
- * nonsense when called from the scheduler_tick() since that's
- * guaranteed a stable rate.
+ * bail if there's load or we're actually up-to-date.
*/
if (load || curr_jiffies == this_rq->last_load_update_tick)
return;
@@ -2547,12 +2553,38 @@ void update_idle_cpu_load(struct rq *this_rq)
}
/*
+ * Called from tick_nohz_idle_exit() -- try and fix up the ticks we missed.
+ */
+void update_cpu_load_nohz(void)
+{
+ struct rq *this_rq = this_rq();
+ unsigned long curr_jiffies = ACCESS_ONCE(jiffies);
+ unsigned long pending_updates;
+
+ if (curr_jiffies == this_rq->last_load_update_tick)
+ return;
+
+ raw_spin_lock(&this_rq->lock);
+ pending_updates = curr_jiffies - this_rq->last_load_update_tick;
+ if (pending_updates) {
+ this_rq->last_load_update_tick = curr_jiffies;
+ /*
+ * We were idle, this means load 0, the current load might be
+ * !0 due to remote wakeups and the sort.
+ */
+ __update_cpu_load(this_rq, 0, pending_updates);
+ }
+ raw_spin_unlock(&this_rq->lock);
+}
+#endif /* CONFIG_NO_HZ */
+
+/*
* Called from scheduler_tick()
*/
static void update_cpu_load_active(struct rq *this_rq)
{
/*
- * See the mess in update_idle_cpu_load().
+ * See the mess around update_idle_cpu_load() / update_cpu_load_nohz().
*/
this_rq->last_load_update_tick = jiffies;
__update_cpu_load(this_rq, this_rq->load.weight, 1);
@@ -4982,7 +5014,7 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
p->sched_class->set_cpus_allowed(p, new_mask);
cpumask_copy(&p->cpus_allowed, new_mask);
- p->rt.nr_cpus_allowed = cpumask_weight(new_mask);
+ p->nr_cpus_allowed = cpumask_weight(new_mask);
}
/*
@@ -5524,15 +5556,20 @@ static cpumask_var_t sched_domains_tmpmask; /* sched_domains_mutex */
#ifdef CONFIG_SCHED_DEBUG
-static __read_mostly int sched_domain_debug_enabled;
+static __read_mostly int sched_debug_enabled;
-static int __init sched_domain_debug_setup(char *str)
+static int __init sched_debug_setup(char *str)
{
- sched_domain_debug_enabled = 1;
+ sched_debug_enabled = 1;
return 0;
}
-early_param("sched_debug", sched_domain_debug_setup);
+early_param("sched_debug", sched_debug_setup);
+
+static inline bool sched_debug(void)
+{
+ return sched_debug_enabled;
+}
static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
struct cpumask *groupmask)
@@ -5572,7 +5609,12 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
break;
}
- if (!group->sgp->power) {
+ /*
+ * Even though we initialize ->power to something semi-sane,
+ * we leave power_orig unset. This allows us to detect if
+ * domain iteration is still funny without causing /0 traps.
+ */
+ if (!group->sgp->power_orig) {
printk(KERN_CONT "\n");
printk(KERN_ERR "ERROR: domain->cpu_power not "
"set\n");
@@ -5620,7 +5662,7 @@ static void sched_domain_debug(struct sched_domain *sd, int cpu)
{
int level = 0;
- if (!sched_domain_debug_enabled)
+ if (!sched_debug_enabled)
return;
if (!sd) {
@@ -5641,6 +5683,10 @@ static void sched_domain_debug(struct sched_domain *sd, int cpu)
}
#else /* !CONFIG_SCHED_DEBUG */
# define sched_domain_debug(sd, cpu) do { } while (0)
+static inline bool sched_debug(void)
+{
+ return false;
+}
#endif /* CONFIG_SCHED_DEBUG */
static int sd_degenerate(struct sched_domain *sd)
@@ -5962,6 +6008,44 @@ struct sched_domain_topology_level {
struct sd_data data;
};
+/*
+ * Build an iteration mask that can exclude certain CPUs from the upwards
+ * domain traversal.
+ *
+ * Asymmetric node setups can result in situations where the domain tree is of
+ * unequal depth, make sure to skip domains that already cover the entire
+ * range.
+ *
+ * In that case build_sched_domains() will have terminated the iteration early
+ * and our sibling sd spans will be empty. Domains should always include the
+ * cpu they're built on, so check that.
+ *
+ */
+static void build_group_mask(struct sched_domain *sd, struct sched_group *sg)
+{
+ const struct cpumask *span = sched_domain_span(sd);
+ struct sd_data *sdd = sd->private;
+ struct sched_domain *sibling;
+ int i;
+
+ for_each_cpu(i, span) {
+ sibling = *per_cpu_ptr(sdd->sd, i);
+ if (!cpumask_test_cpu(i, sched_domain_span(sibling)))
+ continue;
+
+ cpumask_set_cpu(i, sched_group_mask(sg));
+ }
+}
+
+/*
+ * Return the canonical balance cpu for this group, this is the first cpu
+ * of this group that's also in the iteration mask.
+ */
+int group_balance_cpu(struct sched_group *sg)
+{
+ return cpumask_first_and(sched_group_cpus(sg), sched_group_mask(sg));
+}
+
static int
build_overlap_sched_groups(struct sched_domain *sd, int cpu)
{
@@ -5980,6 +6064,12 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
if (cpumask_test_cpu(i, covered))
continue;
+ child = *per_cpu_ptr(sdd->sd, i);
+
+ /* See the comment near build_group_mask(). */
+ if (!cpumask_test_cpu(i, sched_domain_span(child)))
+ continue;
+
sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(),
GFP_KERNEL, cpu_to_node(cpu));
@@ -5987,8 +6077,6 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
goto fail;
sg_span = sched_group_cpus(sg);
-
- child = *per_cpu_ptr(sdd->sd, i);
if (child->child) {
child = child->child;
cpumask_copy(sg_span, sched_domain_span(child));
@@ -5997,10 +6085,24 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
cpumask_or(covered, covered, sg_span);
- sg->sgp = *per_cpu_ptr(sdd->sgp, cpumask_first(sg_span));
- atomic_inc(&sg->sgp->ref);
+ sg->sgp = *per_cpu_ptr(sdd->sgp, i);
+ if (atomic_inc_return(&sg->sgp->ref) == 1)
+ build_group_mask(sd, sg);
- if (cpumask_test_cpu(cpu, sg_span))
+ /*
+ * Initialize sgp->power such that even if we mess up the
+ * domains and no possible iteration will get us here, we won't
+ * die on a /0 trap.
+ */
+ sg->sgp->power = SCHED_POWER_SCALE * cpumask_weight(sg_span);
+
+ /*
+ * Make sure the first group of this domain contains the
+ * canonical balance cpu. Otherwise the sched_domain iteration
+ * breaks. See update_sg_lb_stats().
+ */
+ if ((!groups && cpumask_test_cpu(cpu, sg_span)) ||
+ group_balance_cpu(sg) == cpu)
groups = sg;
if (!first)
@@ -6074,6 +6176,7 @@ build_sched_groups(struct sched_domain *sd, int cpu)
cpumask_clear(sched_group_cpus(sg));
sg->sgp->power = 0;
+ cpumask_setall(sched_group_mask(sg));
for_each_cpu(j, span) {
if (get_group(j, sdd, NULL) != group)
@@ -6115,7 +6218,7 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd)
sg = sg->next;
} while (sg != sd->groups);
- if (cpu != group_first_cpu(sg))
+ if (cpu != group_balance_cpu(sg))
return;
update_group_power(sd, cpu);
@@ -6165,11 +6268,8 @@ int sched_domain_level_max;
static int __init setup_relax_domain_level(char *str)
{
- unsigned long val;
-
- val = simple_strtoul(str, NULL, 0);
- if (val < sched_domain_level_max)
- default_relax_domain_level = val;
+ if (kstrtoint(str, 0, &default_relax_domain_level))
+ pr_warn("Unable to set relax_domain_level\n");
return 1;
}
@@ -6279,14 +6379,13 @@ static struct sched_domain_topology_level *sched_domain_topology = default_topol
#ifdef CONFIG_NUMA
static int sched_domains_numa_levels;
-static int sched_domains_numa_scale;
static int *sched_domains_numa_distance;
static struct cpumask ***sched_domains_numa_masks;
static int sched_domains_curr_level;
static inline int sd_local_flags(int level)
{
- if (sched_domains_numa_distance[level] > REMOTE_DISTANCE)
+ if (sched_domains_numa_distance[level] > RECLAIM_DISTANCE)
return 0;
return SD_BALANCE_EXEC | SD_BALANCE_FORK | SD_WAKE_AFFINE;
@@ -6344,6 +6443,42 @@ static const struct cpumask *sd_numa_mask(int cpu)
return sched_domains_numa_masks[sched_domains_curr_level][cpu_to_node(cpu)];
}
+static void sched_numa_warn(const char *str)
+{
+ static int done = false;
+ int i,j;
+
+ if (done)
+ return;
+
+ done = true;
+
+ printk(KERN_WARNING "ERROR: %s\n\n", str);
+
+ for (i = 0; i < nr_node_ids; i++) {
+ printk(KERN_WARNING " ");
+ for (j = 0; j < nr_node_ids; j++)
+ printk(KERN_CONT "%02d ", node_distance(i,j));
+ printk(KERN_CONT "\n");
+ }
+ printk(KERN_WARNING "\n");
+}
+
+static bool find_numa_distance(int distance)
+{
+ int i;
+
+ if (distance == node_distance(0, 0))
+ return true;
+
+ for (i = 0; i < sched_domains_numa_levels; i++) {
+ if (sched_domains_numa_distance[i] == distance)
+ return true;
+ }
+
+ return false;
+}
+
static void sched_init_numa(void)
{
int next_distance, curr_distance = node_distance(0, 0);
@@ -6351,7 +6486,6 @@ static void sched_init_numa(void)
int level = 0;
int i, j, k;
- sched_domains_numa_scale = curr_distance;
sched_domains_numa_distance = kzalloc(sizeof(int) * nr_node_ids, GFP_KERNEL);
if (!sched_domains_numa_distance)
return;
@@ -6362,23 +6496,41 @@ static void sched_init_numa(void)
*
* Assumes node_distance(0,j) includes all distances in
* node_distance(i,j) in order to avoid cubic time.
- *
- * XXX: could be optimized to O(n log n) by using sort()
*/
next_distance = curr_distance;
for (i = 0; i < nr_node_ids; i++) {
for (j = 0; j < nr_node_ids; j++) {
- int distance = node_distance(0, j);
- if (distance > curr_distance &&
- (distance < next_distance ||
- next_distance == curr_distance))
- next_distance = distance;
+ for (k = 0; k < nr_node_ids; k++) {
+ int distance = node_distance(i, k);
+
+ if (distance > curr_distance &&
+ (distance < next_distance ||
+ next_distance == curr_distance))
+ next_distance = distance;
+
+ /*
+ * While not a strong assumption it would be nice to know
+ * about cases where if node A is connected to B, B is not
+ * equally connected to A.
+ */
+ if (sched_debug() && node_distance(k, i) != distance)
+ sched_numa_warn("Node-distance not symmetric");
+
+ if (sched_debug() && i && !find_numa_distance(distance))
+ sched_numa_warn("Node-0 not representative");
+ }
+ if (next_distance != curr_distance) {
+ sched_domains_numa_distance[level++] = next_distance;
+ sched_domains_numa_levels = level;
+ curr_distance = next_distance;
+ } else break;
}
- if (next_distance != curr_distance) {
- sched_domains_numa_distance[level++] = next_distance;
- sched_domains_numa_levels = level;
- curr_distance = next_distance;
- } else break;
+
+ /*
+ * In case of sched_debug() we verify the above assumption.
+ */
+ if (!sched_debug())
+ break;
}
/*
* 'level' contains the number of unique distances, excluding the
@@ -6403,7 +6555,7 @@ static void sched_init_numa(void)
return;
for (j = 0; j < nr_node_ids; j++) {
- struct cpumask *mask = kzalloc_node(cpumask_size(), GFP_KERNEL, j);
+ struct cpumask *mask = kzalloc(cpumask_size(), GFP_KERNEL);
if (!mask)
return;
@@ -6490,7 +6642,7 @@ static int __sdt_alloc(const struct cpumask *cpu_map)
*per_cpu_ptr(sdd->sg, j) = sg;
- sgp = kzalloc_node(sizeof(struct sched_group_power),
+ sgp = kzalloc_node(sizeof(struct sched_group_power) + cpumask_size(),
GFP_KERNEL, cpu_to_node(j));
if (!sgp)
return -ENOMEM;
@@ -6543,7 +6695,6 @@ struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl,
if (!sd)
return child;
- set_domain_attribute(sd, attr);
cpumask_and(sched_domain_span(sd), cpu_map, tl->mask(cpu));
if (child) {
sd->level = child->level + 1;
@@ -6551,6 +6702,7 @@ struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl,
child->parent = sd;
}
sd->child = child;
+ set_domain_attribute(sd, attr);
return sd;
}
@@ -6691,7 +6843,6 @@ static int init_sched_domains(const struct cpumask *cpu_map)
if (!doms_cur)
doms_cur = &fallback_doms;
cpumask_andnot(doms_cur[0], cpu_map, cpu_isolated_map);
- dattr_cur = NULL;
err = build_sched_domains(doms_cur[0], NULL);
register_sched_domain_sysctl();
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 940e6d17cf96..c099cc6eebe3 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2703,7 +2703,7 @@ select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flags)
int want_sd = 1;
int sync = wake_flags & WF_SYNC;
- if (p->rt.nr_cpus_allowed == 1)
+ if (p->nr_cpus_allowed == 1)
return prev_cpu;
if (sd_flag & SD_BALANCE_WAKE) {
@@ -3503,15 +3503,22 @@ unsigned long __weak arch_scale_smt_power(struct sched_domain *sd, int cpu)
unsigned long scale_rt_power(int cpu)
{
struct rq *rq = cpu_rq(cpu);
- u64 total, available;
+ u64 total, available, age_stamp, avg;
- total = sched_avg_period() + (rq->clock - rq->age_stamp);
+ /*
+ * Since we're reading these variables without serialization make sure
+ * we read them once before doing sanity checks on them.
+ */
+ age_stamp = ACCESS_ONCE(rq->age_stamp);
+ avg = ACCESS_ONCE(rq->rt_avg);
+
+ total = sched_avg_period() + (rq->clock - age_stamp);
- if (unlikely(total < rq->rt_avg)) {
+ if (unlikely(total < avg)) {
/* Ensures that power won't end up being negative */
available = 0;
} else {
- available = total - rq->rt_avg;
+ available = total - avg;
}
if (unlikely((s64)total < SCHED_POWER_SCALE))
@@ -3574,13 +3581,28 @@ void update_group_power(struct sched_domain *sd, int cpu)
power = 0;
- group = child->groups;
- do {
- power += group->sgp->power;
- group = group->next;
- } while (group != child->groups);
+ if (child->flags & SD_OVERLAP) {
+ /*
+ * SD_OVERLAP domains cannot assume that child groups
+ * span the current group.
+ */
- sdg->sgp->power = power;
+ for_each_cpu(cpu, sched_group_cpus(sdg))
+ power += power_of(cpu);
+ } else {
+ /*
+ * !SD_OVERLAP domains can assume that child groups
+ * span the current group.
+ */
+
+ group = child->groups;
+ do {
+ power += group->sgp->power;
+ group = group->next;
+ } while (group != child->groups);
+ }
+
+ sdg->sgp->power_orig = sdg->sgp->power = power;
}
/*
@@ -3610,7 +3632,7 @@ fix_small_capacity(struct sched_domain *sd, struct sched_group *group)
/**
* update_sg_lb_stats - Update sched_group's statistics for load balancing.
- * @sd: The sched_domain whose statistics are to be updated.
+ * @env: The load balancing environment.
* @group: sched_group whose statistics are to be updated.
* @load_idx: Load index of sched_domain of this_cpu for load calc.
* @local_group: Does group contain this_cpu.
@@ -3630,7 +3652,7 @@ static inline void update_sg_lb_stats(struct lb_env *env,
int i;
if (local_group)
- balance_cpu = group_first_cpu(group);
+ balance_cpu = group_balance_cpu(group);
/* Tally up the load of all CPUs in the group */
max_cpu_load = 0;
@@ -3645,7 +3667,8 @@ static inline void update_sg_lb_stats(struct lb_env *env,
/* Bias balancing toward cpus of our domain */
if (local_group) {
- if (idle_cpu(i) && !first_idle_cpu) {
+ if (idle_cpu(i) && !first_idle_cpu &&
+ cpumask_test_cpu(i, sched_group_mask(group))) {
first_idle_cpu = 1;
balance_cpu = i;
}
@@ -3719,11 +3742,10 @@ static inline void update_sg_lb_stats(struct lb_env *env,
/**
* update_sd_pick_busiest - return 1 on busiest group
- * @sd: sched_domain whose statistics are to be checked
+ * @env: The load balancing environment.
* @sds: sched_domain statistics
* @sg: sched_group candidate to be checked for being the busiest
* @sgs: sched_group statistics
- * @this_cpu: the current cpu
*
* Determine if @sg is a busier group than the previously selected
* busiest group.
@@ -3761,9 +3783,7 @@ static bool update_sd_pick_busiest(struct lb_env *env,
/**
* update_sd_lb_stats - Update sched_domain's statistics for load balancing.
- * @sd: sched_domain whose statistics are to be updated.
- * @this_cpu: Cpu for which load balance is currently performed.
- * @idle: Idle status of this_cpu
+ * @env: The load balancing environment.
* @cpus: Set of cpus considered for load balancing.
* @balance: Should we balance.
* @sds: variable to hold the statistics for this sched_domain.
@@ -3852,10 +3872,8 @@ static inline void update_sd_lb_stats(struct lb_env *env,
* Returns 1 when packing is required and a task should be moved to
* this CPU. The amount of the imbalance is returned in *imbalance.
*
- * @sd: The sched_domain whose packing is to be checked.
+ * @env: The load balancing environment.
* @sds: Statistics of the sched_domain which is to be packed
- * @this_cpu: The cpu at whose sched_domain we're performing load-balance.
- * @imbalance: returns amount of imbalanced due to packing.
*/
static int check_asym_packing(struct lb_env *env, struct sd_lb_stats *sds)
{
@@ -3881,9 +3899,8 @@ static int check_asym_packing(struct lb_env *env, struct sd_lb_stats *sds)
* fix_small_imbalance - Calculate the minor imbalance that exists
* amongst the groups of a sched_domain, during
* load balancing.
+ * @env: The load balancing environment.
* @sds: Statistics of the sched_domain whose imbalance is to be calculated.
- * @this_cpu: The cpu at whose sched_domain we're performing load-balance.
- * @imbalance: Variable to store the imbalance.
*/
static inline
void fix_small_imbalance(struct lb_env *env, struct sd_lb_stats *sds)
@@ -4026,11 +4043,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
* Also calculates the amount of weighted load which should be moved
* to restore balance.
*
- * @sd: The sched_domain whose busiest group is to be returned.
- * @this_cpu: The cpu for which load balancing is currently being performed.
- * @imbalance: Variable which stores amount of weighted load which should
- * be moved to restore balance/put a group to idle.
- * @idle: The idle status of this_cpu.
+ * @env: The load balancing environment.
* @cpus: The set of CPUs under consideration for load-balancing.
* @balance: Pointer to a variable indicating if this_cpu
* is the appropriate cpu to perform load balancing at this_level.
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index c5565c3c515f..573e1ca01102 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -274,13 +274,16 @@ static void update_rt_migration(struct rt_rq *rt_rq)
static void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
{
+ struct task_struct *p;
+
if (!rt_entity_is_task(rt_se))
return;
+ p = rt_task_of(rt_se);
rt_rq = &rq_of_rt_rq(rt_rq)->rt;
rt_rq->rt_nr_total++;
- if (rt_se->nr_cpus_allowed > 1)
+ if (p->nr_cpus_allowed > 1)
rt_rq->rt_nr_migratory++;
update_rt_migration(rt_rq);
@@ -288,13 +291,16 @@ static void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
static void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
{
+ struct task_struct *p;
+
if (!rt_entity_is_task(rt_se))
return;
+ p = rt_task_of(rt_se);
rt_rq = &rq_of_rt_rq(rt_rq)->rt;
rt_rq->rt_nr_total--;
- if (rt_se->nr_cpus_allowed > 1)
+ if (p->nr_cpus_allowed > 1)
rt_rq->rt_nr_migratory--;
update_rt_migration(rt_rq);
@@ -1161,7 +1167,7 @@ enqueue_task_rt(struct rq *rq, struct task_struct *p, int flags)
enqueue_rt_entity(rt_se, flags & ENQUEUE_HEAD);
- if (!task_current(rq, p) && p->rt.nr_cpus_allowed > 1)
+ if (!task_current(rq, p) && p->nr_cpus_allowed > 1)
enqueue_pushable_task(rq, p);
inc_nr_running(rq);
@@ -1225,7 +1231,7 @@ select_task_rq_rt(struct task_struct *p, int sd_flag, int flags)
cpu = task_cpu(p);
- if (p->rt.nr_cpus_allowed == 1)
+ if (p->nr_cpus_allowed == 1)
goto out;
/* For anything but wake ups, just return the task_cpu */
@@ -1260,9 +1266,9 @@ select_task_rq_rt(struct task_struct *p, int sd_flag, int flags)
* will have to sort it out.
*/
if (curr && unlikely(rt_task(curr)) &&
- (curr->rt.nr_cpus_allowed < 2 ||
+ (curr->nr_cpus_allowed < 2 ||
curr->prio <= p->prio) &&
- (p->rt.nr_cpus_allowed > 1)) {
+ (p->nr_cpus_allowed > 1)) {
int target = find_lowest_rq(p);
if (target != -1)
@@ -1276,10 +1282,10 @@ out:
static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p)
{
- if (rq->curr->rt.nr_cpus_allowed == 1)
+ if (rq->curr->nr_cpus_allowed == 1)
return;
- if (p->rt.nr_cpus_allowed != 1
+ if (p->nr_cpus_allowed != 1
&& cpupri_find(&rq->rd->cpupri, p, NULL))
return;
@@ -1395,7 +1401,7 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
* The previous task needs to be made eligible for pushing
* if it is still active
*/
- if (on_rt_rq(&p->rt) && p->rt.nr_cpus_allowed > 1)
+ if (on_rt_rq(&p->rt) && p->nr_cpus_allowed > 1)
enqueue_pushable_task(rq, p);
}
@@ -1408,7 +1414,7 @@ static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu)
{
if (!task_running(rq, p) &&
(cpu < 0 || cpumask_test_cpu(cpu, tsk_cpus_allowed(p))) &&
- (p->rt.nr_cpus_allowed > 1))
+ (p->nr_cpus_allowed > 1))
return 1;
return 0;
}
@@ -1464,7 +1470,7 @@ static int find_lowest_rq(struct task_struct *task)
if (unlikely(!lowest_mask))
return -1;
- if (task->rt.nr_cpus_allowed == 1)
+ if (task->nr_cpus_allowed == 1)
return -1; /* No other targets possible */
if (!cpupri_find(&task_rq(task)->rd->cpupri, task, lowest_mask))
@@ -1556,7 +1562,7 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
task_running(rq, task) ||
!task->on_rq)) {
- raw_spin_unlock(&lowest_rq->lock);
+ double_unlock_balance(rq, lowest_rq);
lowest_rq = NULL;
break;
}
@@ -1586,7 +1592,7 @@ static struct task_struct *pick_next_pushable_task(struct rq *rq)
BUG_ON(rq->cpu != task_cpu(p));
BUG_ON(task_current(rq, p));
- BUG_ON(p->rt.nr_cpus_allowed <= 1);
+ BUG_ON(p->nr_cpus_allowed <= 1);
BUG_ON(!p->on_rq);
BUG_ON(!rt_task(p));
@@ -1793,9 +1799,9 @@ static void task_woken_rt(struct rq *rq, struct task_struct *p)
if (!task_running(rq, p) &&
!test_tsk_need_resched(rq->curr) &&
has_pushable_tasks(rq) &&
- p->rt.nr_cpus_allowed > 1 &&
+ p->nr_cpus_allowed > 1 &&
rt_task(rq->curr) &&
- (rq->curr->rt.nr_cpus_allowed < 2 ||
+ (rq->curr->nr_cpus_allowed < 2 ||
rq->curr->prio <= p->prio))
push_rt_tasks(rq);
}
@@ -1817,7 +1823,7 @@ static void set_cpus_allowed_rt(struct task_struct *p,
* Only update if the process changes its state from whether it
* can migrate or not.
*/
- if ((p->rt.nr_cpus_allowed > 1) == (weight > 1))
+ if ((p->nr_cpus_allowed > 1) == (weight > 1))
return;
rq = task_rq(p);
@@ -1979,6 +1985,8 @@ static void watchdog(struct rq *rq, struct task_struct *p)
static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
{
+ struct sched_rt_entity *rt_se = &p->rt;
+
update_curr_rt(rq);
watchdog(rq, p);
@@ -1996,12 +2004,15 @@ static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
p->rt.time_slice = RR_TIMESLICE;
/*
- * Requeue to the end of queue if we are not the only element
- * on the queue:
+ * Requeue to the end of queue if we (and all of our ancestors) are the
+ * only element on the queue
*/
- if (p->rt.run_list.prev != p->rt.run_list.next) {
- requeue_task_rt(rq, p, 0);
- set_tsk_need_resched(p);
+ for_each_sched_rt_entity(rt_se) {
+ if (rt_se->run_list.prev != rt_se->run_list.next) {
+ requeue_task_rt(rq, p, 0);
+ set_tsk_need_resched(p);
+ return;
+ }
}
}
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index ba9dccfd24ce..6d52cea7f33d 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -526,6 +526,8 @@ static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
DECLARE_PER_CPU(struct sched_domain *, sd_llc);
DECLARE_PER_CPU(int, sd_llc_id);
+extern int group_balance_cpu(struct sched_group *sg);
+
#endif /* CONFIG_SMP */
#include "stats.h"
diff --git a/kernel/signal.c b/kernel/signal.c
index f7b418217633..677102789cf2 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1656,19 +1656,18 @@ bool do_notify_parent(struct task_struct *tsk, int sig)
info.si_signo = sig;
info.si_errno = 0;
/*
- * we are under tasklist_lock here so our parent is tied to
- * us and cannot exit and release its namespace.
+ * We are under tasklist_lock here so our parent is tied to
+ * us and cannot change.
*
- * the only it can is to switch its nsproxy with sys_unshare,
- * bu uncharing pid namespaces is not allowed, so we'll always
- * see relevant namespace
+ * task_active_pid_ns will always return the same pid namespace
+ * until a task passes through release_task.
*
* write_lock() currently calls preempt_disable() which is the
* same as rcu_read_lock(), but according to Oleg, this is not
* correct to rely on this
*/
rcu_read_lock();
- info.si_pid = task_pid_nr_ns(tsk, tsk->parent->nsproxy->pid_ns);
+ info.si_pid = task_pid_nr_ns(tsk, task_active_pid_ns(tsk->parent));
info.si_uid = from_kuid_munged(task_cred_xxx(tsk->parent, user_ns),
task_uid(tsk));
rcu_read_unlock();
@@ -2369,24 +2368,34 @@ relock:
}
/**
- * block_sigmask - add @ka's signal mask to current->blocked
- * @ka: action for @signr
- * @signr: signal that has been successfully delivered
+ * signal_delivered -
+ * @sig: number of signal being delivered
+ * @info: siginfo_t of signal being delivered
+ * @ka: sigaction setting that chose the handler
+ * @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
- * delivered. It adds the mask of signals for @ka to current->blocked
- * so that they are blocked during the execution of the signal
- * handler. In addition, @signr will be blocked unless %SA_NODEFER is
- * set in @ka->sa.sa_flags.
+ * 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.
*/
-void block_sigmask(struct k_sigaction *ka, int signr)
+void signal_delivered(int sig, siginfo_t *info, struct k_sigaction *ka,
+ struct pt_regs *regs, int stepping)
{
sigset_t blocked;
+ /* A signal was successfully delivered, and the
+ saved sigmask was stored on the signal frame,
+ and will be restored by sigreturn. So we can
+ simply clear the restore sigmask flag. */
+ clear_restore_sigmask();
+
sigorsets(&blocked, &current->blocked, &ka->sa.sa_mask);
if (!(ka->sa.sa_flags & SA_NODEFER))
- sigaddset(&blocked, signr);
+ sigaddset(&blocked, sig);
set_current_blocked(&blocked);
+ tracehook_signal_handler(sig, info, ka, regs, stepping);
}
/*
@@ -2519,7 +2528,16 @@ static void __set_task_blocked(struct task_struct *tsk, const sigset_t *newset)
* It is wrong to change ->blocked directly, this helper should be used
* to ensure the process can't miss a shared signal we are going to block.
*/
-void set_current_blocked(const sigset_t *newset)
+void set_current_blocked(sigset_t *newset)
+{
+ struct task_struct *tsk = current;
+ sigdelsetmask(newset, sigmask(SIGKILL) | sigmask(SIGSTOP));
+ spin_lock_irq(&tsk->sighand->siglock);
+ __set_task_blocked(tsk, newset);
+ spin_unlock_irq(&tsk->sighand->siglock);
+}
+
+void __set_current_blocked(const sigset_t *newset)
{
struct task_struct *tsk = current;
@@ -2559,7 +2577,7 @@ int sigprocmask(int how, sigset_t *set, sigset_t *oldset)
return -EINVAL;
}
- set_current_blocked(&newset);
+ __set_current_blocked(&newset);
return 0;
}
@@ -3133,7 +3151,7 @@ SYSCALL_DEFINE3(sigprocmask, int, how, old_sigset_t __user *, nset,
return -EINVAL;
}
- set_current_blocked(&new_blocked);
+ __set_current_blocked(&new_blocked);
}
if (oset) {
@@ -3197,7 +3215,6 @@ SYSCALL_DEFINE1(ssetmask, int, newmask)
int old = current->blocked.sig[0];
sigset_t newset;
- siginitset(&newset, newmask & ~(sigmask(SIGKILL) | sigmask(SIGSTOP)));
set_current_blocked(&newset);
return old;
@@ -3236,11 +3253,8 @@ SYSCALL_DEFINE0(pause)
#endif
-#ifdef HAVE_SET_RESTORE_SIGMASK
int sigsuspend(sigset_t *set)
{
- sigdelsetmask(set, sigmask(SIGKILL)|sigmask(SIGSTOP));
-
current->saved_sigmask = current->blocked;
set_current_blocked(set);
@@ -3249,7 +3263,6 @@ int sigsuspend(sigset_t *set)
set_restore_sigmask();
return -ERESTARTNOHAND;
}
-#endif
#ifdef __ARCH_WANT_SYS_RT_SIGSUSPEND
/**
diff --git a/kernel/smpboot.c b/kernel/smpboot.c
index e1a797e028a3..98f60c5caa1b 100644
--- a/kernel/smpboot.c
+++ b/kernel/smpboot.c
@@ -31,6 +31,12 @@ void __init idle_thread_set_boot_cpu(void)
per_cpu(idle_threads, smp_processor_id()) = current;
}
+/**
+ * idle_init - Initialize the idle thread for a cpu
+ * @cpu: The cpu for which the idle thread should be initialized
+ *
+ * Creates the thread if it does not exist.
+ */
static inline void idle_init(unsigned int cpu)
{
struct task_struct *tsk = per_cpu(idle_threads, cpu);
@@ -45,17 +51,16 @@ static inline void idle_init(unsigned int cpu)
}
/**
- * idle_thread_init - Initialize the idle thread for a cpu
- * @cpu: The cpu for which the idle thread should be initialized
- *
- * Creates the thread if it does not exist.
+ * idle_threads_init - Initialize idle threads for all cpus
*/
void __init idle_threads_init(void)
{
- unsigned int cpu;
+ unsigned int cpu, boot_cpu;
+
+ boot_cpu = smp_processor_id();
for_each_possible_cpu(cpu) {
- if (cpu != smp_processor_id())
+ if (cpu != boot_cpu)
idle_init(cpu);
}
}
diff --git a/kernel/sys.c b/kernel/sys.c
index 6df42624e454..e0c8ffc50d7f 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -36,6 +36,8 @@
#include <linux/personality.h>
#include <linux/ptrace.h>
#include <linux/fs_struct.h>
+#include <linux/file.h>
+#include <linux/mount.h>
#include <linux/gfp.h>
#include <linux/syscore_ops.h>
#include <linux/version.h>
@@ -1378,8 +1380,8 @@ SYSCALL_DEFINE2(sethostname, char __user *, name, int, len)
memcpy(u->nodename, tmp, len);
memset(u->nodename + len, 0, sizeof(u->nodename) - len);
errno = 0;
+ uts_proc_notify(UTS_PROC_HOSTNAME);
}
- uts_proc_notify(UTS_PROC_HOSTNAME);
up_write(&uts_sem);
return errno;
}
@@ -1429,8 +1431,8 @@ SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len)
memcpy(u->domainname, tmp, len);
memset(u->domainname + len, 0, sizeof(u->domainname) - len);
errno = 0;
+ uts_proc_notify(UTS_PROC_DOMAINNAME);
}
- uts_proc_notify(UTS_PROC_DOMAINNAME);
up_write(&uts_sem);
return errno;
}
@@ -1784,77 +1786,101 @@ SYSCALL_DEFINE1(umask, int, mask)
}
#ifdef CONFIG_CHECKPOINT_RESTORE
+static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
+{
+ struct vm_area_struct *vma;
+ struct file *exe_file;
+ struct dentry *dentry;
+ int err;
+
+ exe_file = fget(fd);
+ if (!exe_file)
+ return -EBADF;
+
+ dentry = exe_file->f_path.dentry;
+
+ /*
+ * Because the original mm->exe_file points to executable file, make
+ * sure that this one is executable as well, to avoid breaking an
+ * overall picture.
+ */
+ err = -EACCES;
+ if (!S_ISREG(dentry->d_inode->i_mode) ||
+ exe_file->f_path.mnt->mnt_flags & MNT_NOEXEC)
+ goto exit;
+
+ err = inode_permission(dentry->d_inode, MAY_EXEC);
+ if (err)
+ goto exit;
+
+ down_write(&mm->mmap_sem);
+
+ /*
+ * Forbid mm->exe_file change if there are mapped other files.
+ */
+ err = -EBUSY;
+ for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ if (vma->vm_file && !path_equal(&vma->vm_file->f_path,
+ &exe_file->f_path))
+ goto exit_unlock;
+ }
+
+ /*
+ * The symlink can be changed only once, just to disallow arbitrary
+ * transitions malicious software might bring in. This means one
+ * could make a snapshot over all processes running and monitor
+ * /proc/pid/exe changes to notice unusual activity if needed.
+ */
+ err = -EPERM;
+ if (test_and_set_bit(MMF_EXE_FILE_CHANGED, &mm->flags))
+ goto exit_unlock;
+
+ set_mm_exe_file(mm, exe_file);
+exit_unlock:
+ up_write(&mm->mmap_sem);
+
+exit:
+ fput(exe_file);
+ return err;
+}
+
static int prctl_set_mm(int opt, unsigned long addr,
unsigned long arg4, unsigned long arg5)
{
unsigned long rlim = rlimit(RLIMIT_DATA);
- unsigned long vm_req_flags;
- unsigned long vm_bad_flags;
- struct vm_area_struct *vma;
- int error = 0;
struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ int error;
- if (arg4 | arg5)
+ if (arg5 || (arg4 && opt != PR_SET_MM_AUXV))
return -EINVAL;
if (!capable(CAP_SYS_RESOURCE))
return -EPERM;
- if (addr >= TASK_SIZE)
+ if (opt == PR_SET_MM_EXE_FILE)
+ return prctl_set_mm_exe_file(mm, (unsigned int)addr);
+
+ if (addr >= TASK_SIZE || addr < mmap_min_addr)
return -EINVAL;
+ error = -EINVAL;
+
down_read(&mm->mmap_sem);
vma = find_vma(mm, addr);
- if (opt != PR_SET_MM_START_BRK && opt != PR_SET_MM_BRK) {
- /* It must be existing VMA */
- if (!vma || vma->vm_start > addr)
- goto out;
- }
-
- error = -EINVAL;
switch (opt) {
case PR_SET_MM_START_CODE:
+ mm->start_code = addr;
+ break;
case PR_SET_MM_END_CODE:
- vm_req_flags = VM_READ | VM_EXEC;
- vm_bad_flags = VM_WRITE | VM_MAYSHARE;
-
- if ((vma->vm_flags & vm_req_flags) != vm_req_flags ||
- (vma->vm_flags & vm_bad_flags))
- goto out;
-
- if (opt == PR_SET_MM_START_CODE)
- mm->start_code = addr;
- else
- mm->end_code = addr;
+ mm->end_code = addr;
break;
-
case PR_SET_MM_START_DATA:
- case PR_SET_MM_END_DATA:
- vm_req_flags = VM_READ | VM_WRITE;
- vm_bad_flags = VM_EXEC | VM_MAYSHARE;
-
- if ((vma->vm_flags & vm_req_flags) != vm_req_flags ||
- (vma->vm_flags & vm_bad_flags))
- goto out;
-
- if (opt == PR_SET_MM_START_DATA)
- mm->start_data = addr;
- else
- mm->end_data = addr;
+ mm->start_data = addr;
break;
-
- case PR_SET_MM_START_STACK:
-
-#ifdef CONFIG_STACK_GROWSUP
- vm_req_flags = VM_READ | VM_WRITE | VM_GROWSUP;
-#else
- vm_req_flags = VM_READ | VM_WRITE | VM_GROWSDOWN;
-#endif
- if ((vma->vm_flags & vm_req_flags) != vm_req_flags)
- goto out;
-
- mm->start_stack = addr;
+ case PR_SET_MM_END_DATA:
+ mm->end_data = addr;
break;
case PR_SET_MM_START_BRK:
@@ -1881,24 +1907,89 @@ static int prctl_set_mm(int opt, unsigned long addr,
mm->brk = addr;
break;
+ /*
+ * If command line arguments and environment
+ * are placed somewhere else on stack, we can
+ * set them up here, ARG_START/END to setup
+ * command line argumets and ENV_START/END
+ * for environment.
+ */
+ case PR_SET_MM_START_STACK:
+ case PR_SET_MM_ARG_START:
+ case PR_SET_MM_ARG_END:
+ case PR_SET_MM_ENV_START:
+ case PR_SET_MM_ENV_END:
+ if (!vma) {
+ error = -EFAULT;
+ goto out;
+ }
+ if (opt == PR_SET_MM_START_STACK)
+ mm->start_stack = addr;
+ else if (opt == PR_SET_MM_ARG_START)
+ mm->arg_start = addr;
+ else if (opt == PR_SET_MM_ARG_END)
+ mm->arg_end = addr;
+ else if (opt == PR_SET_MM_ENV_START)
+ mm->env_start = addr;
+ else if (opt == PR_SET_MM_ENV_END)
+ mm->env_end = addr;
+ break;
+
+ /*
+ * This doesn't move auxiliary vector itself
+ * since it's pinned to mm_struct, but allow
+ * to fill vector with new values. It's up
+ * to a caller to provide sane values here
+ * otherwise user space tools which use this
+ * vector might be unhappy.
+ */
+ case PR_SET_MM_AUXV: {
+ unsigned long user_auxv[AT_VECTOR_SIZE];
+
+ if (arg4 > sizeof(user_auxv))
+ goto out;
+ up_read(&mm->mmap_sem);
+
+ if (copy_from_user(user_auxv, (const void __user *)addr, arg4))
+ return -EFAULT;
+
+ /* Make sure the last entry is always AT_NULL */
+ user_auxv[AT_VECTOR_SIZE - 2] = 0;
+ user_auxv[AT_VECTOR_SIZE - 1] = 0;
+
+ BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv));
+
+ task_lock(current);
+ memcpy(mm->saved_auxv, user_auxv, arg4);
+ task_unlock(current);
+
+ return 0;
+ }
default:
- error = -EINVAL;
goto out;
}
error = 0;
-
out:
up_read(&mm->mmap_sem);
-
return error;
}
+
+static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr)
+{
+ return put_user(me->clear_child_tid, tid_addr);
+}
+
#else /* CONFIG_CHECKPOINT_RESTORE */
static int prctl_set_mm(int opt, unsigned long addr,
unsigned long arg4, unsigned long arg5)
{
return -EINVAL;
}
+static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr)
+{
+ return -EINVAL;
+}
#endif
SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
@@ -2053,6 +2144,9 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
case PR_SET_MM:
error = prctl_set_mm(arg2, arg3, arg4, arg5);
break;
+ case PR_GET_TID_ADDRESS:
+ error = prctl_get_tid_address(me, (int __user **)arg2);
+ break;
case PR_SET_CHILD_SUBREAPER:
me->signal->is_child_subreaper = !!arg2;
error = 0;
@@ -2114,7 +2208,6 @@ int orderly_poweroff(bool force)
NULL
};
int ret = -ENOMEM;
- struct subprocess_info *info;
if (argv == NULL) {
printk(KERN_WARNING "%s failed to allocate memory for \"%s\"\n",
@@ -2122,18 +2215,16 @@ int orderly_poweroff(bool force)
goto out;
}
- info = call_usermodehelper_setup(argv[0], argv, envp, GFP_ATOMIC);
- if (info == NULL) {
- argv_free(argv);
- goto out;
- }
-
- call_usermodehelper_setfns(info, NULL, argv_cleanup, NULL);
+ ret = call_usermodehelper_fns(argv[0], argv, envp, UMH_NO_WAIT,
+ NULL, argv_cleanup, NULL);
+out:
+ if (likely(!ret))
+ return 0;
- ret = call_usermodehelper_exec(info, UMH_NO_WAIT);
+ if (ret == -ENOMEM)
+ argv_free(argv);
- out:
- if (ret && force) {
+ if (force) {
printk(KERN_WARNING "Failed to start orderly shutdown: "
"forcing the issue\n");
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index 47bfa16430d7..dbff751e4086 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -203,3 +203,6 @@ cond_syscall(sys_fanotify_mark);
cond_syscall(sys_name_to_handle_at);
cond_syscall(sys_open_by_handle_at);
cond_syscall(compat_sys_open_by_handle_at);
+
+/* compare kernel pointers */
+cond_syscall(sys_kcmp);
diff --git a/kernel/task_work.c b/kernel/task_work.c
new file mode 100644
index 000000000000..82d1c794066d
--- /dev/null
+++ b/kernel/task_work.c
@@ -0,0 +1,84 @@
+#include <linux/spinlock.h>
+#include <linux/task_work.h>
+#include <linux/tracehook.h>
+
+int
+task_work_add(struct task_struct *task, struct task_work *twork, bool notify)
+{
+ unsigned long flags;
+ int err = -ESRCH;
+
+#ifndef TIF_NOTIFY_RESUME
+ if (notify)
+ return -ENOTSUPP;
+#endif
+ /*
+ * We must not insert the new work if the task has already passed
+ * exit_task_work(). We rely on do_exit()->raw_spin_unlock_wait()
+ * and check PF_EXITING under pi_lock.
+ */
+ raw_spin_lock_irqsave(&task->pi_lock, flags);
+ if (likely(!(task->flags & PF_EXITING))) {
+ hlist_add_head(&twork->hlist, &task->task_works);
+ err = 0;
+ }
+ raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+
+ /* test_and_set_bit() implies mb(), see tracehook_notify_resume(). */
+ if (likely(!err) && notify)
+ set_notify_resume(task);
+ return err;
+}
+
+struct task_work *
+task_work_cancel(struct task_struct *task, task_work_func_t func)
+{
+ unsigned long flags;
+ struct task_work *twork;
+ struct hlist_node *pos;
+
+ raw_spin_lock_irqsave(&task->pi_lock, flags);
+ hlist_for_each_entry(twork, pos, &task->task_works, hlist) {
+ if (twork->func == func) {
+ hlist_del(&twork->hlist);
+ goto found;
+ }
+ }
+ twork = NULL;
+ found:
+ raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+
+ return twork;
+}
+
+void task_work_run(void)
+{
+ struct task_struct *task = current;
+ struct hlist_head task_works;
+ struct hlist_node *pos;
+
+ raw_spin_lock_irq(&task->pi_lock);
+ hlist_move_list(&task->task_works, &task_works);
+ raw_spin_unlock_irq(&task->pi_lock);
+
+ if (unlikely(hlist_empty(&task_works)))
+ return;
+ /*
+ * We use hlist to save the space in task_struct, but we want fifo.
+ * Find the last entry, the list should be short, then process them
+ * in reverse order.
+ */
+ for (pos = task_works.first; pos->next; pos = pos->next)
+ ;
+
+ for (;;) {
+ struct hlist_node **pprev = pos->pprev;
+ struct task_work *twork = container_of(pos, struct task_work,
+ hlist);
+ twork->func(twork);
+
+ if (pprev == &task_works.first)
+ break;
+ pos = container_of(pprev, struct hlist_node, next);
+ }
+}
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index 9cd928f7a7c6..7e1ce012a851 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -297,8 +297,7 @@ void clockevents_register_device(struct clock_event_device *dev)
}
EXPORT_SYMBOL_GPL(clockevents_register_device);
-static void clockevents_config(struct clock_event_device *dev,
- u32 freq)
+void clockevents_config(struct clock_event_device *dev, u32 freq)
{
u64 sec;
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 6a3a5b9ff561..869997833928 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -274,6 +274,7 @@ EXPORT_SYMBOL_GPL(get_cpu_iowait_time_us);
static void tick_nohz_stop_sched_tick(struct tick_sched *ts)
{
unsigned long seq, last_jiffies, next_jiffies, delta_jiffies;
+ unsigned long rcu_delta_jiffies;
ktime_t last_update, expires, now;
struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev;
u64 time_delta;
@@ -322,7 +323,7 @@ static void tick_nohz_stop_sched_tick(struct tick_sched *ts)
time_delta = timekeeping_max_deferment();
} while (read_seqretry(&xtime_lock, seq));
- if (rcu_needs_cpu(cpu) || printk_needs_cpu(cpu) ||
+ if (rcu_needs_cpu(cpu, &rcu_delta_jiffies) || printk_needs_cpu(cpu) ||
arch_needs_cpu(cpu)) {
next_jiffies = last_jiffies + 1;
delta_jiffies = 1;
@@ -330,6 +331,10 @@ static void tick_nohz_stop_sched_tick(struct tick_sched *ts)
/* Get the next timer wheel timer */
next_jiffies = get_next_timer_interrupt(last_jiffies);
delta_jiffies = next_jiffies - last_jiffies;
+ if (rcu_delta_jiffies < delta_jiffies) {
+ next_jiffies = last_jiffies + rcu_delta_jiffies;
+ delta_jiffies = rcu_delta_jiffies;
+ }
}
/*
* Do not stop the tick, if we are only one off
@@ -576,6 +581,7 @@ void tick_nohz_idle_exit(void)
/* Update jiffies first */
select_nohz_load_balancer(0);
tick_do_update_jiffies64(now);
+ update_cpu_load_nohz();
#ifndef CONFIG_VIRT_CPU_ACCOUNTING
/*
@@ -814,6 +820,16 @@ static enum hrtimer_restart tick_sched_timer(struct hrtimer *timer)
return HRTIMER_RESTART;
}
+static int sched_skew_tick;
+
+static int __init skew_tick(char *str)
+{
+ get_option(&str, &sched_skew_tick);
+
+ return 0;
+}
+early_param("skew_tick", skew_tick);
+
/**
* tick_setup_sched_timer - setup the tick emulation timer
*/
@@ -831,6 +847,14 @@ void tick_setup_sched_timer(void)
/* Get the next period (per cpu) */
hrtimer_set_expires(&ts->sched_timer, tick_init_jiffy_update());
+ /* Offset the tick to avert xtime_lock contention. */
+ if (sched_skew_tick) {
+ u64 offset = ktime_to_ns(tick_period) >> 1;
+ do_div(offset, num_possible_cpus());
+ offset *= smp_processor_id();
+ hrtimer_add_expires_ns(&ts->sched_timer, offset);
+ }
+
for (;;) {
hrtimer_forward(&ts->sched_timer, now, tick_period);
hrtimer_start_expires(&ts->sched_timer,
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 6e46cacf5969..6f46a00a1e8a 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -962,6 +962,7 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
timekeeper.xtime.tv_sec++;
leap = second_overflow(timekeeper.xtime.tv_sec);
timekeeper.xtime.tv_sec += leap;
+ timekeeper.wall_to_monotonic.tv_sec -= leap;
}
/* Accumulate raw time */
@@ -1077,6 +1078,7 @@ static void update_wall_time(void)
timekeeper.xtime.tv_sec++;
leap = second_overflow(timekeeper.xtime.tv_sec);
timekeeper.xtime.tv_sec += leap;
+ timekeeper.wall_to_monotonic.tv_sec -= leap;
}
timekeeping_update(false);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 68032c6177db..49249c28690d 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -371,7 +371,7 @@ EXPORT_SYMBOL_GPL(tracing_on);
void tracing_off(void)
{
if (global_trace.buffer)
- ring_buffer_record_on(global_trace.buffer);
+ ring_buffer_record_off(global_trace.buffer);
/*
* This flag is only looked at when buffers haven't been
* allocated yet. We don't really care about the race
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index e5e1d85b8c7c..4b1dfba70f7c 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -372,6 +372,13 @@ static int watchdog(void *unused)
#ifdef CONFIG_HARDLOCKUP_DETECTOR
+/*
+ * People like the simple clean cpu node info on boot.
+ * Reduce the watchdog noise by only printing messages
+ * that are different from what cpu0 displayed.
+ */
+static unsigned long cpu0_err;
+
static int watchdog_nmi_enable(int cpu)
{
struct perf_event_attr *wd_attr;
@@ -390,11 +397,21 @@ static int watchdog_nmi_enable(int cpu)
/* Try to register using hardware perf events */
event = perf_event_create_kernel_counter(wd_attr, cpu, NULL, watchdog_overflow_callback, NULL);
+
+ /* save cpu0 error for future comparision */
+ if (cpu == 0 && IS_ERR(event))
+ cpu0_err = PTR_ERR(event);
+
if (!IS_ERR(event)) {
- pr_info("enabled, takes one hw-pmu counter.\n");
+ /* only print for cpu0 or different than cpu0 */
+ if (cpu == 0 || cpu0_err)
+ pr_info("enabled on all CPUs, permanently consumes one hw-PMU counter.\n");
goto out_save;
}
+ /* skip displaying the same error again */
+ if (cpu > 0 && (PTR_ERR(event) == cpu0_err))
+ return PTR_ERR(event);
/* vary the KERN level based on the returned errno */
if (PTR_ERR(event) == -EOPNOTSUPP)