rcu: Move RCU-related source code to kernel/rcu directory

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 500 insertions, 0 deletions

diff --git a/kernel/rcu/tree_trace.c b/kernel/rcu/tree_trace.c
new file mode 100644
index 000000000000..3596797b7e46
--- /dev/null
+++ b/kernel/rcu/tree_trace.c
@@ -0,0 +1,500 @@
+/*
+ * Read-Copy Update tracing for classic implementation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright IBM Corporation, 2008
+ *
+ * Papers:  http://www.rdrop.com/users/paulmck/RCU
+ *
+ * For detailed explanation of Read-Copy Update mechanism see -
+ *		Documentation/RCU
+ *
+ */
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/smp.h>
+#include <linux/rcupdate.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/atomic.h>
+#include <linux/bitops.h>
+#include <linux/module.h>
+#include <linux/completion.h>
+#include <linux/moduleparam.h>
+#include <linux/percpu.h>
+#include <linux/notifier.h>
+#include <linux/cpu.h>
+#include <linux/mutex.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+#define RCU_TREE_NONCORE
+#include "tree.h"
+
+static int r_open(struct inode *inode, struct file *file,
+					const struct seq_operations *op)
+{
+	int ret = seq_open(file, op);
+	if (!ret) {
+		struct seq_file *m = (struct seq_file *)file->private_data;
+		m->private = inode->i_private;
+	}
+	return ret;
+}
+
+static void *r_start(struct seq_file *m, loff_t *pos)
+{
+	struct rcu_state *rsp = (struct rcu_state *)m->private;
+	*pos = cpumask_next(*pos - 1, cpu_possible_mask);
+	if ((*pos) < nr_cpu_ids)
+		return per_cpu_ptr(rsp->rda, *pos);
+	return NULL;
+}
+
+static void *r_next(struct seq_file *m, void *v, loff_t *pos)
+{
+	(*pos)++;
+	return r_start(m, pos);
+}
+
+static void r_stop(struct seq_file *m, void *v)
+{
+}
+
+static int show_rcubarrier(struct seq_file *m, void *v)
+{
+	struct rcu_state *rsp = (struct rcu_state *)m->private;
+	seq_printf(m, "bcc: %d nbd: %lu\n",
+		   atomic_read(&rsp->barrier_cpu_count),
+		   rsp->n_barrier_done);
+	return 0;
+}
+
+static int rcubarrier_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, show_rcubarrier, inode->i_private);
+}
+
+static const struct file_operations rcubarrier_fops = {
+	.owner = THIS_MODULE,
+	.open = rcubarrier_open,
+	.read = seq_read,
+	.llseek = no_llseek,
+	.release = single_release,
+};
+
+#ifdef CONFIG_RCU_BOOST
+
+static char convert_kthread_status(unsigned int kthread_status)
+{
+	if (kthread_status > RCU_KTHREAD_MAX)
+		return '?';
+	return "SRWOY"[kthread_status];
+}
+
+#endif /* #ifdef CONFIG_RCU_BOOST */
+
+static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp)
+{
+	long ql, qll;
+
+	if (!rdp->beenonline)
+		return;
+	seq_printf(m, "%3d%cc=%ld g=%ld pq=%d qp=%d",
+		   rdp->cpu,
+		   cpu_is_offline(rdp->cpu) ? '!' : ' ',
+		   ulong2long(rdp->completed), ulong2long(rdp->gpnum),
+		   rdp->passed_quiesce, rdp->qs_pending);
+	seq_printf(m, " dt=%d/%llx/%d df=%lu",
+		   atomic_read(&rdp->dynticks->dynticks),
+		   rdp->dynticks->dynticks_nesting,
+		   rdp->dynticks->dynticks_nmi_nesting,
+		   rdp->dynticks_fqs);
+	seq_printf(m, " of=%lu", rdp->offline_fqs);
+	rcu_nocb_q_lengths(rdp, &ql, &qll);
+	qll += rdp->qlen_lazy;
+	ql += rdp->qlen;
+	seq_printf(m, " ql=%ld/%ld qs=%c%c%c%c",
+		   qll, ql,
+		   ".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] !=
+			rdp->nxttail[RCU_NEXT_TAIL]],
+		   ".R"[rdp->nxttail[RCU_WAIT_TAIL] !=
+			rdp->nxttail[RCU_NEXT_READY_TAIL]],
+		   ".W"[rdp->nxttail[RCU_DONE_TAIL] !=
+			rdp->nxttail[RCU_WAIT_TAIL]],
+		   ".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]]);
+#ifdef CONFIG_RCU_BOOST
+	seq_printf(m, " kt=%d/%c ktl=%x",
+		   per_cpu(rcu_cpu_has_work, rdp->cpu),
+		   convert_kthread_status(per_cpu(rcu_cpu_kthread_status,
+					  rdp->cpu)),
+		   per_cpu(rcu_cpu_kthread_loops, rdp->cpu) & 0xffff);
+#endif /* #ifdef CONFIG_RCU_BOOST */
+	seq_printf(m, " b=%ld", rdp->blimit);
+	seq_printf(m, " ci=%lu nci=%lu co=%lu ca=%lu\n",
+		   rdp->n_cbs_invoked, rdp->n_nocbs_invoked,
+		   rdp->n_cbs_orphaned, rdp->n_cbs_adopted);
+}
+
+static int show_rcudata(struct seq_file *m, void *v)
+{
+	print_one_rcu_data(m, (struct rcu_data *)v);
+	return 0;
+}
+
+static const struct seq_operations rcudate_op = {
+	.start = r_start,
+	.next  = r_next,
+	.stop  = r_stop,
+	.show  = show_rcudata,
+};
+
+static int rcudata_open(struct inode *inode, struct file *file)
+{
+	return r_open(inode, file, &rcudate_op);
+}
+
+static const struct file_operations rcudata_fops = {
+	.owner = THIS_MODULE,
+	.open = rcudata_open,
+	.read = seq_read,
+	.llseek = no_llseek,
+	.release = seq_release,
+};
+
+static int show_rcuexp(struct seq_file *m, void *v)
+{
+	struct rcu_state *rsp = (struct rcu_state *)m->private;
+
+	seq_printf(m, "s=%lu d=%lu w=%lu tf=%lu wd1=%lu wd2=%lu n=%lu sc=%lu dt=%lu dl=%lu dx=%lu\n",
+		   atomic_long_read(&rsp->expedited_start),
+		   atomic_long_read(&rsp->expedited_done),
+		   atomic_long_read(&rsp->expedited_wrap),
+		   atomic_long_read(&rsp->expedited_tryfail),
+		   atomic_long_read(&rsp->expedited_workdone1),
+		   atomic_long_read(&rsp->expedited_workdone2),
+		   atomic_long_read(&rsp->expedited_normal),
+		   atomic_long_read(&rsp->expedited_stoppedcpus),
+		   atomic_long_read(&rsp->expedited_done_tries),
+		   atomic_long_read(&rsp->expedited_done_lost),
+		   atomic_long_read(&rsp->expedited_done_exit));
+	return 0;
+}
+
+static int rcuexp_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, show_rcuexp, inode->i_private);
+}
+
+static const struct file_operations rcuexp_fops = {
+	.owner = THIS_MODULE,
+	.open = rcuexp_open,
+	.read = seq_read,
+	.llseek = no_llseek,
+	.release = single_release,
+};
+
+#ifdef CONFIG_RCU_BOOST
+
+static void print_one_rcu_node_boost(struct seq_file *m, struct rcu_node *rnp)
+{
+	seq_printf(m, "%d:%d tasks=%c%c%c%c kt=%c ntb=%lu neb=%lu nnb=%lu ",
+		   rnp->grplo, rnp->grphi,
+		   "T."[list_empty(&rnp->blkd_tasks)],
+		   "N."[!rnp->gp_tasks],
+		   "E."[!rnp->exp_tasks],
+		   "B."[!rnp->boost_tasks],
+		   convert_kthread_status(rnp->boost_kthread_status),
+		   rnp->n_tasks_boosted, rnp->n_exp_boosts,
+		   rnp->n_normal_boosts);
+	seq_printf(m, "j=%04x bt=%04x\n",
+		   (int)(jiffies & 0xffff),
+		   (int)(rnp->boost_time & 0xffff));
+	seq_printf(m, "    balk: nt=%lu egt=%lu bt=%lu nb=%lu ny=%lu nos=%lu\n",
+		   rnp->n_balk_blkd_tasks,
+		   rnp->n_balk_exp_gp_tasks,
+		   rnp->n_balk_boost_tasks,
+		   rnp->n_balk_notblocked,
+		   rnp->n_balk_notyet,
+		   rnp->n_balk_nos);
+}
+
+static int show_rcu_node_boost(struct seq_file *m, void *unused)
+{
+	struct rcu_node *rnp;
+
+	rcu_for_each_leaf_node(&rcu_preempt_state, rnp)
+		print_one_rcu_node_boost(m, rnp);
+	return 0;
+}
+
+static int rcu_node_boost_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, show_rcu_node_boost, NULL);
+}
+
+static const struct file_operations rcu_node_boost_fops = {
+	.owner = THIS_MODULE,
+	.open = rcu_node_boost_open,
+	.read = seq_read,
+	.llseek = no_llseek,
+	.release = single_release,
+};
+
+#endif /* #ifdef CONFIG_RCU_BOOST */
+
+static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp)
+{
+	unsigned long gpnum;
+	int level = 0;
+	struct rcu_node *rnp;
+
+	gpnum = rsp->gpnum;
+	seq_printf(m, "c=%ld g=%ld s=%d jfq=%ld j=%x ",
+		   ulong2long(rsp->completed), ulong2long(gpnum),
+		   rsp->fqs_state,
+		   (long)(rsp->jiffies_force_qs - jiffies),
+		   (int)(jiffies & 0xffff));
+	seq_printf(m, "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu oqlen=%ld/%ld\n",
+		   rsp->n_force_qs, rsp->n_force_qs_ngp,
+		   rsp->n_force_qs - rsp->n_force_qs_ngp,
+		   rsp->n_force_qs_lh, rsp->qlen_lazy, rsp->qlen);
+	for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < rcu_num_nodes; rnp++) {
+		if (rnp->level != level) {
+			seq_puts(m, "\n");
+			level = rnp->level;
+		}
+		seq_printf(m, "%lx/%lx %c%c>%c %d:%d ^%d    ",
+			   rnp->qsmask, rnp->qsmaskinit,
+			   ".G"[rnp->gp_tasks != NULL],
+			   ".E"[rnp->exp_tasks != NULL],
+			   ".T"[!list_empty(&rnp->blkd_tasks)],
+			   rnp->grplo, rnp->grphi, rnp->grpnum);
+	}
+	seq_puts(m, "\n");
+}
+
+static int show_rcuhier(struct seq_file *m, void *v)
+{
+	struct rcu_state *rsp = (struct rcu_state *)m->private;
+	print_one_rcu_state(m, rsp);
+	return 0;
+}
+
+static int rcuhier_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, show_rcuhier, inode->i_private);
+}
+
+static const struct file_operations rcuhier_fops = {
+	.owner = THIS_MODULE,
+	.open = rcuhier_open,
+	.read = seq_read,
+	.llseek = no_llseek,
+	.release = single_release,
+};
+
+static void show_one_rcugp(struct seq_file *m, struct rcu_state *rsp)
+{
+	unsigned long flags;
+	unsigned long completed;
+	unsigned long gpnum;
+	unsigned long gpage;
+	unsigned long gpmax;
+	struct rcu_node *rnp = &rsp->node[0];
+
+	raw_spin_lock_irqsave(&rnp->lock, flags);
+	completed = ACCESS_ONCE(rsp->completed);
+	gpnum = ACCESS_ONCE(rsp->gpnum);
+	if (completed == gpnum)
+		gpage = 0;
+	else
+		gpage = jiffies - rsp->gp_start;
+	gpmax = rsp->gp_max;
+	raw_spin_unlock_irqrestore(&rnp->lock, flags);
+	seq_printf(m, "completed=%ld  gpnum=%ld  age=%ld  max=%ld\n",
+		   ulong2long(completed), ulong2long(gpnum), gpage, gpmax);
+}
+
+static int show_rcugp(struct seq_file *m, void *v)
+{
+	struct rcu_state *rsp = (struct rcu_state *)m->private;
+	show_one_rcugp(m, rsp);
+	return 0;
+}
+
+static int rcugp_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, show_rcugp, inode->i_private);
+}
+
+static const struct file_operations rcugp_fops = {
+	.owner = THIS_MODULE,
+	.open = rcugp_open,
+	.read = seq_read,
+	.llseek = no_llseek,
+	.release = single_release,
+};
+
+static void print_one_rcu_pending(struct seq_file *m, struct rcu_data *rdp)
+{
+	if (!rdp->beenonline)
+		return;
+	seq_printf(m, "%3d%cnp=%ld ",
+		   rdp->cpu,
+		   cpu_is_offline(rdp->cpu) ? '!' : ' ',
+		   rdp->n_rcu_pending);
+	seq_printf(m, "qsp=%ld rpq=%ld cbr=%ld cng=%ld ",
+		   rdp->n_rp_qs_pending,
+		   rdp->n_rp_report_qs,
+		   rdp->n_rp_cb_ready,
+		   rdp->n_rp_cpu_needs_gp);
+	seq_printf(m, "gpc=%ld gps=%ld nn=%ld\n",
+		   rdp->n_rp_gp_completed,
+		   rdp->n_rp_gp_started,
+		   rdp->n_rp_need_nothing);
+}
+
+static int show_rcu_pending(struct seq_file *m, void *v)
+{
+	print_one_rcu_pending(m, (struct rcu_data *)v);
+	return 0;
+}
+
+static const struct seq_operations rcu_pending_op = {
+	.start = r_start,
+	.next  = r_next,
+	.stop  = r_stop,
+	.show  = show_rcu_pending,
+};
+
+static int rcu_pending_open(struct inode *inode, struct file *file)
+{
+	return r_open(inode, file, &rcu_pending_op);
+}
+
+static const struct file_operations rcu_pending_fops = {
+	.owner = THIS_MODULE,
+	.open = rcu_pending_open,
+	.read = seq_read,
+	.llseek = no_llseek,
+	.release = seq_release,
+};
+
+static int show_rcutorture(struct seq_file *m, void *unused)
+{
+	seq_printf(m, "rcutorture test sequence: %lu %s\n",
+		   rcutorture_testseq >> 1,
+		   (rcutorture_testseq & 0x1) ? "(test in progress)" : "");
+	seq_printf(m, "rcutorture update version number: %lu\n",
+		   rcutorture_vernum);
+	return 0;
+}
+
+static int rcutorture_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, show_rcutorture, NULL);
+}
+
+static const struct file_operations rcutorture_fops = {
+	.owner = THIS_MODULE,
+	.open = rcutorture_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+};
+
+static struct dentry *rcudir;
+
+static int __init rcutree_trace_init(void)
+{
+	struct rcu_state *rsp;
+	struct dentry *retval;
+	struct dentry *rspdir;
+
+	rcudir = debugfs_create_dir("rcu", NULL);
+	if (!rcudir)
+		goto free_out;
+
+	for_each_rcu_flavor(rsp) {
+		rspdir = debugfs_create_dir(rsp->name, rcudir);
+		if (!rspdir)
+			goto free_out;
+
+		retval = debugfs_create_file("rcudata", 0444,
+				rspdir, rsp, &rcudata_fops);
+		if (!retval)
+			goto free_out;
+
+		retval = debugfs_create_file("rcuexp", 0444,
+				rspdir, rsp, &rcuexp_fops);
+		if (!retval)
+			goto free_out;
+
+		retval = debugfs_create_file("rcu_pending", 0444,
+				rspdir, rsp, &rcu_pending_fops);
+		if (!retval)
+			goto free_out;
+
+		retval = debugfs_create_file("rcubarrier", 0444,
+				rspdir, rsp, &rcubarrier_fops);
+		if (!retval)
+			goto free_out;
+
+#ifdef CONFIG_RCU_BOOST
+		if (rsp == &rcu_preempt_state) {
+			retval = debugfs_create_file("rcuboost", 0444,
+				rspdir, NULL, &rcu_node_boost_fops);
+			if (!retval)
+				goto free_out;
+		}
+#endif
+
+		retval = debugfs_create_file("rcugp", 0444,
+				rspdir, rsp, &rcugp_fops);
+		if (!retval)
+			goto free_out;
+
+		retval = debugfs_create_file("rcuhier", 0444,
+				rspdir, rsp, &rcuhier_fops);
+		if (!retval)
+			goto free_out;
+	}
+
+	retval = debugfs_create_file("rcutorture", 0444, rcudir,
+						NULL, &rcutorture_fops);
+	if (!retval)
+		goto free_out;
+	return 0;
+free_out:
+	debugfs_remove_recursive(rcudir);
+	return 1;
+}
+
+static void __exit rcutree_trace_cleanup(void)
+{
+	debugfs_remove_recursive(rcudir);
+}
+
+
+module_init(rcutree_trace_init);
+module_exit(rcutree_trace_cleanup);
+
+MODULE_AUTHOR("Paul E. McKenney");
+MODULE_DESCRIPTION("Read-Copy Update tracing for hierarchical implementation");
+MODULE_LICENSE("GPL");