[deliverable/linux.git] / kernel / rcutree_trace.c

/*
 * 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 "rcutree.h"

#ifdef CONFIG_RCU_BOOST

DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_cpu);
DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
DECLARE_PER_CPU(char, rcu_cpu_has_work);

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)
{
	if (!rdp->beenonline)
		return;
	seq_printf(m, "%3d%cc=%lu g=%lu pq=%d pqc=%lu qp=%d",
		   rdp->cpu,
		   cpu_is_offline(rdp->cpu) ? '!' : ' ',
		   rdp->completed, rdp->gpnum,
		   rdp->passed_quiesc, rdp->passed_quiesc_completed,
		   rdp->qs_pending);
#ifdef CONFIG_NO_HZ
	seq_printf(m, " dt=%d/%d/%d df=%lu",
		   atomic_read(&rdp->dynticks->dynticks),
		   rdp->dynticks->dynticks_nesting,
		   rdp->dynticks->dynticks_nmi_nesting,
		   rdp->dynticks_fqs);
#endif /* #ifdef CONFIG_NO_HZ */
	seq_printf(m, " of=%lu ri=%lu", rdp->offline_fqs, rdp->resched_ipi);
	seq_printf(m, " ql=%ld qs=%c%c%c%c",
		   rdp->qlen,
		   ".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/%d 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_cpu, 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 co=%lu ca=%lu\n",
		   rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted);
}

#define PRINT_RCU_DATA(name, func, m) \
	do { \
		int _p_r_d_i; \
		\
		for_each_possible_cpu(_p_r_d_i) \
			func(m, &per_cpu(name, _p_r_d_i)); \
	} while (0)

static int show_rcudata(struct seq_file *m, void *unused)
{
#ifdef CONFIG_TREE_PREEMPT_RCU
	seq_puts(m, "rcu_preempt:\n");
	PRINT_RCU_DATA(rcu_preempt_data, print_one_rcu_data, m);
#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
	seq_puts(m, "rcu_sched:\n");
	PRINT_RCU_DATA(rcu_sched_data, print_one_rcu_data, m);
	seq_puts(m, "rcu_bh:\n");
	PRINT_RCU_DATA(rcu_bh_data, print_one_rcu_data, m);
	return 0;
}

static int rcudata_open(struct inode *inode, struct file *file)
{
	return single_open(file, show_rcudata, NULL);
}

static const struct file_operations rcudata_fops = {
	.owner = THIS_MODULE,
	.open = rcudata_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
};

static void print_one_rcu_data_csv(struct seq_file *m, struct rcu_data *rdp)
{
	if (!rdp->beenonline)
		return;
	seq_printf(m, "%d,%s,%lu,%lu,%d,%lu,%d",
		   rdp->cpu,
		   cpu_is_offline(rdp->cpu) ? "\"N\"" : "\"Y\"",
		   rdp->completed, rdp->gpnum,
		   rdp->passed_quiesc, rdp->passed_quiesc_completed,
		   rdp->qs_pending);
#ifdef CONFIG_NO_HZ
	seq_printf(m, ",%d,%d,%d,%lu",
		   atomic_read(&rdp->dynticks->dynticks),
		   rdp->dynticks->dynticks_nesting,
		   rdp->dynticks->dynticks_nmi_nesting,
		   rdp->dynticks_fqs);
#endif /* #ifdef CONFIG_NO_HZ */
	seq_printf(m, ",%lu,%lu", rdp->offline_fqs, rdp->resched_ipi);
	seq_printf(m, ",%ld,\"%c%c%c%c\"", rdp->qlen,
		   ".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, ",%d,\"%c\"",
		   per_cpu(rcu_cpu_has_work, rdp->cpu),
		   convert_kthread_status(per_cpu(rcu_cpu_kthread_status,
					  rdp->cpu)));
#endif /* #ifdef CONFIG_RCU_BOOST */
	seq_printf(m, ",%ld", rdp->blimit);
	seq_printf(m, ",%lu,%lu,%lu\n",
		   rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted);
}

static int show_rcudata_csv(struct seq_file *m, void *unused)
{
	seq_puts(m, "\"CPU\",\"Online?\",\"c\",\"g\",\"pq\",\"pqc\",\"pq\",");
#ifdef CONFIG_NO_HZ
	seq_puts(m, "\"dt\",\"dt nesting\",\"dt NMI nesting\",\"df\",");
#endif /* #ifdef CONFIG_NO_HZ */
	seq_puts(m, "\"of\",\"ri\",\"ql\",\"qs\"");
#ifdef CONFIG_RCU_BOOST
	seq_puts(m, "\"kt\",\"ktl\"");
#endif /* #ifdef CONFIG_RCU_BOOST */
	seq_puts(m, ",\"b\",\"ci\",\"co\",\"ca\"\n");
#ifdef CONFIG_TREE_PREEMPT_RCU
	seq_puts(m, "\"rcu_preempt:\"\n");
	PRINT_RCU_DATA(rcu_preempt_data, print_one_rcu_data_csv, m);
#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
	seq_puts(m, "\"rcu_sched:\"\n");
	PRINT_RCU_DATA(rcu_sched_data, print_one_rcu_data_csv, m);
	seq_puts(m, "\"rcu_bh:\"\n");
	PRINT_RCU_DATA(rcu_bh_data, print_one_rcu_data_csv, m);
	return 0;
}

static int rcudata_csv_open(struct inode *inode, struct file *file)
{
	return single_open(file, show_rcudata_csv, NULL);
}

static const struct file_operations rcudata_csv_fops = {
	.owner = THIS_MODULE,
	.open = rcudata_csv_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.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 "
		   "j=%04x bt=%04x\n",
		   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,
		   (int)(jiffies & 0xffff),
		   (int)(rnp->boost_time & 0xffff));
	seq_printf(m, "%s: nt=%lu egt=%lu bt=%lu nb=%lu ny=%lu nos=%lu\n",
		   "     balk",
		   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 = seq_lseek,
	.release = single_release,
};

/*
 * Create the rcuboost debugfs entry.  Standard error return.
 */
static int rcu_boost_trace_create_file(struct dentry *rcudir)
{
	return !debugfs_create_file("rcuboost", 0444, rcudir, NULL,
				    &rcu_node_boost_fops);
}

#else /* #ifdef CONFIG_RCU_BOOST */

static int rcu_boost_trace_create_file(struct dentry *rcudir)
{
	return 0;  /* There cannot be an error if we didn't create it! */
}

#endif /* #else #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=%lu g=%lu s=%d jfq=%ld j=%x "
		      "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu\n",
		   rsp->completed, gpnum, rsp->signaled,
		   (long)(rsp->jiffies_force_qs - jiffies),
		   (int)(jiffies & 0xffff),
		   rsp->n_force_qs, rsp->n_force_qs_ngp,
		   rsp->n_force_qs - rsp->n_force_qs_ngp,
		   rsp->n_force_qs_lh);
	for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < NUM_RCU_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 *unused)
{
#ifdef CONFIG_TREE_PREEMPT_RCU
	seq_puts(m, "rcu_preempt:\n");
	print_one_rcu_state(m, &rcu_preempt_state);
#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
	seq_puts(m, "rcu_sched:\n");
	print_one_rcu_state(m, &rcu_sched_state);
	seq_puts(m, "rcu_bh:\n");
	print_one_rcu_state(m, &rcu_bh_state);
	return 0;
}

static int rcuhier_open(struct inode *inode, struct file *file)
{
	return single_open(file, show_rcuhier, NULL);
}

static const struct file_operations rcuhier_fops = {
	.owner = THIS_MODULE,
	.open = rcuhier_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.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 = rsp->completed;
	gpnum = rsp->gpnum;
	if (rsp->completed == rsp->gpnum)
		gpage = 0;
	else
		gpage = jiffies - rsp->gp_start;
	gpmax = rsp->gp_max;
	raw_spin_unlock_irqrestore(&rnp->lock, flags);
	seq_printf(m, "%s: completed=%ld  gpnum=%lu  age=%ld  max=%ld\n",
		   rsp->name, completed, gpnum, gpage, gpmax);
}

static int show_rcugp(struct seq_file *m, void *unused)
{
#ifdef CONFIG_TREE_PREEMPT_RCU
	show_one_rcugp(m, &rcu_preempt_state);
#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
	show_one_rcugp(m, &rcu_sched_state);
	show_one_rcugp(m, &rcu_bh_state);
	return 0;
}

static int rcugp_open(struct inode *inode, struct file *file)
{
	return single_open(file, show_rcugp, NULL);
}

static const struct file_operations rcugp_fops = {
	.owner = THIS_MODULE,
	.open = rcugp_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
};

static void print_one_rcu_pending(struct seq_file *m, struct rcu_data *rdp)
{
	seq_printf(m, "%3d%cnp=%ld "
		   "qsp=%ld rpq=%ld cbr=%ld cng=%ld "
		   "gpc=%ld gps=%ld nf=%ld nn=%ld\n",
		   rdp->cpu,
		   cpu_is_offline(rdp->cpu) ? '!' : ' ',
		   rdp->n_rcu_pending,
		   rdp->n_rp_qs_pending,
		   rdp->n_rp_report_qs,
		   rdp->n_rp_cb_ready,
		   rdp->n_rp_cpu_needs_gp,
		   rdp->n_rp_gp_completed,
		   rdp->n_rp_gp_started,
		   rdp->n_rp_need_fqs,
		   rdp->n_rp_need_nothing);
}

static void print_rcu_pendings(struct seq_file *m, struct rcu_state *rsp)
{
	int cpu;
	struct rcu_data *rdp;

	for_each_possible_cpu(cpu) {
		rdp = per_cpu_ptr(rsp->rda, cpu);
		if (rdp->beenonline)
			print_one_rcu_pending(m, rdp);
	}
}

static int show_rcu_pending(struct seq_file *m, void *unused)
{
#ifdef CONFIG_TREE_PREEMPT_RCU
	seq_puts(m, "rcu_preempt:\n");
	print_rcu_pendings(m, &rcu_preempt_state);
#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
	seq_puts(m, "rcu_sched:\n");
	print_rcu_pendings(m, &rcu_sched_state);
	seq_puts(m, "rcu_bh:\n");
	print_rcu_pendings(m, &rcu_bh_state);
	return 0;
}

static int rcu_pending_open(struct inode *inode, struct file *file)
{
	return single_open(file, show_rcu_pending, NULL);
}

static const struct file_operations rcu_pending_fops = {
	.owner = THIS_MODULE,
	.open = rcu_pending_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_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 dentry *retval;

	rcudir = debugfs_create_dir("rcu", NULL);
	if (!rcudir)
		goto free_out;

	retval = debugfs_create_file("rcudata", 0444, rcudir,
						NULL, &rcudata_fops);
	if (!retval)
		goto free_out;

	retval = debugfs_create_file("rcudata.csv", 0444, rcudir,
						NULL, &rcudata_csv_fops);
	if (!retval)
		goto free_out;

	if (rcu_boost_trace_create_file(rcudir))
		goto free_out;

	retval = debugfs_create_file("rcugp", 0444, rcudir, NULL, &rcugp_fops);
	if (!retval)
		goto free_out;

	retval = debugfs_create_file("rcuhier", 0444, rcudir,
						NULL, &rcuhier_fops);
	if (!retval)
		goto free_out;

	retval = debugfs_create_file("rcu_pending", 0444, rcudir,
						NULL, &rcu_pending_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");
Commit	Line	Data
64db4cff PM	1	/*
	2	* Read-Copy Update tracing for classic implementation
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License as published by
	6	* the Free Software Foundation; either version 2 of the License, or
	7	* (at your option) any later version.
	8	*
	9	* This program is distributed in the hope that it will be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
	13	*
	14	* You should have received a copy of the GNU General Public License
	15	* along with this program; if not, write to the Free Software
	16	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	17	*
	18	* Copyright IBM Corporation, 2008
	19	*
	20	* Papers: http://www.rdrop.com/users/paulmck/RCU
	21	*
	22	* For detailed explanation of Read-Copy Update mechanism see -
a71fca58	23	* Documentation/RCU
64db4cff PM	24	*
	25	*/
	26	#include <linux/types.h>
	27	#include <linux/kernel.h>
	28	#include <linux/init.h>
	29	#include <linux/spinlock.h>
	30	#include <linux/smp.h>
	31	#include <linux/rcupdate.h>
	32	#include <linux/interrupt.h>
	33	#include <linux/sched.h>
60063497	34	#include <linux/atomic.h>
64db4cff PM	35	#include <linux/bitops.h>
	36	#include <linux/module.h>
	37	#include <linux/completion.h>
	38	#include <linux/moduleparam.h>
	39	#include <linux/percpu.h>
	40	#include <linux/notifier.h>
	41	#include <linux/cpu.h>
	42	#include <linux/mutex.h>
	43	#include <linux/debugfs.h>
	44	#include <linux/seq_file.h>
	45
9f77da9f	46	#define RCU_TREE_NONCORE
6258c4fb IM	47	#include "rcutree.h"
6258c4fb IM	48
a46e0899 PM	49	#ifdef CONFIG_RCU_BOOST
a46e0899 PM	50
d71df90e	51	DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
15ba0ba8	52	DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_cpu);
5ece5bab	53	DECLARE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
d71df90e PM	54	DECLARE_PER_CPU(char, rcu_cpu_has_work);
	55
	56	static char convert_kthread_status(unsigned int kthread_status)
	57	{
	58	if (kthread_status > RCU_KTHREAD_MAX)
	59	return '?';
15ba0ba8	60	return "SRWOY"[kthread_status];
d71df90e PM	61	}
d71df90e PM	62
a46e0899 PM	63	#endif /* #ifdef CONFIG_RCU_BOOST */
a46e0899 PM	64
64db4cff PM	65	static void print_one_rcu_data(struct seq_file m, struct rcu_data rdp)
	66	{
	67	if (!rdp->beenonline)
	68	return;
20133cfc	69	seq_printf(m, "%3d%cc=%lu g=%lu pq=%d pqc=%lu qp=%d",
64db4cff PM	70	rdp->cpu,
	71	cpu_is_offline(rdp->cpu) ? '!' : ' ',
	72	rdp->completed, rdp->gpnum,
	73	rdp->passed_quiesc, rdp->passed_quiesc_completed,
ef631b0c	74	rdp->qs_pending);
64db4cff	75	#ifdef CONFIG_NO_HZ
23b5c8fa PM	76	seq_printf(m, " dt=%d/%d/%d df=%lu",
23b5c8fa PM	77	atomic_read(&rdp->dynticks->dynticks),
64db4cff	78	rdp->dynticks->dynticks_nesting,
23b5c8fa	79	rdp->dynticks->dynticks_nmi_nesting,
64db4cff PM	80	rdp->dynticks_fqs);
	81	#endif /* #ifdef CONFIG_NO_HZ */
	82	seq_printf(m, " of=%lu ri=%lu", rdp->offline_fqs, rdp->resched_ipi);
a46e0899	83	seq_printf(m, " ql=%ld qs=%c%c%c%c",
0ac3d136 PM	84	rdp->qlen,
	85	".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] !=
	86	rdp->nxttail[RCU_NEXT_TAIL]],
	87	".R"[rdp->nxttail[RCU_WAIT_TAIL] !=
	88	rdp->nxttail[RCU_NEXT_READY_TAIL]],
	89	".W"[rdp->nxttail[RCU_DONE_TAIL] !=
	90	rdp->nxttail[RCU_WAIT_TAIL]],
a46e0899 PM	91	".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]]);
	92	#ifdef CONFIG_RCU_BOOST
	93	seq_printf(m, " kt=%d/%c/%d ktl=%x",
d71df90e PM	94	per_cpu(rcu_cpu_has_work, rdp->cpu),
	95	convert_kthread_status(per_cpu(rcu_cpu_kthread_status,
	96	rdp->cpu)),
15ba0ba8	97	per_cpu(rcu_cpu_kthread_cpu, rdp->cpu),
a46e0899 PM	98	per_cpu(rcu_cpu_kthread_loops, rdp->cpu) & 0xffff);
	99	#endif /* #ifdef CONFIG_RCU_BOOST */
	100	seq_printf(m, " b=%ld", rdp->blimit);
269dcc1c PM	101	seq_printf(m, " ci=%lu co=%lu ca=%lu\n",
269dcc1c PM	102	rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted);
64db4cff PM	103	}
	104
	105	#define PRINT_RCU_DATA(name, func, m) \
	106	do { \
	107	int _p_r_d_i; \
	108	\
	109	for_each_possible_cpu(_p_r_d_i) \
	110	func(m, &per_cpu(name, _p_r_d_i)); \
	111	} while (0)
	112
	113	static int show_rcudata(struct seq_file m, void unused)
	114	{
f41d911f PM	115	#ifdef CONFIG_TREE_PREEMPT_RCU
	116	seq_puts(m, "rcu_preempt:\n");
	117	PRINT_RCU_DATA(rcu_preempt_data, print_one_rcu_data, m);
	118	#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
d6714c22 PM	119	seq_puts(m, "rcu_sched:\n");
d6714c22 PM	120	PRINT_RCU_DATA(rcu_sched_data, print_one_rcu_data, m);
64db4cff PM	121	seq_puts(m, "rcu_bh:\n");
	122	PRINT_RCU_DATA(rcu_bh_data, print_one_rcu_data, m);
	123	return 0;
	124	}
	125
	126	static int rcudata_open(struct inode inode, struct file file)
	127	{
	128	return single_open(file, show_rcudata, NULL);
	129	}
	130
9b2619af	131	static const struct file_operations rcudata_fops = {
64db4cff PM	132	.owner = THIS_MODULE,
	133	.open = rcudata_open,
	134	.read = seq_read,
	135	.llseek = seq_lseek,
	136	.release = single_release,
	137	};
	138
	139	static void print_one_rcu_data_csv(struct seq_file m, struct rcu_data rdp)
	140	{
	141	if (!rdp->beenonline)
	142	return;
20133cfc	143	seq_printf(m, "%d,%s,%lu,%lu,%d,%lu,%d",
64db4cff	144	rdp->cpu,
5699ed8f	145	cpu_is_offline(rdp->cpu) ? "\"N\"" : "\"Y\"",
64db4cff PM	146	rdp->completed, rdp->gpnum,
64db4cff PM	147	rdp->passed_quiesc, rdp->passed_quiesc_completed,
ef631b0c	148	rdp->qs_pending);
64db4cff PM	149	#ifdef CONFIG_NO_HZ
64db4cff PM	150	seq_printf(m, ",%d,%d,%d,%lu",
23b5c8fa	151	atomic_read(&rdp->dynticks->dynticks),
64db4cff	152	rdp->dynticks->dynticks_nesting,
23b5c8fa	153	rdp->dynticks->dynticks_nmi_nesting,
64db4cff PM	154	rdp->dynticks_fqs);
	155	#endif /* #ifdef CONFIG_NO_HZ */
	156	seq_printf(m, ",%lu,%lu", rdp->offline_fqs, rdp->resched_ipi);
a46e0899	157	seq_printf(m, ",%ld,\"%c%c%c%c\"", rdp->qlen,
0ac3d136 PM	158	".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] !=
	159	rdp->nxttail[RCU_NEXT_TAIL]],
	160	".R"[rdp->nxttail[RCU_WAIT_TAIL] !=
	161	rdp->nxttail[RCU_NEXT_READY_TAIL]],
	162	".W"[rdp->nxttail[RCU_DONE_TAIL] !=
	163	rdp->nxttail[RCU_WAIT_TAIL]],
a46e0899 PM	164	".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]]);
	165	#ifdef CONFIG_RCU_BOOST
	166	seq_printf(m, ",%d,\"%c\"",
d71df90e PM	167	per_cpu(rcu_cpu_has_work, rdp->cpu),
d71df90e PM	168	convert_kthread_status(per_cpu(rcu_cpu_kthread_status,
a46e0899 PM	169	rdp->cpu)));
	170	#endif /* #ifdef CONFIG_RCU_BOOST */
	171	seq_printf(m, ",%ld", rdp->blimit);
269dcc1c PM	172	seq_printf(m, ",%lu,%lu,%lu\n",
269dcc1c PM	173	rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted);
64db4cff PM	174	}
	175
	176	static int show_rcudata_csv(struct seq_file m, void unused)
	177	{
ef631b0c	178	seq_puts(m, "\"CPU\",\"Online?\",\"c\",\"g\",\"pq\",\"pqc\",\"pq\",");
64db4cff	179	#ifdef CONFIG_NO_HZ
23b5c8fa	180	seq_puts(m, "\"dt\",\"dt nesting\",\"dt NMI nesting\",\"df\",");
64db4cff	181	#endif /* #ifdef CONFIG_NO_HZ */
a46e0899 PM	182	seq_puts(m, "\"of\",\"ri\",\"ql\",\"qs\"");
	183	#ifdef CONFIG_RCU_BOOST
	184	seq_puts(m, "\"kt\",\"ktl\"");
	185	#endif /* #ifdef CONFIG_RCU_BOOST */
	186	seq_puts(m, ",\"b\",\"ci\",\"co\",\"ca\"\n");
f41d911f PM	187	#ifdef CONFIG_TREE_PREEMPT_RCU
	188	seq_puts(m, "\"rcu_preempt:\"\n");
	189	PRINT_RCU_DATA(rcu_preempt_data, print_one_rcu_data_csv, m);
	190	#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
d6714c22 PM	191	seq_puts(m, "\"rcu_sched:\"\n");
d6714c22 PM	192	PRINT_RCU_DATA(rcu_sched_data, print_one_rcu_data_csv, m);
64db4cff PM	193	seq_puts(m, "\"rcu_bh:\"\n");
	194	PRINT_RCU_DATA(rcu_bh_data, print_one_rcu_data_csv, m);
	195	return 0;
	196	}
	197
	198	static int rcudata_csv_open(struct inode inode, struct file file)
	199	{
	200	return single_open(file, show_rcudata_csv, NULL);
	201	}
	202
9b2619af	203	static const struct file_operations rcudata_csv_fops = {
64db4cff PM	204	.owner = THIS_MODULE,
	205	.open = rcudata_csv_open,
	206	.read = seq_read,
	207	.llseek = seq_lseek,
	208	.release = single_release,
	209	};
	210
0ea1f2eb PM	211	#ifdef CONFIG_RCU_BOOST
	212
	213	static void print_one_rcu_node_boost(struct seq_file m, struct rcu_node rnp)
	214	{
d71df90e	215	seq_printf(m, "%d:%d tasks=%c%c%c%c kt=%c ntb=%lu neb=%lu nnb=%lu "
0ea1f2eb PM	216	"j=%04x bt=%04x\n",
	217	rnp->grplo, rnp->grphi,
	218	"T."[list_empty(&rnp->blkd_tasks)],
	219	"N."[!rnp->gp_tasks],
	220	"E."[!rnp->exp_tasks],
	221	"B."[!rnp->boost_tasks],
d71df90e	222	convert_kthread_status(rnp->boost_kthread_status),
0ea1f2eb PM	223	rnp->n_tasks_boosted, rnp->n_exp_boosts,
	224	rnp->n_normal_boosts,
	225	(int)(jiffies & 0xffff),
	226	(int)(rnp->boost_time & 0xffff));
	227	seq_printf(m, "%s: nt=%lu egt=%lu bt=%lu nb=%lu ny=%lu nos=%lu\n",
	228	" balk",
	229	rnp->n_balk_blkd_tasks,
	230	rnp->n_balk_exp_gp_tasks,
	231	rnp->n_balk_boost_tasks,
	232	rnp->n_balk_notblocked,
	233	rnp->n_balk_notyet,
	234	rnp->n_balk_nos);
	235	}
	236
	237	static int show_rcu_node_boost(struct seq_file m, void unused)
	238	{
	239	struct rcu_node *rnp;
	240
	241	rcu_for_each_leaf_node(&rcu_preempt_state, rnp)
	242	print_one_rcu_node_boost(m, rnp);
	243	return 0;
	244	}
	245
	246	static int rcu_node_boost_open(struct inode inode, struct file file)
	247	{
	248	return single_open(file, show_rcu_node_boost, NULL);
	249	}
	250
	251	static const struct file_operations rcu_node_boost_fops = {
	252	.owner = THIS_MODULE,
	253	.open = rcu_node_boost_open,
	254	.read = seq_read,
	255	.llseek = seq_lseek,
	256	.release = single_release,
	257	};
	258
	259	/*
	260	* Create the rcuboost debugfs entry. Standard error return.
	261	*/
	262	static int rcu_boost_trace_create_file(struct dentry *rcudir)
	263	{
	264	return !debugfs_create_file("rcuboost", 0444, rcudir, NULL,
	265	&rcu_node_boost_fops);
	266	}
	267
	268	#else /* #ifdef CONFIG_RCU_BOOST */
	269
	270	static int rcu_boost_trace_create_file(struct dentry *rcudir)
	271	{
	272	return 0; /* There cannot be an error if we didn't create it! */
	273	}
	274
	275	#endif /* #else #ifdef CONFIG_RCU_BOOST */
	276
64db4cff PM	277	static void print_one_rcu_state(struct seq_file m, struct rcu_state rsp)
64db4cff PM	278	{
20133cfc	279	unsigned long gpnum;
64db4cff PM	280	int level = 0;
	281	struct rcu_node *rnp;
	282
3397e040	283	gpnum = rsp->gpnum;
20133cfc	284	seq_printf(m, "c=%lu g=%lu s=%d jfq=%ld j=%x "
29494be7	285	"nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu\n",
3397e040	286	rsp->completed, gpnum, rsp->signaled,
64db4cff PM	287	(long)(rsp->jiffies_force_qs - jiffies),
	288	(int)(jiffies & 0xffff),
	289	rsp->n_force_qs, rsp->n_force_qs_ngp,
	290	rsp->n_force_qs - rsp->n_force_qs_ngp,
29494be7	291	rsp->n_force_qs_lh);
64db4cff PM	292	for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < NUM_RCU_NODES; rnp++) {
	293	if (rnp->level != level) {
	294	seq_puts(m, "\n");
	295	level = rnp->level;
	296	}
12f5f524	297	seq_printf(m, "%lx/%lx %c%c>%c %d:%d ^%d ",
64db4cff	298	rnp->qsmask, rnp->qsmaskinit,
12f5f524 PM	299	".G"[rnp->gp_tasks != NULL],
	300	".E"[rnp->exp_tasks != NULL],
	301	".T"[!list_empty(&rnp->blkd_tasks)],
64db4cff PM	302	rnp->grplo, rnp->grphi, rnp->grpnum);
	303	}
	304	seq_puts(m, "\n");
	305	}
	306
	307	static int show_rcuhier(struct seq_file m, void unused)
	308	{
f41d911f PM	309	#ifdef CONFIG_TREE_PREEMPT_RCU
	310	seq_puts(m, "rcu_preempt:\n");
	311	print_one_rcu_state(m, &rcu_preempt_state);
	312	#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
d6714c22 PM	313	seq_puts(m, "rcu_sched:\n");
d6714c22 PM	314	print_one_rcu_state(m, &rcu_sched_state);
64db4cff PM	315	seq_puts(m, "rcu_bh:\n");
	316	print_one_rcu_state(m, &rcu_bh_state);
	317	return 0;
	318	}
	319
	320	static int rcuhier_open(struct inode inode, struct file file)
	321	{
	322	return single_open(file, show_rcuhier, NULL);
	323	}
	324
9b2619af	325	static const struct file_operations rcuhier_fops = {
64db4cff PM	326	.owner = THIS_MODULE,
	327	.open = rcuhier_open,
	328	.read = seq_read,
	329	.llseek = seq_lseek,
	330	.release = single_release,
	331	};
	332
15ba0ba8 PM	333	static void show_one_rcugp(struct seq_file m, struct rcu_state rsp)
	334	{
	335	unsigned long flags;
	336	unsigned long completed;
	337	unsigned long gpnum;
	338	unsigned long gpage;
	339	unsigned long gpmax;
	340	struct rcu_node *rnp = &rsp->node[0];
	341
	342	raw_spin_lock_irqsave(&rnp->lock, flags);
	343	completed = rsp->completed;
	344	gpnum = rsp->gpnum;
	345	if (rsp->completed == rsp->gpnum)
	346	gpage = 0;
	347	else
	348	gpage = jiffies - rsp->gp_start;
	349	gpmax = rsp->gp_max;
	350	raw_spin_unlock_irqrestore(&rnp->lock, flags);
	351	seq_printf(m, "%s: completed=%ld gpnum=%lu age=%ld max=%ld\n",
	352	rsp->name, completed, gpnum, gpage, gpmax);
	353	}
	354
64db4cff PM	355	static int show_rcugp(struct seq_file m, void unused)
64db4cff PM	356	{
f41d911f	357	#ifdef CONFIG_TREE_PREEMPT_RCU
15ba0ba8	358	show_one_rcugp(m, &rcu_preempt_state);
f41d911f	359	#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
15ba0ba8 PM	360	show_one_rcugp(m, &rcu_sched_state);
15ba0ba8 PM	361	show_one_rcugp(m, &rcu_bh_state);
64db4cff PM	362	return 0;
	363	}
	364
	365	static int rcugp_open(struct inode inode, struct file file)
	366	{
	367	return single_open(file, show_rcugp, NULL);
	368	}
	369
9b2619af	370	static const struct file_operations rcugp_fops = {
64db4cff PM	371	.owner = THIS_MODULE,
	372	.open = rcugp_open,
	373	.read = seq_read,
	374	.llseek = seq_lseek,
	375	.release = single_release,
	376	};
	377
7ba5c840 PM	378	static void print_one_rcu_pending(struct seq_file m, struct rcu_data rdp)
	379	{
	380	seq_printf(m, "%3d%cnp=%ld "
d21670ac PM	381	"qsp=%ld rpq=%ld cbr=%ld cng=%ld "
d21670ac PM	382	"gpc=%ld gps=%ld nf=%ld nn=%ld\n",
7ba5c840 PM	383	rdp->cpu,
	384	cpu_is_offline(rdp->cpu) ? '!' : ' ',
	385	rdp->n_rcu_pending,
	386	rdp->n_rp_qs_pending,
d21670ac	387	rdp->n_rp_report_qs,
7ba5c840 PM	388	rdp->n_rp_cb_ready,
	389	rdp->n_rp_cpu_needs_gp,
	390	rdp->n_rp_gp_completed,
	391	rdp->n_rp_gp_started,
	392	rdp->n_rp_need_fqs,
	393	rdp->n_rp_need_nothing);
	394	}
	395
	396	static void print_rcu_pendings(struct seq_file m, struct rcu_state rsp)
	397	{
	398	int cpu;
	399	struct rcu_data *rdp;
	400
	401	for_each_possible_cpu(cpu) {
394f99a9	402	rdp = per_cpu_ptr(rsp->rda, cpu);
7ba5c840 PM	403	if (rdp->beenonline)
	404	print_one_rcu_pending(m, rdp);
	405	}
	406	}
	407
	408	static int show_rcu_pending(struct seq_file m, void unused)
	409	{
f41d911f PM	410	#ifdef CONFIG_TREE_PREEMPT_RCU
	411	seq_puts(m, "rcu_preempt:\n");
	412	print_rcu_pendings(m, &rcu_preempt_state);
	413	#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
d6714c22 PM	414	seq_puts(m, "rcu_sched:\n");
d6714c22 PM	415	print_rcu_pendings(m, &rcu_sched_state);
7ba5c840 PM	416	seq_puts(m, "rcu_bh:\n");
	417	print_rcu_pendings(m, &rcu_bh_state);
	418	return 0;
	419	}
	420
	421	static int rcu_pending_open(struct inode inode, struct file file)
	422	{
	423	return single_open(file, show_rcu_pending, NULL);
	424	}
	425
9b2619af	426	static const struct file_operations rcu_pending_fops = {
7ba5c840 PM	427	.owner = THIS_MODULE,
	428	.open = rcu_pending_open,
	429	.read = seq_read,
	430	.llseek = seq_lseek,
	431	.release = single_release,
	432	};
	433
4a298656 PM	434	static int show_rcutorture(struct seq_file m, void unused)
	435	{
	436	seq_printf(m, "rcutorture test sequence: %lu %s\n",
	437	rcutorture_testseq >> 1,
	438	(rcutorture_testseq & 0x1) ? "(test in progress)" : "");
	439	seq_printf(m, "rcutorture update version number: %lu\n",
	440	rcutorture_vernum);
	441	return 0;
	442	}
	443
	444	static int rcutorture_open(struct inode inode, struct file file)
	445	{
	446	return single_open(file, show_rcutorture, NULL);
	447	}
	448
	449	static const struct file_operations rcutorture_fops = {
	450	.owner = THIS_MODULE,
	451	.open = rcutorture_open,
	452	.read = seq_read,
	453	.llseek = seq_lseek,
	454	.release = single_release,
	455	};
	456
7ba5c840	457	static struct dentry *rcudir;
7ba5c840	458
deb7a418	459	static int __init rcutree_trace_init(void)
64db4cff	460	{
22f00b69 PM	461	struct dentry *retval;
22f00b69 PM	462
64db4cff PM	463	rcudir = debugfs_create_dir("rcu", NULL);
64db4cff PM	464	if (!rcudir)
22f00b69	465	goto free_out;
64db4cff	466
22f00b69	467	retval = debugfs_create_file("rcudata", 0444, rcudir,
64db4cff	468	NULL, &rcudata_fops);
22f00b69	469	if (!retval)
64db4cff PM	470	goto free_out;
64db4cff PM	471
22f00b69	472	retval = debugfs_create_file("rcudata.csv", 0444, rcudir,
64db4cff	473	NULL, &rcudata_csv_fops);
22f00b69	474	if (!retval)
64db4cff PM	475	goto free_out;
64db4cff PM	476
0ea1f2eb PM	477	if (rcu_boost_trace_create_file(rcudir))
	478	goto free_out;
	479
22f00b69 PM	480	retval = debugfs_create_file("rcugp", 0444, rcudir, NULL, &rcugp_fops);
22f00b69 PM	481	if (!retval)
64db4cff PM	482	goto free_out;
64db4cff PM	483
22f00b69	484	retval = debugfs_create_file("rcuhier", 0444, rcudir,
64db4cff	485	NULL, &rcuhier_fops);
22f00b69	486	if (!retval)
64db4cff	487	goto free_out;
7ba5c840	488
22f00b69	489	retval = debugfs_create_file("rcu_pending", 0444, rcudir,
7ba5c840	490	NULL, &rcu_pending_fops);
22f00b69	491	if (!retval)
7ba5c840	492	goto free_out;
4a298656 PM	493
	494	retval = debugfs_create_file("rcutorture", 0444, rcudir,
	495	NULL, &rcutorture_fops);
	496	if (!retval)
	497	goto free_out;
64db4cff PM	498	return 0;
64db4cff PM	499	free_out:
22f00b69	500	debugfs_remove_recursive(rcudir);
64db4cff PM	501	return 1;
	502	}
	503
deb7a418	504	static void __exit rcutree_trace_cleanup(void)
64db4cff	505	{
22f00b69	506	debugfs_remove_recursive(rcudir);
64db4cff PM	507	}
	508
	509
deb7a418 PM	510	module_init(rcutree_trace_init);
deb7a418 PM	511	module_exit(rcutree_trace_cleanup);
64db4cff PM	512
	513	MODULE_AUTHOR("Paul E. McKenney");
	514	MODULE_DESCRIPTION("Read-Copy Update tracing for hierarchical implementation");
	515	MODULE_LICENSE("GPL");