[mirror_ubuntu-bionic-kernel.git] / kernel / rcu / tree_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, you can access it online at
 * http://www.gnu.org/licenses/gpl-2.0.html.
 *
 * 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"

DECLARE_PER_CPU_SHARED_ALIGNED(unsigned long, rcu_qs_ctr);

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/%d qp=%d",
		   rdp->cpu,
		   cpu_is_offline(rdp->cpu) ? '!' : ' ',
		   ulong2long(rdp->completed), ulong2long(rdp->gpnum),
		   rdp->passed_quiesce,
		   rdp->rcu_qs_ctr_snap == per_cpu(rcu_qs_ctr, rdp->cpu),
		   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, "t=%lu tf=%lu wd1=%lu wd2=%lu n=%lu enq=%d sc=%lu\n",
		   rsp->expedited_sequence,
		   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_read(&rsp->expedited_need_qs),
		   rsp->expedited_sequence / 2);
	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,
		   READ_ONCE(rsp->n_force_qs_lh), rsp->qlen_lazy, rsp->qlen);
	for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < rcu_num_nodes; rnp++) {
		if (rnp->level != level) {
			seq_puts(m, "\n");
			level = rnp->level;
		}
		seq_printf(m, "%lx/%lx->%lx %c%c>%c %d:%d ^%d    ",
			   rnp->qsmask, rnp->qsmaskinit, rnp->qsmaskinitnext,
			   ".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 = READ_ONCE(rsp->completed);
	gpnum = READ_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 ndw%ld\n",
		   rdp->n_rp_gp_completed,
		   rdp->n_rp_gp_started,
		   rdp->n_rp_nocb_defer_wakeup,
		   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");
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
87de1cfd PM	15	* along with this program; if not, you can access it online at
87de1cfd PM	16	* http://www.gnu.org/licenses/gpl-2.0.html.
64db4cff PM	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
4102adab	47	#include "tree.h"
6258c4fb	48
5cd37193 PM	49	DECLARE_PER_CPU_SHARED_ALIGNED(unsigned long, rcu_qs_ctr);
5cd37193 PM	50
374b928e MW	51	static int r_open(struct inode inode, struct file file,
	52	const struct seq_operations *op)
	53	{
	54	int ret = seq_open(file, op);
	55	if (!ret) {
	56	struct seq_file m = (struct seq_file )file->private_data;
	57	m->private = inode->i_private;
	58	}
	59	return ret;
	60	}
	61
	62	static void r_start(struct seq_file m, loff_t *pos)
	63	{
	64	struct rcu_state rsp = (struct rcu_state )m->private;
	65	pos = cpumask_next(pos - 1, cpu_possible_mask);
	66	if ((*pos) < nr_cpu_ids)
	67	return per_cpu_ptr(rsp->rda, *pos);
	68	return NULL;
	69	}
	70
	71	static void r_next(struct seq_file m, void v, loff_t pos)
	72	{
	73	(*pos)++;
	74	return r_start(m, pos);
	75	}
	76
	77	static void r_stop(struct seq_file m, void v)
	78	{
	79	}
	80
6ee0886f	81	static int show_rcubarrier(struct seq_file m, void v)
c25e557f MW	82	{
	83	struct rcu_state rsp = (struct rcu_state )m->private;
	84	seq_printf(m, "bcc: %d nbd: %lu\n",
	85	atomic_read(&rsp->barrier_cpu_count),
	86	rsp->n_barrier_done);
	87	return 0;
	88	}
	89
6ee0886f	90	static int rcubarrier_open(struct inode inode, struct file file)
c25e557f	91	{
6ee0886f	92	return single_open(file, show_rcubarrier, inode->i_private);
c25e557f MW	93	}
c25e557f MW	94
6ee0886f	95	static const struct file_operations rcubarrier_fops = {
c25e557f	96	.owner = THIS_MODULE,
6ee0886f	97	.open = rcubarrier_open,
c25e557f MW	98	.read = seq_read,
c25e557f MW	99	.llseek = no_llseek,
7ee2b9e5	100	.release = single_release,
c25e557f MW	101	};
c25e557f MW	102
a46e0899 PM	103	#ifdef CONFIG_RCU_BOOST
a46e0899 PM	104
d71df90e PM	105	static char convert_kthread_status(unsigned int kthread_status)
	106	{
	107	if (kthread_status > RCU_KTHREAD_MAX)
	108	return '?';
15ba0ba8	109	return "SRWOY"[kthread_status];
d71df90e PM	110	}
d71df90e PM	111
a46e0899 PM	112	#endif /* #ifdef CONFIG_RCU_BOOST */
a46e0899 PM	113
64db4cff PM	114	static void print_one_rcu_data(struct seq_file m, struct rcu_data rdp)
64db4cff PM	115	{
3fbfbf7a PM	116	long ql, qll;
3fbfbf7a PM	117
64db4cff PM	118	if (!rdp->beenonline)
64db4cff PM	119	return;
5cd37193	120	seq_printf(m, "%3d%cc=%ld g=%ld pq=%d/%d qp=%d",
64db4cff PM	121	rdp->cpu,
64db4cff PM	122	cpu_is_offline(rdp->cpu) ? '!' : ' ',
42c3533e	123	ulong2long(rdp->completed), ulong2long(rdp->gpnum),
5cd37193 PM	124	rdp->passed_quiesce,
	125	rdp->rcu_qs_ctr_snap == per_cpu(rcu_qs_ctr, rdp->cpu),
	126	rdp->qs_pending);
9b2e4f18	127	seq_printf(m, " dt=%d/%llx/%d df=%lu",
23b5c8fa	128	atomic_read(&rdp->dynticks->dynticks),
64db4cff	129	rdp->dynticks->dynticks_nesting,
23b5c8fa	130	rdp->dynticks->dynticks_nmi_nesting,
64db4cff	131	rdp->dynticks_fqs);
2036d94a	132	seq_printf(m, " of=%lu", rdp->offline_fqs);
3fbfbf7a PM	133	rcu_nocb_q_lengths(rdp, &ql, &qll);
	134	qll += rdp->qlen_lazy;
	135	ql += rdp->qlen;
486e2593	136	seq_printf(m, " ql=%ld/%ld qs=%c%c%c%c",
3fbfbf7a	137	qll, ql,
0ac3d136 PM	138	".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] !=
	139	rdp->nxttail[RCU_NEXT_TAIL]],
	140	".R"[rdp->nxttail[RCU_WAIT_TAIL] !=
	141	rdp->nxttail[RCU_NEXT_READY_TAIL]],
	142	".W"[rdp->nxttail[RCU_DONE_TAIL] !=
	143	rdp->nxttail[RCU_WAIT_TAIL]],
a46e0899 PM	144	".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]]);
a46e0899 PM	145	#ifdef CONFIG_RCU_BOOST
62ab7072	146	seq_printf(m, " kt=%d/%c ktl=%x",
d71df90e PM	147	per_cpu(rcu_cpu_has_work, rdp->cpu),
	148	convert_kthread_status(per_cpu(rcu_cpu_kthread_status,
	149	rdp->cpu)),
a46e0899 PM	150	per_cpu(rcu_cpu_kthread_loops, rdp->cpu) & 0xffff);
	151	#endif /* #ifdef CONFIG_RCU_BOOST */
	152	seq_printf(m, " b=%ld", rdp->blimit);
c635a4e1 PM	153	seq_printf(m, " ci=%lu nci=%lu co=%lu ca=%lu\n",
	154	rdp->n_cbs_invoked, rdp->n_nocbs_invoked,
	155	rdp->n_cbs_orphaned, rdp->n_cbs_adopted);
64db4cff PM	156	}
64db4cff PM	157
c011c41f	158	static int show_rcudata(struct seq_file m, void v)
878eda72 MW	159	{
	160	print_one_rcu_data(m, (struct rcu_data *)v);
	161	return 0;
	162	}
	163
c011c41f	164	static const struct seq_operations rcudate_op = {
878eda72 MW	165	.start = r_start,
	166	.next = r_next,
	167	.stop = r_stop,
c011c41f	168	.show = show_rcudata,
878eda72 MW	169	};
878eda72 MW	170
c011c41f	171	static int rcudata_open(struct inode inode, struct file file)
878eda72	172	{
c011c41f	173	return r_open(inode, file, &rcudate_op);
878eda72 MW	174	}
878eda72 MW	175
c011c41f	176	static const struct file_operations rcudata_fops = {
878eda72	177	.owner = THIS_MODULE,
c011c41f	178	.open = rcudata_open,
878eda72 MW	179	.read = seq_read,
	180	.llseek = no_llseek,
	181	.release = seq_release,
	182	};
	183
7bd8f2a7 PM	184	static int show_rcuexp(struct seq_file m, void v)
	185	{
	186	struct rcu_state rsp = (struct rcu_state )m->private;
	187
3a6d7c64	188	seq_printf(m, "t=%lu tf=%lu wd1=%lu wd2=%lu n=%lu enq=%d sc=%lu\n",
d6ada2cf	189	rsp->expedited_sequence,
7bd8f2a7 PM	190	atomic_long_read(&rsp->expedited_tryfail),
	191	atomic_long_read(&rsp->expedited_workdone1),
	192	atomic_long_read(&rsp->expedited_workdone2),
	193	atomic_long_read(&rsp->expedited_normal),
3a6d7c64	194	atomic_read(&rsp->expedited_need_qs),
d6ada2cf	195	rsp->expedited_sequence / 2);
7bd8f2a7 PM	196	return 0;
	197	}
	198
	199	static int rcuexp_open(struct inode inode, struct file file)
	200	{
	201	return single_open(file, show_rcuexp, inode->i_private);
	202	}
	203
	204	static const struct file_operations rcuexp_fops = {
	205	.owner = THIS_MODULE,
	206	.open = rcuexp_open,
	207	.read = seq_read,
	208	.llseek = no_llseek,
7ee2b9e5	209	.release = single_release,
7bd8f2a7 PM	210	};
7bd8f2a7 PM	211
0ea1f2eb PM	212	#ifdef CONFIG_RCU_BOOST
	213
	214	static void print_one_rcu_node_boost(struct seq_file m, struct rcu_node rnp)
	215	{
5cf05ad7	216	seq_printf(m, "%d:%d tasks=%c%c%c%c kt=%c ntb=%lu neb=%lu nnb=%lu ",
0ea1f2eb PM	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	223	rnp->n_tasks_boosted, rnp->n_exp_boosts,
5cf05ad7 PM	224	rnp->n_normal_boosts);
5cf05ad7 PM	225	seq_printf(m, "j=%04x bt=%04x\n",
0ea1f2eb PM	226	(int)(jiffies & 0xffff),
0ea1f2eb PM	227	(int)(rnp->boost_time & 0xffff));
5cf05ad7	228	seq_printf(m, " balk: nt=%lu egt=%lu bt=%lu nb=%lu ny=%lu nos=%lu\n",
0ea1f2eb PM	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,
29c67764	255	.llseek = no_llseek,
0ea1f2eb PM	256	.release = single_release,
	257	};
	258
6ee0886f	259	#endif /* #ifdef CONFIG_RCU_BOOST */
0ea1f2eb	260
64db4cff PM	261	static void print_one_rcu_state(struct seq_file m, struct rcu_state rsp)
64db4cff PM	262	{
20133cfc	263	unsigned long gpnum;
64db4cff PM	264	int level = 0;
	265	struct rcu_node *rnp;
	266
3397e040	267	gpnum = rsp->gpnum;
6ee0886f MW	268	seq_printf(m, "c=%ld g=%ld s=%d jfq=%ld j=%x ",
6ee0886f MW	269	ulong2long(rsp->completed), ulong2long(gpnum),
42c3533e	270	rsp->fqs_state,
64db4cff	271	(long)(rsp->jiffies_force_qs - jiffies),
5cf05ad7 PM	272	(int)(jiffies & 0xffff));
5cf05ad7 PM	273	seq_printf(m, "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu oqlen=%ld/%ld\n",
64db4cff PM	274	rsp->n_force_qs, rsp->n_force_qs_ngp,
64db4cff PM	275	rsp->n_force_qs - rsp->n_force_qs_ngp,
7d0ae808	276	READ_ONCE(rsp->n_force_qs_lh), rsp->qlen_lazy, rsp->qlen);
f885b7f2	277	for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < rcu_num_nodes; rnp++) {
64db4cff PM	278	if (rnp->level != level) {
	279	seq_puts(m, "\n");
	280	level = rnp->level;
	281	}
0aa04b05 PM	282	seq_printf(m, "%lx/%lx->%lx %c%c>%c %d:%d ^%d ",
0aa04b05 PM	283	rnp->qsmask, rnp->qsmaskinit, rnp->qsmaskinitnext,
12f5f524 PM	284	".G"[rnp->gp_tasks != NULL],
	285	".E"[rnp->exp_tasks != NULL],
	286	".T"[!list_empty(&rnp->blkd_tasks)],
64db4cff PM	287	rnp->grplo, rnp->grphi, rnp->grpnum);
	288	}
	289	seq_puts(m, "\n");
	290	}
	291
6ee0886f	292	static int show_rcuhier(struct seq_file m, void v)
64db4cff	293	{
6ee0886f MW	294	struct rcu_state rsp = (struct rcu_state )m->private;
6ee0886f MW	295	print_one_rcu_state(m, rsp);
64db4cff PM	296	return 0;
	297	}
	298
	299	static int rcuhier_open(struct inode inode, struct file file)
	300	{
6ee0886f	301	return single_open(file, show_rcuhier, inode->i_private);
64db4cff PM	302	}
64db4cff PM	303
9b2619af	304	static const struct file_operations rcuhier_fops = {
64db4cff PM	305	.owner = THIS_MODULE,
	306	.open = rcuhier_open,
	307	.read = seq_read,
a608d84b	308	.llseek = no_llseek,
7ee2b9e5	309	.release = single_release,
a608d84b MW	310	};
a608d84b MW	311
15ba0ba8 PM	312	static void show_one_rcugp(struct seq_file m, struct rcu_state rsp)
	313	{
	314	unsigned long flags;
	315	unsigned long completed;
	316	unsigned long gpnum;
	317	unsigned long gpage;
	318	unsigned long gpmax;
	319	struct rcu_node *rnp = &rsp->node[0];
	320
	321	raw_spin_lock_irqsave(&rnp->lock, flags);
7d0ae808 PM	322	completed = READ_ONCE(rsp->completed);
7d0ae808 PM	323	gpnum = READ_ONCE(rsp->gpnum);
42c3533e	324	if (completed == gpnum)
15ba0ba8 PM	325	gpage = 0;
	326	else
	327	gpage = jiffies - rsp->gp_start;
	328	gpmax = rsp->gp_max;
	329	raw_spin_unlock_irqrestore(&rnp->lock, flags);
6ee0886f MW	330	seq_printf(m, "completed=%ld gpnum=%ld age=%ld max=%ld\n",
6ee0886f MW	331	ulong2long(completed), ulong2long(gpnum), gpage, gpmax);
15ba0ba8 PM	332	}
15ba0ba8 PM	333
6ee0886f	334	static int show_rcugp(struct seq_file m, void v)
64db4cff	335	{
6ee0886f MW	336	struct rcu_state rsp = (struct rcu_state )m->private;
6ee0886f MW	337	show_one_rcugp(m, rsp);
64db4cff PM	338	return 0;
	339	}
	340
	341	static int rcugp_open(struct inode inode, struct file file)
	342	{
6ee0886f	343	return single_open(file, show_rcugp, inode->i_private);
64db4cff PM	344	}
64db4cff PM	345
9b2619af	346	static const struct file_operations rcugp_fops = {
64db4cff PM	347	.owner = THIS_MODULE,
	348	.open = rcugp_open,
	349	.read = seq_read,
66b38bc5	350	.llseek = no_llseek,
7ee2b9e5	351	.release = single_release,
66b38bc5 MW	352	};
66b38bc5 MW	353
7ba5c840 PM	354	static void print_one_rcu_pending(struct seq_file m, struct rcu_data rdp)
7ba5c840 PM	355	{
51d0f16d MW	356	if (!rdp->beenonline)
51d0f16d MW	357	return;
5cf05ad7	358	seq_printf(m, "%3d%cnp=%ld ",
7ba5c840 PM	359	rdp->cpu,
7ba5c840 PM	360	cpu_is_offline(rdp->cpu) ? '!' : ' ',
5cf05ad7 PM	361	rdp->n_rcu_pending);
5cf05ad7 PM	362	seq_printf(m, "qsp=%ld rpq=%ld cbr=%ld cng=%ld ",
7ba5c840	363	rdp->n_rp_qs_pending,
d21670ac	364	rdp->n_rp_report_qs,
7ba5c840	365	rdp->n_rp_cb_ready,
5cf05ad7	366	rdp->n_rp_cpu_needs_gp);
96d3fd0d	367	seq_printf(m, "gpc=%ld gps=%ld nn=%ld ndw%ld\n",
7ba5c840 PM	368	rdp->n_rp_gp_completed,
7ba5c840 PM	369	rdp->n_rp_gp_started,
96d3fd0d	370	rdp->n_rp_nocb_defer_wakeup,
7ba5c840 PM	371	rdp->n_rp_need_nothing);
	372	}
	373
c011c41f	374	static int show_rcu_pending(struct seq_file m, void v)
51d0f16d MW	375	{
	376	print_one_rcu_pending(m, (struct rcu_data *)v);
	377	return 0;
	378	}
	379
c011c41f	380	static const struct seq_operations rcu_pending_op = {
51d0f16d MW	381	.start = r_start,
	382	.next = r_next,
	383	.stop = r_stop,
c011c41f	384	.show = show_rcu_pending,
51d0f16d MW	385	};
51d0f16d MW	386
c011c41f	387	static int rcu_pending_open(struct inode inode, struct file file)
51d0f16d	388	{
c011c41f	389	return r_open(inode, file, &rcu_pending_op);
51d0f16d MW	390	}
51d0f16d MW	391
c011c41f	392	static const struct file_operations rcu_pending_fops = {
51d0f16d	393	.owner = THIS_MODULE,
c011c41f	394	.open = rcu_pending_open,
51d0f16d MW	395	.read = seq_read,
	396	.llseek = no_llseek,
	397	.release = seq_release,
	398	};
	399
4a298656 PM	400	static int show_rcutorture(struct seq_file m, void unused)
	401	{
	402	seq_printf(m, "rcutorture test sequence: %lu %s\n",
	403	rcutorture_testseq >> 1,
	404	(rcutorture_testseq & 0x1) ? "(test in progress)" : "");
	405	seq_printf(m, "rcutorture update version number: %lu\n",
	406	rcutorture_vernum);
	407	return 0;
	408	}
	409
	410	static int rcutorture_open(struct inode inode, struct file file)
	411	{
	412	return single_open(file, show_rcutorture, NULL);
	413	}
	414
	415	static const struct file_operations rcutorture_fops = {
	416	.owner = THIS_MODULE,
	417	.open = rcutorture_open,
	418	.read = seq_read,
	419	.llseek = seq_lseek,
	420	.release = single_release,
	421	};
	422
7ba5c840	423	static struct dentry *rcudir;
7ba5c840	424
deb7a418	425	static int __init rcutree_trace_init(void)
64db4cff	426	{
573bcd40	427	struct rcu_state *rsp;
22f00b69	428	struct dentry *retval;
573bcd40	429	struct dentry *rspdir;
22f00b69	430
64db4cff PM	431	rcudir = debugfs_create_dir("rcu", NULL);
64db4cff PM	432	if (!rcudir)
22f00b69	433	goto free_out;
64db4cff	434
573bcd40 MW	435	for_each_rcu_flavor(rsp) {
	436	rspdir = debugfs_create_dir(rsp->name, rcudir);
	437	if (!rspdir)
	438	goto free_out;
878eda72	439
6ee0886f MW	440	retval = debugfs_create_file("rcudata", 0444,
	441	rspdir, rsp, &rcudata_fops);
	442	if (!retval)
	443	goto free_out;
51d0f16d	444
7bd8f2a7 PM	445	retval = debugfs_create_file("rcuexp", 0444,
	446	rspdir, rsp, &rcuexp_fops);
	447	if (!retval)
	448	goto free_out;
	449
6ee0886f MW	450	retval = debugfs_create_file("rcu_pending", 0444,
	451	rspdir, rsp, &rcu_pending_fops);
	452	if (!retval)
	453	goto free_out;
c25e557f	454
6ee0886f MW	455	retval = debugfs_create_file("rcubarrier", 0444,
	456	rspdir, rsp, &rcubarrier_fops);
	457	if (!retval)
	458	goto free_out;
29c67764 MW	459
29c67764 MW	460	#ifdef CONFIG_RCU_BOOST
6ee0886f MW	461	if (rsp == &rcu_preempt_state) {
	462	retval = debugfs_create_file("rcuboost", 0444,
	463	rspdir, NULL, &rcu_node_boost_fops);
66b38bc5 MW	464	if (!retval)
66b38bc5 MW	465	goto free_out;
6ee0886f MW	466	}
6ee0886f MW	467	#endif
66b38bc5	468
6ee0886f MW	469	retval = debugfs_create_file("rcugp", 0444,
	470	rspdir, rsp, &rcugp_fops);
	471	if (!retval)
	472	goto free_out;
64db4cff	473
6ee0886f MW	474	retval = debugfs_create_file("rcuhier", 0444,
	475	rspdir, rsp, &rcuhier_fops);
	476	if (!retval)
	477	goto free_out;
	478	}
7ba5c840	479
4a298656 PM	480	retval = debugfs_create_file("rcutorture", 0444, rcudir,
	481	NULL, &rcutorture_fops);
	482	if (!retval)
	483	goto free_out;
64db4cff PM	484	return 0;
64db4cff PM	485	free_out:
22f00b69	486	debugfs_remove_recursive(rcudir);
64db4cff PM	487	return 1;
	488	}
	489
deb7a418	490	static void __exit rcutree_trace_cleanup(void)
64db4cff	491	{
22f00b69	492	debugfs_remove_recursive(rcudir);
64db4cff PM	493	}
	494
	495
deb7a418 PM	496	module_init(rcutree_trace_init);
deb7a418 PM	497	module_exit(rcutree_trace_cleanup);
64db4cff PM	498
	499	MODULE_AUTHOR("Paul E. McKenney");
	500	MODULE_DESCRIPTION("Read-Copy Update tracing for hierarchical implementation");
	501	MODULE_LICENSE("GPL");