[linux-2.6-block.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"

static int show_rcubarrier(struct seq_file *m, void *unused)
{
	struct rcu_state *rsp;

	for_each_rcu_flavor(rsp)
		seq_printf(m, "%s: %c bcc: %d nbd: %lu\n",
			   rsp->name, rsp->rcu_barrier_in_progress ? 'B' : '.',
			   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, NULL);
}

static const struct file_operations rcubarrier_fops = {
	.owner = THIS_MODULE,
	.open = rcubarrier_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.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)
{
	if (!rdp->beenonline)
		return;
	seq_printf(m, "%3d%cc=%lu g=%lu pq=%d pgp=%lu qp=%d",
		   rdp->cpu,
		   cpu_is_offline(rdp->cpu) ? '!' : ' ',
		   rdp->completed, rdp->gpnum,
		   rdp->passed_quiesce, rdp->passed_quiesce_gpnum,
		   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);
	seq_printf(m, " ql=%ld/%ld qs=%c%c%c%c",
		   rdp->qlen_lazy, 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);
}

static int show_rcudata(struct seq_file *m, void *unused)
{
	int cpu;
	struct rcu_state *rsp;

	for_each_rcu_flavor(rsp) {
		seq_printf(m, "%s:\n", rsp->name);
		for_each_possible_cpu(cpu)
			print_one_rcu_data(m, per_cpu_ptr(rsp->rda, cpu));
	}
	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_quiesce, rdp->passed_quiesce_gpnum,
		   rdp->qs_pending);
	seq_printf(m, ",%d,%llx,%d,%lu",
		   atomic_read(&rdp->dynticks->dynticks),
		   rdp->dynticks->dynticks_nesting,
		   rdp->dynticks->dynticks_nmi_nesting,
		   rdp->dynticks_fqs);
	seq_printf(m, ",%lu", rdp->offline_fqs);
	seq_printf(m, ",%ld,%ld,\"%c%c%c%c\"", rdp->qlen_lazy, 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)
{
	int cpu;
	struct rcu_state *rsp;

	seq_puts(m, "\"CPU\",\"Online?\",\"c\",\"g\",\"pq\",\"pgp\",\"pq\",");
	seq_puts(m, "\"dt\",\"dt nesting\",\"dt NMI nesting\",\"df\",");
	seq_puts(m, "\"of\",\"qll\",\"ql\",\"qs\"");
#ifdef CONFIG_RCU_BOOST
	seq_puts(m, "\"kt\",\"ktl\"");
#endif /* #ifdef CONFIG_RCU_BOOST */
	seq_puts(m, ",\"b\",\"ci\",\"co\",\"ca\"\n");
	for_each_rcu_flavor(rsp) {
		seq_printf(m, "\"%s:\"\n", rsp->name);
		for_each_possible_cpu(cpu)
			print_one_rcu_data_csv(m, per_cpu_ptr(rsp->rda, cpu));
	}
	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 ",
		   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 = 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, "%s: c=%lu g=%lu s=%d jfq=%ld j=%x ",
		   rsp->name, rsp->completed, 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 *unused)
{
	struct rcu_state *rsp;

	for_each_rcu_flavor(rsp)
		print_one_rcu_state(m, rsp);
	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)
{
	struct rcu_state *rsp;

	for_each_rcu_flavor(rsp)
		show_one_rcugp(m, rsp);
	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 ",
		   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 nf=%ld nn=%ld\n",
		   rdp->n_rp_gp_completed,
		   rdp->n_rp_gp_started,
		   rdp->n_rp_need_fqs,
		   rdp->n_rp_need_nothing);
}

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

	for_each_rcu_flavor(rsp) {
		seq_printf(m, "%s:\n", rsp->name);
		for_each_possible_cpu(cpu) {
			rdp = per_cpu_ptr(rsp->rda, cpu);
			if (rdp->beenonline)
				print_one_rcu_pending(m, rdp);
		}
	}
	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("rcubarrier", 0444, rcudir,
						NULL, &rcubarrier_fops);
	if (!retval)
		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
d7e187c8 PM	49	static int show_rcubarrier(struct seq_file m, void unused)
d7e187c8 PM	50	{
c0cc962d PM	51	struct rcu_state *rsp;
	52
	53	for_each_rcu_flavor(rsp)
	54	seq_printf(m, "%s: %c bcc: %d nbd: %lu\n",
	55	rsp->name, rsp->rcu_barrier_in_progress ? 'B' : '.',
	56	atomic_read(&rsp->barrier_cpu_count),
	57	rsp->n_barrier_done);
d7e187c8 PM	58	return 0;
	59	}
	60
	61	static int rcubarrier_open(struct inode inode, struct file file)
	62	{
	63	return single_open(file, show_rcubarrier, NULL);
	64	}
	65
	66	static const struct file_operations rcubarrier_fops = {
	67	.owner = THIS_MODULE,
	68	.open = rcubarrier_open,
	69	.read = seq_read,
	70	.llseek = seq_lseek,
	71	.release = single_release,
	72	};
	73
a46e0899 PM	74	#ifdef CONFIG_RCU_BOOST
a46e0899 PM	75
d71df90e PM	76	static char convert_kthread_status(unsigned int kthread_status)
	77	{
	78	if (kthread_status > RCU_KTHREAD_MAX)
	79	return '?';
15ba0ba8	80	return "SRWOY"[kthread_status];
d71df90e PM	81	}
d71df90e PM	82
a46e0899 PM	83	#endif /* #ifdef CONFIG_RCU_BOOST */
a46e0899 PM	84
64db4cff PM	85	static void print_one_rcu_data(struct seq_file m, struct rcu_data rdp)
	86	{
	87	if (!rdp->beenonline)
	88	return;
e4cc1f22	89	seq_printf(m, "%3d%cc=%lu g=%lu pq=%d pgp=%lu qp=%d",
64db4cff PM	90	rdp->cpu,
	91	cpu_is_offline(rdp->cpu) ? '!' : ' ',
	92	rdp->completed, rdp->gpnum,
e4cc1f22	93	rdp->passed_quiesce, rdp->passed_quiesce_gpnum,
ef631b0c	94	rdp->qs_pending);
9b2e4f18	95	seq_printf(m, " dt=%d/%llx/%d df=%lu",
23b5c8fa	96	atomic_read(&rdp->dynticks->dynticks),
64db4cff	97	rdp->dynticks->dynticks_nesting,
23b5c8fa	98	rdp->dynticks->dynticks_nmi_nesting,
64db4cff	99	rdp->dynticks_fqs);
2036d94a	100	seq_printf(m, " of=%lu", rdp->offline_fqs);
486e2593 PM	101	seq_printf(m, " ql=%ld/%ld qs=%c%c%c%c",
486e2593 PM	102	rdp->qlen_lazy, rdp->qlen,
0ac3d136 PM	103	".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] !=
	104	rdp->nxttail[RCU_NEXT_TAIL]],
	105	".R"[rdp->nxttail[RCU_WAIT_TAIL] !=
	106	rdp->nxttail[RCU_NEXT_READY_TAIL]],
	107	".W"[rdp->nxttail[RCU_DONE_TAIL] !=
	108	rdp->nxttail[RCU_WAIT_TAIL]],
a46e0899 PM	109	".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]]);
	110	#ifdef CONFIG_RCU_BOOST
	111	seq_printf(m, " kt=%d/%c/%d ktl=%x",
d71df90e PM	112	per_cpu(rcu_cpu_has_work, rdp->cpu),
	113	convert_kthread_status(per_cpu(rcu_cpu_kthread_status,
	114	rdp->cpu)),
15ba0ba8	115	per_cpu(rcu_cpu_kthread_cpu, rdp->cpu),
a46e0899 PM	116	per_cpu(rcu_cpu_kthread_loops, rdp->cpu) & 0xffff);
	117	#endif /* #ifdef CONFIG_RCU_BOOST */
	118	seq_printf(m, " b=%ld", rdp->blimit);
269dcc1c PM	119	seq_printf(m, " ci=%lu co=%lu ca=%lu\n",
269dcc1c PM	120	rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted);
64db4cff PM	121	}
64db4cff PM	122
64db4cff PM	123	static int show_rcudata(struct seq_file m, void unused)
64db4cff PM	124	{
c0cc962d PM	125	int cpu;
	126	struct rcu_state *rsp;
	127
	128	for_each_rcu_flavor(rsp) {
	129	seq_printf(m, "%s:\n", rsp->name);
	130	for_each_possible_cpu(cpu)
	131	print_one_rcu_data(m, per_cpu_ptr(rsp->rda, cpu));
	132	}
64db4cff PM	133	return 0;
	134	}
	135
	136	static int rcudata_open(struct inode inode, struct file file)
	137	{
	138	return single_open(file, show_rcudata, NULL);
	139	}
	140
9b2619af	141	static const struct file_operations rcudata_fops = {
64db4cff PM	142	.owner = THIS_MODULE,
	143	.open = rcudata_open,
	144	.read = seq_read,
	145	.llseek = seq_lseek,
	146	.release = single_release,
	147	};
	148
	149	static void print_one_rcu_data_csv(struct seq_file m, struct rcu_data rdp)
	150	{
	151	if (!rdp->beenonline)
	152	return;
20133cfc	153	seq_printf(m, "%d,%s,%lu,%lu,%d,%lu,%d",
64db4cff	154	rdp->cpu,
5699ed8f	155	cpu_is_offline(rdp->cpu) ? "\"N\"" : "\"Y\"",
64db4cff	156	rdp->completed, rdp->gpnum,
e4cc1f22	157	rdp->passed_quiesce, rdp->passed_quiesce_gpnum,
ef631b0c	158	rdp->qs_pending);
9b2e4f18	159	seq_printf(m, ",%d,%llx,%d,%lu",
23b5c8fa	160	atomic_read(&rdp->dynticks->dynticks),
64db4cff	161	rdp->dynticks->dynticks_nesting,
23b5c8fa	162	rdp->dynticks->dynticks_nmi_nesting,
64db4cff	163	rdp->dynticks_fqs);
2036d94a	164	seq_printf(m, ",%lu", rdp->offline_fqs);
486e2593	165	seq_printf(m, ",%ld,%ld,\"%c%c%c%c\"", rdp->qlen_lazy, rdp->qlen,
0ac3d136 PM	166	".N"[rdp->nxttail[RCU_NEXT_READY_TAIL] !=
	167	rdp->nxttail[RCU_NEXT_TAIL]],
	168	".R"[rdp->nxttail[RCU_WAIT_TAIL] !=
	169	rdp->nxttail[RCU_NEXT_READY_TAIL]],
	170	".W"[rdp->nxttail[RCU_DONE_TAIL] !=
	171	rdp->nxttail[RCU_WAIT_TAIL]],
a46e0899 PM	172	".D"[&rdp->nxtlist != rdp->nxttail[RCU_DONE_TAIL]]);
	173	#ifdef CONFIG_RCU_BOOST
	174	seq_printf(m, ",%d,\"%c\"",
d71df90e PM	175	per_cpu(rcu_cpu_has_work, rdp->cpu),
d71df90e PM	176	convert_kthread_status(per_cpu(rcu_cpu_kthread_status,
a46e0899 PM	177	rdp->cpu)));
	178	#endif /* #ifdef CONFIG_RCU_BOOST */
	179	seq_printf(m, ",%ld", rdp->blimit);
269dcc1c PM	180	seq_printf(m, ",%lu,%lu,%lu\n",
269dcc1c PM	181	rdp->n_cbs_invoked, rdp->n_cbs_orphaned, rdp->n_cbs_adopted);
64db4cff PM	182	}
	183
	184	static int show_rcudata_csv(struct seq_file m, void unused)
	185	{
c0cc962d PM	186	int cpu;
	187	struct rcu_state *rsp;
	188
e4cc1f22	189	seq_puts(m, "\"CPU\",\"Online?\",\"c\",\"g\",\"pq\",\"pgp\",\"pq\",");
23b5c8fa	190	seq_puts(m, "\"dt\",\"dt nesting\",\"dt NMI nesting\",\"df\",");
2036d94a	191	seq_puts(m, "\"of\",\"qll\",\"ql\",\"qs\"");
a46e0899 PM	192	#ifdef CONFIG_RCU_BOOST
	193	seq_puts(m, "\"kt\",\"ktl\"");
	194	#endif /* #ifdef CONFIG_RCU_BOOST */
	195	seq_puts(m, ",\"b\",\"ci\",\"co\",\"ca\"\n");
c0cc962d PM	196	for_each_rcu_flavor(rsp) {
	197	seq_printf(m, "\"%s:\"\n", rsp->name);
	198	for_each_possible_cpu(cpu)
	199	print_one_rcu_data_csv(m, per_cpu_ptr(rsp->rda, cpu));
	200	}
64db4cff PM	201	return 0;
	202	}
	203
	204	static int rcudata_csv_open(struct inode inode, struct file file)
	205	{
	206	return single_open(file, show_rcudata_csv, NULL);
	207	}
	208
9b2619af	209	static const struct file_operations rcudata_csv_fops = {
64db4cff PM	210	.owner = THIS_MODULE,
	211	.open = rcudata_csv_open,
	212	.read = seq_read,
	213	.llseek = seq_lseek,
	214	.release = single_release,
	215	};
	216
0ea1f2eb PM	217	#ifdef CONFIG_RCU_BOOST
	218
	219	static void print_one_rcu_node_boost(struct seq_file m, struct rcu_node rnp)
	220	{
5cf05ad7	221	seq_printf(m, "%d:%d tasks=%c%c%c%c kt=%c ntb=%lu neb=%lu nnb=%lu ",
0ea1f2eb PM	222	rnp->grplo, rnp->grphi,
	223	"T."[list_empty(&rnp->blkd_tasks)],
	224	"N."[!rnp->gp_tasks],
	225	"E."[!rnp->exp_tasks],
	226	"B."[!rnp->boost_tasks],
d71df90e	227	convert_kthread_status(rnp->boost_kthread_status),
0ea1f2eb	228	rnp->n_tasks_boosted, rnp->n_exp_boosts,
5cf05ad7 PM	229	rnp->n_normal_boosts);
5cf05ad7 PM	230	seq_printf(m, "j=%04x bt=%04x\n",
0ea1f2eb PM	231	(int)(jiffies & 0xffff),
0ea1f2eb PM	232	(int)(rnp->boost_time & 0xffff));
5cf05ad7	233	seq_printf(m, " balk: nt=%lu egt=%lu bt=%lu nb=%lu ny=%lu nos=%lu\n",
0ea1f2eb PM	234	rnp->n_balk_blkd_tasks,
	235	rnp->n_balk_exp_gp_tasks,
	236	rnp->n_balk_boost_tasks,
	237	rnp->n_balk_notblocked,
	238	rnp->n_balk_notyet,
	239	rnp->n_balk_nos);
	240	}
	241
	242	static int show_rcu_node_boost(struct seq_file m, void unused)
	243	{
	244	struct rcu_node *rnp;
	245
	246	rcu_for_each_leaf_node(&rcu_preempt_state, rnp)
	247	print_one_rcu_node_boost(m, rnp);
	248	return 0;
	249	}
	250
	251	static int rcu_node_boost_open(struct inode inode, struct file file)
	252	{
	253	return single_open(file, show_rcu_node_boost, NULL);
	254	}
	255
	256	static const struct file_operations rcu_node_boost_fops = {
	257	.owner = THIS_MODULE,
	258	.open = rcu_node_boost_open,
	259	.read = seq_read,
	260	.llseek = seq_lseek,
	261	.release = single_release,
	262	};
	263
	264	/*
	265	* Create the rcuboost debugfs entry. Standard error return.
	266	*/
	267	static int rcu_boost_trace_create_file(struct dentry *rcudir)
	268	{
	269	return !debugfs_create_file("rcuboost", 0444, rcudir, NULL,
	270	&rcu_node_boost_fops);
	271	}
	272
	273	#else /* #ifdef CONFIG_RCU_BOOST */
	274
	275	static int rcu_boost_trace_create_file(struct dentry *rcudir)
	276	{
	277	return 0; /* There cannot be an error if we didn't create it! */
	278	}
	279
	280	#endif /* #else #ifdef CONFIG_RCU_BOOST */
	281
64db4cff PM	282	static void print_one_rcu_state(struct seq_file m, struct rcu_state rsp)
64db4cff PM	283	{
20133cfc	284	unsigned long gpnum;
64db4cff PM	285	int level = 0;
	286	struct rcu_node *rnp;
	287
3397e040	288	gpnum = rsp->gpnum;
5cf05ad7	289	seq_printf(m, "%s: c=%lu g=%lu s=%d jfq=%ld j=%x ",
c0cc962d	290	rsp->name, rsp->completed, gpnum, rsp->fqs_state,
64db4cff	291	(long)(rsp->jiffies_force_qs - jiffies),
5cf05ad7 PM	292	(int)(jiffies & 0xffff));
5cf05ad7 PM	293	seq_printf(m, "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu oqlen=%ld/%ld\n",
64db4cff PM	294	rsp->n_force_qs, rsp->n_force_qs_ngp,
64db4cff PM	295	rsp->n_force_qs - rsp->n_force_qs_ngp,
b1420f1c	296	rsp->n_force_qs_lh, rsp->qlen_lazy, rsp->qlen);
f885b7f2	297	for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < rcu_num_nodes; rnp++) {
64db4cff PM	298	if (rnp->level != level) {
	299	seq_puts(m, "\n");
	300	level = rnp->level;
	301	}
12f5f524	302	seq_printf(m, "%lx/%lx %c%c>%c %d:%d ^%d ",
64db4cff	303	rnp->qsmask, rnp->qsmaskinit,
12f5f524 PM	304	".G"[rnp->gp_tasks != NULL],
	305	".E"[rnp->exp_tasks != NULL],
	306	".T"[!list_empty(&rnp->blkd_tasks)],
64db4cff PM	307	rnp->grplo, rnp->grphi, rnp->grpnum);
	308	}
	309	seq_puts(m, "\n");
	310	}
	311
	312	static int show_rcuhier(struct seq_file m, void unused)
	313	{
c0cc962d PM	314	struct rcu_state *rsp;
	315
	316	for_each_rcu_flavor(rsp)
	317	print_one_rcu_state(m, rsp);
64db4cff PM	318	return 0;
	319	}
	320
	321	static int rcuhier_open(struct inode inode, struct file file)
	322	{
	323	return single_open(file, show_rcuhier, NULL);
	324	}
	325
9b2619af	326	static const struct file_operations rcuhier_fops = {
64db4cff PM	327	.owner = THIS_MODULE,
	328	.open = rcuhier_open,
	329	.read = seq_read,
	330	.llseek = seq_lseek,
	331	.release = single_release,
	332	};
	333
15ba0ba8 PM	334	static void show_one_rcugp(struct seq_file m, struct rcu_state rsp)
	335	{
	336	unsigned long flags;
	337	unsigned long completed;
	338	unsigned long gpnum;
	339	unsigned long gpage;
	340	unsigned long gpmax;
	341	struct rcu_node *rnp = &rsp->node[0];
	342
	343	raw_spin_lock_irqsave(&rnp->lock, flags);
	344	completed = rsp->completed;
	345	gpnum = rsp->gpnum;
	346	if (rsp->completed == rsp->gpnum)
	347	gpage = 0;
	348	else
	349	gpage = jiffies - rsp->gp_start;
	350	gpmax = rsp->gp_max;
	351	raw_spin_unlock_irqrestore(&rnp->lock, flags);
	352	seq_printf(m, "%s: completed=%ld gpnum=%lu age=%ld max=%ld\n",
	353	rsp->name, completed, gpnum, gpage, gpmax);
	354	}
	355
64db4cff PM	356	static int show_rcugp(struct seq_file m, void unused)
64db4cff PM	357	{
c0cc962d PM	358	struct rcu_state *rsp;
	359
	360	for_each_rcu_flavor(rsp)
	361	show_one_rcugp(m, rsp);
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)
7ba5c840 PM	379	{
5cf05ad7	380	seq_printf(m, "%3d%cnp=%ld ",
7ba5c840 PM	381	rdp->cpu,
7ba5c840 PM	382	cpu_is_offline(rdp->cpu) ? '!' : ' ',
5cf05ad7 PM	383	rdp->n_rcu_pending);
5cf05ad7 PM	384	seq_printf(m, "qsp=%ld rpq=%ld cbr=%ld cng=%ld ",
7ba5c840	385	rdp->n_rp_qs_pending,
d21670ac	386	rdp->n_rp_report_qs,
7ba5c840	387	rdp->n_rp_cb_ready,
5cf05ad7 PM	388	rdp->n_rp_cpu_needs_gp);
5cf05ad7 PM	389	seq_printf(m, "gpc=%ld gps=%ld nf=%ld nn=%ld\n",
7ba5c840 PM	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
c0cc962d	396	static int show_rcu_pending(struct seq_file m, void unused)
7ba5c840 PM	397	{
	398	int cpu;
	399	struct rcu_data *rdp;
c0cc962d PM	400	struct rcu_state *rsp;
	401
	402	for_each_rcu_flavor(rsp) {
	403	seq_printf(m, "%s:\n", rsp->name);
	404	for_each_possible_cpu(cpu) {
	405	rdp = per_cpu_ptr(rsp->rda, cpu);
	406	if (rdp->beenonline)
	407	print_one_rcu_pending(m, rdp);
	408	}
7ba5c840	409	}
7ba5c840 PM	410	return 0;
	411	}
	412
	413	static int rcu_pending_open(struct inode inode, struct file file)
	414	{
	415	return single_open(file, show_rcu_pending, NULL);
	416	}
	417
9b2619af	418	static const struct file_operations rcu_pending_fops = {
7ba5c840 PM	419	.owner = THIS_MODULE,
	420	.open = rcu_pending_open,
	421	.read = seq_read,
	422	.llseek = seq_lseek,
	423	.release = single_release,
	424	};
	425
4a298656 PM	426	static int show_rcutorture(struct seq_file m, void unused)
	427	{
	428	seq_printf(m, "rcutorture test sequence: %lu %s\n",
	429	rcutorture_testseq >> 1,
	430	(rcutorture_testseq & 0x1) ? "(test in progress)" : "");
	431	seq_printf(m, "rcutorture update version number: %lu\n",
	432	rcutorture_vernum);
	433	return 0;
	434	}
	435
	436	static int rcutorture_open(struct inode inode, struct file file)
	437	{
	438	return single_open(file, show_rcutorture, NULL);
	439	}
	440
	441	static const struct file_operations rcutorture_fops = {
	442	.owner = THIS_MODULE,
	443	.open = rcutorture_open,
	444	.read = seq_read,
	445	.llseek = seq_lseek,
	446	.release = single_release,
	447	};
	448
7ba5c840	449	static struct dentry *rcudir;
7ba5c840	450
deb7a418	451	static int __init rcutree_trace_init(void)
64db4cff	452	{
22f00b69 PM	453	struct dentry *retval;
22f00b69 PM	454
64db4cff PM	455	rcudir = debugfs_create_dir("rcu", NULL);
64db4cff PM	456	if (!rcudir)
22f00b69	457	goto free_out;
64db4cff	458
d7e187c8 PM	459	retval = debugfs_create_file("rcubarrier", 0444, rcudir,
	460	NULL, &rcubarrier_fops);
	461	if (!retval)
	462	goto free_out;
	463
22f00b69	464	retval = debugfs_create_file("rcudata", 0444, rcudir,
64db4cff	465	NULL, &rcudata_fops);
22f00b69	466	if (!retval)
64db4cff PM	467	goto free_out;
64db4cff PM	468
22f00b69	469	retval = debugfs_create_file("rcudata.csv", 0444, rcudir,
64db4cff	470	NULL, &rcudata_csv_fops);
22f00b69	471	if (!retval)
64db4cff PM	472	goto free_out;
64db4cff PM	473
0ea1f2eb PM	474	if (rcu_boost_trace_create_file(rcudir))
	475	goto free_out;
	476
22f00b69 PM	477	retval = debugfs_create_file("rcugp", 0444, rcudir, NULL, &rcugp_fops);
22f00b69 PM	478	if (!retval)
64db4cff PM	479	goto free_out;
64db4cff PM	480
22f00b69	481	retval = debugfs_create_file("rcuhier", 0444, rcudir,
64db4cff	482	NULL, &rcuhier_fops);
22f00b69	483	if (!retval)
64db4cff	484	goto free_out;
7ba5c840	485
22f00b69	486	retval = debugfs_create_file("rcu_pending", 0444, rcudir,
7ba5c840	487	NULL, &rcu_pending_fops);
22f00b69	488	if (!retval)
7ba5c840	489	goto free_out;
4a298656 PM	490
	491	retval = debugfs_create_file("rcutorture", 0444, rcudir,
	492	NULL, &rcutorture_fops);
	493	if (!retval)
	494	goto free_out;
64db4cff PM	495	return 0;
64db4cff PM	496	free_out:
22f00b69	497	debugfs_remove_recursive(rcudir);
64db4cff PM	498	return 1;
	499	}
	500
deb7a418	501	static void __exit rcutree_trace_cleanup(void)
64db4cff	502	{
22f00b69	503	debugfs_remove_recursive(rcudir);
64db4cff PM	504	}
	505
	506
deb7a418 PM	507	module_init(rcutree_trace_init);
deb7a418 PM	508	module_exit(rcutree_trace_cleanup);
64db4cff PM	509
	510	MODULE_AUTHOR("Paul E. McKenney");
	511	MODULE_DESCRIPTION("Read-Copy Update tracing for hierarchical implementation");
	512	MODULE_LICENSE("GPL");