[linux-2.6-block.git] / kernel / locking / lockdep_proc.c

// SPDX-License-Identifier: GPL-2.0
/*
 * kernel/lockdep_proc.c
 *
 * Runtime locking correctness validator
 *
 * Started by Ingo Molnar:
 *
 *  Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
 *  Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
 *
 * Code for /proc/lockdep and /proc/lockdep_stats:
 *
 */
#include <linux/export.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/kallsyms.h>
#include <linux/debug_locks.h>
#include <linux/vmalloc.h>
#include <linux/sort.h>
#include <linux/uaccess.h>
#include <asm/div64.h>

#include "lockdep_internals.h"

static void *l_next(struct seq_file *m, void *v, loff_t *pos)
{
	return seq_list_next(v, &all_lock_classes, pos);
}

static void *l_start(struct seq_file *m, loff_t *pos)
{
	return seq_list_start_head(&all_lock_classes, *pos);
}

static void l_stop(struct seq_file *m, void *v)
{
}

static void print_name(struct seq_file *m, struct lock_class *class)
{
	char str[KSYM_NAME_LEN];
	const char *name = class->name;

	if (!name) {
		name = __get_key_name(class->key, str);
		seq_printf(m, "%s", name);
	} else{
		seq_printf(m, "%s", name);
		if (class->name_version > 1)
			seq_printf(m, "#%d", class->name_version);
		if (class->subclass)
			seq_printf(m, "/%d", class->subclass);
	}
}

static int l_show(struct seq_file *m, void *v)
{
	struct lock_class *class = list_entry(v, struct lock_class, lock_entry);
	struct lock_list *entry;
	char usage[LOCK_USAGE_CHARS];

	if (v == &all_lock_classes) {
		seq_printf(m, "all lock classes:\n");
		return 0;
	}

	seq_printf(m, "%p", class->key);
#ifdef CONFIG_DEBUG_LOCKDEP
	seq_printf(m, " OPS:%8ld", debug_class_ops_read(class));
#endif
#ifdef CONFIG_PROVE_LOCKING
	seq_printf(m, " FD:%5ld", lockdep_count_forward_deps(class));
	seq_printf(m, " BD:%5ld", lockdep_count_backward_deps(class));
#endif

	get_usage_chars(class, usage);
	seq_printf(m, " %s", usage);

	seq_printf(m, ": ");
	print_name(m, class);
	seq_puts(m, "\n");

	list_for_each_entry(entry, &class->locks_after, entry) {
		if (entry->distance == 1) {
			seq_printf(m, " -> [%p] ", entry->class->key);
			print_name(m, entry->class);
			seq_puts(m, "\n");
		}
	}
	seq_puts(m, "\n");

	return 0;
}

static const struct seq_operations lockdep_ops = {
	.start	= l_start,
	.next	= l_next,
	.stop	= l_stop,
	.show	= l_show,
};

#ifdef CONFIG_PROVE_LOCKING
static void *lc_start(struct seq_file *m, loff_t *pos)
{
	if (*pos < 0)
		return NULL;

	if (*pos == 0)
		return SEQ_START_TOKEN;

	return lock_chains + (*pos - 1);
}

static void *lc_next(struct seq_file *m, void *v, loff_t *pos)
{
	*pos = lockdep_next_lockchain(*pos - 1) + 1;
	return lc_start(m, pos);
}

static void lc_stop(struct seq_file *m, void *v)
{
}

static int lc_show(struct seq_file *m, void *v)
{
	struct lock_chain *chain = v;
	struct lock_class *class;
	int i;

	if (v == SEQ_START_TOKEN) {
		if (nr_chain_hlocks > MAX_LOCKDEP_CHAIN_HLOCKS)
			seq_printf(m, "(buggered) ");
		seq_printf(m, "all lock chains:\n");
		return 0;
	}

	seq_printf(m, "irq_context: %d\n", chain->irq_context);

	for (i = 0; i < chain->depth; i++) {
		class = lock_chain_get_class(chain, i);
		if (!class->key)
			continue;

		seq_printf(m, "[%p] ", class->key);
		print_name(m, class);
		seq_puts(m, "\n");
	}
	seq_puts(m, "\n");

	return 0;
}

static const struct seq_operations lockdep_chains_ops = {
	.start	= lc_start,
	.next	= lc_next,
	.stop	= lc_stop,
	.show	= lc_show,
};
#endif /* CONFIG_PROVE_LOCKING */

static void lockdep_stats_debug_show(struct seq_file *m)
{
#ifdef CONFIG_DEBUG_LOCKDEP
	unsigned long long hi1 = debug_atomic_read(hardirqs_on_events),
			   hi2 = debug_atomic_read(hardirqs_off_events),
			   hr1 = debug_atomic_read(redundant_hardirqs_on),
			   hr2 = debug_atomic_read(redundant_hardirqs_off),
			   si1 = debug_atomic_read(softirqs_on_events),
			   si2 = debug_atomic_read(softirqs_off_events),
			   sr1 = debug_atomic_read(redundant_softirqs_on),
			   sr2 = debug_atomic_read(redundant_softirqs_off);

	seq_printf(m, " chain lookup misses:           %11llu\n",
		debug_atomic_read(chain_lookup_misses));
	seq_printf(m, " chain lookup hits:             %11llu\n",
		debug_atomic_read(chain_lookup_hits));
	seq_printf(m, " cyclic checks:                 %11llu\n",
		debug_atomic_read(nr_cyclic_checks));
	seq_printf(m, " redundant checks:              %11llu\n",
		debug_atomic_read(nr_redundant_checks));
	seq_printf(m, " redundant links:               %11llu\n",
		debug_atomic_read(nr_redundant));
	seq_printf(m, " find-mask forwards checks:     %11llu\n",
		debug_atomic_read(nr_find_usage_forwards_checks));
	seq_printf(m, " find-mask backwards checks:    %11llu\n",
		debug_atomic_read(nr_find_usage_backwards_checks));

	seq_printf(m, " hardirq on events:             %11llu\n", hi1);
	seq_printf(m, " hardirq off events:            %11llu\n", hi2);
	seq_printf(m, " redundant hardirq ons:         %11llu\n", hr1);
	seq_printf(m, " redundant hardirq offs:        %11llu\n", hr2);
	seq_printf(m, " softirq on events:             %11llu\n", si1);
	seq_printf(m, " softirq off events:            %11llu\n", si2);
	seq_printf(m, " redundant softirq ons:         %11llu\n", sr1);
	seq_printf(m, " redundant softirq offs:        %11llu\n", sr2);
#endif
}

static int lockdep_stats_show(struct seq_file *m, void *v)
{
	unsigned long nr_unused = 0, nr_uncategorized = 0,
		      nr_irq_safe = 0, nr_irq_unsafe = 0,
		      nr_softirq_safe = 0, nr_softirq_unsafe = 0,
		      nr_hardirq_safe = 0, nr_hardirq_unsafe = 0,
		      nr_irq_read_safe = 0, nr_irq_read_unsafe = 0,
		      nr_softirq_read_safe = 0, nr_softirq_read_unsafe = 0,
		      nr_hardirq_read_safe = 0, nr_hardirq_read_unsafe = 0,
		      sum_forward_deps = 0;

#ifdef CONFIG_PROVE_LOCKING
	struct lock_class *class;

	list_for_each_entry(class, &all_lock_classes, lock_entry) {

		if (class->usage_mask == 0)
			nr_unused++;
		if (class->usage_mask == LOCKF_USED)
			nr_uncategorized++;
		if (class->usage_mask & LOCKF_USED_IN_IRQ)
			nr_irq_safe++;
		if (class->usage_mask & LOCKF_ENABLED_IRQ)
			nr_irq_unsafe++;
		if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ)
			nr_softirq_safe++;
		if (class->usage_mask & LOCKF_ENABLED_SOFTIRQ)
			nr_softirq_unsafe++;
		if (class->usage_mask & LOCKF_USED_IN_HARDIRQ)
			nr_hardirq_safe++;
		if (class->usage_mask & LOCKF_ENABLED_HARDIRQ)
			nr_hardirq_unsafe++;
		if (class->usage_mask & LOCKF_USED_IN_IRQ_READ)
			nr_irq_read_safe++;
		if (class->usage_mask & LOCKF_ENABLED_IRQ_READ)
			nr_irq_read_unsafe++;
		if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ_READ)
			nr_softirq_read_safe++;
		if (class->usage_mask & LOCKF_ENABLED_SOFTIRQ_READ)
			nr_softirq_read_unsafe++;
		if (class->usage_mask & LOCKF_USED_IN_HARDIRQ_READ)
			nr_hardirq_read_safe++;
		if (class->usage_mask & LOCKF_ENABLED_HARDIRQ_READ)
			nr_hardirq_read_unsafe++;

		sum_forward_deps += lockdep_count_forward_deps(class);
	}
#ifdef CONFIG_DEBUG_LOCKDEP
	DEBUG_LOCKS_WARN_ON(debug_atomic_read(nr_unused_locks) != nr_unused);
#endif

#endif
	seq_printf(m, " lock-classes:                  %11lu [max: %lu]\n",
			nr_lock_classes, MAX_LOCKDEP_KEYS);
	seq_printf(m, " direct dependencies:           %11lu [max: %lu]\n",
			nr_list_entries, MAX_LOCKDEP_ENTRIES);
	seq_printf(m, " indirect dependencies:         %11lu\n",
			sum_forward_deps);

	/*
	 * Total number of dependencies:
	 *
	 * All irq-safe locks may nest inside irq-unsafe locks,
	 * plus all the other known dependencies:
	 */
	seq_printf(m, " all direct dependencies:       %11lu\n",
			nr_irq_unsafe * nr_irq_safe +
			nr_hardirq_unsafe * nr_hardirq_safe +
			nr_list_entries);

#ifdef CONFIG_PROVE_LOCKING
	seq_printf(m, " dependency chains:             %11lu [max: %lu]\n",
			lock_chain_count(), MAX_LOCKDEP_CHAINS);
	seq_printf(m, " dependency chain hlocks:       %11d [max: %lu]\n",
			nr_chain_hlocks, MAX_LOCKDEP_CHAIN_HLOCKS);
#endif

#ifdef CONFIG_TRACE_IRQFLAGS
	seq_printf(m, " in-hardirq chains:             %11u\n",
			nr_hardirq_chains);
	seq_printf(m, " in-softirq chains:             %11u\n",
			nr_softirq_chains);
#endif
	seq_printf(m, " in-process chains:             %11u\n",
			nr_process_chains);
	seq_printf(m, " stack-trace entries:           %11lu [max: %lu]\n",
			nr_stack_trace_entries, MAX_STACK_TRACE_ENTRIES);
#if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_PROVE_LOCKING)
	seq_printf(m, " number of stack traces:        %llu\n",
		   lockdep_stack_trace_count());
	seq_printf(m, " number of stack hash chains:   %llu\n",
		   lockdep_stack_hash_count());
#endif
	seq_printf(m, " combined max dependencies:     %11u\n",
			(nr_hardirq_chains + 1) *
			(nr_softirq_chains + 1) *
			(nr_process_chains + 1)
	);
	seq_printf(m, " hardirq-safe locks:            %11lu\n",
			nr_hardirq_safe);
	seq_printf(m, " hardirq-unsafe locks:          %11lu\n",
			nr_hardirq_unsafe);
	seq_printf(m, " softirq-safe locks:            %11lu\n",
			nr_softirq_safe);
	seq_printf(m, " softirq-unsafe locks:          %11lu\n",
			nr_softirq_unsafe);
	seq_printf(m, " irq-safe locks:                %11lu\n",
			nr_irq_safe);
	seq_printf(m, " irq-unsafe locks:              %11lu\n",
			nr_irq_unsafe);

	seq_printf(m, " hardirq-read-safe locks:       %11lu\n",
			nr_hardirq_read_safe);
	seq_printf(m, " hardirq-read-unsafe locks:     %11lu\n",
			nr_hardirq_read_unsafe);
	seq_printf(m, " softirq-read-safe locks:       %11lu\n",
			nr_softirq_read_safe);
	seq_printf(m, " softirq-read-unsafe locks:     %11lu\n",
			nr_softirq_read_unsafe);
	seq_printf(m, " irq-read-safe locks:           %11lu\n",
			nr_irq_read_safe);
	seq_printf(m, " irq-read-unsafe locks:         %11lu\n",
			nr_irq_read_unsafe);

	seq_printf(m, " uncategorized locks:           %11lu\n",
			nr_uncategorized);
	seq_printf(m, " unused locks:                  %11lu\n",
			nr_unused);
	seq_printf(m, " max locking depth:             %11u\n",
			max_lockdep_depth);
#ifdef CONFIG_PROVE_LOCKING
	seq_printf(m, " max bfs queue depth:           %11u\n",
			max_bfs_queue_depth);
#endif
	lockdep_stats_debug_show(m);
	seq_printf(m, " debug_locks:                   %11u\n",
			debug_locks);

	return 0;
}

#ifdef CONFIG_LOCK_STAT

struct lock_stat_data {
	struct lock_class *class;
	struct lock_class_stats stats;
};

struct lock_stat_seq {
	struct lock_stat_data *iter_end;
	struct lock_stat_data stats[MAX_LOCKDEP_KEYS];
};

/*
 * sort on absolute number of contentions
 */
static int lock_stat_cmp(const void *l, const void *r)
{
	const struct lock_stat_data *dl = l, *dr = r;
	unsigned long nl, nr;

	nl = dl->stats.read_waittime.nr + dl->stats.write_waittime.nr;
	nr = dr->stats.read_waittime.nr + dr->stats.write_waittime.nr;

	return nr - nl;
}

static void seq_line(struct seq_file *m, char c, int offset, int length)
{
	int i;

	for (i = 0; i < offset; i++)
		seq_puts(m, " ");
	for (i = 0; i < length; i++)
		seq_printf(m, "%c", c);
	seq_puts(m, "\n");
}

static void snprint_time(char *buf, size_t bufsiz, s64 nr)
{
	s64 div;
	s32 rem;

	nr += 5; /* for display rounding */
	div = div_s64_rem(nr, 1000, &rem);
	snprintf(buf, bufsiz, "%lld.%02d", (long long)div, (int)rem/10);
}

static void seq_time(struct seq_file *m, s64 time)
{
	char num[15];

	snprint_time(num, sizeof(num), time);
	seq_printf(m, " %14s", num);
}

static void seq_lock_time(struct seq_file *m, struct lock_time *lt)
{
	seq_printf(m, "%14lu", lt->nr);
	seq_time(m, lt->min);
	seq_time(m, lt->max);
	seq_time(m, lt->total);
	seq_time(m, lt->nr ? div_s64(lt->total, lt->nr) : 0);
}

static void seq_stats(struct seq_file *m, struct lock_stat_data *data)
{
	const struct lockdep_subclass_key *ckey;
	struct lock_class_stats *stats;
	struct lock_class *class;
	const char *cname;
	int i, namelen;
	char name[39];

	class = data->class;
	stats = &data->stats;

	namelen = 38;
	if (class->name_version > 1)
		namelen -= 2; /* XXX truncates versions > 9 */
	if (class->subclass)
		namelen -= 2;

	rcu_read_lock_sched();
	cname = rcu_dereference_sched(class->name);
	ckey  = rcu_dereference_sched(class->key);

	if (!cname && !ckey) {
		rcu_read_unlock_sched();
		return;

	} else if (!cname) {
		char str[KSYM_NAME_LEN];
		const char *key_name;

		key_name = __get_key_name(ckey, str);
		snprintf(name, namelen, "%s", key_name);
	} else {
		snprintf(name, namelen, "%s", cname);
	}
	rcu_read_unlock_sched();

	namelen = strlen(name);
	if (class->name_version > 1) {
		snprintf(name+namelen, 3, "#%d", class->name_version);
		namelen += 2;
	}
	if (class->subclass) {
		snprintf(name+namelen, 3, "/%d", class->subclass);
		namelen += 2;
	}

	if (stats->write_holdtime.nr) {
		if (stats->read_holdtime.nr)
			seq_printf(m, "%38s-W:", name);
		else
			seq_printf(m, "%40s:", name);

		seq_printf(m, "%14lu ", stats->bounces[bounce_contended_write]);
		seq_lock_time(m, &stats->write_waittime);
		seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_write]);
		seq_lock_time(m, &stats->write_holdtime);
		seq_puts(m, "\n");
	}

	if (stats->read_holdtime.nr) {
		seq_printf(m, "%38s-R:", name);
		seq_printf(m, "%14lu ", stats->bounces[bounce_contended_read]);
		seq_lock_time(m, &stats->read_waittime);
		seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_read]);
		seq_lock_time(m, &stats->read_holdtime);
		seq_puts(m, "\n");
	}

	if (stats->read_waittime.nr + stats->write_waittime.nr == 0)
		return;

	if (stats->read_holdtime.nr)
		namelen += 2;

	for (i = 0; i < LOCKSTAT_POINTS; i++) {
		char ip[32];

		if (class->contention_point[i] == 0)
			break;

		if (!i)
			seq_line(m, '-', 40-namelen, namelen);

		snprintf(ip, sizeof(ip), "[<%p>]",
				(void *)class->contention_point[i]);
		seq_printf(m, "%40s %14lu %29s %pS\n",
			   name, stats->contention_point[i],
			   ip, (void *)class->contention_point[i]);
	}
	for (i = 0; i < LOCKSTAT_POINTS; i++) {
		char ip[32];

		if (class->contending_point[i] == 0)
			break;

		if (!i)
			seq_line(m, '-', 40-namelen, namelen);

		snprintf(ip, sizeof(ip), "[<%p>]",
				(void *)class->contending_point[i]);
		seq_printf(m, "%40s %14lu %29s %pS\n",
			   name, stats->contending_point[i],
			   ip, (void *)class->contending_point[i]);
	}
	if (i) {
		seq_puts(m, "\n");
		seq_line(m, '.', 0, 40 + 1 + 12 * (14 + 1));
		seq_puts(m, "\n");
	}
}

static void seq_header(struct seq_file *m)
{
	seq_puts(m, "lock_stat version 0.4\n");

	if (unlikely(!debug_locks))
		seq_printf(m, "*WARNING* lock debugging disabled!! - possibly due to a lockdep warning\n");

	seq_line(m, '-', 0, 40 + 1 + 12 * (14 + 1));
	seq_printf(m, "%40s %14s %14s %14s %14s %14s %14s %14s %14s %14s %14s "
			"%14s %14s\n",
			"class name",
			"con-bounces",
			"contentions",
			"waittime-min",
			"waittime-max",
			"waittime-total",
			"waittime-avg",
			"acq-bounces",
			"acquisitions",
			"holdtime-min",
			"holdtime-max",
			"holdtime-total",
			"holdtime-avg");
	seq_line(m, '-', 0, 40 + 1 + 12 * (14 + 1));
	seq_printf(m, "\n");
}

static void *ls_start(struct seq_file *m, loff_t *pos)
{
	struct lock_stat_seq *data = m->private;
	struct lock_stat_data *iter;

	if (*pos == 0)
		return SEQ_START_TOKEN;

	iter = data->stats + (*pos - 1);
	if (iter >= data->iter_end)
		iter = NULL;

	return iter;
}

static void *ls_next(struct seq_file *m, void *v, loff_t *pos)
{
	(*pos)++;
	return ls_start(m, pos);
}

static void ls_stop(struct seq_file *m, void *v)
{
}

static int ls_show(struct seq_file *m, void *v)
{
	if (v == SEQ_START_TOKEN)
		seq_header(m);
	else
		seq_stats(m, v);

	return 0;
}

static const struct seq_operations lockstat_ops = {
	.start	= ls_start,
	.next	= ls_next,
	.stop	= ls_stop,
	.show	= ls_show,
};

static int lock_stat_open(struct inode *inode, struct file *file)
{
	int res;
	struct lock_class *class;
	struct lock_stat_seq *data = vmalloc(sizeof(struct lock_stat_seq));

	if (!data)
		return -ENOMEM;

	res = seq_open(file, &lockstat_ops);
	if (!res) {
		struct lock_stat_data *iter = data->stats;
		struct seq_file *m = file->private_data;

		list_for_each_entry(class, &all_lock_classes, lock_entry) {
			iter->class = class;
			iter->stats = lock_stats(class);
			iter++;
		}
		data->iter_end = iter;

		sort(data->stats, data->iter_end - data->stats,
				sizeof(struct lock_stat_data),
				lock_stat_cmp, NULL);

		m->private = data;
	} else
		vfree(data);

	return res;
}

static ssize_t lock_stat_write(struct file *file, const char __user *buf,
			       size_t count, loff_t *ppos)
{
	struct lock_class *class;
	char c;

	if (count) {
		if (get_user(c, buf))
			return -EFAULT;

		if (c != '0')
			return count;

		list_for_each_entry(class, &all_lock_classes, lock_entry)
			clear_lock_stats(class);
	}
	return count;
}

static int lock_stat_release(struct inode *inode, struct file *file)
{
	struct seq_file *seq = file->private_data;

	vfree(seq->private);
	return seq_release(inode, file);
}

static const struct file_operations proc_lock_stat_operations = {
	.open		= lock_stat_open,
	.write		= lock_stat_write,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= lock_stat_release,
};
#endif /* CONFIG_LOCK_STAT */

static int __init lockdep_proc_init(void)
{
	proc_create_seq("lockdep", S_IRUSR, NULL, &lockdep_ops);
#ifdef CONFIG_PROVE_LOCKING
	proc_create_seq("lockdep_chains", S_IRUSR, NULL, &lockdep_chains_ops);
#endif
	proc_create_single("lockdep_stats", S_IRUSR, NULL, lockdep_stats_show);
#ifdef CONFIG_LOCK_STAT
	proc_create("lock_stat", S_IRUSR | S_IWUSR, NULL,
		    &proc_lock_stat_operations);
#endif

	return 0;
}

__initcall(lockdep_proc_init);
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
a8f24a39 IM	2	/*
	3	* kernel/lockdep_proc.c
	4	*
	5	* Runtime locking correctness validator
	6	*
	7	* Started by Ingo Molnar:
	8	*
4b32d0a4	9	* Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
90eec103	10	* Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
a8f24a39 IM	11	*
	12	* Code for /proc/lockdep and /proc/lockdep_stats:
	13	*
	14	*/
9984de1a	15	#include <linux/export.h>
a8f24a39 IM	16	#include <linux/proc_fs.h>
	17	#include <linux/seq_file.h>
	18	#include <linux/kallsyms.h>
	19	#include <linux/debug_locks.h>
c46261de PZ	20	#include <linux/vmalloc.h>
c46261de PZ	21	#include <linux/sort.h>
7c0f6ba6	22	#include <linux/uaccess.h>
c46261de	23	#include <asm/div64.h>
a8f24a39 IM	24
	25	#include "lockdep_internals.h"
	26
	27	static void l_next(struct seq_file m, void v, loff_t pos)
	28	{
8109e1de	29	return seq_list_next(v, &all_lock_classes, pos);
a8f24a39 IM	30	}
	31
	32	static void l_start(struct seq_file m, loff_t *pos)
	33	{
8109e1de	34	return seq_list_start_head(&all_lock_classes, *pos);
a8f24a39 IM	35	}
	36
	37	static void l_stop(struct seq_file m, void v)
	38	{
	39	}
	40
068135e6 JB	41	static void print_name(struct seq_file m, struct lock_class class)
068135e6 JB	42	{
99fb4a12	43	char str[KSYM_NAME_LEN];
068135e6 JB	44	const char *name = class->name;
	45
	46	if (!name) {
	47	name = __get_key_name(class->key, str);
	48	seq_printf(m, "%s", name);
	49	} else{
	50	seq_printf(m, "%s", name);
	51	if (class->name_version > 1)
	52	seq_printf(m, "#%d", class->name_version);
	53	if (class->subclass)
	54	seq_printf(m, "/%d", class->subclass);
	55	}
	56	}
	57
a8f24a39 IM	58	static int l_show(struct seq_file m, void v)
a8f24a39 IM	59	{
8109e1de	60	struct lock_class *class = list_entry(v, struct lock_class, lock_entry);
068135e6	61	struct lock_list *entry;
f510b233	62	char usage[LOCK_USAGE_CHARS];
a8f24a39	63
8109e1de	64	if (v == &all_lock_classes) {
94c61c0a TP	65	seq_printf(m, "all lock classes:\n");
	66	return 0;
	67	}
	68
a8f24a39 IM	69	seq_printf(m, "%p", class->key);
a8f24a39 IM	70	#ifdef CONFIG_DEBUG_LOCKDEP
8ca2b56c	71	seq_printf(m, " OPS:%8ld", debug_class_ops_read(class));
a8f24a39	72	#endif
df60a844 SH	73	#ifdef CONFIG_PROVE_LOCKING
	74	seq_printf(m, " FD:%5ld", lockdep_count_forward_deps(class));
	75	seq_printf(m, " BD:%5ld", lockdep_count_backward_deps(class));
	76	#endif
a8f24a39	77
f510b233 PZ	78	get_usage_chars(class, usage);
f510b233 PZ	79	seq_printf(m, " %s", usage);
a8f24a39	80
068135e6 JB	81	seq_printf(m, ": ");
	82	print_name(m, class);
	83	seq_puts(m, "\n");
	84
	85	list_for_each_entry(entry, &class->locks_after, entry) {
	86	if (entry->distance == 1) {
2429e4ee	87	seq_printf(m, " -> [%p] ", entry->class->key);
068135e6 JB	88	print_name(m, entry->class);
	89	seq_puts(m, "\n");
	90	}
a8f24a39 IM	91	}
	92	seq_puts(m, "\n");
	93
	94	return 0;
	95	}
	96
15ad7cdc	97	static const struct seq_operations lockdep_ops = {
a8f24a39 IM	98	.start = l_start,
	99	.next = l_next,
	100	.stop = l_stop,
	101	.show = l_show,
	102	};
	103
cd1a28e8	104	#ifdef CONFIG_PROVE_LOCKING
443cd507 HY	105	static void lc_start(struct seq_file m, loff_t *pos)
443cd507 HY	106	{
2212684a BVA	107	if (*pos < 0)
	108	return NULL;
	109
443cd507 HY	110	if (*pos == 0)
	111	return SEQ_START_TOKEN;
	112
2212684a	113	return lock_chains + (*pos - 1);
443cd507 HY	114	}
443cd507 HY	115
12aac19d LZ	116	static void lc_next(struct seq_file m, void v, loff_t pos)
12aac19d LZ	117	{
2212684a	118	pos = lockdep_next_lockchain(pos - 1) + 1;
12aac19d LZ	119	return lc_start(m, pos);
	120	}
	121
443cd507 HY	122	static void lc_stop(struct seq_file m, void v)
	123	{
	124	}
	125
	126	static int lc_show(struct seq_file m, void v)
	127	{
	128	struct lock_chain *chain = v;
	129	struct lock_class *class;
	130	int i;
	131
	132	if (v == SEQ_START_TOKEN) {
75dd602a PZ	133	if (nr_chain_hlocks > MAX_LOCKDEP_CHAIN_HLOCKS)
75dd602a PZ	134	seq_printf(m, "(buggered) ");
443cd507 HY	135	seq_printf(m, "all lock chains:\n");
	136	return 0;
	137	}
	138
	139	seq_printf(m, "irq_context: %d\n", chain->irq_context);
	140
	141	for (i = 0; i < chain->depth; i++) {
	142	class = lock_chain_get_class(chain, i);
8bfe0298 RV	143	if (!class->key)
	144	continue;
	145
443cd507 HY	146	seq_printf(m, "[%p] ", class->key);
	147	print_name(m, class);
	148	seq_puts(m, "\n");
	149	}
	150	seq_puts(m, "\n");
	151
	152	return 0;
	153	}
	154
	155	static const struct seq_operations lockdep_chains_ops = {
	156	.start = lc_start,
	157	.next = lc_next,
	158	.stop = lc_stop,
	159	.show = lc_show,
	160	};
cd1a28e8	161	#endif /* CONFIG_PROVE_LOCKING */
443cd507	162
a8f24a39 IM	163	static void lockdep_stats_debug_show(struct seq_file *m)
	164	{
	165	#ifdef CONFIG_DEBUG_LOCKDEP
bd6d29c2 FW	166	unsigned long long hi1 = debug_atomic_read(hardirqs_on_events),
	167	hi2 = debug_atomic_read(hardirqs_off_events),
	168	hr1 = debug_atomic_read(redundant_hardirqs_on),
	169	hr2 = debug_atomic_read(redundant_hardirqs_off),
	170	si1 = debug_atomic_read(softirqs_on_events),
	171	si2 = debug_atomic_read(softirqs_off_events),
	172	sr1 = debug_atomic_read(redundant_softirqs_on),
	173	sr2 = debug_atomic_read(redundant_softirqs_off);
	174
	175	seq_printf(m, " chain lookup misses: %11llu\n",
	176	debug_atomic_read(chain_lookup_misses));
	177	seq_printf(m, " chain lookup hits: %11llu\n",
	178	debug_atomic_read(chain_lookup_hits));
	179	seq_printf(m, " cyclic checks: %11llu\n",
	180	debug_atomic_read(nr_cyclic_checks));
ae813308 PZ	181	seq_printf(m, " redundant checks: %11llu\n",
	182	debug_atomic_read(nr_redundant_checks));
	183	seq_printf(m, " redundant links: %11llu\n",
	184	debug_atomic_read(nr_redundant));
bd6d29c2 FW	185	seq_printf(m, " find-mask forwards checks: %11llu\n",
	186	debug_atomic_read(nr_find_usage_forwards_checks));
	187	seq_printf(m, " find-mask backwards checks: %11llu\n",
	188	debug_atomic_read(nr_find_usage_backwards_checks));
	189
	190	seq_printf(m, " hardirq on events: %11llu\n", hi1);
	191	seq_printf(m, " hardirq off events: %11llu\n", hi2);
	192	seq_printf(m, " redundant hardirq ons: %11llu\n", hr1);
	193	seq_printf(m, " redundant hardirq offs: %11llu\n", hr2);
	194	seq_printf(m, " softirq on events: %11llu\n", si1);
	195	seq_printf(m, " softirq off events: %11llu\n", si2);
	196	seq_printf(m, " redundant softirq ons: %11llu\n", sr1);
	197	seq_printf(m, " redundant softirq offs: %11llu\n", sr2);
a8f24a39 IM	198	#endif
	199	}
	200
	201	static int lockdep_stats_show(struct seq_file m, void v)
	202	{
a8f24a39 IM	203	unsigned long nr_unused = 0, nr_uncategorized = 0,
	204	nr_irq_safe = 0, nr_irq_unsafe = 0,
	205	nr_softirq_safe = 0, nr_softirq_unsafe = 0,
	206	nr_hardirq_safe = 0, nr_hardirq_unsafe = 0,
	207	nr_irq_read_safe = 0, nr_irq_read_unsafe = 0,
	208	nr_softirq_read_safe = 0, nr_softirq_read_unsafe = 0,
	209	nr_hardirq_read_safe = 0, nr_hardirq_read_unsafe = 0,
dec29608	210	sum_forward_deps = 0;
a8f24a39	211
68d41d8c	212	#ifdef CONFIG_PROVE_LOCKING
68037aa7 AB	213	struct lock_class *class;
68037aa7 AB	214
a8f24a39 IM	215	list_for_each_entry(class, &all_lock_classes, lock_entry) {
	216
	217	if (class->usage_mask == 0)
	218	nr_unused++;
	219	if (class->usage_mask == LOCKF_USED)
	220	nr_uncategorized++;
	221	if (class->usage_mask & LOCKF_USED_IN_IRQ)
	222	nr_irq_safe++;
4fc95e86	223	if (class->usage_mask & LOCKF_ENABLED_IRQ)
a8f24a39 IM	224	nr_irq_unsafe++;
	225	if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ)
	226	nr_softirq_safe++;
4fc95e86	227	if (class->usage_mask & LOCKF_ENABLED_SOFTIRQ)
a8f24a39 IM	228	nr_softirq_unsafe++;
	229	if (class->usage_mask & LOCKF_USED_IN_HARDIRQ)
	230	nr_hardirq_safe++;
4fc95e86	231	if (class->usage_mask & LOCKF_ENABLED_HARDIRQ)
a8f24a39 IM	232	nr_hardirq_unsafe++;
	233	if (class->usage_mask & LOCKF_USED_IN_IRQ_READ)
	234	nr_irq_read_safe++;
4fc95e86	235	if (class->usage_mask & LOCKF_ENABLED_IRQ_READ)
a8f24a39 IM	236	nr_irq_read_unsafe++;
	237	if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ_READ)
	238	nr_softirq_read_safe++;
4fc95e86	239	if (class->usage_mask & LOCKF_ENABLED_SOFTIRQ_READ)
a8f24a39 IM	240	nr_softirq_read_unsafe++;
	241	if (class->usage_mask & LOCKF_USED_IN_HARDIRQ_READ)
	242	nr_hardirq_read_safe++;
4fc95e86	243	if (class->usage_mask & LOCKF_ENABLED_HARDIRQ_READ)
a8f24a39 IM	244	nr_hardirq_read_unsafe++;
a8f24a39 IM	245
419ca3f1	246	sum_forward_deps += lockdep_count_forward_deps(class);
a8f24a39	247	}
501b9ebf	248	#ifdef CONFIG_DEBUG_LOCKDEP
bd6d29c2	249	DEBUG_LOCKS_WARN_ON(debug_atomic_read(nr_unused_locks) != nr_unused);
68d41d8c YD	250	#endif
68d41d8c YD	251
a8f24a39 IM	252	#endif
	253	seq_printf(m, " lock-classes: %11lu [max: %lu]\n",
	254	nr_lock_classes, MAX_LOCKDEP_KEYS);
	255	seq_printf(m, " direct dependencies: %11lu [max: %lu]\n",
	256	nr_list_entries, MAX_LOCKDEP_ENTRIES);
	257	seq_printf(m, " indirect dependencies: %11lu\n",
	258	sum_forward_deps);
	259
	260	/*
	261	* Total number of dependencies:
	262	*
	263	* All irq-safe locks may nest inside irq-unsafe locks,
	264	* plus all the other known dependencies:
	265	*/
	266	seq_printf(m, " all direct dependencies: %11lu\n",
	267	nr_irq_unsafe * nr_irq_safe +
	268	nr_hardirq_unsafe * nr_hardirq_safe +
	269	nr_list_entries);
	270
8e18257d	271	#ifdef CONFIG_PROVE_LOCKING
a8f24a39	272	seq_printf(m, " dependency chains: %11lu [max: %lu]\n",
2212684a	273	lock_chain_count(), MAX_LOCKDEP_CHAINS);
443cd507	274	seq_printf(m, " dependency chain hlocks: %11d [max: %lu]\n",
cd1a28e8	275	nr_chain_hlocks, MAX_LOCKDEP_CHAIN_HLOCKS);
8e18257d	276	#endif
a8f24a39 IM	277
	278	#ifdef CONFIG_TRACE_IRQFLAGS
	279	seq_printf(m, " in-hardirq chains: %11u\n",
	280	nr_hardirq_chains);
	281	seq_printf(m, " in-softirq chains: %11u\n",
	282	nr_softirq_chains);
	283	#endif
	284	seq_printf(m, " in-process chains: %11u\n",
	285	nr_process_chains);
	286	seq_printf(m, " stack-trace entries: %11lu [max: %lu]\n",
	287	nr_stack_trace_entries, MAX_STACK_TRACE_ENTRIES);
8c779229 BVA	288	#if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_PROVE_LOCKING)
	289	seq_printf(m, " number of stack traces: %llu\n",
	290	lockdep_stack_trace_count());
	291	seq_printf(m, " number of stack hash chains: %llu\n",
	292	lockdep_stack_hash_count());
	293	#endif
a8f24a39 IM	294	seq_printf(m, " combined max dependencies: %11u\n",
	295	(nr_hardirq_chains + 1) *
	296	(nr_softirq_chains + 1) *
	297	(nr_process_chains + 1)
	298	);
	299	seq_printf(m, " hardirq-safe locks: %11lu\n",
	300	nr_hardirq_safe);
	301	seq_printf(m, " hardirq-unsafe locks: %11lu\n",
	302	nr_hardirq_unsafe);
	303	seq_printf(m, " softirq-safe locks: %11lu\n",
	304	nr_softirq_safe);
	305	seq_printf(m, " softirq-unsafe locks: %11lu\n",
	306	nr_softirq_unsafe);
	307	seq_printf(m, " irq-safe locks: %11lu\n",
	308	nr_irq_safe);
	309	seq_printf(m, " irq-unsafe locks: %11lu\n",
	310	nr_irq_unsafe);
	311
	312	seq_printf(m, " hardirq-read-safe locks: %11lu\n",
	313	nr_hardirq_read_safe);
	314	seq_printf(m, " hardirq-read-unsafe locks: %11lu\n",
	315	nr_hardirq_read_unsafe);
	316	seq_printf(m, " softirq-read-safe locks: %11lu\n",
	317	nr_softirq_read_safe);
	318	seq_printf(m, " softirq-read-unsafe locks: %11lu\n",
	319	nr_softirq_read_unsafe);
	320	seq_printf(m, " irq-read-safe locks: %11lu\n",
	321	nr_irq_read_safe);
	322	seq_printf(m, " irq-read-unsafe locks: %11lu\n",
	323	nr_irq_read_unsafe);
	324
	325	seq_printf(m, " uncategorized locks: %11lu\n",
	326	nr_uncategorized);
	327	seq_printf(m, " unused locks: %11lu\n",
	328	nr_unused);
	329	seq_printf(m, " max locking depth: %11u\n",
	330	max_lockdep_depth);
bbfa2622	331	#ifdef CONFIG_PROVE_LOCKING
12f3dfd0 ML	332	seq_printf(m, " max bfs queue depth: %11u\n",
12f3dfd0 ML	333	max_bfs_queue_depth);
bbfa2622	334	#endif
a8f24a39 IM	335	lockdep_stats_debug_show(m);
	336	seq_printf(m, " debug_locks: %11u\n",
	337	debug_locks);
	338
	339	return 0;
	340	}
	341
c46261de PZ	342	#ifdef CONFIG_LOCK_STAT
	343
	344	struct lock_stat_data {
	345	struct lock_class *class;
	346	struct lock_class_stats stats;
	347	};
	348
	349	struct lock_stat_seq {
c46261de PZ	350	struct lock_stat_data *iter_end;
	351	struct lock_stat_data stats[MAX_LOCKDEP_KEYS];
	352	};
	353
	354	/*
	355	* sort on absolute number of contentions
	356	*/
	357	static int lock_stat_cmp(const void l, const void r)
	358	{
	359	const struct lock_stat_data dl = l, dr = r;
	360	unsigned long nl, nr;
	361
	362	nl = dl->stats.read_waittime.nr + dl->stats.write_waittime.nr;
	363	nr = dr->stats.read_waittime.nr + dr->stats.write_waittime.nr;
	364
	365	return nr - nl;
	366	}
	367
	368	static void seq_line(struct seq_file *m, char c, int offset, int length)
	369	{
	370	int i;
	371
	372	for (i = 0; i < offset; i++)
	373	seq_puts(m, " ");
	374	for (i = 0; i < length; i++)
	375	seq_printf(m, "%c", c);
	376	seq_puts(m, "\n");
	377	}
	378
	379	static void snprint_time(char *buf, size_t bufsiz, s64 nr)
	380	{
6918bc5c PZ	381	s64 div;
6918bc5c PZ	382	s32 rem;
c46261de	383
2189459d	384	nr += 5; /* for display rounding */
6918bc5c PZ	385	div = div_s64_rem(nr, 1000, &rem);
6918bc5c PZ	386	snprintf(buf, bufsiz, "%lld.%02d", (long long)div, (int)rem/10);
c46261de PZ	387	}
	388
	389	static void seq_time(struct seq_file *m, s64 time)
	390	{
	391	char num[15];
	392
	393	snprint_time(num, sizeof(num), time);
	394	seq_printf(m, " %14s", num);
	395	}
	396
	397	static void seq_lock_time(struct seq_file m, struct lock_time lt)
	398	{
	399	seq_printf(m, "%14lu", lt->nr);
	400	seq_time(m, lt->min);
	401	seq_time(m, lt->max);
	402	seq_time(m, lt->total);
838cc7b4	403	seq_time(m, lt->nr ? div_s64(lt->total, lt->nr) : 0);
c46261de PZ	404	}
	405
	406	static void seq_stats(struct seq_file m, struct lock_stat_data data)
	407	{
364f6afc	408	const struct lockdep_subclass_key *ckey;
c46261de	409	struct lock_class_stats *stats;
cee34d88 PZ	410	struct lock_class *class;
cee34d88 PZ	411	const char *cname;
c46261de	412	int i, namelen;
cee34d88	413	char name[39];
c46261de PZ	414
	415	class = data->class;
	416	stats = &data->stats;
	417
d38e1d5a PZ	418	namelen = 38;
	419	if (class->name_version > 1)
	420	namelen -= 2; /* XXX truncates versions > 9 */
	421	if (class->subclass)
	422	namelen -= 2;
	423
cee34d88 PZ	424	rcu_read_lock_sched();
	425	cname = rcu_dereference_sched(class->name);
	426	ckey = rcu_dereference_sched(class->key);
	427
	428	if (!cname && !ckey) {
	429	rcu_read_unlock_sched();
	430	return;
	431
	432	} else if (!cname) {
d38e1d5a PZ	433	char str[KSYM_NAME_LEN];
	434	const char *key_name;
	435
cee34d88	436	key_name = __get_key_name(ckey, str);
d38e1d5a PZ	437	snprintf(name, namelen, "%s", key_name);
d38e1d5a PZ	438	} else {
cee34d88	439	snprintf(name, namelen, "%s", cname);
d38e1d5a	440	}
cee34d88 PZ	441	rcu_read_unlock_sched();
cee34d88 PZ	442
c46261de	443	namelen = strlen(name);
d38e1d5a PZ	444	if (class->name_version > 1) {
	445	snprintf(name+namelen, 3, "#%d", class->name_version);
	446	namelen += 2;
	447	}
	448	if (class->subclass) {
	449	snprintf(name+namelen, 3, "/%d", class->subclass);
	450	namelen += 2;
	451	}
c46261de PZ	452
	453	if (stats->write_holdtime.nr) {
	454	if (stats->read_holdtime.nr)
	455	seq_printf(m, "%38s-W:", name);
	456	else
	457	seq_printf(m, "%40s:", name);
	458
96645678	459	seq_printf(m, "%14lu ", stats->bounces[bounce_contended_write]);
c46261de	460	seq_lock_time(m, &stats->write_waittime);
96645678	461	seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_write]);
c46261de PZ	462	seq_lock_time(m, &stats->write_holdtime);
	463	seq_puts(m, "\n");
	464	}
	465
	466	if (stats->read_holdtime.nr) {
	467	seq_printf(m, "%38s-R:", name);
96645678	468	seq_printf(m, "%14lu ", stats->bounces[bounce_contended_read]);
c46261de	469	seq_lock_time(m, &stats->read_waittime);
96645678	470	seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_read]);
c46261de PZ	471	seq_lock_time(m, &stats->read_holdtime);
	472	seq_puts(m, "\n");
	473	}
	474
	475	if (stats->read_waittime.nr + stats->write_waittime.nr == 0)
	476	return;
	477
	478	if (stats->read_holdtime.nr)
	479	namelen += 2;
	480
c7e78cff	481	for (i = 0; i < LOCKSTAT_POINTS; i++) {
c46261de PZ	482	char ip[32];
	483
	484	if (class->contention_point[i] == 0)
	485	break;
	486
	487	if (!i)
	488	seq_line(m, '-', 40-namelen, namelen);
	489
c46261de PZ	490	snprintf(ip, sizeof(ip), "[<%p>]",
c46261de PZ	491	(void *)class->contention_point[i]);
3cf9b85b JP	492	seq_printf(m, "%40s %14lu %29s %pS\n",
	493	name, stats->contention_point[i],
	494	ip, (void *)class->contention_point[i]);
c46261de	495	}
c7e78cff	496	for (i = 0; i < LOCKSTAT_POINTS; i++) {
c7e78cff PZ	497	char ip[32];
	498
	499	if (class->contending_point[i] == 0)
	500	break;
	501
	502	if (!i)
	503	seq_line(m, '-', 40-namelen, namelen);
	504
c7e78cff PZ	505	snprintf(ip, sizeof(ip), "[<%p>]",
c7e78cff PZ	506	(void *)class->contending_point[i]);
3cf9b85b JP	507	seq_printf(m, "%40s %14lu %29s %pS\n",
	508	name, stats->contending_point[i],
	509	ip, (void *)class->contending_point[i]);
c7e78cff	510	}
c46261de PZ	511	if (i) {
c46261de PZ	512	seq_puts(m, "\n");
1232e380	513	seq_line(m, '.', 0, 40 + 1 + 12 * (14 + 1));
c46261de PZ	514	seq_puts(m, "\n");
	515	}
	516	}
	517
	518	static void seq_header(struct seq_file *m)
	519	{
1232e380	520	seq_puts(m, "lock_stat version 0.4\n");
9833f8cb PZ	521
	522	if (unlikely(!debug_locks))
	523	seq_printf(m, "WARNING lock debugging disabled!! - possibly due to a lockdep warning\n");
	524
1232e380 DB	525	seq_line(m, '-', 0, 40 + 1 + 12 * (14 + 1));
1232e380 DB	526	seq_printf(m, "%40s %14s %14s %14s %14s %14s %14s %14s %14s %14s %14s "
96645678	527	"%14s %14s\n",
c46261de	528	"class name",
96645678	529	"con-bounces",
c46261de PZ	530	"contentions",
	531	"waittime-min",
	532	"waittime-max",
	533	"waittime-total",
1232e380	534	"waittime-avg",
96645678	535	"acq-bounces",
c46261de PZ	536	"acquisitions",
	537	"holdtime-min",
	538	"holdtime-max",
1232e380 DB	539	"holdtime-total",
	540	"holdtime-avg");
	541	seq_line(m, '-', 0, 40 + 1 + 12 * (14 + 1));
c46261de PZ	542	seq_printf(m, "\n");
	543	}
	544
	545	static void ls_start(struct seq_file m, loff_t *pos)
	546	{
	547	struct lock_stat_seq *data = m->private;
96004bb2	548	struct lock_stat_data *iter;
c46261de	549
94c61c0a TP	550	if (*pos == 0)
94c61c0a TP	551	return SEQ_START_TOKEN;
c46261de	552
96004bb2 LZ	553	iter = data->stats + (*pos - 1);
	554	if (iter >= data->iter_end)
	555	iter = NULL;
4b32d0a4	556
96004bb2	557	return iter;
c46261de PZ	558	}
	559
	560	static void ls_next(struct seq_file m, void v, loff_t pos)
	561	{
c46261de	562	(*pos)++;
96004bb2	563	return ls_start(m, pos);
c46261de PZ	564	}
	565
	566	static void ls_stop(struct seq_file m, void v)
	567	{
	568	}
	569
	570	static int ls_show(struct seq_file m, void v)
	571	{
94c61c0a TP	572	if (v == SEQ_START_TOKEN)
	573	seq_header(m);
	574	else
	575	seq_stats(m, v);
c46261de	576
c46261de PZ	577	return 0;
	578	}
	579
88e9d34c	580	static const struct seq_operations lockstat_ops = {
c46261de PZ	581	.start = ls_start,
	582	.next = ls_next,
	583	.stop = ls_stop,
	584	.show = ls_show,
	585	};
	586
	587	static int lock_stat_open(struct inode inode, struct file file)
	588	{
	589	int res;
	590	struct lock_class *class;
	591	struct lock_stat_seq *data = vmalloc(sizeof(struct lock_stat_seq));
	592
	593	if (!data)
	594	return -ENOMEM;
	595
	596	res = seq_open(file, &lockstat_ops);
	597	if (!res) {
	598	struct lock_stat_data *iter = data->stats;
	599	struct seq_file *m = file->private_data;
	600
c46261de PZ	601	list_for_each_entry(class, &all_lock_classes, lock_entry) {
	602	iter->class = class;
	603	iter->stats = lock_stats(class);
	604	iter++;
	605	}
	606	data->iter_end = iter;
	607
96004bb2	608	sort(data->stats, data->iter_end - data->stats,
c46261de PZ	609	sizeof(struct lock_stat_data),
	610	lock_stat_cmp, NULL);
	611
	612	m->private = data;
	613	} else
	614	vfree(data);
	615
	616	return res;
	617	}
	618
	619	static ssize_t lock_stat_write(struct file file, const char __user buf,
	620	size_t count, loff_t *ppos)
	621	{
	622	struct lock_class *class;
	623	char c;
	624
	625	if (count) {
	626	if (get_user(c, buf))
	627	return -EFAULT;
	628
	629	if (c != '0')
	630	return count;
	631
	632	list_for_each_entry(class, &all_lock_classes, lock_entry)
	633	clear_lock_stats(class);
	634	}
	635	return count;
	636	}
	637
	638	static int lock_stat_release(struct inode inode, struct file file)
	639	{
	640	struct seq_file *seq = file->private_data;
	641
	642	vfree(seq->private);
c46261de PZ	643	return seq_release(inode, file);
	644	}
	645
	646	static const struct file_operations proc_lock_stat_operations = {
	647	.open = lock_stat_open,
	648	.write = lock_stat_write,
	649	.read = seq_read,
	650	.llseek = seq_lseek,
	651	.release = lock_stat_release,
	652	};
	653	#endif /* CONFIG_LOCK_STAT */
	654
a8f24a39 IM	655	static int __init lockdep_proc_init(void)
a8f24a39 IM	656	{
fddda2b7	657	proc_create_seq("lockdep", S_IRUSR, NULL, &lockdep_ops);
cd1a28e8	658	#ifdef CONFIG_PROVE_LOCKING
fddda2b7	659	proc_create_seq("lockdep_chains", S_IRUSR, NULL, &lockdep_chains_ops);
cd1a28e8	660	#endif
3f3942ac	661	proc_create_single("lockdep_stats", S_IRUSR, NULL, lockdep_stats_show);
c46261de	662	#ifdef CONFIG_LOCK_STAT
9795447f LZ	663	proc_create("lock_stat", S_IRUSR \| S_IWUSR, NULL,
9795447f LZ	664	&proc_lock_stat_operations);
c46261de PZ	665	#endif
c46261de PZ	666
a8f24a39 IM	667	return 0;
	668	}
	669
	670	__initcall(lockdep_proc_init);
	671