[net-next-2.6.git] / kernel / lockdep_proc.c

/*
 * 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 <pzijlstr@redhat.com>
 *
 * Code for /proc/lockdep and /proc/lockdep_stats:
 *
 */
#include <linux/module.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 <asm/uaccess.h>
#include <asm/div64.h>

#include "lockdep_internals.h"

static void *l_next(struct seq_file *m, void *v, loff_t *pos)
{
	struct lock_class *class = v;

	(*pos)++;

	if (class->lock_entry.next != &all_lock_classes)
		class = list_entry(class->lock_entry.next, struct lock_class,
				  lock_entry);
	else
		class = NULL;
	m->private = class;

	return class;
}

static void *l_start(struct seq_file *m, loff_t *pos)
{
	struct lock_class *class = m->private;

	if (&class->lock_entry == all_lock_classes.next)
		seq_printf(m, "all lock classes:\n");

	return class;
}

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

static unsigned long count_forward_deps(struct lock_class *class)
{
	struct lock_list *entry;
	unsigned long ret = 1;

	/*
	 * Recurse this class's dependency list:
	 */
	list_for_each_entry(entry, &class->locks_after, entry)
		ret += count_forward_deps(entry->class);

	return ret;
}

static unsigned long count_backward_deps(struct lock_class *class)
{
	struct lock_list *entry;
	unsigned long ret = 1;

	/*
	 * Recurse this class's dependency list:
	 */
	list_for_each_entry(entry, &class->locks_before, entry)
		ret += count_backward_deps(entry->class);

	return ret;
}

static void print_name(struct seq_file *m, struct lock_class *class)
{
	char str[128];
	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)
{
	unsigned long nr_forward_deps, nr_backward_deps;
	struct lock_class *class = m->private;
	struct lock_list *entry;
	char c1, c2, c3, c4;

	seq_printf(m, "%p", class->key);
#ifdef CONFIG_DEBUG_LOCKDEP
	seq_printf(m, " OPS:%8ld", class->ops);
#endif
	nr_forward_deps = count_forward_deps(class);
	seq_printf(m, " FD:%5ld", nr_forward_deps);

	nr_backward_deps = count_backward_deps(class);
	seq_printf(m, " BD:%5ld", nr_backward_deps);

	get_usage_chars(class, &c1, &c2, &c3, &c4);
	seq_printf(m, " %c%c%c%c", c1, c2, c3, c4);

	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);
			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,
};

static int lockdep_open(struct inode *inode, struct file *file)
{
	int res = seq_open(file, &lockdep_ops);
	if (!res) {
		struct seq_file *m = file->private_data;

		if (!list_empty(&all_lock_classes))
			m->private = list_entry(all_lock_classes.next,
					struct lock_class, lock_entry);
		else
			m->private = NULL;
	}
	return res;
}

static const struct file_operations proc_lockdep_operations = {
	.open		= lockdep_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};

static void lockdep_stats_debug_show(struct seq_file *m)
{
#ifdef CONFIG_DEBUG_LOCKDEP
	unsigned int 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:           %11u\n",
		debug_atomic_read(&chain_lookup_misses));
	seq_printf(m, " chain lookup hits:             %11u\n",
		debug_atomic_read(&chain_lookup_hits));
	seq_printf(m, " cyclic checks:                 %11u\n",
		debug_atomic_read(&nr_cyclic_checks));
	seq_printf(m, " cyclic-check recursions:       %11u\n",
		debug_atomic_read(&nr_cyclic_check_recursions));
	seq_printf(m, " find-mask forwards checks:     %11u\n",
		debug_atomic_read(&nr_find_usage_forwards_checks));
	seq_printf(m, " find-mask forwards recursions: %11u\n",
		debug_atomic_read(&nr_find_usage_forwards_recursions));
	seq_printf(m, " find-mask backwards checks:    %11u\n",
		debug_atomic_read(&nr_find_usage_backwards_checks));
	seq_printf(m, " find-mask backwards recursions:%11u\n",
		debug_atomic_read(&nr_find_usage_backwards_recursions));

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

static int lockdep_stats_show(struct seq_file *m, void *v)
{
	struct lock_class *class;
	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, factor = 0;

	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_IRQS)
			nr_irq_unsafe++;
		if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ)
			nr_softirq_safe++;
		if (class->usage_mask & LOCKF_ENABLED_SOFTIRQS)
			nr_softirq_unsafe++;
		if (class->usage_mask & LOCKF_USED_IN_HARDIRQ)
			nr_hardirq_safe++;
		if (class->usage_mask & LOCKF_ENABLED_HARDIRQS)
			nr_hardirq_unsafe++;
		if (class->usage_mask & LOCKF_USED_IN_IRQ_READ)
			nr_irq_read_safe++;
		if (class->usage_mask & LOCKF_ENABLED_IRQS_READ)
			nr_irq_read_unsafe++;
		if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ_READ)
			nr_softirq_read_safe++;
		if (class->usage_mask & LOCKF_ENABLED_SOFTIRQS_READ)
			nr_softirq_read_unsafe++;
		if (class->usage_mask & LOCKF_USED_IN_HARDIRQ_READ)
			nr_hardirq_read_safe++;
		if (class->usage_mask & LOCKF_ENABLED_HARDIRQS_READ)
			nr_hardirq_read_unsafe++;

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

	/*
	 * Estimated factor between direct and indirect
	 * dependencies:
	 */
	if (nr_list_entries)
		factor = sum_forward_deps / nr_list_entries;

#ifdef CONFIG_PROVE_LOCKING
	seq_printf(m, " dependency chains:             %11lu [max: %lu]\n",
			nr_lock_chains, MAX_LOCKDEP_CHAINS);
#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);
	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);
	seq_printf(m, " max recursion depth:           %11u\n",
			max_recursion_depth);
	lockdep_stats_debug_show(m);
	seq_printf(m, " debug_locks:                   %11u\n",
			debug_locks);

	return 0;
}

static int lockdep_stats_open(struct inode *inode, struct file *file)
{
	return single_open(file, lockdep_stats_show, NULL);
}

static const struct file_operations proc_lockdep_stats_operations = {
	.open		= lockdep_stats_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};

#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;
	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)
{
	unsigned long rem;

	rem = do_div(nr, 1000); /* XXX: do_div_signed */
	snprintf(buf, bufsiz, "%lld.%02d", (long long)nr, ((int)rem+5)/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);
}

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

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

	snprintf(name, 38, "%s", class->name);
	namelen = strlen(name);

	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 < ARRAY_SIZE(class->contention_point); i++) {
		char sym[KSYM_SYMBOL_LEN];
		char ip[32];

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

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

		sprint_symbol(sym, class->contention_point[i]);
		snprintf(ip, sizeof(ip), "[<%p>]",
				(void *)class->contention_point[i]);
		seq_printf(m, "%40s %14lu %29s %s\n", name,
				stats->contention_point[i],
				ip, sym);
	}
	if (i) {
		seq_puts(m, "\n");
		seq_line(m, '.', 0, 40 + 1 + 10 * (14 + 1));
		seq_puts(m, "\n");
	}
}

static void seq_header(struct seq_file *m)
{
	seq_printf(m, "lock_stat version 0.2\n");
	seq_line(m, '-', 0, 40 + 1 + 10 * (14 + 1));
	seq_printf(m, "%40s %14s %14s %14s %14s %14s %14s %14s %14s "
			"%14s %14s\n",
			"class name",
			"con-bounces",
			"contentions",
			"waittime-min",
			"waittime-max",
			"waittime-total",
			"acq-bounces",
			"acquisitions",
			"holdtime-min",
			"holdtime-max",
			"holdtime-total");
	seq_line(m, '-', 0, 40 + 1 + 10 * (14 + 1));
	seq_printf(m, "\n");
}

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

	if (data->iter == data->stats)
		seq_header(m);

	if (data->iter == data->iter_end)
		data->iter = NULL;

	return data->iter;
}

static void *ls_next(struct seq_file *m, void *v, loff_t *pos)
{
	struct lock_stat_seq *data = m->private;

	(*pos)++;

	data->iter = v;
	data->iter++;
	if (data->iter == data->iter_end)
		data->iter = NULL;

	return data->iter;
}

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

static int ls_show(struct seq_file *m, void *v)
{
	struct lock_stat_seq *data = m->private;

	seq_stats(m, data->iter);
	return 0;
}

static 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;

		data->iter = iter;
		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->iter,
				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);
	seq->private = NULL;
	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)
{
	struct proc_dir_entry *entry;

	entry = create_proc_entry("lockdep", S_IRUSR, NULL);
	if (entry)
		entry->proc_fops = &proc_lockdep_operations;

	entry = create_proc_entry("lockdep_stats", S_IRUSR, NULL);
	if (entry)
		entry->proc_fops = &proc_lockdep_stats_operations;

#ifdef CONFIG_LOCK_STAT
	entry = create_proc_entry("lock_stat", S_IRUSR, NULL);
	if (entry)
		entry->proc_fops = &proc_lock_stat_operations;
#endif

	return 0;
}

__initcall(lockdep_proc_init);
Commit	Line	Data
a8f24a39 IM	1	/*
	2	* kernel/lockdep_proc.c
	3	*
	4	* Runtime locking correctness validator
	5	*
	6	* Started by Ingo Molnar:
	7	*
4b32d0a4 PZ	8	* Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
4b32d0a4 PZ	9	* Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
a8f24a39 IM	10	*
	11	* Code for /proc/lockdep and /proc/lockdep_stats:
	12	*
	13	*/
a8f24a39 IM	14	#include <linux/module.h>
	15	#include <linux/proc_fs.h>
	16	#include <linux/seq_file.h>
	17	#include <linux/kallsyms.h>
	18	#include <linux/debug_locks.h>
c46261de PZ	19	#include <linux/vmalloc.h>
	20	#include <linux/sort.h>
	21	#include <asm/uaccess.h>
	22	#include <asm/div64.h>
a8f24a39 IM	23
	24	#include "lockdep_internals.h"
	25
	26	static void l_next(struct seq_file m, void v, loff_t pos)
	27	{
	28	struct lock_class *class = v;
	29
	30	(*pos)++;
	31
	32	if (class->lock_entry.next != &all_lock_classes)
	33	class = list_entry(class->lock_entry.next, struct lock_class,
	34	lock_entry);
	35	else
	36	class = NULL;
	37	m->private = class;
	38
	39	return class;
	40	}
	41
	42	static void l_start(struct seq_file m, loff_t *pos)
	43	{
	44	struct lock_class *class = m->private;
	45
	46	if (&class->lock_entry == all_lock_classes.next)
	47	seq_printf(m, "all lock classes:\n");
	48
	49	return class;
	50	}
	51
	52	static void l_stop(struct seq_file m, void v)
	53	{
	54	}
	55
	56	static unsigned long count_forward_deps(struct lock_class *class)
	57	{
	58	struct lock_list *entry;
	59	unsigned long ret = 1;
	60
	61	/*
	62	* Recurse this class's dependency list:
	63	*/
	64	list_for_each_entry(entry, &class->locks_after, entry)
	65	ret += count_forward_deps(entry->class);
	66
	67	return ret;
	68	}
	69
	70	static unsigned long count_backward_deps(struct lock_class *class)
	71	{
	72	struct lock_list *entry;
	73	unsigned long ret = 1;
	74
	75	/*
	76	* Recurse this class's dependency list:
	77	*/
	78	list_for_each_entry(entry, &class->locks_before, entry)
	79	ret += count_backward_deps(entry->class);
	80
	81	return ret;
	82	}
	83
068135e6 JB	84	static void print_name(struct seq_file m, struct lock_class class)
	85	{
	86	char str[128];
	87	const char *name = class->name;
	88
	89	if (!name) {
	90	name = __get_key_name(class->key, str);
	91	seq_printf(m, "%s", name);
	92	} else{
	93	seq_printf(m, "%s", name);
	94	if (class->name_version > 1)
	95	seq_printf(m, "#%d", class->name_version);
	96	if (class->subclass)
	97	seq_printf(m, "/%d", class->subclass);
	98	}
	99	}
	100
a8f24a39 IM	101	static int l_show(struct seq_file m, void v)
	102	{
	103	unsigned long nr_forward_deps, nr_backward_deps;
	104	struct lock_class *class = m->private;
068135e6 JB	105	struct lock_list *entry;
068135e6 JB	106	char c1, c2, c3, c4;
a8f24a39 IM	107
	108	seq_printf(m, "%p", class->key);
	109	#ifdef CONFIG_DEBUG_LOCKDEP
	110	seq_printf(m, " OPS:%8ld", class->ops);
	111	#endif
	112	nr_forward_deps = count_forward_deps(class);
	113	seq_printf(m, " FD:%5ld", nr_forward_deps);
	114
	115	nr_backward_deps = count_backward_deps(class);
	116	seq_printf(m, " BD:%5ld", nr_backward_deps);
	117
	118	get_usage_chars(class, &c1, &c2, &c3, &c4);
	119	seq_printf(m, " %c%c%c%c", c1, c2, c3, c4);
	120
068135e6 JB	121	seq_printf(m, ": ");
	122	print_name(m, class);
	123	seq_puts(m, "\n");
	124
	125	list_for_each_entry(entry, &class->locks_after, entry) {
	126	if (entry->distance == 1) {
	127	seq_printf(m, " -> [%p] ", entry->class);
	128	print_name(m, entry->class);
	129	seq_puts(m, "\n");
	130	}
a8f24a39 IM	131	}
	132	seq_puts(m, "\n");
	133
	134	return 0;
	135	}
	136
15ad7cdc	137	static const struct seq_operations lockdep_ops = {
a8f24a39 IM	138	.start = l_start,
	139	.next = l_next,
	140	.stop = l_stop,
	141	.show = l_show,
	142	};
	143
	144	static int lockdep_open(struct inode inode, struct file file)
	145	{
	146	int res = seq_open(file, &lockdep_ops);
	147	if (!res) {
	148	struct seq_file *m = file->private_data;
	149
	150	if (!list_empty(&all_lock_classes))
	151	m->private = list_entry(all_lock_classes.next,
	152	struct lock_class, lock_entry);
	153	else
	154	m->private = NULL;
	155	}
	156	return res;
	157	}
	158
15ad7cdc	159	static const struct file_operations proc_lockdep_operations = {
a8f24a39 IM	160	.open = lockdep_open,
	161	.read = seq_read,
	162	.llseek = seq_lseek,
	163	.release = seq_release,
	164	};
	165
	166	static void lockdep_stats_debug_show(struct seq_file *m)
	167	{
	168	#ifdef CONFIG_DEBUG_LOCKDEP
	169	unsigned int hi1 = debug_atomic_read(&hardirqs_on_events),
	170	hi2 = debug_atomic_read(&hardirqs_off_events),
	171	hr1 = debug_atomic_read(&redundant_hardirqs_on),
	172	hr2 = debug_atomic_read(&redundant_hardirqs_off),
	173	si1 = debug_atomic_read(&softirqs_on_events),
	174	si2 = debug_atomic_read(&softirqs_off_events),
	175	sr1 = debug_atomic_read(&redundant_softirqs_on),
	176	sr2 = debug_atomic_read(&redundant_softirqs_off);
	177
	178	seq_printf(m, " chain lookup misses: %11u\n",
	179	debug_atomic_read(&chain_lookup_misses));
	180	seq_printf(m, " chain lookup hits: %11u\n",
	181	debug_atomic_read(&chain_lookup_hits));
	182	seq_printf(m, " cyclic checks: %11u\n",
	183	debug_atomic_read(&nr_cyclic_checks));
	184	seq_printf(m, " cyclic-check recursions: %11u\n",
	185	debug_atomic_read(&nr_cyclic_check_recursions));
	186	seq_printf(m, " find-mask forwards checks: %11u\n",
	187	debug_atomic_read(&nr_find_usage_forwards_checks));
	188	seq_printf(m, " find-mask forwards recursions: %11u\n",
	189	debug_atomic_read(&nr_find_usage_forwards_recursions));
	190	seq_printf(m, " find-mask backwards checks: %11u\n",
	191	debug_atomic_read(&nr_find_usage_backwards_checks));
	192	seq_printf(m, " find-mask backwards recursions:%11u\n",
	193	debug_atomic_read(&nr_find_usage_backwards_recursions));
	194
	195	seq_printf(m, " hardirq on events: %11u\n", hi1);
	196	seq_printf(m, " hardirq off events: %11u\n", hi2);
	197	seq_printf(m, " redundant hardirq ons: %11u\n", hr1);
	198	seq_printf(m, " redundant hardirq offs: %11u\n", hr2);
	199	seq_printf(m, " softirq on events: %11u\n", si1);
	200	seq_printf(m, " softirq off events: %11u\n", si2);
	201	seq_printf(m, " redundant softirq ons: %11u\n", sr1);
	202	seq_printf(m, " redundant softirq offs: %11u\n", sr2);
	203	#endif
	204	}
	205
	206	static int lockdep_stats_show(struct seq_file m, void v)
	207	{
	208	struct lock_class *class;
	209	unsigned long nr_unused = 0, nr_uncategorized = 0,
	210	nr_irq_safe = 0, nr_irq_unsafe = 0,
	211	nr_softirq_safe = 0, nr_softirq_unsafe = 0,
	212	nr_hardirq_safe = 0, nr_hardirq_unsafe = 0,
	213	nr_irq_read_safe = 0, nr_irq_read_unsafe = 0,
	214	nr_softirq_read_safe = 0, nr_softirq_read_unsafe = 0,
	215	nr_hardirq_read_safe = 0, nr_hardirq_read_unsafe = 0,
	216	sum_forward_deps = 0, factor = 0;
	217
	218	list_for_each_entry(class, &all_lock_classes, lock_entry) {
	219
	220	if (class->usage_mask == 0)
	221	nr_unused++;
	222	if (class->usage_mask == LOCKF_USED)
	223	nr_uncategorized++;
224	if (class->usage_mask & LOCKF_USED_IN_IRQ)
225	nr_irq_safe++;
226	if (class->usage_mask & LOCKF_ENABLED_IRQS)
227	nr_irq_unsafe++;
228	if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ)
229	nr_softirq_safe++;
230	if (class->usage_mask & LOCKF_ENABLED_SOFTIRQS)
231	nr_softirq_unsafe++;
232	if (class->usage_mask & LOCKF_USED_IN_HARDIRQ)
233	nr_hardirq_safe++;
234	if (class->usage_mask & LOCKF_ENABLED_HARDIRQS)
235	nr_hardirq_unsafe++;
236	if (class->usage_mask & LOCKF_USED_IN_IRQ_READ)
237	nr_irq_read_safe++;
238	if (class->usage_mask & LOCKF_ENABLED_IRQS_READ)
239	nr_irq_read_unsafe++;
240	if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ_READ)
241	nr_softirq_read_safe++;
242	if (class->usage_mask & LOCKF_ENABLED_SOFTIRQS_READ)
243	nr_softirq_read_unsafe++;
244	if (class->usage_mask & LOCKF_USED_IN_HARDIRQ_READ)
245	nr_hardirq_read_safe++;
246	if (class->usage_mask & LOCKF_ENABLED_HARDIRQS_READ)
247	nr_hardirq_read_unsafe++;
248
249	sum_forward_deps += count_forward_deps(class);
250	}
501b9ebf	251	#ifdef CONFIG_DEBUG_LOCKDEP
a8f24a39 IM	252	DEBUG_LOCKS_WARN_ON(debug_atomic_read(&nr_unused_locks) != nr_unused);
	253	#endif
	254	seq_printf(m, " lock-classes: %11lu [max: %lu]\n",
	255	nr_lock_classes, MAX_LOCKDEP_KEYS);
	256	seq_printf(m, " direct dependencies: %11lu [max: %lu]\n",
	257	nr_list_entries, MAX_LOCKDEP_ENTRIES);
	258	seq_printf(m, " indirect dependencies: %11lu\n",
	259	sum_forward_deps);
	260
	261	/*
	262	* Total number of dependencies:
	263	*
	264	* All irq-safe locks may nest inside irq-unsafe locks,
	265	* plus all the other known dependencies:
	266	*/
	267	seq_printf(m, " all direct dependencies: %11lu\n",
	268	nr_irq_unsafe * nr_irq_safe +
	269	nr_hardirq_unsafe * nr_hardirq_safe +
	270	nr_list_entries);
	271
	272	/*
	273	* Estimated factor between direct and indirect
	274	* dependencies:
	275	*/
	276	if (nr_list_entries)
	277	factor = sum_forward_deps / nr_list_entries;
	278
8e18257d	279	#ifdef CONFIG_PROVE_LOCKING
a8f24a39 IM	280	seq_printf(m, " dependency chains: %11lu [max: %lu]\n",
a8f24a39 IM	281	nr_lock_chains, MAX_LOCKDEP_CHAINS);
8e18257d	282	#endif
a8f24a39 IM	283
	284	#ifdef CONFIG_TRACE_IRQFLAGS
	285	seq_printf(m, " in-hardirq chains: %11u\n",
	286	nr_hardirq_chains);
	287	seq_printf(m, " in-softirq chains: %11u\n",
	288	nr_softirq_chains);
	289	#endif
	290	seq_printf(m, " in-process chains: %11u\n",
	291	nr_process_chains);
	292	seq_printf(m, " stack-trace entries: %11lu [max: %lu]\n",
	293	nr_stack_trace_entries, MAX_STACK_TRACE_ENTRIES);
	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);
	331	seq_printf(m, " max recursion depth: %11u\n",
	332	max_recursion_depth);
	333	lockdep_stats_debug_show(m);
	334	seq_printf(m, " debug_locks: %11u\n",
	335	debug_locks);
	336
	337	return 0;
	338	}
	339
	340	static int lockdep_stats_open(struct inode inode, struct file file)
	341	{
	342	return single_open(file, lockdep_stats_show, NULL);
	343	}
	344
15ad7cdc	345	static const struct file_operations proc_lockdep_stats_operations = {
a8f24a39 IM	346	.open = lockdep_stats_open,
	347	.read = seq_read,
	348	.llseek = seq_lseek,
	349	.release = seq_release,
	350	};
	351
c46261de PZ	352	#ifdef CONFIG_LOCK_STAT
	353
	354	struct lock_stat_data {
	355	struct lock_class *class;
	356	struct lock_class_stats stats;
	357	};
	358
	359	struct lock_stat_seq {
	360	struct lock_stat_data *iter;
	361	struct lock_stat_data *iter_end;
	362	struct lock_stat_data stats[MAX_LOCKDEP_KEYS];
	363	};
	364
	365	/*
	366	* sort on absolute number of contentions
	367	*/
	368	static int lock_stat_cmp(const void l, const void r)
	369	{
	370	const struct lock_stat_data dl = l, dr = r;
	371	unsigned long nl, nr;
	372
	373	nl = dl->stats.read_waittime.nr + dl->stats.write_waittime.nr;
	374	nr = dr->stats.read_waittime.nr + dr->stats.write_waittime.nr;
	375
	376	return nr - nl;
	377	}
	378
	379	static void seq_line(struct seq_file *m, char c, int offset, int length)
	380	{
	381	int i;
	382
	383	for (i = 0; i < offset; i++)
	384	seq_puts(m, " ");
	385	for (i = 0; i < length; i++)
	386	seq_printf(m, "%c", c);
	387	seq_puts(m, "\n");
	388	}
	389
	390	static void snprint_time(char *buf, size_t bufsiz, s64 nr)
	391	{
	392	unsigned long rem;
	393
	394	rem = do_div(nr, 1000); /* XXX: do_div_signed */
	395	snprintf(buf, bufsiz, "%lld.%02d", (long long)nr, ((int)rem+5)/10);
	396	}
	397
	398	static void seq_time(struct seq_file *m, s64 time)
	399	{
	400	char num[15];
	401
	402	snprint_time(num, sizeof(num), time);
	403	seq_printf(m, " %14s", num);
	404	}
	405
	406	static void seq_lock_time(struct seq_file m, struct lock_time lt)
	407	{
	408	seq_printf(m, "%14lu", lt->nr);
	409	seq_time(m, lt->min);
	410	seq_time(m, lt->max);
	411	seq_time(m, lt->total);
	412	}
	413
	414	static void seq_stats(struct seq_file m, struct lock_stat_data data)
	415	{
416	char name[39];
417	struct lock_class *class;
418	struct lock_class_stats *stats;
419	int i, namelen;
420
421	class = data->class;
422	stats = &data->stats;
423
424	snprintf(name, 38, "%s", class->name);
425	namelen = strlen(name);
426
427	if (stats->write_holdtime.nr) {
428	if (stats->read_holdtime.nr)
429	seq_printf(m, "%38s-W:", name);
430	else
431	seq_printf(m, "%40s:", name);
432
96645678	433	seq_printf(m, "%14lu ", stats->bounces[bounce_contended_write]);
c46261de	434	seq_lock_time(m, &stats->write_waittime);
96645678	435	seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_write]);
c46261de PZ	436	seq_lock_time(m, &stats->write_holdtime);
	437	seq_puts(m, "\n");
	438	}
	439
	440	if (stats->read_holdtime.nr) {
	441	seq_printf(m, "%38s-R:", name);
96645678	442	seq_printf(m, "%14lu ", stats->bounces[bounce_contended_read]);
c46261de	443	seq_lock_time(m, &stats->read_waittime);
96645678	444	seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_read]);
c46261de PZ	445	seq_lock_time(m, &stats->read_holdtime);
	446	seq_puts(m, "\n");
	447	}
	448
	449	if (stats->read_waittime.nr + stats->write_waittime.nr == 0)
	450	return;
	451
	452	if (stats->read_holdtime.nr)
	453	namelen += 2;
	454
	455	for (i = 0; i < ARRAY_SIZE(class->contention_point); i++) {
	456	char sym[KSYM_SYMBOL_LEN];
	457	char ip[32];
	458
	459	if (class->contention_point[i] == 0)
	460	break;
	461
	462	if (!i)
	463	seq_line(m, '-', 40-namelen, namelen);
	464
	465	sprint_symbol(sym, class->contention_point[i]);
	466	snprintf(ip, sizeof(ip), "[<%p>]",
	467	(void *)class->contention_point[i]);
	468	seq_printf(m, "%40s %14lu %29s %s\n", name,
	469	stats->contention_point[i],
	470	ip, sym);
	471	}
	472	if (i) {
	473	seq_puts(m, "\n");
96645678	474	seq_line(m, '.', 0, 40 + 1 + 10 * (14 + 1));
c46261de PZ	475	seq_puts(m, "\n");
	476	}
	477	}
	478
	479	static void seq_header(struct seq_file *m)
	480	{
96645678 PZ	481	seq_printf(m, "lock_stat version 0.2\n");
	482	seq_line(m, '-', 0, 40 + 1 + 10 * (14 + 1));
	483	seq_printf(m, "%40s %14s %14s %14s %14s %14s %14s %14s %14s "
	484	"%14s %14s\n",
c46261de	485	"class name",
96645678	486	"con-bounces",
c46261de PZ	487	"contentions",
	488	"waittime-min",
	489	"waittime-max",
	490	"waittime-total",
96645678	491	"acq-bounces",
c46261de PZ	492	"acquisitions",
	493	"holdtime-min",
	494	"holdtime-max",
	495	"holdtime-total");
96645678	496	seq_line(m, '-', 0, 40 + 1 + 10 * (14 + 1));
c46261de PZ	497	seq_printf(m, "\n");
	498	}
	499
	500	static void ls_start(struct seq_file m, loff_t *pos)
	501	{
	502	struct lock_stat_seq *data = m->private;
	503
	504	if (data->iter == data->stats)
	505	seq_header(m);
	506
4b32d0a4 PZ	507	if (data->iter == data->iter_end)
	508	data->iter = NULL;
	509
c46261de PZ	510	return data->iter;
	511	}
	512
	513	static void ls_next(struct seq_file m, void v, loff_t pos)
	514	{
	515	struct lock_stat_seq *data = m->private;
	516
	517	(*pos)++;
	518
	519	data->iter = v;
	520	data->iter++;
	521	if (data->iter == data->iter_end)
	522	data->iter = NULL;
	523
	524	return data->iter;
	525	}
	526
	527	static void ls_stop(struct seq_file m, void v)
	528	{
	529	}
	530
	531	static int ls_show(struct seq_file m, void v)
	532	{
	533	struct lock_stat_seq *data = m->private;
	534
	535	seq_stats(m, data->iter);
	536	return 0;
	537	}
	538
	539	static struct seq_operations lockstat_ops = {
	540	.start = ls_start,
	541	.next = ls_next,
	542	.stop = ls_stop,
	543	.show = ls_show,
	544	};
	545
	546	static int lock_stat_open(struct inode inode, struct file file)
	547	{
	548	int res;
	549	struct lock_class *class;
	550	struct lock_stat_seq *data = vmalloc(sizeof(struct lock_stat_seq));
	551
	552	if (!data)
	553	return -ENOMEM;
	554
	555	res = seq_open(file, &lockstat_ops);
	556	if (!res) {
	557	struct lock_stat_data *iter = data->stats;
	558	struct seq_file *m = file->private_data;
	559
	560	data->iter = iter;
	561	list_for_each_entry(class, &all_lock_classes, lock_entry) {
	562	iter->class = class;
	563	iter->stats = lock_stats(class);
	564	iter++;
	565	}
	566	data->iter_end = iter;
	567
	568	sort(data->stats, data->iter_end - data->iter,
	569	sizeof(struct lock_stat_data),
	570	lock_stat_cmp, NULL);
	571
	572	m->private = data;
	573	} else
574	vfree(data);
575
576	return res;
577	}
578
579	static ssize_t lock_stat_write(struct file file, const char __user buf,
580	size_t count, loff_t *ppos)
581	{
582	struct lock_class *class;
583	char c;
584
585	if (count) {
586	if (get_user(c, buf))
587	return -EFAULT;
588
589	if (c != '0')
590	return count;
591
592	list_for_each_entry(class, &all_lock_classes, lock_entry)
593	clear_lock_stats(class);
594	}
595	return count;
596	}
597
598	static int lock_stat_release(struct inode inode, struct file file)
599	{
600	struct seq_file *seq = file->private_data;
601
602	vfree(seq->private);
603	seq->private = NULL;
604	return seq_release(inode, file);
605	}
606
607	static const struct file_operations proc_lock_stat_operations = {
608	.open = lock_stat_open,
609	.write = lock_stat_write,
610	.read = seq_read,
611	.llseek = seq_lseek,
612	.release = lock_stat_release,
613	};
614	#endif /* CONFIG_LOCK_STAT */
615
a8f24a39 IM	616	static int __init lockdep_proc_init(void)
	617	{
	618	struct proc_dir_entry *entry;
	619
	620	entry = create_proc_entry("lockdep", S_IRUSR, NULL);
	621	if (entry)
	622	entry->proc_fops = &proc_lockdep_operations;
	623
	624	entry = create_proc_entry("lockdep_stats", S_IRUSR, NULL);
	625	if (entry)
	626	entry->proc_fops = &proc_lockdep_stats_operations;
	627
c46261de PZ	628	#ifdef CONFIG_LOCK_STAT
	629	entry = create_proc_entry("lock_stat", S_IRUSR, NULL);
	630	if (entry)
	631	entry->proc_fops = &proc_lock_stat_operations;
	632	#endif
	633
a8f24a39 IM	634	return 0;
	635	}
	636
	637	__initcall(lockdep_proc_init);
	638