lockdep_proc.c

来自「Kernel code of linux kernel」· C语言 代码 · 共 747 行 · 第 1/2 页

	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	= single_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;

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

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;

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

	if (!class->name) {
		char str[KSYM_NAME_LEN];
		const char *key_name;

		key_name = __get_key_name(class->key, str);
		snprintf(name, namelen, "%s", key_name);
	} else {
		snprintf(name, namelen, "%s", class->name);
	}
	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 < 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 (*pos == 0)
		return SEQ_START_TOKEN;

	data->iter = data->stats + *pos;
	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)++;

	if (v == SEQ_START_TOKEN)
		data->iter = data->stats;
	else {
		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)
{
	if (v == SEQ_START_TOKEN)
		seq_header(m);
	else
		seq_stats(m, v);

	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)
{
	proc_create("lockdep", S_IRUSR, NULL, &proc_lockdep_operations);
#ifdef CONFIG_PROVE_LOCKING
	proc_create("lockdep_chains", S_IRUSR, NULL,
		    &proc_lockdep_chains_operations);
#endif
	proc_create("lockdep_stats", S_IRUSR, NULL,
		    &proc_lockdep_stats_operations);

#ifdef CONFIG_LOCK_STAT
	proc_create("lock_stat", S_IRUSR, NULL, &proc_lock_stat_operations);
#endif

	return 0;
}

__initcall(lockdep_proc_init);