Commit 00ee22c2 authored by Mahendran Ganesh's avatar Mahendran Ganesh Committed by Rafael J. Wysocki
Browse files

PM / wakeup: Use seq_open() to show wakeup stats 



single_open() interface requires that the whole output must
fit into a single buffer. This will lead to timeout when
system memory is not in a good situation.

This patch use seq_open() to show wakeup stats. This method
need only one page, so timeout will not be observed.

Signed-off-by: default avatarGanesh Mahendran <opensource.ganesh@gmail.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 7f817ba9

drivers/base/power/wakeup.c

+59 −16
Original line number Diff line number Diff line
@@ -1029,32 +1029,75 @@ static int print_wakeup_source_stats(struct seq_file *m, 
	return 0;

}



/**

 * wakeup_sources_stats_show - Print wakeup sources statistics information.

 * @m: seq_file to print the statistics into.

 */

static int wakeup_sources_stats_show(struct seq_file *m, void *unused)

static void *wakeup_sources_stats_seq_start(struct seq_file *m,

					loff_t *pos)

{

	struct wakeup_source *ws;

	int srcuidx;

	loff_t n = *pos;

	int *srcuidx = m->private;



	if (n == 0) {

		seq_puts(m, "name\t\tactive_count\tevent_count\twakeup_count\t"

			"expire_count\tactive_since\ttotal_time\tmax_time\t"

			"last_change\tprevent_suspend_time\n");

	}



	srcuidx = srcu_read_lock(&wakeup_srcu);

	list_for_each_entry_rcu(ws, &wakeup_sources, entry)

		print_wakeup_source_stats(m, ws);

	srcu_read_unlock(&wakeup_srcu, srcuidx);

	*srcuidx = srcu_read_lock(&wakeup_srcu);

	list_for_each_entry_rcu(ws, &wakeup_sources, entry) {

		if (n-- <= 0)

			return ws;

	}



	print_wakeup_source_stats(m, &deleted_ws);

	return NULL;

}



static void *wakeup_sources_stats_seq_next(struct seq_file *m,

					void *v, loff_t *pos)

{

	struct wakeup_source *ws = v;

	struct wakeup_source *next_ws = NULL;



	++(*pos);



	list_for_each_entry_continue_rcu(ws, &wakeup_sources, entry) {

		next_ws = ws;

		break;

	}



	return next_ws;

}



static void wakeup_sources_stats_seq_stop(struct seq_file *m, void *v)

{

	int *srcuidx = m->private;



	srcu_read_unlock(&wakeup_srcu, *srcuidx);

}



/**

 * wakeup_sources_stats_seq_show - Print wakeup sources statistics information.

 * @m: seq_file to print the statistics into.

 * @v: wakeup_source of each iteration

 */

static int wakeup_sources_stats_seq_show(struct seq_file *m, void *v)

{

	struct wakeup_source *ws = v;



	print_wakeup_source_stats(m, ws);



	return 0;

}



static const struct seq_operations wakeup_sources_stats_seq_ops = {

	.start = wakeup_sources_stats_seq_start,

	.next  = wakeup_sources_stats_seq_next,

	.stop  = wakeup_sources_stats_seq_stop,

	.show  = wakeup_sources_stats_seq_show,

};



static int wakeup_sources_stats_open(struct inode *inode, struct file *file)

{

	return single_open(file, wakeup_sources_stats_show, NULL);

	return seq_open_private(file, &wakeup_sources_stats_seq_ops, sizeof(int));

}



static const struct file_operations wakeup_sources_stats_fops = {
@@ -1062,7 +1105,7 @@ static const struct file_operations wakeup_sources_stats_fops = { 
	.open = wakeup_sources_stats_open,

	.read = seq_read,

	.llseek = seq_lseek,

	.release = single_release,

	.release = seq_release_private,

};



static int __init wakeup_sources_debugfs_init(void)

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