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: Ganesh Mahendran <opensource.ganesh@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Mahendran Ganesh 2018-04-25 18:59:31 +08:00 committed by Rafael J. Wysocki
parent 7f817ba942
commit 00ee22c289
1 changed files with 59 additions and 16 deletions

View File

@ -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;
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");
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)