timer stats: Add a 'Collection: active/inactive' line to timer usage statistics

We can enable/disable timer statistics collection via:

  echo [1|0] > /proc/timers_stats

and it would be nice if apps had the ability to check
what the current collection status is.

This patch adds a 'Collection: active/inactive' line to display the
current timer collection status.

Also bump up the timer stats version to v0.3.

Signed-off-by: Dong Zhu <[email protected]>
Cc: John Stultz <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
[ Improved the changelog and the code. ]
Signed-off-by: Ingo Molnar <[email protected]>
This commit is contained in:
Dong Zhu 2013-10-10 15:56:18 +08:00 • committed by Ingo Molnar
commit 2cb763614c

View file

@ -298,15 +298,15 @@ static int tstats_show(struct seq_file *m, void *v)
period = ktime_to_timespec(time);
ms = period.tv_nsec / 1000000;
seq_puts(m, "Timer Stats Version: v0.2\n");
seq_puts(m, "Timer Stats Version: v0.3\n");
seq_printf(m, "Sample period: %ld.%03ld s\n", period.tv_sec, ms);
if (atomic_read(&overflow_count))
seq_printf(m, "Overflow: %d entries\n",
atomic_read(&overflow_count));
seq_printf(m, "Overflow: %d entries\n", atomic_read(&overflow_count));
seq_printf(m, "Collection: %s\n", timer_stats_active ? "active" : "inactive");
for (i = 0; i < nr_entries; i++) {
entry = entries + i;
if (entry->timer_flag & TIMER_STATS_FLAG_DEFERRABLE) {
if (entry->timer_flag & TIMER_STATS_FLAG_DEFERRABLE) {
seq_printf(m, "%4luD, %5d %-16s ",
entry->count, entry->pid, entry->comm);
} else {