Commit cc203d24 authored by Guillaume Chazarain's avatar Guillaume Chazarain Committed by Ingo Molnar
Browse files

sched: monitor clock underflows in /proc/sched_debug 



We monitor clock overflows, let's also monitor clock underflows.

Signed-off-by: default avatarGuillaume Chazarain <guichaz@yahoo.fr>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 782daeee

kernel/sched.c

+4 −2
Original line number Diff line number Diff line
@@ -465,7 +465,7 @@ struct rq { 
	u64 clock, prev_clock_raw;

	s64 clock_max_delta;



	unsigned int clock_warps, clock_overflows;

	unsigned int clock_warps, clock_overflows, clock_underflows;

	u64 idle_clock;

	unsigned int clock_deep_idle_events;

	u64 tick_timestamp;
@@ -3736,8 +3736,10 @@ void scheduler_tick(void) 
	/*

	 * Let rq->clock advance by at least TICK_NSEC:

	 */

	if (unlikely(rq->clock < next_tick))

	if (unlikely(rq->clock < next_tick)) {

		rq->clock = next_tick;

		rq->clock_underflows++;

	}

	rq->tick_timestamp = rq->clock;

	update_cpu_load(rq);

	curr->sched_class->task_tick(rq, curr, 0);

kernel/sched_debug.c

+1 −0
Original line number Diff line number Diff line
@@ -179,6 +179,7 @@ static void print_cpu(struct seq_file *m, int cpu) 
	PN(prev_clock_raw);

	P(clock_warps);

	P(clock_overflows);

	P(clock_underflows);

	P(clock_deep_idle_events);

	PN(clock_max_delta);

	P(cpu_load[0]);