Commit e220d2dc authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar
Browse files

perf_counter: Fix dynamic irq_period logging 



We call perf_adjust_freq() from perf_counter_task_tick() which
is is called under the rq->lock causing lock recursion.
However, it's no longer required to be called under the
rq->lock, so remove it from under it.

Also, fix up some related comments.

Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090523163012.476197912@chello.nl>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent c6eb1384

include/linux/perf_counter.h

+1 −0
Original line number Diff line number Diff line
@@ -260,6 +260,7 @@ enum perf_event_type { 
	/*

	 * struct {

	 * 	struct perf_event_header	header;

	 * 	u64				time;

	 * 	u64				irq_period;

	 * };

	 */

kernel/perf_counter.c

+2 −1
Original line number Diff line number Diff line
@@ -2559,7 +2559,8 @@ void perf_counter_munmap(unsigned long addr, unsigned long len, 
}



/*

 *

 * Log irq_period changes so that analyzing tools can re-normalize the

 * event flow.

 */



static void perf_log_period(struct perf_counter *counter, u64 period)

kernel/sched.c

+2 −1
Original line number Diff line number Diff line
@@ -4875,9 +4875,10 @@ void scheduler_tick(void) 
	update_rq_clock(rq);

	update_cpu_load(rq);

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

	perf_counter_task_tick(curr, cpu);

	spin_unlock(&rq->lock);



	perf_counter_task_tick(curr, cpu);



#ifdef CONFIG_SMP

	rq->idle_at_tick = idle_cpu(cpu);

	trigger_load_balance(rq, cpu);