Commit b2fef076 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

perf_counter tools: Sample and display frequency adjustment changes 



To allow the debugging of frequency-adjusting counters, sample
those adjustments and display them in perf report -D.

Acked-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 6a24ed6c

Documentation/perf_counter/builtin-record.c

+1 −1
Original line number Diff line number Diff line
@@ -347,7 +347,7 @@ static void create_counter(int counter, int cpu, pid_t pid) 
	memset(&attr, 0, sizeof(attr));

	attr.config		= event_id[counter];

	attr.sample_period	= event_count[counter];

	attr.sample_type	= PERF_SAMPLE_IP | PERF_SAMPLE_TID;

	attr.sample_type	= PERF_SAMPLE_IP | PERF_SAMPLE_TID | PERF_SAMPLE_PERIOD;

	attr.freq		= freq;

	attr.mmap		= track;

	attr.comm		= track;

Documentation/perf_counter/builtin-report.c

+33 −6
Original line number Diff line number Diff line
@@ -69,12 +69,20 @@ struct fork_event { 
	__u32 pid, ppid;

};



struct period_event {

	struct perf_event_header header;

	__u64 time;

	__u64 id;

	__u64 sample_period;

};



typedef union event_union {

	struct perf_event_header	header;

	struct ip_event			ip;

	struct mmap_event		mmap;

	struct comm_event		comm;

	struct fork_event		fork;

	struct period_event		period;

} event_t;



static LIST_HEAD(dsos);
@@ -1052,6 +1060,19 @@ process_fork_event(event_t *event, unsigned long offset, unsigned long head) 
	return 0;

}



static int

process_period_event(event_t *event, unsigned long offset, unsigned long head)

{

	dprintf("%p [%p]: PERF_EVENT_PERIOD: time:%Ld, id:%Ld: period:%Ld\n",

		(void *)(offset + head),

		(void *)(long)(event->header.size),

		event->period.time,

		event->period.id,

		event->period.sample_period);



	return 0;

}



static int

process_event(event_t *event, unsigned long offset, unsigned long head)

{
@@ -1068,11 +1089,12 @@ process_event(event_t *event, unsigned long offset, unsigned long head) 
	case PERF_EVENT_FORK:

		return process_fork_event(event, offset, head);



	case PERF_EVENT_PERIOD:

		return process_period_event(event, offset, head);

	/*

	 * We dont process them right now but they are fine:

	 */



	case PERF_EVENT_PERIOD:

	case PERF_EVENT_THROTTLE:

	case PERF_EVENT_UNTHROTTLE:

		return 0;
@@ -1157,6 +1179,11 @@ more: 


	size = event->header.size;



	dprintf("%p [%p]: event: %d\n",

			(void *)(offset + head),

			(void *)(long)event->header.size,

			event->header.type);



	if (!size || process_event(event, offset, head) < 0) {



		dprintf("%p [%p]: skipping unknown header type: %d\n",

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