Commit 905365f4 authored by Jin Yao's avatar Jin Yao Committed by Arnaldo Carvalho de Melo
Browse files

perf stat: Save aggr value to first member of prev_raw_counts 



To collect the overall statistics for interval mode, we copy the counts
from evsel->prev_raw_counts to evsel->counts.

For AGGR_GLOBAL mode, because the perf_stat_process_counter creates aggr
values from per cpu values, but the per cpu values are 0, so the
calculated aggr values will be always 0.

This patch uses a trick that saves the previous aggr value to the first
member of perf_counts, then aggr calculation in process_counter_values
can work correctly for AGGR_GLOBAL.

 v6:
 ---
 Add comments in perf_evlist__save_aggr_prev_raw_counts.

Signed-off-by: default avatarJin Yao <yao.jin@linux.intel.com>
Reviewed-by: default avatarJiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200520042737.24160-5-yao.jin@linux.intel.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 297767ac

tools/perf/util/stat.c

+20 −0
Original line number Diff line number Diff line
@@ -249,6 +249,26 @@ void perf_evlist__copy_prev_raw_counts(struct evlist *evlist) 
		perf_evsel__copy_prev_raw_counts(evsel);

}



void perf_evlist__save_aggr_prev_raw_counts(struct evlist *evlist)

{

	struct evsel *evsel;



	/*

	 * To collect the overall statistics for interval mode,

	 * we copy the counts from evsel->prev_raw_counts to

	 * evsel->counts. The perf_stat_process_counter creates

	 * aggr values from per cpu values, but the per cpu values

	 * are 0 for AGGR_GLOBAL. So we use a trick that saves the

	 * previous aggr value to the first member of perf_counts,

	 * then aggr calculation in process_counter_values can work

	 * correctly.

	 */

	evlist__for_each_entry(evlist, evsel) {

		*perf_counts(evsel->prev_raw_counts, 0, 0) =

			evsel->prev_raw_counts->aggr;

	}

}



static void zero_per_pkg(struct evsel *counter)

{

	if (counter->per_pkg_mask)

tools/perf/util/stat.h

+1 −0
Original line number Diff line number Diff line
@@ -199,6 +199,7 @@ void perf_evlist__free_stats(struct evlist *evlist); 
void perf_evlist__reset_stats(struct evlist *evlist);

void perf_evlist__reset_prev_raw_counts(struct evlist *evlist);

void perf_evlist__copy_prev_raw_counts(struct evlist *evlist);

void perf_evlist__save_aggr_prev_raw_counts(struct evlist *evlist);



int perf_stat_process_counter(struct perf_stat_config *config,

			      struct evsel *counter);