Commit 9d2dc632 authored by Ian Rogers's avatar Ian Rogers Committed by Arnaldo Carvalho de Melo
Browse files

perf evlist: Remove nr_groups 



Maintaining the number of groups during event parsing is problematic
and since changing to sort/regroup events can only be computed by a
linear pass over the evlist. As the value is generally only used in
tests, rather than hold it in a variable compute it by passing over
the evlist when necessary.

This change highlights that libpfm's counting of groups with a single
entry disagreed with regular event parsing. The libpfm tests are
updated accordingly.

Signed-off-by: default avatarIan Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Florian Fischer <florian.fischer@muhq.space>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kim Phillips <kim.phillips@amd.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Steinar H. Gunderson <sesse@google.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Link: https://lore.kernel.org/r/20230312021543.3060328-2-irogers@google.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent e733f87e

tools/lib/perf/evlist.c

+17 −1
Original line number Diff line number Diff line
@@ -703,7 +703,23 @@ void perf_evlist__set_leader(struct perf_evlist *evlist) 
		struct perf_evsel *first = list_entry(evlist->entries.next,

						struct perf_evsel, node);



		evlist->nr_groups = evlist->nr_entries > 1 ? 1 : 0;

		__perf_evlist__set_leader(&evlist->entries, first);

	}

}



int perf_evlist__nr_groups(struct perf_evlist *evlist)

{

	struct perf_evsel *evsel;

	int nr_groups = 0;



	perf_evlist__for_each_evsel(evlist, evsel) {

		/*

		 * evsels by default have a nr_members of 1, and they are their

		 * own leader. If the nr_members is >1 then this is an

		 * indication of a group.

		 */

		if (evsel->leader == evsel && evsel->nr_members > 1)

			nr_groups++;

	}

	return nr_groups;

}

tools/lib/perf/include/internal/evlist.h

+0 −1
Original line number Diff line number Diff line
@@ -17,7 +17,6 @@ struct perf_mmap_param; 
struct perf_evlist {

	struct list_head	 entries;

	int			 nr_entries;

	int			 nr_groups;

	bool			 has_user_cpus;

	bool			 needs_map_propagation;

	/**

tools/lib/perf/include/perf/evlist.h

+1 −0
Original line number Diff line number Diff line
@@ -47,4 +47,5 @@ LIBPERF_API struct perf_mmap *perf_evlist__next_mmap(struct perf_evlist *evlist, 
	     (pos) = perf_evlist__next_mmap((evlist), (pos), overwrite))



LIBPERF_API void perf_evlist__set_leader(struct perf_evlist *evlist);

LIBPERF_API int perf_evlist__nr_groups(struct perf_evlist *evlist);

#endif /* __LIBPERF_EVLIST_H */

tools/perf/builtin-record.c

+1 −1
Original line number Diff line number Diff line
@@ -2474,7 +2474,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) 
		rec->tool.ordered_events = false;

	}



	if (!rec->evlist->core.nr_groups)

	if (evlist__nr_groups(rec->evlist) == 0)

		perf_header__clear_feat(&session->header, HEADER_GROUP_DESC);



	if (data->is_pipe) {

tools/perf/builtin-report.c

+1 −1
Original line number Diff line number Diff line
@@ -1481,7 +1481,7 @@ int cmd_report(int argc, const char **argv) 


	setup_forced_leader(&report, session->evlist);



	if (symbol_conf.group_sort_idx && !session->evlist->core.nr_groups) {

	if (symbol_conf.group_sort_idx && evlist__nr_groups(session->evlist) == 0) {

		parse_options_usage(NULL, options, "group-sort-idx", 0);

		ret = -EINVAL;

		goto error;