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: Ian 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: Arnaldo Carvalho de Melo <acme@redhat.com>

3 files changed, 17 insertions, 18 deletions

diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c
index ae9223f27cfb..8beb46066034 100644
--- a/tools/perf/tests/bpf.c
+++ b/tools/perf/tests/bpf.c
@@ -153,7 +153,6 @@ static int do_test(struct bpf_object *obj, int (*func)(void),
 	}
 
 	evlist__splice_list_tail(evlist, &parse_state.list);
-	evlist->core.nr_groups = parse_state.nr_groups;
 
 	evlist__config(evlist, &opts, NULL);
 
diff --git a/tools/perf/tests/parse-events.c b/tools/perf/tests/parse-events.c
index 71a5cb343311..ffa6f0a90741 100644
--- a/tools/perf/tests/parse-events.c
+++ b/tools/perf/tests/parse-events.c
@@ -53,7 +53,7 @@ static int test__checkevent_tracepoint(struct evlist *evlist)
 	struct evsel *evsel = evlist__first(evlist);
 
 	TEST_ASSERT_VAL("wrong number of entries", 1 == evlist->core.nr_entries);
-	TEST_ASSERT_VAL("wrong number of groups", 0 == evlist->core.nr_groups);
+	TEST_ASSERT_VAL("wrong number of groups", 0 == evlist__nr_groups(evlist));
 	TEST_ASSERT_VAL("wrong type", PERF_TYPE_TRACEPOINT == evsel->core.attr.type);
 	TEST_ASSERT_VAL("wrong sample_type",
 		PERF_TP_SAMPLE_TYPE == evsel->core.attr.sample_type);
@@ -66,7 +66,7 @@ static int test__checkevent_tracepoint_multi(struct evlist *evlist)
 	struct evsel *evsel;
 
 	TEST_ASSERT_VAL("wrong number of entries", evlist->core.nr_entries > 1);
-	TEST_ASSERT_VAL("wrong number of groups", 0 == evlist->core.nr_groups);
+	TEST_ASSERT_VAL("wrong number of groups", 0 == evlist__nr_groups(evlist));
 
 	evlist__for_each_entry(evlist, evsel) {
 		TEST_ASSERT_VAL("wrong type",
@@ -677,7 +677,7 @@ static int test__group1(struct evlist *evlist)
 	struct evsel *evsel, *leader;
 
 	TEST_ASSERT_VAL("wrong number of entries", 2 == evlist->core.nr_entries);
-	TEST_ASSERT_VAL("wrong number of groups", 1 == evlist->core.nr_groups);
+	TEST_ASSERT_VAL("wrong number of groups", 1 == evlist__nr_groups(evlist));
 
 	/* instructions:k */
 	evsel = leader = evlist__first(evlist);
@@ -719,7 +719,7 @@ static int test__group2(struct evlist *evlist)
 	struct evsel *evsel, *leader;
 
 	TEST_ASSERT_VAL("wrong number of entries", 3 == evlist->core.nr_entries);
-	TEST_ASSERT_VAL("wrong number of groups", 1 == evlist->core.nr_groups);
+	TEST_ASSERT_VAL("wrong number of groups", 1 == evlist__nr_groups(evlist));
 
 	/* faults + :ku modifier */
 	evsel = leader = evlist__first(evlist);
@@ -775,7 +775,7 @@ static int test__group3(struct evlist *evlist __maybe_unused)
 	struct evsel *evsel, *leader;
 
 	TEST_ASSERT_VAL("wrong number of entries", 5 == evlist->core.nr_entries);
-	TEST_ASSERT_VAL("wrong number of groups", 2 == evlist->core.nr_groups);
+	TEST_ASSERT_VAL("wrong number of groups", 2 == evlist__nr_groups(evlist));
 
 	/* group1 syscalls:sys_enter_openat:H */
 	evsel = leader = evlist__first(evlist);
@@ -868,7 +868,7 @@ static int test__group4(struct evlist *evlist __maybe_unused)
 	struct evsel *evsel, *leader;
 
 	TEST_ASSERT_VAL("wrong number of entries", 2 == evlist->core.nr_entries);
-	TEST_ASSERT_VAL("wrong number of groups", 1 == evlist->core.nr_groups);
+	TEST_ASSERT_VAL("wrong number of groups", 1 == evlist__nr_groups(evlist));
 
 	/* cycles:u + p */
 	evsel = leader = evlist__first(evlist);
@@ -912,7 +912,7 @@ static int test__group5(struct evlist *evlist __maybe_unused)
 	struct evsel *evsel, *leader;
 
 	TEST_ASSERT_VAL("wrong number of entries", 5 == evlist->core.nr_entries);
-	TEST_ASSERT_VAL("wrong number of groups", 2 == evlist->core.nr_groups);
+	TEST_ASSERT_VAL("wrong number of groups", 2 == evlist__nr_groups(evlist));
 
 	/* cycles + G */
 	evsel = leader = evlist__first(evlist);
@@ -998,7 +998,7 @@ static int test__group_gh1(struct evlist *evlist)
 	struct evsel *evsel, *leader;
 
 	TEST_ASSERT_VAL("wrong number of entries", 2 == evlist->core.nr_entries);
-	TEST_ASSERT_VAL("wrong number of groups", 1 == evlist->core.nr_groups);
+	TEST_ASSERT_VAL("wrong number of groups", 1 == evlist__nr_groups(evlist));
 
 	/* cycles + :H group modifier */
 	evsel = leader = evlist__first(evlist);
@@ -1038,7 +1038,7 @@ static int test__group_gh2(struct evlist *evlist)
 	struct evsel *evsel, *leader;
 
 	TEST_ASSERT_VAL("wrong number of entries", 2 == evlist->core.nr_entries);
-	TEST_ASSERT_VAL("wrong number of groups", 1 == evlist->core.nr_groups);
+	TEST_ASSERT_VAL("wrong number of groups", 1 == evlist__nr_groups(evlist));
 
 	/* cycles + :G group modifier */
 	evsel = leader = evlist__first(evlist);
@@ -1078,7 +1078,7 @@ static int test__group_gh3(struct evlist *evlist)
 	struct evsel *evsel, *leader;
 
 	TEST_ASSERT_VAL("wrong number of entries", 2 == evlist->core.nr_entries);
-	TEST_ASSERT_VAL("wrong number of groups", 1 == evlist->core.nr_groups);
+	TEST_ASSERT_VAL("wrong number of groups", 1 == evlist__nr_groups(evlist));
 
 	/* cycles:G + :u group modifier */
 	evsel = leader = evlist__first(evlist);
@@ -1118,7 +1118,7 @@ static int test__group_gh4(struct evlist *evlist)
 	struct evsel *evsel, *leader;
 
 	TEST_ASSERT_VAL("wrong number of entries", 2 == evlist->core.nr_entries);
-	TEST_ASSERT_VAL("wrong number of groups", 1 == evlist->core.nr_groups);
+	TEST_ASSERT_VAL("wrong number of groups", 1 == evlist__nr_groups(evlist));
 
 	/* cycles:G + :uG group modifier */
 	evsel = leader = evlist__first(evlist);
diff --git a/tools/perf/tests/pfm.c b/tools/perf/tests/pfm.c
index 71b76deb1f92..2e38dfa34b6c 100644
--- a/tools/perf/tests/pfm.c
+++ b/tools/perf/tests/pfm.c
@@ -76,7 +76,7 @@ static int test__pfm_events(struct test_suite *test __maybe_unused,
 				count_pfm_events(&evlist->core),
 				table[i].nr_events);
 		TEST_ASSERT_EQUAL(table[i].events,
-				evlist->core.nr_groups,
+				evlist__nr_groups(evlist),
 				0);
 
 		evlist__delete(evlist);
@@ -103,22 +103,22 @@ static int test__pfm_group(struct test_suite *test __maybe_unused,
 		{
 			.events = "{instructions}",
 			.nr_events = 1,
-			.nr_groups = 1,
+			.nr_groups = 0,
 		},
 		{
 			.events = "{instructions},{}",
 			.nr_events = 1,
-			.nr_groups = 1,
+			.nr_groups = 0,
 		},
 		{
 			.events = "{},{instructions}",
 			.nr_events = 1,
-			.nr_groups = 1,
+			.nr_groups = 0,
 		},
 		{
 			.events = "{instructions},{instructions}",
 			.nr_events = 2,
-			.nr_groups = 2,
+			.nr_groups = 0,
 		},
 		{
 			.events = "{instructions,cycles},{instructions,cycles}",
@@ -161,7 +161,7 @@ static int test__pfm_group(struct test_suite *test __maybe_unused,
 				count_pfm_events(&evlist->core),
 				table[i].nr_events);
 		TEST_ASSERT_EQUAL(table[i].events,
-				evlist->core.nr_groups,
+				evlist__nr_groups(evlist),
 				table[i].nr_groups);
 
 		evlist__delete(evlist);