libperf: Move 'leader' from tools/perf to perf_evsel::leader

Move evsel::leader to perf_evsel::leader, so we can move the group
interface to libperf.

Also add several evsel helpers to ease up the transition:

  struct evsel *evsel__leader(struct evsel *evsel);
  - get leader evsel

  bool evsel__has_leader(struct evsel *evsel, struct evsel *leader);
  - true if evsel has leader as leader

  bool evsel__is_leader(struct evsel *evsel);
  - true if evsel is itw own leader

  void evsel__set_leader(struct evsel *evsel, struct evsel *leader);
  - set leader for evsel

Committer notes:

Fix this when building with 'make BUILD_BPF_SKEL=1'

  tools/perf/util/bpf_counter.c

  -       if (evsel->leader->core.nr_members > 1) {
  +       if (evsel->core.leader->nr_members > 1) {

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Requested-by: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210706151704.73662-4-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 24 insertions, 5 deletions

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index cce16814dc2c..f61e5dd53f5d 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -241,7 +241,6 @@ void evsel__init(struct evsel *evsel,
 {
 	perf_evsel__init(&evsel->core, attr, idx);
 	evsel->tracking	   = !idx;
-	evsel->leader	   = evsel;
 	evsel->unit	   = "";
 	evsel->scale	   = 1.0;
 	evsel->max_events  = ULONG_MAX;
@@ -409,7 +408,7 @@ struct evsel *evsel__clone(struct evsel *orig)
 	evsel->cgrp = cgroup__get(orig->cgrp);
 	evsel->tp_format = orig->tp_format;
 	evsel->handler = orig->handler;
-	evsel->leader = orig->leader;
+	evsel->core.leader = orig->core.leader;
 
 	evsel->max_events = orig->max_events;
 	evsel->tool_event = orig->tool_event;
@@ -1074,7 +1073,7 @@ void __weak arch_evsel__set_sample_weight(struct evsel *evsel)
 void evsel__config(struct evsel *evsel, struct record_opts *opts,
 		   struct callchain_param *callchain)
 {
-	struct evsel *leader = evsel->leader;
+	struct evsel *leader = evsel__leader(evsel);
 	struct perf_event_attr *attr = &evsel->core.attr;
 	int track = evsel->tracking;
 	bool per_cpu = opts->target.default_per_cpu && !opts->target.per_thread;
@@ -1592,7 +1591,7 @@ static int evsel__match_other_cpu(struct evsel *evsel, struct evsel *other,
 
 static int evsel__hybrid_group_cpu(struct evsel *evsel, int cpu)
 {
-	struct evsel *leader = evsel->leader;
+	struct evsel *leader = evsel__leader(evsel);
 
 	if ((evsel__is_hybrid(evsel) && !evsel__is_hybrid(leader)) ||
 	    (!evsel__is_hybrid(evsel) && evsel__is_hybrid(leader))) {
@@ -1604,7 +1603,7 @@ static int evsel__hybrid_group_cpu(struct evsel *evsel, int cpu)
 
 static int get_group_fd(struct evsel *evsel, int cpu, int thread)
 {
-	struct evsel *leader = evsel->leader;
+	struct evsel *leader = evsel__leader(evsel);
 	int fd;
 
 	if (evsel__is_group_leader(evsel))
@@ -2850,3 +2849,23 @@ bool evsel__is_hybrid(struct evsel *evsel)
 {
 	return evsel->pmu_name && perf_pmu__is_hybrid(evsel->pmu_name);
 }
+
+struct evsel *evsel__leader(struct evsel *evsel)
+{
+	return container_of(evsel->core.leader, struct evsel, core);
+}
+
+bool evsel__has_leader(struct evsel *evsel, struct evsel *leader)
+{
+	return evsel->core.leader == &leader->core;
+}
+
+bool evsel__is_leader(struct evsel *evsel)
+{
+	return evsel__has_leader(evsel, evsel);
+}
+
+void evsel__set_leader(struct evsel *evsel, struct evsel *leader)
+{
+	evsel->core.leader = &leader->core;
+}