perf evsel: Separate missing feature disabling from evsel__open_cpu

This is a preparatory patch for the patches in the workqueue series with
the goal to separate in evlist__open_cpu() the actual opening, which
could be performed in parallel, from the existing fallback mechanisms,
which should be handled sequentially.

This patch separates the disabling of missing features from
evlist__open_cpu() into a new function evsel__disable_missing_features(().
Signed-off-by: NRiccardo Mancini <rickyman7@gmail.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/48138bd2932646dde315505da733c2ca635ad2ee.1629490974.git.rickyman7@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/evsel.c

@@ -1794,33 +1794,8 @@ static int __evsel__prepare_open(struct evsel *evsel, struct perf_cpu_map *cpus,
 	return 0;
 }
 
-static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,
-		struct perf_thread_map *threads,
-		int start_cpu, int end_cpu)
+static void evsel__disable_missing_features(struct evsel *evsel)
 {
-	int cpu, thread, nthreads;
-	int pid = -1, err, old_errno;
-	enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
-
-	err = __evsel__prepare_open(evsel, cpus, threads);
-	if (err)
-		return err;
-
-	if (cpus == NULL)
-		cpus = empty_cpu_map;
-
-	if (threads == NULL)
-		threads = empty_thread_map;
-
-	if (evsel->core.system_wide)
-		nthreads = 1;
-	else
-		nthreads = threads->nr;
-
-	if (evsel->cgrp)
-		pid = evsel->cgrp->fd;
-
-fallback_missing_features:
 	if (perf_missing_features.weight_struct) {
 		evsel__set_sample_bit(evsel, WEIGHT);
 		evsel__reset_sample_bit(evsel, WEIGHT_STRUCT);
@@ -1850,6 +1825,36 @@ static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,
 		evsel->core.attr.branch_sample_type &= ~PERF_SAMPLE_BRANCH_HW_INDEX;
 	if (perf_missing_features.sample_id_all)
 		evsel->core.attr.sample_id_all = 0;
+}
+
+static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,
+		struct perf_thread_map *threads,
+		int start_cpu, int end_cpu)
+{
+	int cpu, thread, nthreads;
+	int pid = -1, err, old_errno;
+	enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
+
+	err = __evsel__prepare_open(evsel, cpus, threads);
+	if (err)
+		return err;
+
+	if (cpus == NULL)
+		cpus = empty_cpu_map;
+
+	if (threads == NULL)
+		threads = empty_thread_map;
+
+	if (evsel->core.system_wide)
+		nthreads = 1;
+	else
+		nthreads = threads->nr;
+
+	if (evsel->cgrp)
+		pid = evsel->cgrp->fd;
+
+fallback_missing_features:
+	evsel__disable_missing_features(evsel);
 
 	display_attr(&evsel->core.attr);