libperf: Propagate maps only if necessary

The current code propagate evsel's cpu map settings to evlist when it's
added to an evlist.  But the evlist->all_cpus and each evsel's cpus will
be updated in perf_evlist__set_maps() later.  No need to do it before
evlist's cpus are set actually.

In fact it discards this intermediate all_cpus maps at the beginning
of perf_evlist__set_maps().  Let's not do this.  It's only needed when
an evsel is added after the evlist cpu/thread maps are set.

Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20221003204647.1481128-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/lib/perf/evlist.c b/tools/lib/perf/evlist.c
index 19eaea9..61b637f 100644 (file)
--- a/tools/lib/perf/evlist.c
+++ b/tools/lib/perf/evlist.c
@@ -67,9 +67,7 @@ static void perf_evlist__propagate_maps(struct perf_evlist *evlist)
 {
        struct perf_evsel *evsel;
 
-       /* Recomputing all_cpus, so start with a blank slate. */
-       perf_cpu_map__put(evlist->all_cpus);
-       evlist->all_cpus = NULL;
+       evlist->needs_map_propagation = true;
 
        perf_evlist__for_each_evsel(evlist, evsel)
                __perf_evlist__propagate_maps(evlist, evsel);
@@ -81,7 +79,9 @@ void perf_evlist__add(struct perf_evlist *evlist,
        evsel->idx = evlist->nr_entries;
        list_add_tail(&evsel->node, &evlist->entries);
        evlist->nr_entries += 1;
-       __perf_evlist__propagate_maps(evlist, evsel);
+
+       if (evlist->needs_map_propagation)
+               __perf_evlist__propagate_maps(evlist, evsel);
 }
 
 void perf_evlist__remove(struct perf_evlist *evlist,
@@ -177,9 +177,6 @@ void perf_evlist__set_maps(struct perf_evlist *evlist,
                evlist->threads = perf_thread_map__get(threads);
        }
 
-       if (!evlist->all_cpus && cpus)
-               evlist->all_cpus = perf_cpu_map__get(cpus);
-
        perf_evlist__propagate_maps(evlist);
 }
 

diff --git a/tools/lib/perf/include/internal/evlist.h b/tools/lib/perf/include/internal/evlist.h
index 6f89aec..850f070 100644 (file)
--- a/tools/lib/perf/include/internal/evlist.h
+++ b/tools/lib/perf/include/internal/evlist.h
@@ -19,6 +19,7 @@ struct perf_evlist {
        int                      nr_entries;
        int                      nr_groups;
        bool                     has_user_cpus;
+       bool                     needs_map_propagation;
        /**
         * The cpus passed from the command line or all online CPUs by
         * default.