perf sched timehist: Fix use of CPU list with summary option

Do not update thread stats or show idle summary unless CPU is in the
list of interest.

Fixes: c30d630d ("perf sched timehist: Add support for filtering on CPU")
Signed-off-by: David Ahern <dsahern@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Link: http://lore.kernel.org/lkml/20200817170943.1486-1-dsahern@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-sched.c

@@ -2584,6 +2584,7 @@ static int timehist_sched_change_event(struct perf_tool *tool,
 	}
 
 	if (!sched->idle_hist || thread->tid == 0) {
+		if (!cpu_list || test_bit(sample->cpu, cpu_bitmap))
 			timehist_update_runtime_stats(tr, t, tprev);
 
 		if (sched->idle_hist) {
@@ -2857,6 +2858,9 @@ static void timehist_print_summary(struct perf_sched *sched,
 
 	printf("\nIdle stats:\n");
 	for (i = 0; i < idle_max_cpu; ++i) {
+		if (cpu_list && !test_bit(i, cpu_bitmap))
+			continue;
+
 		t = idle_threads[i];
 		if (!t)
 			continue;