[PATCH v4 4/7] perf/util/session: Replace MAX_NR_CPUS with nr_cpus_online

[Kyle Meyer]

nr_cpus, the number of CPUs online during a record session bound by
MAX_NR_CPUS, can be used as a dynamic alternative for MAX_NR_CPUS in
perf_session__cpu_bitmap.

Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: Russ Anderson <russ.anderson@xxxxxxx>
Signed-off-by: Kyle Meyer <kyle.meyer@xxxxxxx>
---
 tools/perf/util/session.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 82e0438a9160..2f0d84a71ded 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -2291,6 +2291,7 @@ int perf_session__cpu_bitmap(struct perf_session *session,
 {
 	int i, err = -1;
 	struct perf_cpu_map *map;
+	int nr_cpus = min(session->header.env.nr_cpus_online, MAX_NR_CPUS);
 
 	for (i = 0; i < PERF_TYPE_MAX; ++i) {
 		struct evsel *evsel;
@@ -2315,7 +2316,7 @@ int perf_session__cpu_bitmap(struct perf_session *session,
 	for (i = 0; i < map->nr; i++) {
 		int cpu = map->map[i];
 
-		if (cpu >= MAX_NR_CPUS) {
+		if (cpu >= nr_cpus) {
 			pr_err("Requested CPU %d too large. "
 			       "Consider raising MAX_NR_CPUS\n", cpu);
 			goto out_delete_map;
-- 
2.12.3