[tip: perf/core] perf session: Replace MAX_NR_CPUS with perf_env::nr_cpus_online

[tip-bot2 for Kyle Meyer]

The following commit has been merged into the perf/core branch of tip:

Commit-ID:     7df4e36a4785618f0c63f3dc2bacb164780ab0f6
Gitweb:        https://git.kernel.org/tip/7df4e36a4785618f0c63f3dc2bacb164780ab0f6
Author:        Kyle Meyer <meyerk@xxxxxxx>
AuthorDate:    Tue, 27 Aug 2019 16:43:49 -05:00
Committer:     Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitterDate: Thu, 29 Aug 2019 17:38:32 -03:00

perf session: Replace MAX_NR_CPUS with perf_env::nr_cpus_online

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.

Signed-off-by: Kyle Meyer <kyle.meyer@xxxxxxx>
Reviewed-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Russ Anderson <russ.anderson@xxxxxxx>
Link: http://lore.kernel.org/lkml/20190827214352.94272-5-meyerk@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 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 7350b0d..13486bc 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -2292,6 +2292,7 @@ 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;
@@ -2316,7 +2317,7 @@ 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;