perf cpumap: Compute mask size in constant time

perf_cpu_map__max() computes the cpumap's maximum value, no need to
iterate over all values.

Signed-off-by: Ian Rogers <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Alexey Bayduraev <[email protected]>
Cc: Athira Jajeev <[email protected]>
Cc: Colin Ian King <[email protected]>
Cc: Dave Marchevsky <[email protected]>
Cc: German Gomez <[email protected]>
Cc: Gustavo A. R. Silva <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Kees Kook <[email protected]>
Cc: Leo Yan <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Riccardo Mancini <[email protected]>
Cc: Song Liu <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

1 files changed, 1 insertions, 12 deletions

diff --git a/tools/perf/util/synthetic-events.c b/tools/perf/util/synthetic-events.c
index b3e03a4c6652..3ae7c0f54157 100644
--- a/tools/perf/util/synthetic-events.c
+++ b/tools/perf/util/synthetic-events.c
@@ -1214,18 +1214,7 @@ static size_t cpus_size(const struct perf_cpu_map *map)
 
 static size_t mask_size(const struct perf_cpu_map *map, int *max)
 {
-	int i;
-
-	*max = 0;
-
-	for (i = 0; i < perf_cpu_map__nr(map); i++) {
-		/* bit position of the cpu is + 1 */
-		int bit = perf_cpu_map__cpu(map, i).cpu + 1;
-
-		if (bit > *max)
-			*max = bit;
-	}
-
+	*max = perf_cpu_map__max(map).cpu;
 	return sizeof(struct perf_record_record_cpu_map) + BITS_TO_LONGS(*max) * sizeof(long);
 }