tools/sched_ext: scx_nest: zero-initialize stats counter array

[PATCH] tools/sched_ext: scx_nest: zero-initialize stats counter array

David Carlier posted 1 patch 1 month, 2 weeks ago

Download mbox

tools/sched_ext/scx_flatcg.c | 1 +
1 file changed, 1 insertion(+)

Expand all Fold all

[PATCH] tools/sched_ext: scx_nest: zero-initialize stats counter array

Posted by David Carlier 1 month, 2 weeks ago

The local cnts array in read_stats() is not initialized before being
accumulated into per-CPU stats, which may lead to reading garbage
values. Zero it out with memset alongside the existing stats array
initialization.

Signed-off-by: David Carlier <devnexen@gmail.com>
---
 tools/sched_ext/scx_flatcg.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/sched_ext/scx_flatcg.c b/tools/sched_ext/scx_flatcg.c
index cd85eb401179..bea76d060201 100644
--- a/tools/sched_ext/scx_flatcg.c
+++ b/tools/sched_ext/scx_flatcg.c
@@ -106,6 +106,7 @@ static void fcg_read_stats(struct scx_flatcg *skel, __u64 *stats)
 	__u32 idx;
 
 	memset(stats, 0, sizeof(stats[0]) * FCG_NR_STATS);
+	memset(cnts, 0, sizeof(cnts));
 
 	for (idx = 0; idx < FCG_NR_STATS; idx++) {
 		int ret, cpu;
-- 
2.51.0

Re: [PATCH] tools/sched_ext: scx_nest: zero-initialize stats counter array

Posted by Tejun Heo 1 month, 2 weeks ago

Applied to sched_ext/for-7.0-fixes with the subject fixed
(s/scx_nest/scx_flatcg/).

Thanks.

--
tejun