From 7013803444dd3bbbe28fd3360c084cec3057c554 Mon Sep 17 00:00:00 2001 From: Kaushlendra Kumar Date: Tue, 9 Dec 2025 10:15:52 +0530 Subject: [PATCH] tools/mm/page_owner_sort: fix timestamp comparison for stable sorting The ternary operator in compare_ts() returns 1 when timestamps are equal, causing unstable sorting behavior. Replace with explicit three-way comparison that returns 0 for equal timestamps, ensuring stable qsort ordering and consistent output. Link: https://lkml.kernel.org/r/20251209044552.3396468-1-kaushlendra.kumar@intel.com Fixes: 8f9c447e2e2b ("tools/vm/page_owner_sort.c: support sorting pid and time") Signed-off-by: Kaushlendra Kumar Cc: Chongxi Zhao Cc: Signed-off-by: Andrew Morton --- tools/mm/page_owner_sort.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/tools/mm/page_owner_sort.c b/tools/mm/page_owner_sort.c index 14c67e9e84c4..e6954909401c 100644 --- a/tools/mm/page_owner_sort.c +++ b/tools/mm/page_owner_sort.c @@ -181,7 +181,11 @@ static int compare_ts(const void *p1, const void *p2) { const struct block_list *l1 = p1, *l2 = p2; - return l1->ts_nsec < l2->ts_nsec ? -1 : 1; + if (l1->ts_nsec < l2->ts_nsec) + return -1; + if (l1->ts_nsec > l2->ts_nsec) + return 1; + return 0; } static int compare_cull_condition(const void *p1, const void *p2)