From aaa98b100ea8d779d3c4dae516dc5a267f51418b Mon Sep 17 00:00:00 2001 From: Imran Khan Date: Thu, 4 Jun 2026 21:42:45 +0800 Subject: [PATCH] mm/vmstat: avoid taking zone lock in /proc/buddyinfo reads frag_show_print() just reads zone->free_area[order].nr_free, so it can safely do this without needing the zone->lock. Pass nolock=true from frag_show(), so that walk_zones_in_node() can skip the zone->lock acquisition. Link: https://lore.kernel.org/20260604134245.1580287-1-imran.f.khan@oracle.com Signed-off-by: Imran Khan Reviewed-by: Joshua Hahn Acked-by: Vlastimil Babka (SUSE) Reviewed-by: Lorenzo Stoakes Acked-by: David Hildenbrand (Arm) Cc: Liam R. Howlett Cc: Michal Hocko Cc: Mike Rapoport Cc: Suren Baghdasaryan Signed-off-by: Andrew Morton --- mm/vmstat.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/vmstat.c b/mm/vmstat.c index f534972f517d..7b93fbf9af09 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1568,7 +1568,7 @@ static void frag_show_print(struct seq_file *m, pg_data_t *pgdat, static int frag_show(struct seq_file *m, void *arg) { pg_data_t *pgdat = (pg_data_t *)arg; - walk_zones_in_node(m, pgdat, true, false, frag_show_print); + walk_zones_in_node(m, pgdat, true, true, frag_show_print); return 0; }