From 242a764abe149f297273be18fdb66cfeaf27dec2 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Fri, 6 Mar 2026 07:29:07 -0800 Subject: [PATCH] mm/damon/core: add damon_nr_regions() debug_sanity check damon_target->nr_regions is introduced to get the number quickly without having to iterate regions always. Add a sanity check for that under CONFIG_DAMON_DEBUG_SANITY. Link: https://lkml.kernel.org/r/20260306152914.86303-5-sj@kernel.org Signed-off-by: SeongJae Park Cc: Brendan Higgins Cc: David Gow Cc: Shuah Khan Signed-off-by: Andrew Morton --- mm/damon/core.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/mm/damon/core.c b/mm/damon/core.c index c499a02ac44e..16bedde920f0 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -545,8 +545,27 @@ void damon_destroy_target(struct damon_target *t, struct damon_ctx *ctx) damon_free_target(t); } +#ifdef CONFIG_DAMON_DEBUG_SANITY +static void damon_verify_nr_regions(struct damon_target *t) +{ + struct damon_region *r; + unsigned int count = 0; + + damon_for_each_region(r, t) + count++; + WARN_ONCE(count != t->nr_regions, "t->nr_regions (%u) != count (%u)\n", + t->nr_regions, count); +} +#else +static void damon_verify_nr_regions(struct damon_target *t) +{ +} +#endif + unsigned int damon_nr_regions(struct damon_target *t) { + damon_verify_nr_regions(t); + return t->nr_regions; }