At time of damon_reset_aggregated(), aggregation of the interval should be completed, and hence nr_accesses and nr_accesses_bp should match. I found a few bugs caused it to be broken in the past, from online parameters update and complicated nr_accesses handling changes. Add a sanity check for that under CONFIG_DAMON_DEBUG_SANITY. Signed-off-by: SeongJae Park --- mm/damon/core.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/mm/damon/core.c b/mm/damon/core.c index 16f7994903d6d..4efe732e76c69 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -1681,6 +1681,28 @@ static void damon_warn_fix_nr_accesses_corruption(struct damon_region *r) r->nr_accesses_bp = r->nr_accesses * 10000; } +#ifdef CONFIG_DAMON_DEBUG_SANITY +static void damon_verify_reset_aggregated(struct damon_region *r, + struct damon_ctx *c) +{ + if (r->nr_accesses_bp == r->last_nr_accesses * 10000) + return; + pr_err("reset time invalid region found!\n"); + pr_err("nr_accesses_bp %u last_nr_acceses %u\n", + r->nr_accesses_bp, r->last_nr_accesses); + pr_err("passed_sis %lu next_aggregation_sis %lu\n", + c->passed_sample_intervals, + c->next_aggregation_sis); + WARN_ONCE(); +} +#else +static void damon_verify_reset_aggregated(struct damon_region *r, + struct damon_ctx *c) +{ +} +#endif + + /* * Reset the aggregated monitoring results ('nr_accesses' of each region). */ @@ -1697,6 +1719,7 @@ static void kdamond_reset_aggregated(struct damon_ctx *c) damon_warn_fix_nr_accesses_corruption(r); r->last_nr_accesses = r->nr_accesses; r->nr_accesses = 0; + damon_verify_reset_aggregated(r, c); } ti++; } -- 2.47.3