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In this situation, damos_adjust_quota() still calculates quota->min_score for it. However, this min_score will not be used in this window, because in damon_do_apply_schemes(), damos_quota_is_full() will always returns true, preventing the scheme from being applied to any region. Therefore, add a short circuit for temporal-goal algorithm schemes to early return from damos_adjust_quota() before calculating min_score. Signed-off-by: Liew Rui Yan --- I tested with virtme-ng + perf on a Proactive Memory Reclaim workload; within measurement noise (~3%), no measurable difference was observed. The purpose of this patch is to reduce unnecessary operations (calculating min_score). But, I'd like to know if this patch needs to demonstrate that it provides better performance before it's merged. --- mm/damon/core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/damon/core.c b/mm/damon/core.c index ce8c6f99106e..fdcea989f0e0 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -3320,6 +3320,8 @@ static void damos_adjust_quota(struct damon_ctx *c, struct damos *s) if (!c->ops.get_scheme_score) return; + if (quota->esz == 0) + return; /* Fill up the score histogram */ memset(c->regions_score_histogram, 0, -- 2.55.0