From: sashiko-bot@kernel.org
To: "SJ Park" <sj@kernel.org>
Cc: damon@lists.linux.dev
Subject: Re: [PATCH 3/3] mm/damon/core: move static variable rotation to damon_ctx
Date: Sun, 25 Oct 2026 16:51:44 +0000 [thread overview]
Message-ID: <sashiko-outbox-184282@kernel.org> (raw)
In-Reply-To: <20261025164808.152048-4-sj@kernel.org>
> damon_split_some_reigons() uses a static variable, rotation, to remember
> how many times it was called. It is again used to determine fair
> selection of regions to split. Since it is a static variable, it can be
> indeterministic and therefore less fair.
>
> The user impact is not critical. No crash, no leak. DAMON's
> best-effort and indeterministic monitoring accuracy could be slightly
> more indeterministic when multiple kdamonds are used in parallel.
>
> Fix the problem by moving the static variable into the damon_ctx struct.
>
> Fixes: 1a582e6e0174 ("mm/damon/core: split a fraction of regions when nr_regions exceeds max/2")
> Cc: <stable@vger.kernel.org> # 7.3.x
> Closes: https://sashiko.dev/#/bug/linux-eebfcdde-2881-48ef-8df1-e2019d2a47f2
> Signed-off-by: SJ Park <sj@kernel.org>
Sashiko has reviewed this patch and found no issues.
--
Sashiko AI review · https://sashiko.dev/#/patchset/20261025164808.152048-1-sj@kernel.org?part=3
prev parent reply other threads:[~2026-10-25 16:51 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-25 16:48 [PATCH 0/3] mm/damon: fix three race bugs in sysfs and core SJ Park
2026-10-25 16:48 ` [PATCH 1/3] mm/damon/sysfs-schemes: hold damon_sysfs_lock in target_metric_store() SJ Park
2026-10-25 16:52 ` sashiko-bot
2026-10-25 16:48 ` [PATCH 2/3] mm/damon/core: move static variable last_nr_regions to damon_ctx SJ Park
2026-10-25 16:53 ` sashiko-bot
2026-10-25 16:48 ` [PATCH 3/3] mm/damon/core: move static variable rotation " SJ Park
2026-10-25 16:51 ` sashiko-bot [this message]
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