+ mm-damon-core-allow-esz-to-be-set-to-zero.patch added to mm-hotfixes-unstable branch

The patch titled
     Subject: mm/damon/core: allow esz to be set to zero
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     mm-damon-core-allow-esz-to-be-set-to-zero.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-core-allow-esz-to-be-set-to-zero.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Liew Rui Yan <redacted>
Subject: mm/damon/core: allow esz to be set to zero
Date: Tue, 8 Sep 2026 06:54:11 -0700

When the temporal quota goal tuner determines that the goal has been
achieved (score >= 10000), it sets esz_bp to zero so that the esz becomes
zero.  However, damos_set_effective_quota() clamps the esz to
min_region_sz when quota->ms is set.

This is a minor issue, the main problem is that it doesn't match the
description in the documentation, which state that if the goal has already
been [over-]achieved, the quota will be set to zero.

Fix this by set quota (esz) as minimum as possible.

Link: https://lore.kernel.org/20260908135413.97570-1-sj@kernel.org (local)
Fixes: 8bbde987c2b8 ("mm/damon/core: disallow time-quota setting zero esz")
Signed-off-by: SJ Park <sj@kernel.org>
Signed-off-by: Liew Rui Yan <redacted>
Reviewed-by: SJ Park <sj@kernel.org>
Cc: <redacted> # v7.1.x
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/damon/core.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

--- a/mm/damon/core.c~mm-damon-core-allow-esz-to-be-set-to-zero
+++ a/mm/damon/core.c

@@ -3091,6 +3091,7 @@ static void damos_set_effective_quota(st
 	struct damos_quota *quota = &s->quota;
 	unsigned long throughput;
 	unsigned long esz = ULONG_MAX;
+	unsigned long esz_time;
 
 	if (!quota->ms && list_empty(&quota->goals)) {
 		quota->esz = quota->sz;

@@ -3111,8 +3112,8 @@ static void damos_set_effective_quota(st
 					1000000, quota->total_charged_ns);
 		else
 			throughput = PAGE_SIZE * 1024;
-		esz = min(throughput * quota->ms, esz);
-		esz = max(ctx->min_region_sz, esz);
+		esz_time = max(throughput * quota->ms, ctx->min_region_sz);
+		esz = min(esz_time, esz);
 	}
 
 	if (quota->sz && quota->sz < esz)

_

Patches currently in -mm which might be from aethernet65535@gmail.com are

mm-damon-core-allow-esz-to-be-set-to-zero.patch
docs-mm-damon-design-accurate-semantics-of-nr_snapshots.patch
docs-mm-damon-design-difference-between-watermarks-and-nr_snapshots.patch
docs-mm-damon-design-fix-typo-of-max_nr_snapshots.patch