Skip to contentSkip to conversation

mm-damon-core-use-mult_frac-in-damon_feed_loop_next_input.patch removed from -mm tree

merged mm-stable Andrew Morton 1 participant 1 message Oct 13

lore
Share & tools
lore

Andrew Morton

author tree notice Applied
#0 lore raw

The quilt patch titled
Subject: mm/damon/core: use mult_frac() in damon_feed_loop_next_input()
has been removed from the -mm tree. Its filename was
mm-damon-core-use-mult_frac-in-damon_feed_loop_next_input.patch

This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: SJ Park <[email protected]>
Subject: mm/damon/core: use mult_frac() in damon_feed_loop_next_input()
Date: Thu, 17 Sep 2026 07:22:01 -0700

damon_feed_loop_next_input() does its best effort overflow protection. score_goal_diff is always smaller than goal (10,000). Hence the calculation can be replaced to use mult_frac() without concerning the overflow. Use mult_frac().

Link https://lore.kernel.org/[email protected] open here
Signed-off-by SJ Park <[email protected]>
Signed-off-by Andrew Morton <[email protected]>
Reviewed-by Asier Gutierrez <[email protected]>
Cc Brendan Higgins <[email protected]>
Cc David Gow <[email protected]>
Cc David Hildenbrand <[email protected]>
Cc Jonathan Corbet <[email protected]>
Cc Liam R. Howlett <[email protected]>
Cc Lorenzo Stoakes <[email protected]>
Cc Michal Hocko <[email protected]>
Cc Mike Rapoport <[email protected]>
Cc Randy Dunlap <[email protected]>
Cc Shuah Khan <[email protected]>
Cc Suren Baghdasaryan <[email protected]>
Cc Vlastimil Babka <[email protected]>

---

 mm/damon/core.c |    6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)
mm/damon/core.c renamed from mm/damon/core.c~mm-damon-core-use-mult_frac-in-damon_feed_loop_next_input +1 -5
@@ -2927,11 +2927,7 @@ static unsigned long damon_feed_loop_nex
 		return min_input;
 
 	score_goal_diff = abs_diff(score, goal);
-
-	if (last_input < ULONG_MAX / score_goal_diff)
-		compensation = last_input * score_goal_diff / goal;
-	else
-		compensation = last_input / goal * score_goal_diff;
+	compensation = mult_frac(last_input, score_goal_diff, goal);
 
 	if (over_achieving)
 		return max(last_input - compensation, min_input);

_

Patches currently in -mm which might be from [email protected] are

mm-damon-core-introduce-damos_quota_goal-complement.patch mm-damon-core-add-complement-argument-to-damos_new_quota_goal.patch mm-damon-sysfs-schemes-support-quota-goal-complement-flag.patch mm-damon-tests-core-kunit-test-quota_goal-complement-commit.patch selftests-damon-sysfssh-test-quota-goal-complement-flag-file.patch docs-mm-damon-design-document-damos-quota-goal-complement-flag.patch docs-admin-guide-mm-damon-usage-update-for-quota-goal-complement-file.patch docs-abi-damon-update-for-quota-goal-metric-complement-sysfs-file.patch