+ mm-damon-reclaim-make-enabled-checking-timer-simpler.patch added to mm-unstable branch

+ mm-damon-reclaim-make-enabled-checking-timer-simpler.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/damon/reclaim: make 'enabled' checking timer simpler
has been added to the -mm mm-unstable branch.  Its filename is
     mm-damon-reclaim-make-enabled-checking-timer-simpler.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-reclaim-make-enabled-checking-timer-simpler.patch

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

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------------------------------------------------------
From: SeongJae Park <sj@kernel.org>
Subject: mm/damon/reclaim: make 'enabled' checking timer simpler
Date: Mon, 6 Jun 2022 18:23:09 +0000

DAMON_RECLAIM's 'enabled' parameter store callback ('enabled_store()')
schedules the parameter check timer ('damon_reclaim_timer') if the
parameter is set as 'Y'.  Then, the timer schedules itself to check if
user has set the parameter as 'N'.  It's unnecessarily complex.

This commit makes it simpler by making the parameter store callback to
schedule the timer regardless of the parameter value and disabling the
timer's self scheduling.

Link: https://lkml.kernel.org/r/20220606182310.48781-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/damon/reclaim.c |    9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

--- a/mm/damon/reclaim.c~mm-damon-reclaim-make-enabled-checking-timer-simpler
+++ a/mm/damon/reclaim.c
@@ -353,7 +353,6 @@ static int damon_reclaim_turn(bool on)
 	return 0;
 }
 
-#define ENABLE_CHECK_INTERVAL_MS	1000
 static struct delayed_work damon_reclaim_timer;
 static void damon_reclaim_timer_fn(struct work_struct *work)
 {
@@ -367,10 +366,6 @@ static void damon_reclaim_timer_fn(struc
 		else
 			enabled = last_enabled;
 	}
-
-	if (enabled)
-		schedule_delayed_work(&damon_reclaim_timer,
-			msecs_to_jiffies(ENABLE_CHECK_INTERVAL_MS));
 }
 static DECLARE_DELAYED_WORK(damon_reclaim_timer, damon_reclaim_timer_fn);
 
@@ -382,9 +377,7 @@ static int enabled_store(const char *val
 	if (rc < 0)
 		return rc;
 
-	if (enabled)
-		schedule_delayed_work(&damon_reclaim_timer, 0);
-
+	schedule_delayed_work(&damon_reclaim_timer, 0);
 	return 0;
 }
 
_

Patches currently in -mm which might be from sj@kernel.org are

docs-admin-guide-damon-reclaim-remove-a-paragraph-that-been-obsolete-due-to-online-tuning-support.patch
mm-damon-dbgfssysfs-move-target_has_pid-from-dbgfs-to-damonh.patch
mm-damon-reclaim-deduplicate-commit_inputs-handling.patch
mm-damon-sysfs-deduplicate-inputs-applying.patch
mm-damon-reclaim-make-enabled-checking-timer-simpler.patch
mm-damon-reclaim-add-damon_reclaim_-prefix-to-enabled_store.patch