The patch titled
Subject: mm/mglru: improve should_run_aging()
has been added to the -mm mm-unstable branch. Its filename is
mm-mglru-improve-should_run_aging.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-mglru-improve-should_run_aging.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: Kinsey Ho <kinseyho@xxxxxxxxxx>
Subject: mm/mglru: improve should_run_aging()
Date: Wed, 14 Feb 2024 06:05:35 +0000
scan_control *sc does not need to be passed into should_run_aging(), as it
provides only the reclaim priority. This can be moved to
get_nr_to_scan().
Refactor should_run_aging() and get_nr_to_scan() to improve code
readability. No functional changes.
Link: https://lkml.kernel.org/r/20240214060538.3524462-3-kinseyho@xxxxxxxxxx
Signed-off-by: Kinsey Ho <kinseyho@xxxxxxxxxx>
Cc: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
Cc: Donet Tom <donettom@xxxxxxxxxxxxxxxxxx>
Cc: Yu Zhao <yuzhao@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/vmscan.c | 25 +++++++++++--------------
1 file changed, 11 insertions(+), 14 deletions(-)
--- a/mm/vmscan.c~mm-mglru-improve-should_run_aging
+++ a/mm/vmscan.c
@@ -4585,14 +4585,13 @@ retry:
}
static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq,
- struct scan_control *sc, bool can_swap, unsigned long *nr_to_scan)
+ bool can_swap, unsigned long *nr_to_scan)
{
int gen, type, zone;
unsigned long old = 0;
unsigned long young = 0;
unsigned long total = 0;
struct lru_gen_folio *lrugen = &lruvec->lrugen;
- struct mem_cgroup *memcg = lruvec_memcg(lruvec);
DEFINE_MIN_SEQ(lruvec);
/* whether this lruvec is completely out of cold folios */
@@ -4620,13 +4619,7 @@ static bool should_run_aging(struct lruv
}
}
- /* try to scrape all its memory if this memcg was deleted */
- if (!mem_cgroup_online(memcg)) {
- *nr_to_scan = total;
- return false;
- }
-
- *nr_to_scan = total >> sc->priority;
+ *nr_to_scan = total;
/*
* The aging tries to be lazy to reduce the overhead, while the eviction
@@ -4658,6 +4651,7 @@ static bool should_run_aging(struct lruv
*/
static long get_nr_to_scan(struct lruvec *lruvec, struct scan_control *sc, bool can_swap)
{
+ bool success;
unsigned long nr_to_scan;
struct mem_cgroup *memcg = lruvec_memcg(lruvec);
DEFINE_MAX_SEQ(lruvec);
@@ -4665,14 +4659,17 @@ static long get_nr_to_scan(struct lruvec
if (mem_cgroup_below_min(sc->target_mem_cgroup, memcg))
return -1;
- if (!should_run_aging(lruvec, max_seq, sc, can_swap, &nr_to_scan))
- return nr_to_scan;
+ success = should_run_aging(lruvec, max_seq, can_swap, &nr_to_scan);
- /* skip the aging path at the default priority */
- if (sc->priority == DEF_PRIORITY)
+ /* try to scrape all its memory if this memcg was deleted */
+ if (nr_to_scan && !mem_cgroup_online(memcg))
return nr_to_scan;
- /* skip this lruvec as it's low on cold folios */
+ /* try to get away with not aging at the default priority */
+ if (!success || sc->priority == DEF_PRIORITY)
+ return nr_to_scan >> sc->priority;
+
+ /* stop scanning this lruvec as it's low on cold folios */
return try_to_inc_max_seq(lruvec, max_seq, can_swap, false) ? -1 : 0;
}
_
Patches currently in -mm which might be from kinseyho@xxxxxxxxxx are
mm-mglru-drop-unused-parameter.patch
mm-mglru-improve-should_run_aging.patch
mm-mglru-improve-reset_mm_stats.patch
mm-mglru-improve-struct-lru_gen_mm_walk.patch
mm-mglru-improve-swappiness-handling.patch
