diff options
| author | Zijiang Huang <huangzjsmile@gmail.com> | 2026-05-06 21:09:19 +0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2026-05-28 21:05:08 -0700 |
| commit | 66366d291f666ddeda5f8c84f253e308de3e6b55 (patch) | |
| tree | e8fbdf8242d871119eb3417a7d9e960821f872da /mm | |
| parent | 9d5685286aa8c5ef70d8e1a34cef5daf518ae237 (diff) | |
| download | linux-next-history-66366d291f666ddeda5f8c84f253e308de3e6b55.tar.gz | |
mm/swap: add cond_resched() in swap_reclaim_full_clusters to prevent softlockup
We hit a real softlockup in an internal stress test environment. The
workload was LTP memory/swap stress on a large arm64 machine, with 320
CPUs, about 1TB memory and an 8.6GB swap device. The system was under
heavy load and the swap device had a large number of full clusters. The
softlockup was triggered during a stress test after about 3 days.
So, add periodic cond_resched() calls during large full_clusters
reclaim operations to prevent softlockup issues.
Detailed call trace as follow:
PID: 3817773 TASK: ffff0883bb28b780 CPU: 48 COMMAND: "kworker/48:7"
#0 [ffff800080183d10] __crash_kexec at ffffa4c1361e5de4
#1 [ffff800080183d90] panic at ffffa4c1360d5e9c
#2 [ffff800080183e20] watchdog_timer_fn at ffffa4c136231fa8
...
#16 [ffff8000c4ad3cb0] swap_cache_del_folio at ffffa4c1363e1614
#17 [ffff8000c4ad3ce0] __try_to_reclaim_swap at ffffa4c1363e4bfc
#18 [ffff8000c4ad3d40] swap_reclaim_full_clusters at ffffa4c1363e5474
#19 [ffff8000c4ad3da0] swap_reclaim_work at ffffa4c1363e550c
#20 [ffff8000c4ad3dc0] process_one_work at ffffa4c136102edc
#21 [ffff8000c4ad3e10] worker_thread at ffffa4c136103398
#22 [ffff8000c4ad3e70] kthread at ffffa4c13610d95c
Link: https://lore.kernel.org/20260506130919.2298807-1-kerayhuang@tencent.com
Fixes: 5168a68eb78f ("mm, swap: avoid over reclaim of full clusters")
Signed-off-by: Zijiang Huang <kerayhuang@tencent.com>
Reviewed-by: Kairui Song <kasong@tencent.com>
Reviewed-by: Hao Peng <flyingpeng@tencent.com>
Reviewed-by: albinwyang <albinwyang@tencent.com>
Reviewed-by: Baoquan He <baoquan.he@linux.dev>
Acked-by: Chris Li <chrisl@kernel.org>
Cc: Barry Song <baohua@kernel.org>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Youngjun Park <youngjun.park@lge.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/swapfile.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/mm/swapfile.c b/mm/swapfile.c index 9174f1eeffb09..74a1e324449dc 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1054,6 +1054,7 @@ static void swap_reclaim_full_clusters(struct swap_info_struct *si, bool force) swap_cluster_unlock(ci); if (to_scan <= 0) break; + cond_resched(); } } |