mm: vmscan.c: fix OOM on swap stress test

BugLink: https://bugs.launchpad.net/bugs/2097393

commit 0885ef4705607936fc36a38fd74356e1c465b023 upstream.

I found a regression on mm-unstable during my swap stress test, using
tmpfs to compile linux.  The test OOM very soon after the make spawns many
cc processes.

It bisects down to this change: 33dfe9204f29b415bbc0abb1a50642d1ba94f5e9
(mm/gup: clear the LRU flag of a page before adding to LRU batch)

Yu Zhao propose the fix: "I think this is one of the potential side
effects -- Huge mentioned earlier about isolate_lru_folios():"

I test that with it the swap stress test no longer OOM.

Link: https://lore.kernel.org/r/CAOUHufYi9h0kz5uW3LHHS3ZrVwEq-kKp8S6N-MZUmErNAXoXmw@mail.gmail.com/
Link: https://lkml.kernel.org/r/20240905-lru-flag-v2-1-8a2d9046c594@kernel.org
Fixes: 33dfe9204f29 ("mm/gup: clear the LRU flag of a page before adding to LRU batch")
Signed-off-by: Chris Li <chrisl@kernel.org>
Suggested-by: Yu Zhao <yuzhao@google.com>
Suggested-by: Hugh Dickins <hughd@google.com>
Closes: https://lore.kernel.org/all/CAF8kJuNP5iTj2p07QgHSGOJsiUfYpJ2f4R1Q5-3BN9JiD9W_KA@mail.gmail.com/
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Manuel Diewald <manuel.diewald@canonical.com>
Signed-off-by: Koichiro Den <koichiro.den@canonical.com>

This commit is contained in:

Chris Li

2024-09-05 01:08:17 -07:00

committed by

Mehmet Basaran

parent 40b35fe31f

commit 74baf1b4bd

1 changed files with 1 additions and 1 deletions

									
										mm/vmscan.c
									
		+1
		-1
	
												View File
												
				@@ -4281,7 +4281,7 @@ static bool sort_folio(struct lruvec *lruvec, struct folio *folio, struct scan_c

					}

					/* ineligible */

					if (zone > sc->reclaim_idx) {

					if (!folio_test_lru(folio) || zone > sc->reclaim_idx) {

						gen = folio_inc_gen(lruvec, folio, false);

						list_move_tail(&folio->lru, &lrugen->folios[gen][type][zone]);

						return true;