The patch titled
Subject: mm/migrate: skip migrating folios under writeback with AS_WRITEBACK_INDETERMINATE mappings
has been added to the -mm mm-unstable branch. Its filename is
mm-migrate-skip-migrating-folios-under-writeback-with-as_writeback_indeterminate-mappings.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-migrate-skip-migrating-folios-under-writeback-with-as_writeback_indeterminate-mappings.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Joanne Koong <joannelkoong@xxxxxxxxx>
Subject: mm/migrate: skip migrating folios under writeback with AS_WRITEBACK_INDETERMINATE mappings
Date: Fri, 22 Nov 2024 15:23:58 -0800
For migrations called in MIGRATE_SYNC mode, skip migrating the folio if it
is under writeback and has the AS_WRITEBACK_INDETERMINATE flag set on its
mapping. If the AS_WRITEBACK_INDETERMINATE flag is set on the mapping,
the writeback may take an indeterminate amount of time to complete, and
waits may get stuck.
Link: https://lkml.kernel.org/r/20241122232359.429647-5-joannelkoong@xxxxxxxxx
Signed-off-by: Joanne Koong <joannelkoong@xxxxxxxxx>
Reviewed-by: Shakeel Butt <shakeel.butt@xxxxxxxxx>
Acked-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
Cc: Bernd Schubert <bernd.schubert@xxxxxxxxxxx>
Cc: Jingbo Xu <jefflexu@xxxxxxxxxxxxxxxxx>
Cc: Josef Bacik <josef@xxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/migrate.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
--- a/mm/migrate.c~mm-migrate-skip-migrating-folios-under-writeback-with-as_writeback_indeterminate-mappings
+++ a/mm/migrate.c
@@ -1254,7 +1254,10 @@ static int migrate_folio_unmap(new_folio
*/
switch (mode) {
case MIGRATE_SYNC:
- break;
+ if (!src->mapping ||
+ !mapping_writeback_indeterminate(src->mapping))
+ break;
+ fallthrough;
default:
rc = -EBUSY;
goto out;
_
Patches currently in -mm which might be from joannelkoong@xxxxxxxxx are
mm-add-as_writeback_indeterminate-mapping-flag.patch
mm-skip-reclaiming-folios-in-legacy-memcg-writeback-indeterminate-contexts.patch
fs-writeback-in-wait_sb_inodes-skip-wait-for-as_writeback_indeterminate-mappings.patch
mm-migrate-skip-migrating-folios-under-writeback-with-as_writeback_indeterminate-mappings.patch
fuse-remove-tmp-folio-for-writebacks-and-internal-rb-tree.patch
