Hi all,
Today's linux-next merge of the mm tree got a conflict in:
mm/vmscan.c
between commit:
15077be8badc ("vmscan: Add check_move_unevictable_folios()")
from the folio tree and commits:
cca700a8e695 ("mm: lru: use lruvec lock to serialize memcg changes")
from the mm tree.
I fixed it up (see below) and can carry the fix as necessary. This
is now fixed as far as linux-next is concerned, but any non trivial
conflicts should be mentioned to your upstream maintainer when your tree
is submitted for merging. You may also want to consider cooperating
with the maintainer of the conflicting tree to minimise any particularly
complex conflicts.
--
Cheers,
Stephen Rothwell
diff --cc mm/vmscan.c
index 04f8671caad9,60335f974803..000000000000
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@@ -4823,18 -4856,22 +4873,17 @@@ void check_move_unevictable_folios(stru
int pgrescued = 0;
int i;
- for (i = 0; i < pvec->nr; i++) {
- struct page *page = pvec->pages[i];
- struct folio *folio = page_folio(page);
- int nr_pages;
-
- if (PageTransTail(page))
- continue;
+ for (i = 0; i < fbatch->nr; i++) {
+ struct folio *folio = fbatch->folios[i];
+ int nr_pages = folio_nr_pages(folio);
- nr_pages = folio_nr_pages(folio);
pgscanned += nr_pages;
- /* block memcg migration while the folio moves between lrus */
- if (!folio_test_clear_lru(folio))
+ lruvec = folio_lruvec_relock_irq(folio, lruvec);
+ if (!folio_test_lru(folio) || !folio_test_unevictable(folio))
continue;
- lruvec = folio_lruvec_relock_irq(folio, lruvec);
- if (folio_evictable(folio) && folio_test_unevictable(folio)) {
+ if (folio_evictable(folio)) {
lruvec_del_folio(lruvec, folio);
folio_clear_unevictable(folio);
lruvec_add_folio(lruvec, folio);
On Wed, Jun 22, 2022 at 1:38 PM Stephen Rothwell <[email protected]> wrote:
>
> Hi all,
>
> Today's linux-next merge of the mm tree got a conflict in:
>
> mm/vmscan.c
>
> between commit:
>
> 15077be8badc ("vmscan: Add check_move_unevictable_folios()")
Sorry for the conflicts, I didn't see this change in the mm-unstable branch
yesterday. Based on this commit, I have reworked the following commit
(see attachment, mainly changes are about check_move_unevictable_folios()).
Andrew can pick it up if he wants to replace the original patch with
the new one.
>
> from the folio tree and commits:
>
> cca700a8e695 ("mm: lru: use lruvec lock to serialize memcg changes")
>
> from the mm tree.
>
> I fixed it up (see below) and can carry the fix as necessary. This
> is now fixed as far as linux-next is concerned, but any non trivial
> conflicts should be mentioned to your upstream maintainer when your tree
> is submitted for merging. You may also want to consider cooperating
> with the maintainer of the conflicting tree to minimise any particularly
> complex conflicts.
>
> --
> Cheers,
> Stephen Rothwell
>
> diff --cc mm/vmscan.c
> index 04f8671caad9,60335f974803..000000000000
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@@ -4823,18 -4856,22 +4873,17 @@@ void check_move_unevictable_folios(stru
> int pgrescued = 0;
> int i;
>
> - for (i = 0; i < pvec->nr; i++) {
> - struct page *page = pvec->pages[i];
> - struct folio *folio = page_folio(page);
> - int nr_pages;
> -
> - if (PageTransTail(page))
> - continue;
> + for (i = 0; i < fbatch->nr; i++) {
> + struct folio *folio = fbatch->folios[i];
> + int nr_pages = folio_nr_pages(folio);
>
> - nr_pages = folio_nr_pages(folio);
> pgscanned += nr_pages;
>
> - /* block memcg migration while the folio moves between lrus */
> - if (!folio_test_clear_lru(folio))
> + lruvec = folio_lruvec_relock_irq(folio, lruvec);
> + if (!folio_test_lru(folio) || !folio_test_unevictable(folio))
> continue;
>
> - lruvec = folio_lruvec_relock_irq(folio, lruvec);
> - if (folio_evictable(folio) && folio_test_unevictable(folio)) {
> + if (folio_evictable(folio)) {
> lruvec_del_folio(lruvec, folio);
> folio_clear_unevictable(folio);
> lruvec_add_folio(lruvec, folio);
The above fix is no problem. But I have something to confirm since I
do not see the next lines of the code. There is a "folio_set_lru(folio);"
in the end of this if branch, it should be removed as well.
Thanks.
On Wed, 22 Jun 2022 15:22:35 +0800 Muchun Song <[email protected]> wrote:
> > Today's linux-next merge of the mm tree got a conflict in:
> >
> > mm/vmscan.c
> >
> > between commit:
> >
> > 15077be8badc ("vmscan: Add check_move_unevictable_folios()")
>
> Sorry for the conflicts, I didn't see this change in the mm-unstable branch
> yesterday. Based on this commit, I have reworked the following commit
> (see attachment, mainly changes are about check_move_unevictable_folios()).
> Andrew can pick it up if he wants to replace the original patch with
> the new one.
Your comments in
https://lkml.kernel.org/r/[email protected]
make me wonder whether simply dropping cca700a8e695 ("mm: lru: use
lruvec lock to serialize memcg changes") would be best?
On Thu, Jun 23, 2022 at 2:59 AM Andrew Morton <[email protected]> wrote:
>
> On Wed, 22 Jun 2022 15:22:35 +0800 Muchun Song <[email protected]> wrote:
>
> > > Today's linux-next merge of the mm tree got a conflict in:
> > >
> > > mm/vmscan.c
> > >
> > > between commit:
> > >
> > > 15077be8badc ("vmscan: Add check_move_unevictable_folios()")
> >
> > Sorry for the conflicts, I didn't see this change in the mm-unstable branch
> > yesterday. Based on this commit, I have reworked the following commit
> > (see attachment, mainly changes are about check_move_unevictable_folios()).
> > Andrew can pick it up if he wants to replace the original patch with
> > the new one.
>
> Your comments in
> https://lkml.kernel.org/r/[email protected]
> make me wonder whether simply dropping cca700a8e695 ("mm: lru: use
> lruvec lock to serialize memcg changes") would be best?
>
Hi Andrew,
Well, I think we can drop this now. After memcg reparenting work stabilizes,
I will resend this patch again.
Thanks.