This is a note to let you know that I've just added the patch titled
mm/mempolicy: convert migrate_page_add() to migrate_folio_add()
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mm-mempolicy-convert-migrate_page_add-to-migrate_fol.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 8af17b9c7c656fa77bc58151f3bdf3a5b7283303
Author: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx>
Date: Mon Jan 30 12:18:33 2023 -0800
mm/mempolicy: convert migrate_page_add() to migrate_folio_add()
[ Upstream commit 4a64981dfee9119aa2c1f243b48f34cbbd67779c ]
Replace migrate_page_add() with migrate_folio_add(). migrate_folio_add()
does the same a migrate_page_add() but takes in a folio instead of a page.
This removes a couple of calls to compound_head().
Link: https://lkml.kernel.org/r/20230130201833.27042-7-vishal.moola@xxxxxxxxx
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx>
Reviewed-by: Yin Fengwei <fengwei.yin@xxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Jane Chu <jane.chu@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Stable-dep-of: 24526268f4e3 ("mm: mempolicy: keep VMA walk if both MPOL_MF_STRICT and MPOL_MF_MOVE are specified")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 2ae6c8f18aba1..158b0bcd12fd7 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -414,7 +414,7 @@ static const struct mempolicy_operations mpol_ops[MPOL_MAX] = {
},
};
-static int migrate_page_add(struct page *page, struct list_head *pagelist,
+static int migrate_folio_add(struct folio *folio, struct list_head *foliolist,
unsigned long flags);
struct queue_pages {
@@ -476,7 +476,7 @@ static int queue_folios_pmd(pmd_t *pmd, spinlock_t *ptl, unsigned long addr,
/* go to folio migration */
if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) {
if (!vma_migratable(walk->vma) ||
- migrate_page_add(&folio->page, qp->pagelist, flags)) {
+ migrate_folio_add(folio, qp->pagelist, flags)) {
ret = 1;
goto unlock;
}
@@ -544,7 +544,7 @@ static int queue_folios_pte_range(pmd_t *pmd, unsigned long addr,
* temporary off LRU pages in the range. Still
* need migrate other LRU pages.
*/
- if (migrate_page_add(&folio->page, qp->pagelist, flags))
+ if (migrate_folio_add(folio, qp->pagelist, flags))
has_unmovable = true;
} else
break;
@@ -1012,27 +1012,28 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
}
#ifdef CONFIG_MIGRATION
-/*
- * page migration, thp tail pages can be passed.
- */
-static int migrate_page_add(struct page *page, struct list_head *pagelist,
+static int migrate_folio_add(struct folio *folio, struct list_head *foliolist,
unsigned long flags)
{
- struct page *head = compound_head(page);
/*
- * Avoid migrating a page that is shared with others.
+ * We try to migrate only unshared folios. If it is shared it
+ * is likely not worth migrating.
+ *
+ * To check if the folio is shared, ideally we want to make sure
+ * every page is mapped to the same process. Doing that is very
+ * expensive, so check the estimated mapcount of the folio instead.
*/
- if ((flags & MPOL_MF_MOVE_ALL) || page_mapcount(head) == 1) {
- if (!isolate_lru_page(head)) {
- list_add_tail(&head->lru, pagelist);
- mod_node_page_state(page_pgdat(head),
- NR_ISOLATED_ANON + page_is_file_lru(head),
- thp_nr_pages(head));
+ if ((flags & MPOL_MF_MOVE_ALL) || folio_estimated_sharers(folio) == 1) {
+ if (!folio_isolate_lru(folio)) {
+ list_add_tail(&folio->lru, foliolist);
+ node_stat_mod_folio(folio,
+ NR_ISOLATED_ANON + folio_is_file_lru(folio),
+ folio_nr_pages(folio));
} else if (flags & MPOL_MF_STRICT) {
/*
- * Non-movable page may reach here. And, there may be
- * temporary off LRU pages or non-LRU movable pages.
- * Treat them as unmovable pages since they can't be
+ * Non-movable folio may reach here. And, there may be
+ * temporary off LRU folios or non-LRU movable folios.
+ * Treat them as unmovable folios since they can't be
* isolated, so they can't be moved at the moment. It
* should return -EIO for this case too.
*/
@@ -1224,7 +1225,7 @@ static struct page *new_page(struct page *page, unsigned long start)
}
#else
-static int migrate_page_add(struct page *page, struct list_head *pagelist,
+static int migrate_folio_add(struct folio *folio, struct list_head *foliolist,
unsigned long flags)
{
return -EIO;
