+ ksm-convert-should_skip_rmap_item-to-take-a-folio.patch added to mm-unstable branch

+ ksm-convert-should_skip_rmap_item-to-take-a-folio.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: ksm: convert should_skip_rmap_item() to take a folio
has been added to the -mm mm-unstable branch.  Its filename is
     ksm-convert-should_skip_rmap_item-to-take-a-folio.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/ksm-convert-should_skip_rmap_item-to-take-a-folio.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: ksm: convert should_skip_rmap_item() to take a folio
Date: Wed, 2 Oct 2024 16:25:29 +0100

Remove a call to PageKSM() by passing the folio containing tmp_page to
should_skip_rmap_item.  Removes a hidden call to compound_head().

Link: https://lkml.kernel.org/r/20241002152533.1350629-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Alex Shi <alexs@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/ksm.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/mm/ksm.c~ksm-convert-should_skip_rmap_item-to-take-a-folio
+++ a/mm/ksm.c
@@ -2401,10 +2401,10 @@ static unsigned int skip_age(rmap_age_t
 /*
  * Determines if a page should be skipped for the current scan.
  *
- * @page: page to check
+ * @folio: folio containing the page to check
  * @rmap_item: associated rmap_item of page
  */
-static bool should_skip_rmap_item(struct page *page,
+static bool should_skip_rmap_item(struct folio *folio,
 				  struct ksm_rmap_item *rmap_item)
 {
 	rmap_age_t age;
@@ -2417,7 +2417,7 @@ static bool should_skip_rmap_item(struct
 	 * will essentially ignore them, but we still have to process them
 	 * properly.
 	 */
-	if (PageKsm(page))
+	if (folio_test_ksm(folio))
 		return false;
 
 	age = rmap_item->age;
@@ -2560,7 +2560,7 @@ next_mm:
 					ksm_scan.rmap_list =
 							&rmap_item->rmap_list;
 
-					if (should_skip_rmap_item(tmp_page, rmap_item)) {
+					if (should_skip_rmap_item(folio, rmap_item)) {
 						folio_put(folio);
 						goto next_page;
 					}
_

Patches currently in -mm which might be from willy@infradead.org are

ksm-use-a-folio-in-try_to_merge_one_page.patch
ksm-convert-cmp_and_merge_page-to-use-a-folio.patch
ksm-convert-should_skip_rmap_item-to-take-a-folio.patch
mm-add-pageanonnotksm.patch
mm-remove-pageksm.patch