+ mm-khugepaged-convert-is_refcount_suitable-to-use-folios.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm/khugepaged: convert is_refcount_suitable() to use folios
has been added to the -mm mm-unstable branch.  Its filename is
     mm-khugepaged-convert-is_refcount_suitable-to-use-folios.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-khugepaged-convert-is_refcount_suitable-to-use-folios.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: "Vishal Moola (Oracle)" <vishal.moola@gmail.com>
Subject: mm/khugepaged: convert is_refcount_suitable() to use folios
Date: Wed, 18 Oct 2023 13:32:11 -0700

Both callers of is_refcount_suitable() have been converted to use folios,
so convert it to take in a folio.  Both callers only operate on head pages
of folios so mapcount/refcount conversions here are trivial.

Removes 3 calls to compound head, and removes 315 bytes of kernel text.

Link: https://lkml.kernel.org/r/20231018203213.50224-4-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/khugepaged.c |   14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

--- a/mm/khugepaged.c~mm-khugepaged-convert-is_refcount_suitable-to-use-folios
+++ a/mm/khugepaged.c
@@ -524,15 +524,15 @@ static void release_pte_pages(pte_t *pte
 	}
 }
 
-static bool is_refcount_suitable(struct page *page)
+static bool is_refcount_suitable(struct folio *folio)
 {
 	int expected_refcount;
 
-	expected_refcount = total_mapcount(page);
-	if (PageSwapCache(page))
-		expected_refcount += compound_nr(page);
+	expected_refcount = folio_mapcount(folio);
+	if (folio_test_swapcache(folio))
+		expected_refcount += folio_nr_pages(folio);
 
-	return page_count(page) == expected_refcount;
+	return folio_ref_count(folio) == expected_refcount;
 }
 
 static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
@@ -625,7 +625,7 @@ static int __collapse_huge_page_isolate(
 		 * but not from this process. The other process cannot write to
 		 * the page, only trigger CoW.
 		 */
-		if (!is_refcount_suitable(&folio->page)) {
+		if (!is_refcount_suitable(folio)) {
 			folio_unlock(folio);
 			result = SCAN_PAGE_COUNT;
 			goto out;
@@ -1371,7 +1371,7 @@ static int hpage_collapse_scan_pmd(struc
 		 * has excessive GUP pins (i.e. 512).  Anyway the same check
 		 * will be done again later the risk seems low.
 		 */
-		if (!is_refcount_suitable(&folio->page)) {
+		if (!is_refcount_suitable(folio)) {
 			result = SCAN_PAGE_COUNT;
 			goto out_unmap;
 		}
_

Patches currently in -mm which might be from vishal.moola@gmail.com are

mm-khugepaged-convert-__collapse_huge_page_isolate-to-use-folios.patch
mm-khugepaged-convert-hpage_collapse_scan_pmd-to-use-folios.patch
mm-khugepaged-convert-is_refcount_suitable-to-use-folios.patch
mm-khugepaged-convert-alloc_charge_hpage-to-use-folios.patch
mm-khugepaged-convert-collapse_pte_mapped_thp-to-use-folios.patch
mm-khugepaged-convert-collapse_pte_mapped_thp-to-use-folios-fix.patch