+ mm-convert-collapse_huge_page-to-use-a-folio.patch added to mm-unstable branch

+ mm-convert-collapse_huge_page-to-use-a-folio.patch added to mm-unstable branch

[Andrew Morton]

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

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-convert-collapse_huge_page-to-use-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: mm: convert collapse_huge_page() to use a folio
Date: Mon, 11 Dec 2023 16:22:13 +0000

Replace three calls to compound_head() with one.

Link: https://lkml.kernel.org/r/20231211162214.2146080-9-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/khugepaged.c |   15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

--- a/mm/khugepaged.c~mm-convert-collapse_huge_page-to-use-a-folio
+++ a/mm/khugepaged.c
@@ -1090,6 +1090,7 @@ static int collapse_huge_page(struct mm_
 	pmd_t *pmd, _pmd;
 	pte_t *pte;
 	pgtable_t pgtable;
+	struct folio *folio;
 	struct page *hpage;
 	spinlock_t *pmd_ptl, *pte_ptl;
 	int result = SCAN_FAIL;
@@ -1212,13 +1213,13 @@ static int collapse_huge_page(struct mm_
 	if (unlikely(result != SCAN_SUCCEED))
 		goto out_up_write;
 
+	folio = page_folio(hpage);
 	/*
-	 * spin_lock() below is not the equivalent of smp_wmb(), but
-	 * the smp_wmb() inside __SetPageUptodate() can be reused to
-	 * avoid the copy_huge_page writes to become visible after
-	 * the set_pmd_at() write.
+	 * The smp_wmb() inside __folio_mark_uptodate() ensures the
+	 * copy_huge_page writes become visible before the set_pmd_at()
+	 * write.
 	 */
-	__SetPageUptodate(hpage);
+	__folio_mark_uptodate(folio);
 	pgtable = pmd_pgtable(_pmd);
 
 	_pmd = mk_huge_pmd(hpage, vma->vm_page_prot);
@@ -1226,8 +1227,8 @@ static int collapse_huge_page(struct mm_
 
 	spin_lock(pmd_ptl);
 	BUG_ON(!pmd_none(*pmd));
-	page_add_new_anon_rmap(hpage, vma, address);
-	lru_cache_add_inactive_or_unevictable(hpage, vma);
+	folio_add_new_anon_rmap(folio, vma, address);
+	folio_add_lru_vma(folio, vma);
 	pgtable_trans_huge_deposit(mm, pmd, pgtable);
 	set_pmd_at(mm, address, pmd, _pmd);
 	update_mmu_cache_pmd(vma, address, pmd);
_

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

buffer-return-bool-from-grow_dev_folio.patch
buffer-calculate-block-number-inside-folio_init_buffers.patch
buffer-fix-grow_buffers-for-block-size-page_size.patch
buffer-cast-block-to-loff_t-before-shifting-it.patch
buffer-fix-various-functions-for-block-size-page_size.patch
buffer-handle-large-folios-in-__block_write_begin_int.patch
buffer-fix-more-functions-for-block-size-page_size.patch
mm-convert-ksm_might_need_to_copy-to-work-on-folios.patch
mm-simplify-the-assertions-in-unuse_pte.patch
mm-convert-unuse_pte-to-use-a-folio-throughout.patch
mm-remove-some-calls-to-page_add_new_anon_rmap.patch
mm-remove-stale-example-from-comment.patch
mm-remove-references-to-page_add_new_anon_rmap-in-comments.patch
mm-convert-migrate_vma_insert_page-to-use-a-folio.patch
mm-convert-collapse_huge_page-to-use-a-folio.patch
mm-remove-page_add_new_anon_rmap-and-lru_cache_add_inactive_or_unevictable.patch