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

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

The patch titled
     Subject: mm/khugepaged: convert hpage_collapse_scan_pmd() to use folios
has been added to the -mm mm-unstable branch.  Its filename is
     mm-khugepaged-convert-hpage_collapse_scan_pmd-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-hpage_collapse_scan_pmd-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 hpage_collapse_scan_pmd() to use folios
Date: Wed, 18 Oct 2023 13:32:10 -0700

Replaces 5 calls to compound_head(), and removes 1385 bytes of kernel
text.

Link: https://lkml.kernel.org/r/20231018203213.50224-3-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 |   20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

--- a/mm/khugepaged.c~mm-khugepaged-convert-hpage_collapse_scan_pmd-to-use-folios
+++ a/mm/khugepaged.c
@@ -1248,6 +1248,7 @@ static int hpage_collapse_scan_pmd(struc
 	int result = SCAN_FAIL, referenced = 0;
 	int none_or_zero = 0, shared = 0;
 	struct page *page = NULL;
+	struct folio *folio = NULL;
 	unsigned long _address;
 	spinlock_t *ptl;
 	int node = NUMA_NO_NODE, unmapped = 0;
@@ -1334,29 +1335,28 @@ static int hpage_collapse_scan_pmd(struc
 			}
 		}
 
-		page = compound_head(page);
-
+		folio = page_folio(page);
 		/*
 		 * Record which node the original page is from and save this
 		 * information to cc->node_load[].
 		 * Khugepaged will allocate hugepage from the node has the max
 		 * hit record.
 		 */
-		node = page_to_nid(page);
+		node = folio_nid(folio);
 		if (hpage_collapse_scan_abort(node, cc)) {
 			result = SCAN_SCAN_ABORT;
 			goto out_unmap;
 		}
 		cc->node_load[node]++;
-		if (!PageLRU(page)) {
+		if (!folio_test_lru(folio)) {
 			result = SCAN_PAGE_LRU;
 			goto out_unmap;
 		}
-		if (PageLocked(page)) {
+		if (folio_test_locked(folio)) {
 			result = SCAN_PAGE_LOCK;
 			goto out_unmap;
 		}
-		if (!PageAnon(page)) {
+		if (!folio_test_anon(folio)) {
 			result = SCAN_PAGE_ANON;
 			goto out_unmap;
 		}
@@ -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(page)) {
+		if (!is_refcount_suitable(&folio->page)) {
 			result = SCAN_PAGE_COUNT;
 			goto out_unmap;
 		}
@@ -1381,8 +1381,8 @@ static int hpage_collapse_scan_pmd(struc
 		 * enough young pte to justify collapsing the page
 		 */
 		if (cc->is_khugepaged &&
-		    (pte_young(pteval) || page_is_young(page) ||
-		     PageReferenced(page) || mmu_notifier_test_young(vma->vm_mm,
+		    (pte_young(pteval) || folio_test_young(folio) ||
+		     folio_test_referenced(folio) || mmu_notifier_test_young(vma->vm_mm,
 								     address)))
 			referenced++;
 	}
@@ -1404,7 +1404,7 @@ out_unmap:
 		*mmap_locked = false;
 	}
 out:
-	trace_mm_khugepaged_scan_pmd(mm, page, writable, referenced,
+	trace_mm_khugepaged_scan_pmd(mm, &folio->page, writable, referenced,
 				     none_or_zero, result, unmapped);
 	return result;
 }
_

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