linux-kernel - [PATCH 1/2] mm: huge_memory: Convert madvise_free_huge

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 7 Dec 2022 10:34:30 +0800
From:   Kefeng Wang <wangkefeng.wang@...wei.com>
To:     <linux-mm@...ck.org>, Andrew Morton <akpm@...ux-foundation.org>
CC:     "Matthew Wilcox (Oracle)" <willy@...radead.org>,
        <linux-kernel@...r.kernel.org>,
        Kefeng Wang <wangkefeng.wang@...wei.com>
Subject: [PATCH 1/2] mm: huge_memory: Convert madvise_free_huge_pmd to use a folio

Using folios instead of pages removes several calls to compound_head(),

Signed-off-by: Kefeng Wang <wangkefeng.wang@...wei.com>
---
 mm/huge_memory.c | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index abe6cfd92ffa..6e76c770529b 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1603,7 +1603,7 @@ bool madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
 {
 	spinlock_t *ptl;
 	pmd_t orig_pmd;
-	struct page *page;
+	struct folio *folio;
 	struct mm_struct *mm = tlb->mm;
 	bool ret = false;
 
@@ -1623,15 +1623,15 @@ bool madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
 		goto out;
 	}
 
-	page = pmd_page(orig_pmd);
+	folio = pfn_folio(pmd_pfn(orig_pmd));
 	/*
-	 * If other processes are mapping this page, we couldn't discard
-	 * the page unless they all do MADV_FREE so let's skip the page.
+	 * If other processes are mapping this folio, we couldn't discard
+	 * the folio unless they all do MADV_FREE so let's skip the folio.
 	 */
-	if (total_mapcount(page) != 1)
+	if (folio_mapcount(folio) != 1)
 		goto out;
 
-	if (!trylock_page(page))
+	if (!folio_trylock(folio))
 		goto out;
 
 	/*
@@ -1639,17 +1639,17 @@ bool madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
 	 * will deactivate only them.
 	 */
 	if (next - addr != HPAGE_PMD_SIZE) {
-		get_page(page);
+		folio_get(folio);
 		spin_unlock(ptl);
-		split_huge_page(page);
-		unlock_page(page);
-		put_page(page);
+		split_folio(folio);
+		folio_unlock(folio);
+		folio_put(folio);
 		goto out_unlocked;
 	}
 
-	if (PageDirty(page))
-		ClearPageDirty(page);
-	unlock_page(page);
+	if (folio_test_dirty(folio))
+		folio_clear_dirty(folio);
+	folio_unlock(folio);
 
 	if (pmd_young(orig_pmd) || pmd_dirty(orig_pmd)) {
 		pmdp_invalidate(vma, addr, pmd);
@@ -1660,7 +1660,7 @@ bool madvise_free_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
 		tlb_remove_pmd_tlb_entry(tlb, pmd, addr);
 	}
 
-	mark_page_lazyfree(page);
+	mark_page_lazyfree(&folio->page);
 	ret = true;
 out:
 	spin_unlock(ptl);
-- 
2.35.3