| 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
| ||
|
Message-ID: <CAHbLzkphG4XrV91WjeY9fuurTXcCnyev+RKbg+nzZk6hgZ=Kcg@mail.gmail.com>
Date: Tue, 24 Oct 2023 10:37:52 -0700
From: Yang Shi <shy828301@...il.com>
To: "Vishal Moola (Oracle)" <vishal.moola@...il.com>
Cc: linux-mm@...ck.org, linux-kernel@...r.kernel.org,
akpm@...ux-foundation.org, Matthew Wilcox <willy@...radead.org>
Subject: Re: [PATCH v3 1/5] mm/khugepaged: Convert __collapse_huge_page_isolate()
to use folios
On Fri, Oct 20, 2023 at 11:33 AM Vishal Moola (Oracle)
<vishal.moola@...il.com> wrote:
>
> Replaces 11 calls to compound_head() with 1, and removes 1348 bytes of
> kernel text.
>
> Reviewed-by: Matthew Wilcox (Oracle) <willy@...radead.org>
> Signed-off-by: Vishal Moola (Oracle) <vishal.moola@...il.com>
Reviewed-by: Yang Shi <shy828301@...il.com>
> ---
> mm/khugepaged.c | 45 +++++++++++++++++++++++----------------------
> 1 file changed, 23 insertions(+), 22 deletions(-)
>
> diff --git a/mm/khugepaged.c b/mm/khugepaged.c
> index 88433cc25d8a..500756604488 100644
> --- a/mm/khugepaged.c
> +++ b/mm/khugepaged.c
> @@ -542,6 +542,7 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
> struct list_head *compound_pagelist)
> {
> struct page *page = NULL;
> + struct folio *folio = NULL;
> pte_t *_pte;
> int none_or_zero = 0, shared = 0, result = SCAN_FAIL, referenced = 0;
> bool writable = false;
> @@ -576,7 +577,8 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
> goto out;
> }
>
> - VM_BUG_ON_PAGE(!PageAnon(page), page);
> + folio = page_folio(page);
> + VM_BUG_ON_FOLIO(!folio_test_anon(folio), folio);
>
> if (page_mapcount(page) > 1) {
> ++shared;
> @@ -588,16 +590,15 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
> }
> }
>
> - if (PageCompound(page)) {
> - struct page *p;
> - page = compound_head(page);
> + if (folio_test_large(folio)) {
> + struct folio *f;
>
> /*
> * Check if we have dealt with the compound page
> * already
> */
> - list_for_each_entry(p, compound_pagelist, lru) {
> - if (page == p)
> + list_for_each_entry(f, compound_pagelist, lru) {
> + if (folio == f)
> goto next;
> }
> }
> @@ -608,7 +609,7 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
> * is needed to serialize against split_huge_page
> * when invoked from the VM.
> */
> - if (!trylock_page(page)) {
> + if (!folio_trylock(folio)) {
> result = SCAN_PAGE_LOCK;
> goto out;
> }
> @@ -624,8 +625,8 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
> * but not from this process. The other process cannot write to
> * the page, only trigger CoW.
> */
> - if (!is_refcount_suitable(page)) {
> - unlock_page(page);
> + if (!is_refcount_suitable(&folio->page)) {
> + folio_unlock(folio);
> result = SCAN_PAGE_COUNT;
> goto out;
> }
> @@ -634,27 +635,27 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
> * Isolate the page to avoid collapsing an hugepage
> * currently in use by the VM.
> */
> - if (!isolate_lru_page(page)) {
> - unlock_page(page);
> + if (!folio_isolate_lru(folio)) {
> + folio_unlock(folio);
> result = SCAN_DEL_PAGE_LRU;
> goto out;
> }
> - mod_node_page_state(page_pgdat(page),
> - NR_ISOLATED_ANON + page_is_file_lru(page),
> - compound_nr(page));
> - VM_BUG_ON_PAGE(!PageLocked(page), page);
> - VM_BUG_ON_PAGE(PageLRU(page), page);
> + node_stat_mod_folio(folio,
> + NR_ISOLATED_ANON + folio_is_file_lru(folio),
> + folio_nr_pages(folio));
> + VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio);
> + VM_BUG_ON_FOLIO(folio_test_lru(folio), folio);
>
> - if (PageCompound(page))
> - list_add_tail(&page->lru, compound_pagelist);
> + if (folio_test_large(folio))
> + list_add_tail(&folio->lru, compound_pagelist);
> next:
> /*
> * If collapse was initiated by khugepaged, check that there is
> * 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++;
>
> @@ -668,13 +669,13 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma,
> result = SCAN_LACK_REFERENCED_PAGE;
> } else {
> result = SCAN_SUCCEED;
> - trace_mm_collapse_huge_page_isolate(page, none_or_zero,
> + trace_mm_collapse_huge_page_isolate(&folio->page, none_or_zero,
> referenced, writable, result);
> return result;
> }
> out:
> release_pte_pages(pte, _pte, compound_pagelist);
> - trace_mm_collapse_huge_page_isolate(page, none_or_zero,
> + trace_mm_collapse_huge_page_isolate(&folio->page, none_or_zero,
> referenced, writable, result);
> return result;
> }
> --
> 2.40.1
>
Powered by blists - more mailing lists