The patch titled
Subject: mm/khugepaged: convert __collapse_huge_page_isolate() to use folios
has been added to the -mm mm-unstable branch. Its filename is
mm-khugepaged-convert-__collapse_huge_page_isolate-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-__collapse_huge_page_isolate-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
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: "Vishal Moola (Oracle)" <vishal.moola@xxxxxxxxx>
Subject: mm/khugepaged: convert __collapse_huge_page_isolate() to use folios
Date: Fri, 20 Oct 2023 11:33:27 -0700
Patch series "Some khugepaged folio conversions", v3.
This patchset converts a number of functions to use folios. This cleans
up some khugepaged code and removes a large number of hidden
compound_head() calls.
This patch (of 5):
Replaces 11 calls to compound_head() with 1, and removes 1348 bytes of
kernel text.
Link: https://lkml.kernel.org/r/20231020183331.10770-1-vishal.moola@xxxxxxxxx
Link: https://lkml.kernel.org/r/20231020183331.10770-2-vishal.moola@xxxxxxxxx
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx>
Reviewed-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Yang Shi <shy828301@xxxxxxxxx>
Cc: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/khugepaged.c | 45 +++++++++++++++++++++++----------------------
1 file changed, 23 insertions(+), 22 deletions(-)
--- a/mm/khugepaged.c~mm-khugepaged-convert-__collapse_huge_page_isolate-to-use-folios
+++ a/mm/khugepaged.c
@@ -542,6 +542,7 @@ static int __collapse_huge_page_isolate(
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(
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(
}
}
- 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(
* 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(
* 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(
* 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 @@ next:
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;
}
_
Patches currently in -mm which might be from vishal.moola@xxxxxxxxx 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
