The patch titled
Subject: mm/page_alloc: move set_page_refcounted() to callers of get_page_from_freelist()
has been added to the -mm mm-unstable branch. Its filename is
mm-page_alloc-move-set_page_refcounted-to-callers-of-get_page_from_freelist.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-page_alloc-move-set_page_refcounted-to-callers-of-get_page_from_freelist.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@xxxxxxxxxxxxx>
Subject: mm/page_alloc: move set_page_refcounted() to callers of get_page_from_freelist()
Date: Mon, 25 Nov 2024 21:01:38 +0000
In preparation for allocating frozen pages, stop initialising the page
refcount in get_page_from_freelist().
Link: https://lkml.kernel.org/r/20241125210149.2976098-7-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxxx>
Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Cc: Muchun Song <songmuchun@xxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: William Kucharski <william.kucharski@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/page_alloc.c | 25 +++++++++++++++++--------
1 file changed, 17 insertions(+), 8 deletions(-)
--- a/mm/page_alloc.c~mm-page_alloc-move-set_page_refcounted-to-callers-of-get_page_from_freelist
+++ a/mm/page_alloc.c
@@ -3471,7 +3471,6 @@ try_this_zone:
gfp_mask, alloc_flags, ac->migratetype);
if (page) {
prep_new_page(page, order, gfp_mask, alloc_flags);
- set_page_refcounted(page);
/*
* If this is a high-order atomic allocation then check
@@ -3566,6 +3565,8 @@ __alloc_pages_cpuset_fallback(gfp_t gfp_
page = get_page_from_freelist(gfp_mask, order,
alloc_flags, ac);
+ if (page)
+ set_page_refcounted(page);
return page;
}
@@ -3604,8 +3605,10 @@ __alloc_pages_may_oom(gfp_t gfp_mask, un
page = get_page_from_freelist((gfp_mask | __GFP_HARDWALL) &
~__GFP_DIRECT_RECLAIM, order,
ALLOC_WMARK_HIGH|ALLOC_CPUSET, ac);
- if (page)
+ if (page) {
+ set_page_refcounted(page);
goto out;
+ }
/* Coredumps can quickly deplete all memory reserves */
if (current->flags & PF_DUMPCORE)
@@ -3696,10 +3699,8 @@ __alloc_pages_direct_compact(gfp_t gfp_m
count_vm_event(COMPACTSTALL);
/* Prep a captured page if available */
- if (page) {
+ if (page)
prep_new_page(page, order, gfp_mask, alloc_flags);
- set_page_refcounted(page);
- }
/* Try get a page from the freelist if available */
if (!page)
@@ -3708,6 +3709,7 @@ __alloc_pages_direct_compact(gfp_t gfp_m
if (page) {
struct zone *zone = page_zone(page);
+ set_page_refcounted(page);
zone->compact_blockskip_flush = false;
compaction_defer_reset(zone, order, true);
count_vm_event(COMPACTSUCCESS);
@@ -3966,6 +3968,7 @@ retry:
drained = true;
goto retry;
}
+ set_page_refcounted(page);
out:
psi_memstall_leave(&pflags);
@@ -4286,8 +4289,10 @@ restart:
* that first
*/
page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac);
- if (page)
+ if (page) {
+ set_page_refcounted(page);
goto got_pg;
+ }
/*
* For costly allocations, try direct compaction first, as it's likely
@@ -4367,8 +4372,10 @@ retry:
/* Attempt with potentially adjusted zonelist and alloc_flags */
page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac);
- if (page)
+ if (page) {
+ set_page_refcounted(page);
goto got_pg;
+ }
/* Caller is not willing to reclaim, we can't balance anything */
if (!can_direct_reclaim)
@@ -4752,8 +4759,10 @@ struct page *__alloc_pages_noprof(gfp_t
/* First allocation attempt */
page = get_page_from_freelist(alloc_gfp, order, alloc_flags, &ac);
- if (likely(page))
+ if (likely(page)) {
+ set_page_refcounted(page);
goto out;
+ }
alloc_gfp = gfp;
ac.spread_dirty_pages = false;
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-page_alloc-cache-page_zone-result-in-free_unref_page.patch
mm-make-alloc_pages_mpol-static.patch
mm-page_alloc-export-free_frozen_pages-instead-of-free_unref_page.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-post_alloc_hook.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-prep_new_page.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-get_page_from_freelist.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-__alloc_pages_cpuset_fallback.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-__alloc_pages_may_oom.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-__alloc_pages_direct_compact.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-__alloc_pages_direct_reclaim.patch
mm-page_alloc-move-set_page_refcounted-to-callers-of-__alloc_pages_slowpath.patch
mm-page_alloc-move-set_page_refcounted-to-end-of-__alloc_pages.patch
mm-page_alloc-add-__alloc_frozen_pages.patch
mm-mempolicy-add-alloc_frozen_pages.patch
slab-allocate-frozen-pages.patch
