The patch titled
Subject: mm: page_counters: initialize usage using ATOMIC_LONG_INIT() macro
has been added to the -mm mm-unstable branch. Its filename is
mm-page_counters-initialize-usage-using-atomic_long_init-macro.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-page_counters-initialize-usage-using-atomic_long_init-macro.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: Roman Gushchin <roman.gushchin@xxxxxxxxx>
Subject: mm: page_counters: initialize usage using ATOMIC_LONG_INIT() macro
Date: Fri, 26 Jul 2024 20:31:10 +0000
When a page_counter structure is initialized, there is no need to use an
atomic set operation to initialize the usage counter because at this point
the structure is not visible to anybody else. ATOMIC_LONG_INIT() is what
should be used in such cases.
Link: https://lkml.kernel.org/r/20240726203110.1577216-4-roman.gushchin@xxxxxxxxx
Signed-off-by: Roman Gushchin <roman.gushchin@xxxxxxxxx>
Acked-by: Shakeel Butt <shakeel.butt@xxxxxxxxx>
Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Muchun Song <songmuchun@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/page_counter.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/include/linux/page_counter.h~mm-page_counters-initialize-usage-using-atomic_long_init-macro
+++ a/include/linux/page_counter.h
@@ -53,7 +53,7 @@ static inline void page_counter_init(str
struct page_counter *parent,
bool protection_support)
{
- atomic_long_set(&counter->usage, 0);
+ counter->usage = (atomic_long_t)ATOMIC_LONG_INIT(0);
counter->max = PAGE_COUNTER_MAX;
counter->parent = parent;
counter->protection_support = protection_support;
_
Patches currently in -mm which might be from roman.gushchin@xxxxxxxxx are
mm-memcg-dont-call-propagate_protected_usage-needlessly.patch
mm-page_counters-put-page_counter_calculate_protection-under-config_memcg.patch
mm-page_counters-initialize-usage-using-atomic_long_init-macro.patch
