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Subject[PATCH 3/3] mm: kmem: switch to static_branch_likely() in memcg_kmem_enabled()
Date
Currently memcg_kmem_enabled() is optimized for the kernel memory
accounting being off. It was so for a long time, and arguably the
reason behind was that the kernel memory accounting was initially an
opt-in feature. However, now it's on by default on both cgroup v1
and cgroup v2, and it's on for all cgroups. So let's switch over
to static_branch_likely() to reflect this fact.

Unlikely there is a significant performance difference, as the cost
of a memory allocation and its accounting significantly exceeds the
cost of a jump. However, the conversion makes the code look more
logically.

Signed-off-by: Roman Gushchin <guro@fb.com>
---
include/linux/memcontrol.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index b8f52a3fed90..ab9322215b2e 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -1456,7 +1456,7 @@ void memcg_put_cache_ids(void);

static inline bool memcg_kmem_enabled(void)
{
- return static_branch_unlikely(&memcg_kmem_enabled_key);
+ return static_branch_likely(&memcg_kmem_enabled_key);
}

static inline bool memcg_kmem_bypass(void)
--
2.26.2
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