diff options
| author | Roman Gushchin <roman.gushchin@linux.dev> | 2024-07-01 18:59:32 +0000 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-07-10 12:14:54 -0700 |
| commit | 6df13230b612af81ce04f20bb37a02e58ef71925 (patch) | |
| tree | 6eb98f72f91549532fff2c387e40d7c7a9591318 | |
| parent | mm: memcg: drop obsolete cache line padding in struct mem_cgroup (diff) | |
| download | linux-6df13230b612af81ce04f20bb37a02e58ef71925.tar.gz linux-6df13230b612af81ce04f20bb37a02e58ef71925.zip | |
mm: memcg: add cache line padding to mem_cgroup_per_node
Memcg v1-specific fields serve a buffer function between read-mostly and
update often parts of the mem_cgroup_per_node structure. If
CONFIG_MEMCG_V1 is not set and these fields are not present, an explicit
cacheline padding is needed.
Link: https://lkml.kernel.org/r/20240701185932.704807-2-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Suggested-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | include/linux/memcontrol.h | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 8b5b3ddeba05..60418934827c 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -95,14 +95,16 @@ struct mem_cgroup_per_node { #ifdef CONFIG_MEMCG_V1 /* * Memcg-v1 only stuff in middle as buffer between read mostly fields - * and update often fields to avoid false sharing. Once v1 stuff is - * moved in a separate struct, an explicit padding is needed. + * and update often fields to avoid false sharing. If v1 stuff is + * not present, an explicit padding is needed. */ struct rb_node tree_node; /* RB tree node */ unsigned long usage_in_excess;/* Set to the value by which */ /* the soft limit is exceeded*/ bool on_tree; +#else + CACHELINE_PADDING(_pad1_); #endif /* Fields which get updated often at the end. */ |