[PATCH 1/6] memcg: move per-node objcg to the read-mostly fields
From: Shakeel Butt <shakeel.butt@linux.dev>
Date: 2026-09-05 03:05:36
Also in:
linux-mm, lkml
Subsystem:
control group - memory resource controller (memcg), the rest · Maintainers:
Johannes Weiner, Michal Hocko, Roman Gushchin, Shakeel Butt, Linus Torvalds
current_obj_cgroup() reads memcg->nodeinfo[nid]->objcg on every accounted allocation. The field sits at the end of struct mem_cgroup_per_node, on the same cache line as lru_zone_size[] and iter. lru_zone_size[] is written on every LRU add and remove, and iter is written on every reclaim iteration. Move objcg next to the other read-mostly pointers at the start of the struct. No functional change. Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> --- include/linux/memcontrol.h | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index f932b1ddda8c..ac575fcc5f1e 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h@@ -94,6 +94,7 @@ struct mem_cgroup_per_node { struct lruvec_stats_percpu __percpu *lruvec_stats_percpu; struct lruvec_stats *lruvec_stats; struct shrinker_info __rcu *shrinker_info; + struct obj_cgroup __rcu *objcg; CACHELINE_PADDING(_pad1_);
@@ -104,11 +105,9 @@ struct mem_cgroup_per_node { struct mem_cgroup_reclaim_iter iter; /* - * objcg is wiped out as a part of the objcg repaprenting process. * orig_objcg preserves a pointer (and a reference) to the original - * objcg until the end of live of memcg. + * objcg until the end of life of memcg. */ - struct obj_cgroup __rcu *objcg; struct obj_cgroup *orig_objcg; /* list of inherited objcgs, protected by objcg_lock */ struct list_head objcg_list;
--
2.53.0-Meta