diff options
| author | Roman Gushchin <roman.gushchin@linux.dev> | 2023-10-19 15:53:43 -0700 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-10-25 16:47:11 -0700 |
| commit | 675d6c9b59e313ca2573c93e8fd87011a99bb8ce (patch) | |
| tree | 1699758fc9f4ffc43fb885516aa28a57fad72ce4 /mm | |
| parent | 1aacbd354313f25c855e662e41c04e2abf71444a (diff) | |
mm: kmem: make memcg keep a reference to the original objcg
Keep a reference to the original objcg object for the entire life of a
memcg structure.
This allows to simplify the synchronization on the kernel memory
allocation paths: pinning a (live) memcg will also pin the corresponding
objcg.
The memory overhead of this change is minimal because object cgroups
usually outlive their corresponding memory cgroups even without this
change, so it's only an additional pointer per memcg.
Link: https://lkml.kernel.org/r/20231019225346.1822282-4-roman.gushchin@linux.dev
Signed-off-by: Roman Gushchin (Cruise) <roman.gushchin@linux.dev>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Acked-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Dennis Zhou <dennis@kernel.org>
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>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/memcontrol.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 96f4c319f025..ff036d5d339d 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3899,6 +3899,8 @@ static int memcg_online_kmem(struct mem_cgroup *memcg) objcg->memcg = memcg; rcu_assign_pointer(memcg->objcg, objcg); + obj_cgroup_get(objcg); + memcg->orig_objcg = objcg; static_branch_enable(&memcg_kmem_online_key); @@ -5406,6 +5408,9 @@ static void __mem_cgroup_free(struct mem_cgroup *memcg) { int node; + if (memcg->orig_objcg) + obj_cgroup_put(memcg->orig_objcg); + for_each_node(node) free_mem_cgroup_per_node_info(memcg, node); kfree(memcg->vmstats); |