From: Roman Gushchin <guro@xxxxxx>
Subject: mm: memcg: fix obsolete code comments
This patch fixes/removes some obsolete comments in the code related
to the kernel memory accounting:
- kmem_cache->memcg_params.memcg_caches has been removed
by commit 9855609bde03 ("mm: memcg/slab: use a single set of
kmem_caches for all accounted allocations")
- memcg->kmemcg_id is not used as a gate for kmem accounting since
commit 0b8f73e10428 ("mm: memcontrol: clean up alloc, online,
offline, free functions")
Link: https://lkml.kernel.org/r/20201110184615.311974-1-guro@xxxxxx
Signed-off-by: Roman Gushchin <guro@xxxxxx>
Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Reviewed-by: Shakeel Butt <shakeelb@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/memcontrol.h | 6 ++----
mm/memcontrol.c | 6 ------
2 files changed, 2 insertions(+), 10 deletions(-)
--- a/include/linux/memcontrol.h~mm-memcg-fix-obsolete-code-comments
+++ a/include/linux/memcontrol.h
@@ -296,7 +296,6 @@ struct mem_cgroup {
int tcpmem_pressure;
#ifdef CONFIG_MEMCG_KMEM
- /* Index in the kmem_cache->memcg_params.memcg_caches array */
int kmemcg_id;
enum memcg_kmem_state kmem_state;
struct obj_cgroup __rcu *objcg;
@@ -1562,9 +1561,8 @@ static inline void memcg_kmem_uncharge(s
}
/*
- * helper for accessing a memcg's index. It will be used as an index in the
- * child cache array in kmem_cache, and also to derive its name. This function
- * will return -1 when this is not a kmem-limited memcg.
+ * A helper for accessing memcg's kmem_id, used for getting
+ * corresponding LRU lists.
*/
static inline int memcg_cache_id(struct mem_cgroup *memcg)
{
--- a/mm/memcontrol.c~mm-memcg-fix-obsolete-code-comments
+++ a/mm/memcontrol.c
@@ -3703,12 +3703,6 @@ static int memcg_online_kmem(struct mem_
static_branch_enable(&memcg_kmem_enabled_key);
- /*
- * A memory cgroup is considered kmem-online as soon as it gets
- * kmemcg_id. Setting the id after enabling static branching will
- * guarantee no one starts accounting before all call sites are
- * patched.
- */
memcg->kmemcg_id = memcg_id;
memcg->kmem_state = KMEM_ONLINE;
_
