On Fri, Nov 27, 2020 at 8:18 AM Roman Gushchin guro@fb.com wrote:
On Thu, Nov 26, 2020 at 09:55:24PM -0800, Shakeel Butt wrote:
On Thu, Nov 26, 2020 at 8:14 PM Roman Gushchin guro@fb.com wrote:
Commit 10befea91b61 ("mm: memcg/slab: use a single set of kmem_caches for all allocations") introduced a regression into the handling of the obj_cgroup_charge() return value. If a non-zero value is returned (indicating of exceeding one of memory.max limits), the allocation should fail, instead of falling back to non-accounted mode.
To make the code more readable, move memcg_slab_pre_alloc_hook() and memcg_slab_post_alloc_hook() calling conditions into bodies of these hooks.
Fixes: 10befea91b61 ("mm: memcg/slab: use a single set of kmem_caches for all allocations") Signed-off-by: Roman Gushchin guro@fb.com Cc: stable@vger.kernel.org
mm/slab.h | 40 ++++++++++++++++++++++++---------------- 1 file changed, 24 insertions(+), 16 deletions(-)
diff --git a/mm/slab.h b/mm/slab.h index 59aeb0d9f11b..5dc89d8fb05e 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -257,22 +257,32 @@ static inline size_t obj_full_size(struct kmem_cache *s) return s->size + sizeof(struct obj_cgroup *); }
-static inline struct obj_cgroup *memcg_slab_pre_alloc_hook(struct kmem_cache *s,
size_t objects,gfp_t flags)+/*
- Returns true if the allocation should fail.
IMO returning false if the allocation should fail makes this more clear. Otherwise the patch looks good to me.
Ok, I agree. Here is an updated version.
Thank you for looking in!
--
From 456ce03f1c91baf5e2441dce0649e09617437fe4 Mon Sep 17 00:00:00 2001 From: Roman Gushchin guro@fb.com Date: Thu, 26 Nov 2020 07:39:57 -0800 Subject: [PATCH v2] mm: memcg/slab: fix obj_cgroup_charge() return value handling
Commit 10befea91b61 ("mm: memcg/slab: use a single set of kmem_caches for all allocations") introduced a regression into the handling of the obj_cgroup_charge() return value. If a non-zero value is returned (indicating of exceeding one of memory.max limits), the allocation should fail, instead of falling back to non-accounted mode.
To make the code more readable, move memcg_slab_pre_alloc_hook() and memcg_slab_post_alloc_hook() calling conditions into bodies of these hooks.
Fixes: 10befea91b61 ("mm: memcg/slab: use a single set of kmem_caches for all allocations") Signed-off-by: Roman Gushchin guro@fb.com Cc: stable@vger.kernel.org
Reviewed-by: Shakeel Butt shakeelb@google.com