[PATCH] tracing: add ACCOUNT flag for allocations from marked slab caches

Vasily Averin
2022-05-16T18:53:38Z

Slab caches marked with SLAB_ACCOUNT force accounting for every
allocation from this cache even if __GFP_ACCOUNT flag is not passed.
Unfortunately, at the moment this flag is not visible in ftrace output,
and this makes it difficult to analyze the accounted allocations.

This patch adds the __GFP_ACCOUNT flag for allocations from slab caches
marked with SLAB_ACCOUNT to the ftrace output.

Signed-off-by: Vasily Averin <vvs@openvz.org>
---
mm/slab.c | 3 +++
mm/slub.c | 3 +++
2 files changed, 6 insertions(+)

diff --git a/mm/slab.c b/mm/slab.c
index 0edb474edef1..4c3da8dfcbdb 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3492,6 +3492,9 @@ void *__kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru,
{
void *ret = slab_alloc(cachep, lru, flags, cachep->object_size, _RET_IP_);

+ if (cachep->flags & SLAB_ACCOUNT)
+ flags |= __GFP_ACCOUNT;
+
trace_kmem_cache_alloc(_RET_IP_, ret,
cachep->object_size, cachep->size, flags);

diff --git a/mm/slub.c b/mm/slub.c
index ed5c2c03a47a..670bbfef9e49 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -3231,6 +3231,9 @@ void *__kmem_cache_alloc_lru(struct kmem_cache *s, struct list_lru *lru,
{
void *ret = slab_alloc(s, lru, gfpflags, _RET_IP_, s->object_size);

+ if (s->flags & SLAB_ACCOUNT)
+ gfpflags |= __GFP_ACCOUNT;
+
trace_kmem_cache_alloc(_RET_IP_, ret, s->object_size,
s->size, gfpflags);

--
2.25.1