From d1b2cf6cb84a9bd0de6f151512648dd1af82f80f Mon Sep 17 00:00:00 2001 From: Bharata B Rao Date: Tue, 13 Oct 2020 16:53:09 -0700 Subject: [PATCH] mm: memcg/slab: uncharge during kmem_cache_free_bulk() Object cgroup charging is done for all the objects during allocation, but during freeing, uncharging ends up happening for only one object in the case of bulk allocation/freeing. Fix this by having a separate call to uncharge all the objects from kmem_cache_free_bulk() and by modifying memcg_slab_free_hook() to take care of bulk uncharging. Fixes: 964d4bd370d5 ("mm: memcg/slab: save obj_cgroup for non-root slab objects" Signed-off-by: Bharata B Rao Signed-off-by: Andrew Morton Acked-by: Roman Gushchin Cc: Christoph Lameter Cc: David Rientjes Cc: Joonsoo Kim Cc: Vlastimil Babka Cc: Shakeel Butt Cc: Johannes Weiner Cc: Michal Hocko Cc: Tejun Heo Cc: Link: https://lkml.kernel.org/r/20201009060423.390479-1-bharata@linux.ibm.com Signed-off-by: Linus Torvalds --- mm/slab.c | 2 +- mm/slab.h | 42 +++++++++++++++++++++++++++--------------- mm/slub.c | 3 ++- 3 files changed, 30 insertions(+), 17 deletions(-) diff --git a/mm/slab.c b/mm/slab.c index 04bc6a6c48eb..399a9d185b0f 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -3438,7 +3438,7 @@ void ___cache_free(struct kmem_cache *cachep, void *objp, memset(objp, 0, cachep->object_size); kmemleak_free_recursive(objp, cachep->flags); objp = cache_free_debugcheck(cachep, objp, caller); - memcg_slab_free_hook(cachep, virt_to_head_page(objp), objp); + memcg_slab_free_hook(cachep, &objp, 1); /* * Skip calling cache_free_alien() when the platform is not numa. diff --git a/mm/slab.h b/mm/slab.h index 6cc323f1313a..6dd4b702888a 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -345,30 +345,42 @@ static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, obj_cgroup_put(objcg); } -static inline void memcg_slab_free_hook(struct kmem_cache *s, struct page *page, - void *p) +static inline void memcg_slab_free_hook(struct kmem_cache *s_orig, + void **p, int objects) { + struct kmem_cache *s; struct obj_cgroup *objcg; + struct page *page; unsigned int off; + int i; if (!memcg_kmem_enabled()) return; - if (!page_has_obj_cgroups(page)) - return; + for (i = 0; i < objects; i++) { + if (unlikely(!p[i])) + continue; - off = obj_to_index(s, page, p); - objcg = page_obj_cgroups(page)[off]; - page_obj_cgroups(page)[off] = NULL; + page = virt_to_head_page(p[i]); + if (!page_has_obj_cgroups(page)) + continue; - if (!objcg) - return; + if (!s_orig) + s = page->slab_cache; + else + s = s_orig; - obj_cgroup_uncharge(objcg, obj_full_size(s)); - mod_objcg_state(objcg, page_pgdat(page), cache_vmstat_idx(s), - -obj_full_size(s)); + off = obj_to_index(s, page, p[i]); + objcg = page_obj_cgroups(page)[off]; + if (!objcg) + continue; - obj_cgroup_put(objcg); + page_obj_cgroups(page)[off] = NULL; + obj_cgroup_uncharge(objcg, obj_full_size(s)); + mod_objcg_state(objcg, page_pgdat(page), cache_vmstat_idx(s), + -obj_full_size(s)); + obj_cgroup_put(objcg); + } } #else /* CONFIG_MEMCG_KMEM */ @@ -406,8 +418,8 @@ static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, { } -static inline void memcg_slab_free_hook(struct kmem_cache *s, struct page *page, - void *p) +static inline void memcg_slab_free_hook(struct kmem_cache *s, + void **p, int objects) { } #endif /* CONFIG_MEMCG_KMEM */ diff --git a/mm/slub.c b/mm/slub.c index f05900186c0b..61d0d2968413 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -3095,7 +3095,7 @@ static __always_inline void do_slab_free(struct kmem_cache *s, struct kmem_cache_cpu *c; unsigned long tid; - memcg_slab_free_hook(s, page, head); + memcg_slab_free_hook(s, &head, 1); redo: /* * Determine the currently cpus per cpu slab. @@ -3257,6 +3257,7 @@ void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p) if (WARN_ON(!size)) return; + memcg_slab_free_hook(s, p, size); do { struct detached_freelist df;