From 964d4bd370d559d9bd8e4abc139e85d2753956fb Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Thu, 6 Aug 2020 23:20:56 -0700 Subject: mm: memcg/slab: save obj_cgroup for non-root slab objects Store the obj_cgroup pointer in the corresponding place of page->obj_cgroups for each allocated non-root slab object. Make sure that each allocated object holds a reference to obj_cgroup. Objcg pointer is obtained from the memcg->objcg dereferencing in memcg_kmem_get_cache() and passed from pre_alloc_hook to post_alloc_hook. Then in case of successful allocation(s) it's getting stored in the page->obj_cgroups vector. The objcg obtaining part look a bit bulky now, but it will be simplified by next commits in the series. Signed-off-by: Roman Gushchin Signed-off-by: Andrew Morton Reviewed-by: Vlastimil Babka Reviewed-by: Shakeel Butt Cc: Christoph Lameter Cc: Johannes Weiner Cc: Michal Hocko Cc: Tejun Heo Link: http://lkml.kernel.org/r/20200623174037.3951353-9-guro@fb.com Signed-off-by: Linus Torvalds --- mm/slab.h | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 54 insertions(+), 6 deletions(-) (limited to 'mm/slab.h') diff --git a/mm/slab.h b/mm/slab.h index 9f78e3167f19..d4f9fc93546f 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -470,6 +470,41 @@ static inline void memcg_free_page_obj_cgroups(struct page *page) page->obj_cgroups = NULL; } +static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, + struct obj_cgroup *objcg, + size_t size, void **p) +{ + struct page *page; + unsigned long off; + size_t i; + + for (i = 0; i < size; i++) { + if (likely(p[i])) { + page = virt_to_head_page(p[i]); + off = obj_to_index(s, page, p[i]); + obj_cgroup_get(objcg); + page_obj_cgroups(page)[off] = objcg; + } + } + obj_cgroup_put(objcg); + memcg_kmem_put_cache(s); +} + +static inline void memcg_slab_free_hook(struct kmem_cache *s, struct page *page, + void *p) +{ + struct obj_cgroup *objcg; + unsigned int off; + + if (!memcg_kmem_enabled() || is_root_cache(s)) + return; + + off = obj_to_index(s, page, p); + objcg = page_obj_cgroups(page)[off]; + page_obj_cgroups(page)[off] = NULL; + obj_cgroup_put(objcg); +} + extern void slab_init_memcg_params(struct kmem_cache *); extern void memcg_link_cache(struct kmem_cache *s, struct mem_cgroup *memcg); @@ -529,6 +564,17 @@ static inline void memcg_free_page_obj_cgroups(struct page *page) { } +static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s, + struct obj_cgroup *objcg, + size_t size, void **p) +{ +} + +static inline void memcg_slab_free_hook(struct kmem_cache *s, struct page *page, + void *p) +{ +} + static inline void slab_init_memcg_params(struct kmem_cache *s) { } @@ -631,7 +677,8 @@ static inline size_t slab_ksize(const struct kmem_cache *s) } static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s, - gfp_t flags) + struct obj_cgroup **objcgp, + size_t size, gfp_t flags) { flags &= gfp_allowed_mask; @@ -645,13 +692,14 @@ static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s, if (memcg_kmem_enabled() && ((flags & __GFP_ACCOUNT) || (s->flags & SLAB_ACCOUNT))) - return memcg_kmem_get_cache(s); + return memcg_kmem_get_cache(s, objcgp); return s; } -static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags, - size_t size, void **p) +static inline void slab_post_alloc_hook(struct kmem_cache *s, + struct obj_cgroup *objcg, + gfp_t flags, size_t size, void **p) { size_t i; @@ -663,8 +711,8 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags, s->flags, flags); } - if (memcg_kmem_enabled()) - memcg_kmem_put_cache(s); + if (memcg_kmem_enabled() && !is_root_cache(s)) + memcg_slab_post_alloc_hook(s, objcg, size, p); } #ifndef CONFIG_SLOB -- cgit