mm: memcg/slab: unify SLAB and SLUB page accounting

Currently the page accounting code is duplicated in SLAB and SLUB
internals.  Let's move it into new (un)charge_slab_page helpers in the
slab_common.c file.  These helpers will be responsible for statistics
(global and memcg-aware) and memcg charging.  So they are replacing direct
memcg_(un)charge_slab() calls.

Link: http://lkml.kernel.org/r/20190611231813.3148843-6-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Waiman Long <longman@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 25 insertions, 0 deletions

diff --git a/mm/slab.h b/mm/slab.h
index dc83583ee9dd..46623a576a3c 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -205,6 +205,12 @@ ssize_t slabinfo_write(struct file *file, const char __user *buffer,
 void __kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);
 int __kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);
 
+static inline int cache_vmstat_idx(struct kmem_cache *s)
+{
+	return (s->flags & SLAB_RECLAIM_ACCOUNT) ?
+		NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE;
+}
+
 #ifdef CONFIG_MEMCG_KMEM
 
 /* List of all root caches. */
@@ -361,6 +367,25 @@ static inline struct kmem_cache *virt_to_cache(const void *obj)
 	return page->slab_cache;
 }
 
+static __always_inline int charge_slab_page(struct page *page,
+					    gfp_t gfp, int order,
+					    struct kmem_cache *s)
+{
+	int ret = memcg_charge_slab(page, gfp, order, s);
+
+	if (!ret)
+		mod_lruvec_page_state(page, cache_vmstat_idx(s), 1 << order);
+
+	return ret;
+}
+
+static __always_inline void uncharge_slab_page(struct page *page, int order,
+					       struct kmem_cache *s)
+{
+	mod_lruvec_page_state(page, cache_vmstat_idx(s), -(1 << order));
+	memcg_uncharge_slab(page, order, s);
+}
+
 static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
 {
 	struct kmem_cache *cachep;