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, 3 insertions, 16 deletions

diff --git a/mm/slab.c b/mm/slab.c
index 30347bd3f19c..e9d90b0da47b 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1360,7 +1360,6 @@ static struct page *kmem_getpages(struct kmem_cache *cachep, gfp_t flags,
 								int nodeid)
 {
 	struct page *page;
-	int nr_pages;
 
 	flags |= cachep->allocflags;
 
@@ -1370,17 +1369,11 @@ static struct page *kmem_getpages(struct kmem_cache *cachep, gfp_t flags,
 		return NULL;
 	}
 
-	if (memcg_charge_slab(page, flags, cachep->gfporder, cachep)) {
+	if (charge_slab_page(page, flags, cachep->gfporder, cachep)) {
 		__free_pages(page, cachep->gfporder);
 		return NULL;
 	}
 
-	nr_pages = (1 << cachep->gfporder);
-	if (cachep->flags & SLAB_RECLAIM_ACCOUNT)
-		mod_lruvec_page_state(page, NR_SLAB_RECLAIMABLE, nr_pages);
-	else
-		mod_lruvec_page_state(page, NR_SLAB_UNRECLAIMABLE, nr_pages);
-
 	__SetPageSlab(page);
 	/* Record if ALLOC_NO_WATERMARKS was set when allocating the slab */
 	if (sk_memalloc_socks() && page_is_pfmemalloc(page))
@@ -1395,12 +1388,6 @@ static struct page *kmem_getpages(struct kmem_cache *cachep, gfp_t flags,
 static void kmem_freepages(struct kmem_cache *cachep, struct page *page)
 {
 	int order = cachep->gfporder;
-	unsigned long nr_freed = (1 << order);
-
-	if (cachep->flags & SLAB_RECLAIM_ACCOUNT)
-		mod_lruvec_page_state(page, NR_SLAB_RECLAIMABLE, -nr_freed);
-	else
-		mod_lruvec_page_state(page, NR_SLAB_UNRECLAIMABLE, -nr_freed);
 
 	BUG_ON(!PageSlab(page));
 	__ClearPageSlabPfmemalloc(page);
@@ -1409,8 +1396,8 @@ static void kmem_freepages(struct kmem_cache *cachep, struct page *page)
 	page->mapping = NULL;
 
 	if (current->reclaim_state)
-		current->reclaim_state->reclaimed_slab += nr_freed;
-	memcg_uncharge_slab(page, order, cachep);
+		current->reclaim_state->reclaimed_slab += 1 << order;
+	uncharge_slab_page(page, order, cachep);
 	__free_pages(page, order);
 }