From 9855609bde03e2472b99a95e869d29ee1e78a751 Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Thu, 6 Aug 2020 23:21:10 -0700 Subject: mm: memcg/slab: use a single set of kmem_caches for all accounted allocations This is fairly big but mostly red patch, which makes all accounted slab allocations use a single set of kmem_caches instead of creating a separate set for each memory cgroup. Because the number of non-root kmem_caches is now capped by the number of root kmem_caches, there is no need to shrink or destroy them prematurely. They can be perfectly destroyed together with their root counterparts. This allows to dramatically simplify the management of non-root kmem_caches and delete a ton of code. This patch performs the following changes: 1) introduces memcg_params.memcg_cache pointer to represent the kmem_cache which will be used for all non-root allocations 2) reuses the existing memcg kmem_cache creation mechanism to create memcg kmem_cache on the first allocation attempt 3) memcg kmem_caches are named -memcg, e.g. dentry-memcg 4) simplifies memcg_kmem_get_cache() to just return memcg kmem_cache or schedule it's creation and return the root cache 5) removes almost all non-root kmem_cache management code (separate refcounter, reparenting, shrinking, etc) 6) makes slab debugfs to display root_mem_cgroup css id and never show :dead and :deact flags in the memcg_slabinfo attribute. Following patches in the series will simplify the kmem_cache creation. 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/20200623174037.3951353-13-guro@fb.com Signed-off-by: Linus Torvalds --- mm/slab.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) (limited to 'mm/slab.c') diff --git a/mm/slab.c b/mm/slab.c index 1e90b67735aa..0dd6956585dc 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -1249,7 +1249,7 @@ void __init kmem_cache_init(void) nr_node_ids * sizeof(struct kmem_cache_node *), SLAB_HWCACHE_ALIGN, 0, 0); list_add(&kmem_cache->list, &slab_caches); - memcg_link_cache(kmem_cache, NULL); + memcg_link_cache(kmem_cache); slab_state = PARTIAL; /* @@ -2253,17 +2253,6 @@ int __kmem_cache_shrink(struct kmem_cache *cachep) return (ret ? 1 : 0); } -#ifdef CONFIG_MEMCG -void __kmemcg_cache_deactivate(struct kmem_cache *cachep) -{ - __kmem_cache_shrink(cachep); -} - -void __kmemcg_cache_deactivate_after_rcu(struct kmem_cache *s) -{ -} -#endif - int __kmem_cache_shutdown(struct kmem_cache *cachep) { return __kmem_cache_shrink(cachep); @@ -3872,7 +3861,8 @@ static int do_tune_cpucache(struct kmem_cache *cachep, int limit, return ret; lockdep_assert_held(&slab_mutex); - for_each_memcg_cache(c, cachep) { + c = memcg_cache(cachep); + if (c) { /* return value determined by the root cache only */ __do_tune_cpucache(c, limit, batchcount, shared, gfp); } -- cgit 1.4.1