From: Vladimir Davydov Date: Wed, 4 Jun 2014 23:10:03 +0000 (-0700) Subject: slab: delete cache from list after __kmem_cache_shutdown succeeds X-Git-Tag: firefly_0821_release~176^2~3785^2~16^2~123 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0bd62b1190607e4f1b3c2927ba48672a1cf2a83d;p=firefly-linux-kernel-4.4.55.git slab: delete cache from list after __kmem_cache_shutdown succeeds Currently, on kmem_cache_destroy we delete the cache from the slab_list before __kmem_cache_shutdown, inserting it back to the list on failure. Initially, this was done, because we could release the slab_mutex in __kmem_cache_shutdown to delete sysfs slub entry, but since commit 41a212859a4d ("slub: use sysfs'es release mechanism for kmem_cache") we remove sysfs entry later in kmem_cache_destroy after dropping the slab_mutex, so that no implementation of __kmem_cache_shutdown can ever release the lock. Therefore we can simplify the code a bit by moving list_del after __kmem_cache_shutdown. Signed-off-by: Vladimir Davydov Cc: Christoph Lameter Cc: Pekka Enberg Acked-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/slab_common.c b/mm/slab_common.c index 48fafb61f35e..735e01a0db6f 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -346,15 +346,15 @@ void kmem_cache_destroy(struct kmem_cache *s) if (memcg_cleanup_cache_params(s) != 0) goto out_unlock; - list_del(&s->list); if (__kmem_cache_shutdown(s) != 0) { - list_add(&s->list, &slab_caches); printk(KERN_ERR "kmem_cache_destroy %s: " "Slab cache still has objects\n", s->name); dump_stack(); goto out_unlock; } + list_del(&s->list); + mutex_unlock(&slab_mutex); if (s->flags & SLAB_DESTROY_BY_RCU) rcu_barrier();