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 <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Pekka Enberg <[email protected]>
Acked-by: David Rientjes <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/mm/slab_common.c b/mm/slab_common.c
index 48fafb6..735e01a 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -346,15 +346,15 @@
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();
