slub: Optimize deactivate_slab()

slub: Optimize deactivate_slab()

Since the introduce of unfrozen slabs on cpu partial list, we don't
need to synchronize the slab frozen state under the node list_lock.

The caller of deactivate_slab() and the caller of __slab_free() won't
manipulate the slab list concurrently.

So we can get node list_lock in the last stage if we really need to
manipulate the slab list in this path.

Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>