slub: Prepare __slab_free() for unfrozen partial slab out of node partial list

Now the partially empty slub will be frozen when taken out of node partial
list, so the __slab_free() will know from "was_frozen" that the partially
empty slab is not on node partial list and is a cpu or cpu partial slab
of some cpu.

But we will change this, make partial slabs leave the node partial list
with unfrozen state, so we need to change __slab_free() to use the new
slab_test_node_partial() we just introduced.

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>

diff --git a/mm/slub.c b/mm/slub.c
index 6efcbf79fd2dc95541da6fd5b15f080f0b0bc553..18f18fbbd97e1466e1d4456c7c732759164e9e63 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -3631,6 +3631,7 @@ static void __slab_free(struct kmem_cache *s, struct slab *slab,
        unsigned long counters;
        struct kmem_cache_node *n = NULL;
        unsigned long flags;
+       bool on_node_partial;
 
        stat(s, FREE_SLOWPATH);
 
@@ -3678,6 +3679,7 @@ static void __slab_free(struct kmem_cache *s, struct slab *slab,
                                 */
                                spin_lock_irqsave(&n->list_lock, flags);
 
+                               on_node_partial = slab_test_node_partial(slab);
                        }
                }
 
@@ -3706,6 +3708,15 @@ static void __slab_free(struct kmem_cache *s, struct slab *slab,
                return;
        }
 
+       /*
+        * This slab was partially empty but not on the per-node partial list,
+        * in which case we shouldn't manipulate its list, just return.
+        */
+       if (prior && !on_node_partial) {
+               spin_unlock_irqrestore(&n->list_lock, flags);
+               return;
+       }
+
        if (unlikely(!new.inuse && n->nr_partial >= s->min_partial))
                goto slab_empty;