On 5/28/20 12:34 AM, Roman Gushchin wrote: > diff --git a/mm/slab.h b/mm/slab.h > index c49a863adb63..57b425d623e5 100644 > --- a/mm/slab.h > +++ b/mm/slab.h ... > @@ -526,8 +430,7 @@ static inline struct kmem_cache *cache_from_obj(struct > kmem_cache *s, void *x) > * When kmemcg is not being used, both assignments should return the > * same value. but we don't want to pay the assignment price in that > * case. If it is not compiled in, the compiler should be smart enough > - * to not do even the assignment. In that case, slab_equal_or_root > - * will also be a constant. > + * to not do even the assignment. > */ > if (!memcg_kmem_enabled() &&
Just realized that this test can go away - we don't have to call virt_to_cache() due to kmemcg if there is just a single cache. > !IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && > @@ -535,7 +438,7 @@ static inline struct kmem_cache *cache_from_obj(struct > kmem_cache *s, void *x) > return s; > > cachep = virt_to_cache(x); > - WARN_ONCE(cachep && !slab_equal_or_root(cachep, s), > + WARN_ONCE(cachep && cachep != s, > "%s: Wrong slab cache. %s but object is from %s\n", > __func__, s->name, cachep->name); > return cachep;
