On Wed, Apr 11, 2018 at 08:44:23AM -0500, Christopher Lameter wrote: > > +++ b/mm/slub.c > > @@ -2725,7 +2726,7 @@ static __always_inline void *slab_alloc_node(struct kmem_cache *s, > > stat(s, ALLOC_FASTPATH); > > } > > > > - if (unlikely(gfpflags & __GFP_ZERO) && object) > > + if (unlikely(gfpflags & __GFP_ZERO) && object && slab_no_ctor(s)) > > memset(object, 0, s->object_size); > > > > slab_post_alloc_hook(s, gfpflags, 1, &object); > > Please put this in a code path that is enabled by specifying > > slub_debug > > on the kernel command line. I don't understand. First, I had: if (unlikely(gfpflags & __GFP_ZERO) && object && !WARN_ON_ONCE(s->ctor)) and you didn't like that because it was putting checking into a (semi)fast path. Now you want me to add a check for slub_debug somewhere? I dont see an existing one I can leverage that will hit on every allocation. Perhaps I'm missing something.
