On Mon, Jun 17, 2024 at 06:57:45PM +0200, Jason A. Donenfeld wrote: > On Mon, Jun 17, 2024 at 06:42:23PM +0200, Uladzislau Rezki wrote: > > On Mon, Jun 17, 2024 at 06:33:23PM +0200, Jason A. Donenfeld wrote: > > > On Mon, Jun 17, 2024 at 6:30 PM Uladzislau Rezki <urezki@xxxxxxxxx> wrote: > > > > Here if an "err" is less then "0" means there are still objects > > > > whereas "is_destroyed" is set to "true" which is not correlated > > > > with a comment: > > > > > > > > "Destruction happens when no objects" > > > > > > The comment is just poorly written. But the logic of the code is right. > > > > > OK. > > > > > > > > > > > out_unlock: > > > > > mutex_unlock(&slab_mutex); > > > > > cpus_read_unlock(); > > > > > diff --git a/mm/slub.c b/mm/slub.c > > > > > index 1373ac365a46..7db8fe90a323 100644 > > > > > --- a/mm/slub.c > > > > > +++ b/mm/slub.c > > > > > @@ -4510,6 +4510,8 @@ void kmem_cache_free(struct kmem_cache *s, void *x) > > > > > return; > > > > > trace_kmem_cache_free(_RET_IP_, x, s); > > > > > slab_free(s, virt_to_slab(x), x, _RET_IP_); > > > > > + if (s->is_destroyed) > > > > > + kmem_cache_destroy(s); > > > > > Here i am not follow you. How do you see that a cache has been fully > > freed? Or is it just super draft code? > > kmem_cache_destroy() does this in shutdown_cache(). > Right. In this scenario you invoke kmem_cache_destroy() over and over until the last object gets freed. This potentially slowing the kmem_cache_free() which is not OK, at least to me. -- Uladzislau Rezki
