From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx169.postini.com [74.125.245.169]) by kanga.kvack.org (Postfix) with SMTP id 838C26B005D for ; Thu, 16 Aug 2012 03:06:54 -0400 (EDT) Received: by lahd3 with SMTP id d3so1513355lah.14 for ; Thu, 16 Aug 2012 00:06:52 -0700 (PDT) Date: Thu, 16 Aug 2012 10:06:50 +0300 (EEST) From: Pekka Enberg Subject: Re: [PATCH 2/3] slub: reduce failure of this_cpu_cmpxchg in put_cpu_partial() after unfreezing In-Reply-To: <1340389359-2407-2-git-send-email-js1304@gmail.com> Message-ID: References: <1340389359-2407-1-git-send-email-js1304@gmail.com> <1340389359-2407-2-git-send-email-js1304@gmail.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Joonsoo Kim Cc: Christoph Lameter , linux-kernel@vger.kernel.org, linux-mm@kvack.org On Sat, 23 Jun 2012, Joonsoo Kim wrote: > In current implementation, after unfreezing, we doesn't touch oldpage, > so it remain 'NOT NULL'. When we call this_cpu_cmpxchg() > with this old oldpage, this_cpu_cmpxchg() is mostly be failed. > > We can change value of oldpage to NULL after unfreezing, > because unfreeze_partial() ensure that all the cpu partial slabs is removed > from cpu partial list. In this time, we could expect that > this_cpu_cmpxchg is mostly succeed. > > Signed-off-by: Joonsoo Kim > > diff --git a/mm/slub.c b/mm/slub.c > index 92f1c0e..531d8ed 100644 > --- a/mm/slub.c > +++ b/mm/slub.c > @@ -1968,6 +1968,7 @@ int put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) > local_irq_save(flags); > unfreeze_partials(s); > local_irq_restore(flags); > + oldpage = NULL; > pobjects = 0; > pages = 0; > stat(s, CPU_PARTIAL_DRAIN); Applied, thanks! -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org