From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx184.postini.com [74.125.245.184]) by kanga.kvack.org (Postfix) with SMTP id B982B6B004D for ; Wed, 18 Jan 2012 07:09:15 -0500 (EST) Received: by vbbfa15 with SMTP id fa15so3154738vbb.14 for ; Wed, 18 Jan 2012 04:09:14 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1326265453_1662@mail4.comsite.net> References: <1326040026-7285-6-git-send-email-gilad@benyossef.com> <1326265453_1662@mail4.comsite.net> Date: Wed, 18 Jan 2012 14:09:14 +0200 Message-ID: Subject: Re: [PATCH v6 5/8] slub: only IPI CPUs that have per cpu obj to flush From: Gilad Ben-Yossef Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org List-ID: To: Milton Miller Cc: linux-kernel@vger.kernel.org, Christoph Lameter , Michal Nazarewicz , Mel Gorman , KOSAKI Motohiro , Chris Metcalf , Peter Zijlstra , Frederic Weisbecker , Russell King , linux-mm@kvack.org, Pekka Enberg , Matt Mackall , Rik van Riel , Andi Kleen , Sasha Levin , Andrew Morton , Alexander Viro , linux-fsdevel@vger.kernel.org, Avi Kivity On Wed, Jan 11, 2012 at 9:04 AM, Milton Miller wrote: > > > mm/slub.c | 10 +++++++++- > > 1 files changed, 9 insertions(+), 1 deletions(-) > > > > diff --git a/mm/slub.c b/mm/slub.c > > index 09ccee8..31833d6 100644 > > --- a/mm/slub.c > > +++ b/mm/slub.c > > @@ -2013,9 +2013,17 @@ static void flush_cpu_slab(void *d) > > __flush_cpu_slab(s, smp_processor_id()); > > } > > > > +static int has_cpu_slab(int cpu, void *info) > > +{ > > + struct kmem_cache *s =3D info; > > + struct kmem_cache_cpu *c =3D per_cpu_ptr(s->cpu_slab, cpu); > > + > > + return !!(c->page); > > __flush_cpu_slab is careful to test that the the per_cpu_ptr is not > NULL before referencing the page field. =A0free_percpu likewise ignores > NULL pointers. =A0We need to check !!(c && c->page) here. > This is indeed what I did in the first iterations but Christoph indicated t= hat c could never be NULL in his review of the patch. See : https://lkml.org/lkml/2011/11/15/207 I integrated all the other review comment of this patch though. Thanks! Gilad -- Gilad Ben-Yossef Chief Coffee Drinker gilad@benyossef.com Israel Cell: +972-52-8260388 US Cell: +1-973-8260388 http://benyossef.com "Unfortunately, cache misses are an equal opportunity pain provider." -- Mike Galbraith, LKML -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org