[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <1322064291.17693.54.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC>
Date: Wed, 23 Nov 2011 17:04:51 +0100
From: Eric Dumazet <eric.dumazet@...il.com>
To: Christoph Lameter <cl@...ux.com>
Cc: Pekka Enberg <penberg@...nel.org>,
Christian Kujau <lists@...dbynature.de>,
Benjamin Herrenschmidt <benh@...nel.crashing.org>,
Markus Trippelsdorf <markus@...ppelsdorf.de>,
"Alex,Shi" <alex.shi@...el.com>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
"linux-mm@...ck.org" <linux-mm@...ck.org>,
Matt Mackall <mpm@...enic.com>,
"netdev@...r.kernel.org" <netdev@...r.kernel.org>,
Tejun Heo <tj@...nel.org>, David Rientjes <rientjes@...gle.com>
Subject: Re: slub: use irqsafe_cpu_cmpxchg for put_cpu_partial
Le mercredi 23 novembre 2011 à 09:14 -0600, Christoph Lameter a écrit :
> I think he only tested the patch that he showed us. Here is the patch
> cleaned up. Do you Want me to feed you the debug fixes patch by patch as
> well?
>
> Subject: slub: use irqsafe_cpu_cmpxchg for put_cpu_partial
>
> The cmpxchg must be irq safe. The fallback for this_cpu_cmpxchg only
> disables preemption which results in per cpu partial page operation
> potentially failing on non x86 platforms.
>
> Signed-off-by: Christoph Lameter <cl@...ux.com>
>
> ---
> mm/slub.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> Index: linux-2.6/mm/slub.c
> ===================================================================
> --- linux-2.6.orig/mm/slub.c 2011-11-23 09:10:48.000000000 -0600
> +++ linux-2.6/mm/slub.c 2011-11-23 09:10:57.000000000 -0600
> @@ -1969,7 +1969,7 @@ int put_cpu_partial(struct kmem_cache *s
> page->pobjects = pobjects;
> page->next = oldpage;
>
> - } while (this_cpu_cmpxchg(s->cpu_slab->partial, oldpage, page) != oldpage);
> + } while (irqsafe_cpu_cmpxchg(s->cpu_slab->partial, oldpage, page) != oldpage);
> stat(s, CPU_PARTIAL_FREE);
> return pobjects;
> }
Acked-by: Eric Dumazet <eric.dumazet@...il.com>
Thanks !
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists