Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752949Ab1DZJ2F (ORCPT ); Tue, 26 Apr 2011 05:28:05 -0400 Received: from mail-wy0-f174.google.com ([74.125.82.174]:48330 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752596Ab1DZJ2D convert rfc822-to-8bit (ORCPT ); Tue, 26 Apr 2011 05:28:03 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=WIoNVZc/k1SXaH0bW4mcCOrZ1ZHOJjPxY98v99M8LTnRmB2LCrBVlBuJLojD+RhwTm OHicrbvK7u+AxhQ690PK94tv0INhEM4QJ49Rfr4OP5dK2DlGRb1hPnyc8LAy7FeXe3VP FOHTfX+/2giJwdal1/BNV4Nr0I6fKPdIoSdD0= MIME-Version: 1.0 In-Reply-To: <20110426085953.GA12389@darkstar> References: <20110426085953.GA12389@darkstar> Date: Tue, 26 Apr 2011 18:28:01 +0900 Message-ID: Subject: Re: [PATCH v2] virtio_balloon: disable oom killer when fill balloon From: Minchan Kim To: Dave Young Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, kosaki.motohiro@jp.fujitsu.com, linux-mm Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1971 Lines: 54 Please resend this with [2/2] to linux-mm. On Tue, Apr 26, 2011 at 5:59 PM, Dave Young wrote: > When memory pressure is high, virtio ballooning will probably cause oom killing. > Even if alloc_page with GFP_NORETRY itself does not directly trigger oom it > will make memory becoming low then memory alloc of other processes will trigger > oom killing. It is not desired behaviour. I can't understand why it is undesirable. Why do we have to handle it specially? > > Here disable oom killer in fill_balloon to address this issue. > Add code comment as KOSAKI Motohiro's suggestion. > > Signed-off-by: Dave Young > --- >  drivers/virtio/virtio_balloon.c |    8 ++++++++ >  1 file changed, 8 insertions(+) > > --- linux-2.6.orig/drivers/virtio/virtio_balloon.c      2011-04-26 11:39:14.053118406 +0800 > +++ linux-2.6/drivers/virtio/virtio_balloon.c   2011-04-26 16:54:56.419741542 +0800 > @@ -25,6 +25,7 @@ >  #include >  #include >  #include > +#include > >  struct virtio_balloon >  { > @@ -102,6 +103,12 @@ static void fill_balloon(struct virtio_b >        /* We can only do one array worth at a time. */ >        num = min(num, ARRAY_SIZE(vb->pfns)); > > +       /* Disable oom killer for indirect oom due to our memory consuming > +        * Currently only hibernation code use oom_killer_disable, Hmm, Please look at current mmotm. Now oom_killer_disabled is used by do_try_to_free_pages in mmotm so it could make unnecessary oom kill. BTW, I can't understand why we need to handle virtio by special. Could you explain it in detail? :) -- Kind regards, Minchan Kim -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/