Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752369Ab1DZItK (ORCPT ); Tue, 26 Apr 2011 04:49:10 -0400 Received: from mail-pz0-f46.google.com ([209.85.210.46]:48353 "EHLO mail-pz0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752081Ab1DZItJ (ORCPT ); Tue, 26 Apr 2011 04:49:09 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:subject:message-id:mime-version:content-type :content-disposition:user-agent; b=RvGy6zHOv75bOYfLW2FRst0+l1KK0YkPADn9qg/VyyQ8ATSnviM6byvJPs4kx/xBiI doHD4ySq4DE+PYhRmTdITfO92hpnOeP6v+bxgi5OUtLkyJb0kEK709T77TvEbHFSUhwy XpHZJ5EWqWaYuiLsq+zslC9WFt3preRcRCKFA= Date: Tue, 26 Apr 2011 16:59:53 +0800 From: Dave Young To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, kosaki.motohiro@jp.fujitsu.com Subject: [PATCH v2] virtio_balloon: disable oom killer when fill balloon Message-ID: <20110426085953.GA12389@darkstar> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1883 Lines: 49 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. 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, + * hibernation will freeze us before disable oom killer, so + * It's safe here without locks. + */ + oom_killer_disable(); for (vb->num_pfns = 0; vb->num_pfns < num; vb->num_pfns++) { struct page *page = alloc_page(GFP_HIGHUSER | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN); @@ -119,6 +126,7 @@ static void fill_balloon(struct virtio_b vb->num_pages++; list_add(&page->lru, &vb->pages); } + oom_killer_enable(); /* Didn't get any? Oh well. */ if (vb->num_pfns == 0) -- 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/