From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751661AbdHPMeI (ORCPT ); Wed, 16 Aug 2017 08:34:08 -0400 Received: from mx2.suse.de ([195.135.220.15]:44617 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751287AbdHPMeG (ORCPT ); Wed, 16 Aug 2017 08:34:06 -0400 Date: Wed, 16 Aug 2017 14:33:59 +0200 From: Michal Hocko To: Chen Yu Cc: linux-mm@kvack.org, Andrew Morton , Mel Gorman , Vlastimil Babka , "Rafael J. Wysocki" , Len Brown , Dan Williams , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH][RFC v2] PM / Hibernate: Disable wathdog when creating snapshot Message-ID: <20170816123359.GC32161@dhcp22.suse.cz> References: <1502859218-13099-1-git-send-email-yu.c.chen@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1502859218-13099-1-git-send-email-yu.c.chen@intel.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed 16-08-17 12:53:38, Chen Yu wrote: [...] > @@ -2537,10 +2538,15 @@ void mark_free_pages(struct zone *zone) > unsigned long flags; > unsigned int order, t; > struct page *page; > + bool wd_suspended; > > if (zone_is_empty(zone)) > return; > > + wd_suspended = lockup_detector_suspend() ? false : true; > + if (!wd_suspended) > + pr_warn_once("Failed to disable lockup detector during hibernation.\n"); > + > spin_lock_irqsave(&zone->lock, flags); > > max_zone_pfn = zone_end_pfn(zone); I am not maintainer of this code so I am not very familiar with the full context of this function but lockup_detector_suspend is just too heavy for the purpose you are trying to achive. Really why don't you just poke the watchdog every N pages? -- Michal Hocko SUSE Labs