From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with ESMTP id 54ADE6B0082 for ; Tue, 7 Jun 2011 11:14:22 -0400 (EDT) Received: by pwi12 with SMTP id 12so3458222pwi.14 for ; Tue, 07 Jun 2011 08:14:19 -0700 (PDT) Date: Wed, 8 Jun 2011 00:14:12 +0900 From: Minchan Kim Subject: Re: [PATCH 3/4] mm: memory-failure: Fix isolated page count during memory failure Message-ID: <20110607151412.GJ1686@barrios-laptop> References: <1307459225-4481-1-git-send-email-mgorman@suse.de> <1307459225-4481-4-git-send-email-mgorman@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1307459225-4481-4-git-send-email-mgorman@suse.de> Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Andrew Morton , Andrea Arcangeli , Thomas Sattler , Ury Stankevich , Andi Kleen , linux-mm , linux-kernel On Tue, Jun 07, 2011 at 04:07:04PM +0100, Mel Gorman wrote: > From: Minchan Kim > > From: Minchan Kim > > Pages isolated for migration are accounted with the vmstat counters > NR_ISOLATE_[ANON|FILE]. Callers of migrate_pages() are expected to > increment these counters when pages are isolated from the LRU. Once > the pages have been migrated, they are put back on the LRU or freed > and the isolated count is decremented. > > Memory failure is not properly accounting for pages it isolates > causing the NR_ISOLATED counters to be negative. On SMP builds, > this goes unnoticed as negative counters are treated as 0 due to > expected per-cpu drift. On UP builds, the counter is treated by > too_many_isolated() as a large value causing processes to enter D > state during page reclaim or compaction. This patch accounts for > pages isolated by memory failure correctly. > > [mgorman@suse.de: Updated changelog] > Signed-off-by: Minchan Kim > Signed-off-by: Mel Gorman > Reviewed-by: Andrea Arcangeli I was about to resend this patch with your updated description. Thanks! Mel. -- Kind regards Minchan Kim -- 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