From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758112AbbJVWrL (ORCPT ); Thu, 22 Oct 2015 18:47:11 -0400 Received: from mail-pa0-f41.google.com ([209.85.220.41]:33548 "EHLO mail-pa0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756487AbbJVWrK (ORCPT ); Thu, 22 Oct 2015 18:47:10 -0400 Date: Fri, 23 Oct 2015 07:47:01 +0900 From: Tejun Heo To: Tetsuo Handa Cc: mhocko@kernel.org, cl@linux.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, rientjes@google.com, oleg@redhat.com, kwalker@redhat.com, akpm@linux-foundation.org, hannes@cmpxchg.org, vdavydov@parallels.com, skozina@redhat.com, mgorman@suse.de, riel@redhat.com Subject: Re: [PATCH] mm,vmscan: Use accurate values for zone_reclaimable()checks Message-ID: <20151022224701.GA5442@mtj.duckdns.org> References: <20151022151528.GG30579@mtj.duckdns.org> <20151022153559.GF26854@dhcp22.suse.cz> <20151022153703.GA3899@mtj.duckdns.org> <20151022154922.GG26854@dhcp22.suse.cz> <20151022184226.GA19289@mtj.duckdns.org> <201510230642.HDF57807.QJtSOVFFOMLHOF@I-love.SAKURA.ne.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201510230642.HDF57807.QJtSOVFFOMLHOF@I-love.SAKURA.ne.jp> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Fri, Oct 23, 2015 at 06:42:43AM +0900, Tetsuo Handa wrote: > Then, isn't below change easier to backport which will also alleviate > needlessly burning CPU cycles? > > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -3385,6 +3385,7 @@ retry: > ((gfp_mask & __GFP_REPEAT) && pages_reclaimed < (1 << order))) { > /* Wait for some write requests to complete then retry */ > wait_iff_congested(ac->preferred_zone, BLK_RW_ASYNC, HZ/50); > + schedule_timeout_uninterruptible(1); > goto retry; > } Yeah, that works too. It should still be put on a dedicated wq with MEM_RECLAIM tho. Thanks. -- tejun