From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f72.google.com (mail-pg0-f72.google.com [74.125.83.72]) by kanga.kvack.org (Postfix) with ESMTP id 72D356B02C3 for ; Sun, 4 Jun 2017 15:38:55 -0400 (EDT) Received: by mail-pg0-f72.google.com with SMTP id z6so56351318pgc.13 for ; Sun, 04 Jun 2017 12:38:55 -0700 (PDT) Received: from mail-pf0-x22e.google.com (mail-pf0-x22e.google.com. [2607:f8b0:400e:c00::22e]) by mx.google.com with ESMTPS id i23si5466729pll.379.2017.06.04.12.38.54 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 04 Jun 2017 12:38:54 -0700 (PDT) Received: by mail-pf0-x22e.google.com with SMTP id 9so73233456pfj.1 for ; Sun, 04 Jun 2017 12:38:54 -0700 (PDT) Date: Sun, 4 Jun 2017 12:38:50 -0700 From: Yu Zhao Subject: Re: [PATCH] swap: cond_resched in swap_cgroup_prepare() Message-ID: <20170604193850.GA15369@google.com> References: <20170601195635.20744-1-yuzhao@google.com> <20170602081855.GE29840@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170602081855.GE29840@dhcp22.suse.cz> Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Johannes Weiner , Vladimir Davydov , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org On Fri, Jun 02, 2017 at 10:18:57AM +0200, Michal Hocko wrote: > On Thu 01-06-17 12:56:35, Yu Zhao wrote: > > Saw need_resched() warnings when swapping on large swapfile (TBs) > > because page allocation in swap_cgroup_prepare() took too long. > > Hmm, but the page allocator makes sure to cond_resched for sleeping > allocations. I guess what you mean is something different. It is not the > allocation which took too look but there are too many of them and none > of them sleeps because there is enough memory and the allocator doesn't > sleep in that case. Right? > > > We already cond_resched when freeing page in swap_cgroup_swapoff(). > > Do the same for the page allocation. > > > > Signed-off-by: Yu Zhao > > The patch itself makes sense to me, the changelog could see some > clarification but other than that > Acked-by: Michal Hocko Thanks, I'll clarify the problem in the commit message and resend the patch. -- 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/ . Don't email: email@kvack.org