From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wj0-f199.google.com (mail-wj0-f199.google.com [209.85.210.199]) by kanga.kvack.org (Postfix) with ESMTP id 09DCC6B025E for ; Mon, 12 Dec 2016 03:52:58 -0500 (EST) Received: by mail-wj0-f199.google.com with SMTP id xy5so22243634wjc.0 for ; Mon, 12 Dec 2016 00:52:57 -0800 (PST) Received: from mail-wj0-f193.google.com (mail-wj0-f193.google.com. [209.85.210.193]) by mx.google.com with ESMTPS id v186si27462560wma.24.2016.12.12.00.52.56 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 12 Dec 2016 00:52:56 -0800 (PST) Received: by mail-wj0-f193.google.com with SMTP id xy5so10256912wjc.1 for ; Mon, 12 Dec 2016 00:52:56 -0800 (PST) Date: Mon, 12 Dec 2016 09:52:55 +0100 From: Michal Hocko Subject: Re: [PATCH 2/2] mm, oom: do not enfore OOM killer for __GFP_NOFAIL automatically Message-ID: <20161212085254.GC18163@dhcp22.suse.cz> References: <201612061938.DDD73970.QFHOFJStFOLVOM@I-love.SAKURA.ne.jp> <20161206192242.GA10273@dhcp22.suse.cz> <201612082153.BHC81241.VtMFFHOLJOOFSQ@I-love.SAKURA.ne.jp> <20161208134718.GC26530@dhcp22.suse.cz> <201612112023.HBB57332.QOFFtJLOOMFSVH@I-love.SAKURA.ne.jp> <201612112253.GGH60933.tOMHJQOFSOFFVL@I-love.SAKURA.ne.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201612112253.GGH60933.tOMHJQOFSOFFVL@I-love.SAKURA.ne.jp> Sender: owner-linux-mm@kvack.org List-ID: To: Tetsuo Handa Cc: akpm@linux-foundation.org, vbabka@suse.cz, hannes@cmpxchg.org, mgorman@suse.de, rientjes@google.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org On Sun 11-12-16 22:53:55, Tetsuo Handa wrote: > Tetsuo Handa wrote: > > Michal Hocko wrote: > > > On Thu 08-12-16 21:53:44, Tetsuo Handa wrote: > > > > If we could agree > > > > with calling __alloc_pages_nowmark() before out_of_memory() if __GFP_NOFAIL > > > > is given, we can avoid locking up while minimizing possibility of invoking > > > > the OOM killer... > > > > > > I do not understand. We do __alloc_pages_nowmark even when oom is called > > > for GFP_NOFAIL. > > > > Where is that? I can find __alloc_pages_nowmark() after out_of_memory() > > if __GFP_NOFAIL is given, but I can't find __alloc_pages_nowmark() before > > out_of_memory() if __GFP_NOFAIL is given. > > > > What I mean is below patch folded into > > "[PATCH 1/2] mm: consolidate GFP_NOFAIL checks in the allocator slowpath". > > > Oops, I wrongly implemented "__alloc_pages_nowmark() before out_of_memory() if > __GFP_NOFAIL is given." case. Updated version is shown below. If you want to introduce such a change then make sure to justify it properly in the changelog. I will not comment on this change here because I believe it is not directly needed for neither of the two patches. -- Michal Hocko SUSE Labs -- 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