Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753907AbcD0LQB (ORCPT ); Wed, 27 Apr 2016 07:16:01 -0400 Received: from mail-wm0-f66.google.com ([74.125.82.66]:34206 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752290AbcD0LP7 (ORCPT ); Wed, 27 Apr 2016 07:15:59 -0400 Date: Wed, 27 Apr 2016 13:15:56 +0200 From: Michal Hocko To: Tetsuo Handa Cc: linux-mm@kvack.org, Andrew Morton , Dave Chinner , "Theodore Ts'o" , Chris Mason , Jan Kara , LKML Subject: Re: [PATCH 1/2] mm: add PF_MEMALLOC_NOFS Message-ID: <20160427111555.GJ2179@dhcp22.suse.cz> References: <1461671772-1269-1-git-send-email-mhocko@kernel.org> <1461671772-1269-2-git-send-email-mhocko@kernel.org> <32e220de-6028-a32c-e6a5-6935b97d277d@I-love.SAKURA.ne.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <32e220de-6028-a32c-e6a5-6935b97d277d@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 Content-Length: 667 Lines: 17 On Wed 27-04-16 19:53:21, Tetsuo Handa wrote: [...] > > Let's hope that filesystems will drop direct GFP_NOFS (resp. ~__GFP_FS) > > usage as much and possible and only use a properly documented > > memalloc_nofs_{save,restore} checkpoints where they are appropriate. > > Is the story simple enough to monotonically replace GFP_NOFS/GFP_NOIO > with GFP_KERNEL after memalloc_no{fs,io}_{save,restore} are inserted? > We sometimes delegate some operations to somebody else. Don't we need to > convey PF_MEMALLOC_NOFS/PF_MEMALLOC_NOIO flags to APIs which interact with > other threads? We can add an api to do that if that is really needed. -- Michal Hocko SUSE Labs