From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759305AbcLAPZ2 (ORCPT ); Thu, 1 Dec 2016 10:25:28 -0500 Received: from mail-wm0-f65.google.com ([74.125.82.65]:35268 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752054AbcLAPZ1 (ORCPT ); Thu, 1 Dec 2016 10:25:27 -0500 From: Michal Hocko To: Andrew Morton Cc: Vlastimil Babka , Tetsuo Handa , Johannes Weiner , Mel Gorman , David Rientjes , , LKML Subject: [PATCH 0/2] GFP_NOFAIL cleanups Date: Thu, 1 Dec 2016 16:25:15 +0100 Message-Id: <20161201152517.27698-1-mhocko@kernel.org> X-Mailer: git-send-email 2.10.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, I have posted this as an RFC previously [1] as there was no fundamental disagreement I would like to ask for inclusion. Tetsuo has noticed [2] that recent changes have changed GFP_NOFAIL semantic for costly order requests. I believe that the primary reason why this happened is that our GFP_NOFAIL checks are too scattered and it is really easy to forget about adding one. That's why I am proposing patch 1 which consolidates all the nofail handling at a single place. This should help to make this code better maintainable. Patch 2 on top is a further attempt to make GFP_NOFAIL semantic less surprising. As things stand currently GFP_NOFAIL overrides the oom killer prevention code which is both subtle and not really needed. The patch 2 has more details about issues this might cause. I would consider both patches more a cleanup than anything else. Any feedback is highly appreciated. [1] http://lkml.kernel.org/r/20161123064925.9716-1-mhocko@kernel.org [2] http://lkml.kernel.org/r/1479387004-5998-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp