Return-Path: Received: from mail-pf0-f194.google.com ([209.85.192.194]:34269 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752298AbdAFOS5 (ORCPT ); Fri, 6 Jan 2017 09:18:57 -0500 From: Michal Hocko To: , Cc: Andrew Morton , Dave Chinner , djwong@kernel.org, "Theodore Ts'o" , Chris Mason , David Sterba , Jan Kara , ceph-devel@vger.kernel.org, cluster-devel@redhat.com, linux-nfs@vger.kernel.org, logfs@logfs.org, linux-xfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-mtd@lists.infradead.org, reiserfs-devel@vger.kernel.org, linux-ntfs-dev@lists.sourceforge.net, linux-f2fs-devel@lists.sourceforge.net, linux-afs@lists.infradead.org, LKML Subject: [DEBUG PATCH 0/2] debug explicit GFP_NO{FS,IO} usage from the scope context Date: Fri, 6 Jan 2017 15:18:43 +0100 Message-Id: <20170106141845.24362-1-mhocko@kernel.org> In-Reply-To: <20170106141107.23953-1-mhocko@kernel.org> References: <20170106141107.23953-1-mhocko@kernel.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: These two patches should help to identify explicit GFP_NO{FS,IO} usage from withing a scope context and reduce such a usage as a result. Such a usage can be changed to the full GFP_KERNEL because all the calls from within the NO{FS,IO} scope will drop the __GFP_FS resp. __GFP_IO automatically and if the function is called outside of the scope then we do not need to restrict it to NOFS/NOIO as long as all the reclaim recursion unsafe contexts are marked properly. This means that each such a reported allocation site has to be checked before converted. The debugging has to be enabled explicitly by a kernel command line parameter and then it reports the stack trace of the allocation and also the function which has started the current scope. These two patches are _not_ intended to be merged and they are only aimed at debugging.