From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753268Ab1GUQaY (ORCPT ); Thu, 21 Jul 2011 12:30:24 -0400 Received: from cantor2.suse.de ([195.135.220.15]:50851 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753195Ab1GUQ3G (ORCPT ); Thu, 21 Jul 2011 12:29:06 -0400 From: Mel Gorman To: Linux-MM Cc: LKML , XFS , Dave Chinner , Christoph Hellwig , Johannes Weiner , Wu Fengguang , Jan Kara , Rik van Riel , Minchan Kim , Mel Gorman Subject: [PATCH 3/8] ext4: Warn if direct reclaim tries to writeback pages Date: Thu, 21 Jul 2011 17:28:45 +0100 Message-Id: <1311265730-5324-4-git-send-email-mgorman@suse.de> X-Mailer: git-send-email 1.7.3.4 In-Reply-To: <1311265730-5324-1-git-send-email-mgorman@suse.de> References: <1311265730-5324-1-git-send-email-mgorman@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Direct reclaim should never writeback pages. Warn if an attempt is made. Signed-off-by: Mel Gorman --- fs/ext4/inode.c | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index e3126c0..95bb179 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -2663,8 +2663,12 @@ static int ext4_writepage(struct page *page, * We don't want to do block allocation, so redirty * the page and return. We may reach here when we do * a journal commit via journal_submit_inode_data_buffers. - * We can also reach here via shrink_page_list + * We can also reach here via shrink_page_list but it + * should never be for direct reclaim so warn if that + * happens */ + WARN_ON_ONCE((current->flags & (PF_MEMALLOC|PF_KSWAPD)) == + PF_MEMALLOC); goto redirty_page; } if (commit_write) -- 1.7.3.4