From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with ESMTP id C577A6006B4 for ; Mon, 19 Jul 2010 17:36:14 -0400 (EDT) Date: Mon, 19 Jul 2010 14:35:20 -0700 From: Andrew Morton Subject: Re: [PATCH 3/6] writeback: avoid unnecessary calculation of bdi dirty thresholds Message-Id: <20100719143520.d9af9649.akpm@linux-foundation.org> In-Reply-To: <20100711021748.879183413@intel.com> References: <20100711020656.340075560@intel.com> <20100711021748.879183413@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Wu Fengguang Cc: Christoph Hellwig , Peter Zijlstra , Dave Chinner , Jan Kara , linux-fsdevel@vger.kernel.org, Linux Memory Management List , LKML List-ID: On Sun, 11 Jul 2010 10:06:59 +0800 Wu Fengguang wrote: > Split get_dirty_limits() into global_dirty_limits()+bdi_dirty_limit(), > so that the latter can be avoided when under global dirty background > threshold (which is the normal state for most systems). > mm/page-writeback.c: In function 'balance_dirty_pages_ratelimited_nr': mm/page-writeback.c:466: warning: 'dirty_exceeded' may be used uninitialized in this function This was a real bug. --- a/mm/page-writeback.c~writeback-avoid-unnecessary-calculation-of-bdi-dirty-thresholds-fix +++ a/mm/page-writeback.c @@ -463,7 +463,7 @@ static void balance_dirty_pages(struct a unsigned long bdi_thresh; unsigned long pages_written = 0; unsigned long pause = 1; - int dirty_exceeded; + bool dirty_exceeded = false; struct backing_dev_info *bdi = mapping->backing_dev_info; for (;;) { _ -- 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