From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 15 Jan 2008 21:51:49 -0800 From: Andrew Morton Subject: Re: [patch] Converting writeback linked lists to a tree based data structure Message-Id: <20080115215149.a881efff.akpm@linux-foundation.org> In-Reply-To: <400459376.04290@ustc.edu.cn> References: <20080115080921.70E3810653@localhost> <1200386774.15103.20.camel@twins> <532480950801150953g5a25f041ge1ad4eeb1b9bc04b@mail.gmail.com> <400452490.28636@ustc.edu.cn> <20080115194415.64ba95f2.akpm@linux-foundation.org> <400457571.32162@ustc.edu.cn> <20080115204236.6349ac48.akpm@linux-foundation.org> <400459376.04290@ustc.edu.cn> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Fengguang Wu Cc: Michael Rubin , Peter Zijlstra , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Wed, 16 Jan 2008 12:55:07 +0800 Fengguang Wu wrote: > On Tue, Jan 15, 2008 at 08:42:36PM -0800, Andrew Morton wrote: > > On Wed, 16 Jan 2008 12:25:53 +0800 Fengguang Wu wrote: > > > > > list_heads are OK if we use them for one and only function. > > > > Not really. They're inappropriate when you wish to remember your > > position in the list while you dropped the lock (as we must do in > > writeback). > > > > A data structure which permits us to interate across the search key rather > > than across the actual storage locations is more appropriate. > > I totally agree with you. What I mean is to first do the split of > functions - into three: ordering, starvation prevention, and blockade > waiting. Does "ordering" here refer to ordering bt time-of-first-dirty? What is "blockade waiting"? > Then to do better ordering by adopting radix tree(or rbtree > if radix tree is not enough), ordering of what? > and lastly get rid of the list_heads to > avoid locking. Does it sound like a good path? I'd have thaought that replacing list_heads with another data structure would be a simgle commit. -- 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