From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757470Ab0EUOyA (ORCPT ); Fri, 21 May 2010 10:54:00 -0400 Received: from relay.parallels.com ([195.214.232.42]:41430 "EHLO relay.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755325Ab0EUOx6 (ORCPT ); Fri, 21 May 2010 10:53:58 -0400 Message-ID: <4BF69E82.4060904@parallels.com> Date: Fri, 21 May 2010 18:53:54 +0400 From: Konstantin Khlebnikov User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.9) Gecko/20100423 Thunderbird/3.0.4 MIME-Version: 1.0 To: Jens Axboe CC: "linux-kernel@vger.kernel.org" , Dmitry Monakhov Subject: Re: [PATCH 1/2] cfq-iosched: remove dead_key from cfq_io_context References: <20100520192134.19366.88949.stgit@zurg> <20100521094047.GB11217@kernel.dk> In-Reply-To: <20100521094047.GB11217@kernel.dk> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 21.05.2010 13:40, Jens Axboe wrote: > On Thu, May 20 2010, Konstantin Khlebnikov wrote: >> Remove ->dead_key field from cfq_io_context to shrink its size to 128 bytes. >> (64 bytes for 32-bit hosts) >> >> Use lower bit in ->key as dead-mark, instead of moving key to separate field. >> After this for dead cfq_io_context we got cic->key != cfqd automatically. >> Thus, io_context's last-hit cache should work without changing. >> >> Now to check ->key for non-dead state compare it with cfqd, >> instead of checking ->key for non-null value as it was before. >> >> Plus remove obsolete race protection in cfq_cic_lookup. >> This race gone after v2.6.24-1728-g4ac845a > > This, and the second patch, look really good. How much testing have you > done with it? > I have run multiple fsstress and simultaneously switch io-scheduler in loop for several hours, no oopses and leaks detected.