From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932286AbXDLObl (ORCPT ); Thu, 12 Apr 2007 10:31:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932290AbXDLObl (ORCPT ); Thu, 12 Apr 2007 10:31:41 -0400 Received: from kanga.kvack.org ([66.96.29.28]:56095 "EHLO kanga.kvack.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932286AbXDLObk (ORCPT ); Thu, 12 Apr 2007 10:31:40 -0400 Date: Thu, 12 Apr 2007 10:31:31 -0400 From: Benjamin LaHaise To: Ken Chen Cc: Zach Brown , akpm@linux-foundation.org, linux-aio@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [patch] convert aio event reap to use atomic-op instead of spin_lock Message-ID: <20070412143131.GP13621@kvack.org> References: <20070410235353.325A7346F64@localhost> <20070411180038.GN28322@mami.zabbo.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 12, 2007 at 12:50:39AM -0700, Ken Chen wrote: > I ran through the autotest (with bug fix in the test code). It passes > the regression tests. I made the following change since last rev: By removing the spinlock around ring insertion, you've made it possible for two events being inserted on different CPUs to end up creating inconsistent state, as there is nothing which guarantees that resulting event in the ring will be wholely one event or another. Also, I don't like rounding up of the number of events to the nearest power of two, as it can round things up significantly more than just going to the end of the last actual page of memory allocated. NAK. -ben PS base64 encoded patches are incredibly difficult to quote. -- "Time is of no importance, Mr. President, only life is important." Don't Email: .