From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 8 Jul 2002 08:26:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 8 Jul 2002 08:26:51 -0400 Received: from parcelfarce.linux.theplanet.co.uk ([195.92.249.252]:5132 "EHLO www.linux.org.uk") by vger.kernel.org with ESMTP id ; Mon, 8 Jul 2002 08:26:50 -0400 Date: Mon, 8 Jul 2002 13:29:30 +0100 From: Matthew Wilcox To: Dave Hansen Cc: Matthew Wilcox , Oliver Neukum , Thunder from the hill , Greg KH , kernel-janitor-discuss , linux-kernel@vger.kernel.org Subject: Re: BKL removal Message-ID: <20020708132930.R27706@parcelfarce.linux.theplanet.co.uk> References: <200207080131.06119.oliver@neukum.name> <3D28D291.3020706@us.ibm.com> <20020708033409.P27706@parcelfarce.linux.theplanet.co.uk> <3D28FE72.1080603@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <3D28FE72.1080603@us.ibm.com>; from haveblue@us.ibm.com on Sun, Jul 07, 2002 at 07:52:34PM -0700 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Jul 07, 2002 at 07:52:34PM -0700, Dave Hansen wrote: > Well, I certainly have the hardware to measure the difference. But, I > seem to remember several conversations in the past where people didn't > like this behavior. > http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&safe=off&threadm=linux.kernel.3C62DABA.3020906%40us.ibm.com I think this is a very different philosophy. That's "well, this should be a spinlock, but sometimes we sleep, and we don't want to think about it too hard, so let's invent a magical lock". This is "sometimes we don't hold semaphores for very long so we can improve performance by spinning 1000 times before sleeping". -- Revolutions do not require corporate support.