From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261485AbVGNQLY (ORCPT ); Thu, 14 Jul 2005 12:11:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263053AbVGNQJG (ORCPT ); Thu, 14 Jul 2005 12:09:06 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:43457 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S263046AbVGNQIs (ORCPT ); Thu, 14 Jul 2005 12:08:48 -0400 Date: Thu, 14 Jul 2005 17:08:38 +0100 From: Christoph Hellwig To: Daniel Walker Cc: Ingo Molnar , Dave Chinner , greg@kroah.com, Nathan Scott , Steve Lord , linux-kernel@vger.kernel.org, linux-xfs@oss.sgi.com Subject: Re: RT and XFS Message-ID: <20050714160838.GB19229@infradead.org> Mail-Followup-To: Christoph Hellwig , Daniel Walker , Ingo Molnar , Dave Chinner , greg@kroah.com, Nathan Scott , Steve Lord , linux-kernel@vger.kernel.org, linux-xfs@oss.sgi.com References: <1121209293.26644.8.camel@dhcp153.mvista.com> <20050713002556.GA980@frodo> <20050713064739.GD12661@elte.hu> <1121273158.13259.9.camel@c-67-188-6-232.hsd1.ca.comcast.net> <20050714002246.GA937@frodo> <20050714135023.E241419@melbourne.sgi.com> <1121314226.14816.18.camel@c-67-188-6-232.hsd1.ca.comcast.net> <20050714052347.GA18813@elte.hu> <1121356618.14816.45.camel@c-67-188-6-232.hsd1.ca.comcast.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1121356618.14816.45.camel@c-67-188-6-232.hsd1.ca.comcast.net> User-Agent: Mutt/1.4.2.1i X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 14, 2005 at 08:56:58AM -0700, Daniel Walker wrote: > On Thu, 2005-07-14 at 07:23 +0200, Ingo Molnar wrote: > > * Daniel Walker wrote: > > > > > > The whole point of using a semaphore in the pagebuf is because there > > > > is no tracking of who "owns" the lock so we can actually release it > > > > in a different context. Semaphores were invented for this purpose, > > > > and we use them in the way they were intended. ;) > > > > > > Where is the that semaphore spec, is that posix ? There is a new > > > construct called "complete" that is good for this type of stuff too. > > > No owner needed , just something running, and something waiting till > > > it completes. > > > > wrt. posix, we dont really care about that for kernel-internal > > primitives like struct semaphore. So whether it's posix or not has no > > relevance. > > This reminds me of Documentation/stable_api_nonsense.txt . That no one > should really be dependent on a particular kernel API doing a particular > thing. The kernel is play dough for the kernel hacker (as it should be), > including kernel semaphores. > > So we can change whatever we want, and make no excuses, as long as we > fix the rest of the kernel to work with our change. That seems pretty > sensible , because Linux should be an evolution. > > Daniel > > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ ---end quoted text---