From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 30 Jan 2003 19:48:39 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 30 Jan 2003 19:48:39 -0500 Received: from [195.223.140.107] ([195.223.140.107]:47489 "EHLO athlon.random") by vger.kernel.org with ESMTP id ; Thu, 30 Jan 2003 19:48:39 -0500 Date: Fri, 31 Jan 2003 01:57:47 +0100 From: Andrea Arcangeli To: Stephen Hemminger , Andrew Morton , Andi Kleen , Linux Kernel Mailing List Subject: Re: frlock and barrier discussion Message-ID: <20030131005746.GA18538@dualathlon.random> References: <1043797341.10150.300.camel@dell_ss3.pdx.osdl.net> <20030128230639.A17385@twiddle.net> <1043889355.10153.571.camel@dell_ss3.pdx.osdl.net> <20030129174133.A19912@twiddle.net> <20030130015219.GT1237@dualathlon.random> <20030130164120.A22148@twiddle.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20030130164120.A22148@twiddle.net> User-Agent: Mutt/1.4i X-GPG-Key: 1024D/68B9CB43 X-PGP-Key: 1024R/CB4660B9 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 30, 2003 at 04:41:20PM -0800, Richard Henderson wrote: > On Thu, Jan 30, 2003 at 02:52:19AM +0100, Andrea Arcangeli wrote: > > you're missing xtimensec is a write. > > Eh? xtimensec is a register. then it's fine, the register will be flushed to ram eventually and it will be within the two wmb(), just write in the example also the line where the xtimensec ""register"" is flushed to ram and it will be in the right place if the register isn't flushed to ram eventually, it will be discared and the whole critical section is a noop from the point of view of the other cpus and no wmb() or rmb() or mb() would be needed in the first place Andrea