From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264067AbTGOG5R (ORCPT ); Tue, 15 Jul 2003 02:57:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264085AbTGOG5R (ORCPT ); Tue, 15 Jul 2003 02:57:17 -0400 Received: from [66.212.224.118] ([66.212.224.118]:7950 "EHLO hemi.commfireservices.com") by vger.kernel.org with ESMTP id S264067AbTGOG5Q (ORCPT ); Tue, 15 Jul 2003 02:57:16 -0400 Date: Tue, 15 Jul 2003 03:00:43 -0400 (EDT) From: Zwane Mwaikambo X-X-Sender: zwane@montezuma.mastecende.com To: Andrew Morton Cc: Con Kolivas , linux-kernel@vger.kernel.org, efault@gmx.de, felipe_alfaro@linuxmail.org Subject: Re: [PATCH] N1int for interactivity In-Reply-To: <20030714205915.5a4c8d16.akpm@osdl.org> Message-ID: References: <200307151355.23586.kernel@kolivas.org> <20030714205915.5a4c8d16.akpm@osdl.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 14 Jul 2003, Andrew Morton wrote: > > base = monotonic_base; > > - read_unlock_irq(&monotonic_lock); > > + read_unlock_irqrestore(&monotonic_lock, flags); > > > > /* Read the Time Stamp Counter */ > > Why do we need to take a global lock here? Can't we use > get_cycles() or something? I think that'll break even on some x86 boxes if we used get_cycles. I do wonder however why we need that lock, i see x86/64 uses seqlock at least. Although i can't vouch for whether that would have an adverse affect here. I presume Stultz would know. > Have all the other architectures been reviewed to see if they need this > change? No one else appears to have monotonic_clock, this would break every other arch out there. -- function.linuxpower.ca