Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262176AbVCOAsN (ORCPT ); Mon, 14 Mar 2005 19:48:13 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262175AbVCOApH (ORCPT ); Mon, 14 Mar 2005 19:45:07 -0500 Received: from omx2-ext.sgi.com ([192.48.171.19]:206 "EHLO omx2.sgi.com") by vger.kernel.org with ESMTP id S262143AbVCOAHX (ORCPT ); Mon, 14 Mar 2005 19:07:23 -0500 Date: Mon, 14 Mar 2005 16:01:34 -0800 (PST) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Matt Mackall cc: john stultz , lkml , Tim Schmielau , George Anzinger , albert@users.sourceforge.net, Ulrich Windl , Dominik Brodowski , David Mosberger , Andi Kleen , paulus@samba.org, schwidefsky@de.ibm.com, keith maanthey , Patricia Gaughen , Chris McDermott , Max Asbock , mahuja@us.ibm.com, Nishanth Aravamudan , Darren Hart , "Darrick J. Wong" , Anton Blanchard , donf@us.ibm.com Subject: Re: [RFC][PATCH] new timeofday core subsystem (v. A3) In-Reply-To: <20050314202702.GF32638@waste.org> Message-ID: References: <1110590655.30498.327.camel@cog.beaverton.ibm.com> <20050313004902.GD3163@waste.org> <1110825765.30498.370.camel@cog.beaverton.ibm.com> <20050314192918.GC32638@waste.org> <1110829401.30498.383.camel@cog.beaverton.ibm.com> <20050314195110.GD32638@waste.org> <1110830647.30498.388.camel@cog.beaverton.ibm.com> <20050314202702.GF32638@waste.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 Content-Length: 845 Lines: 16 On Mon, 14 Mar 2005, Matt Mackall wrote: > We can either stick all the generic mmio timer functions in the > vsyscall page (they're tiny) or leave the vsyscall using type/ptr but > have the kernel internally use only the function pointer. Someone > who's more familiar with the vsyscall timer code should chime in here. No we cannot do any function calls in a fastcall path on ia64. The current design is ok. Why duplicate the functionality with additional indirect function calls? Plus an indirect function calls stalls pipelines on some processors and will limit the performance of gettimeofday. - 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/