From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030895AbXCNUe1 (ORCPT ); Wed, 14 Mar 2007 16:34:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030887AbXCNUe1 (ORCPT ); Wed, 14 Mar 2007 16:34:27 -0400 Received: from smtp-outbound-1.vmware.com ([65.113.40.141]:53205 "EHLO smtp-outbound-1.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030892AbXCNUeZ (ORCPT ); Wed, 14 Mar 2007 16:34:25 -0400 Message-ID: <45F85C4F.10704@vmware.com> Date: Wed, 14 Mar 2007 12:34:23 -0800 From: Zachary Amsden User-Agent: Thunderbird 1.5.0.10 (X11/20070221) MIME-Version: 1.0 To: Jeremy Fitzhardinge CC: Dan Hecht , Virtualization Mailing List , Linux Kernel Mailing List , john stultz Subject: Re: [PATCH/RFC] replace get_scheduled_cycles with sched_clock paravirt_op References: <45F847E2.7040102@goop.org> In-Reply-To: <45F847E2.7040102@goop.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Jeremy Fitzhardinge wrote: > Subject: Add a sched_clock paravirt_op > > The tsc-based get_scheduled_cycles interface is not a good match for > Xen's runstate accounting, which reports everything in nanoseconds. > > This patch replaces this interface with a sched_clock interface, which > matches both Xen and VMI's requirements. > > In order to do this, we: > 1. replace get_scheduled_cycles with sched_clock > 2. hoist cycles_2_ns into a common header > 3. update vmi accordingly > > One thing to note: because sched_clock is implemented as a weak function in > kernel/sched.c, we must define a real function in order to override this weak > binding. This means the usual paravirt_ops technique of using an inline > function won't work in this case. > Acked-by: Zachary Amsden