From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S269352AbUIYPTp (ORCPT ); Sat, 25 Sep 2004 11:19:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S269353AbUIYPTp (ORCPT ); Sat, 25 Sep 2004 11:19:45 -0400 Received: from mx1.redhat.com ([66.187.233.31]:60584 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S269352AbUIYPTn (ORCPT ); Sat, 25 Sep 2004 11:19:43 -0400 Message-ID: <41558C6D.4050305@redhat.com> Date: Sat, 25 Sep 2004 08:19:09 -0700 From: Ulrich Drepper Organization: Red Hat, Inc. User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8a4) Gecko/20040923 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Christoph Lameter CC: linux-kernel@vger.kernel.org Subject: Re: [time] add support for CLOCK_THREAD_CPUTIME_ID and CLOCK_PROCESS_CPUTIME_ID References: <4154F349.1090408@redhat.com> <41550B77.1070604@redhat.com> In-Reply-To: X-Enigmail-Version: 0.86.0.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Christoph Lameter wrote: > Yes and glibc will have to get through contortions to > simulate a clock that returns the actual cpu time used. Why not cleanly > do the clock_gettime syscall without doing any redirection of clocks? First of all, unnecessary kernel code where it is not needed. And second, because with the definition of the CPUTIME clock in use for many years now not all variants can be handled in the kernel. We use this clock to provide access to the TSC functionality. This is nothing the kernel does. > Any implementation of the CPUTIME clocks is always easier to do in the > kernel with just a few lines. No, you don't know the glibc side. > Ok, I will dig out my old patch and repost it to glibc-alpha. I haven't gotten an answer to the question "is there really any value in this kind of clock?". - -- ➧ Ulrich Drepper ➧ Red Hat, Inc. ➧ 444 Castro St ➧ Mountain View, CA ❖ -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.6 (GNU/Linux) iD8DBQFBVYxt2ijCOnn/RHQRAmohAKCVAlRAxIHBi5uHqoKtfjfORQQNiACdHPuD aCn2+pHl7MnBmWE2CAmSdb8= =vJAO -----END PGP SIGNATURE-----