From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 17 Dec 2002 13:50:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 17 Dec 2002 13:50:38 -0500 Received: from cpe-24-221-190-179.ca.sprintbbd.net ([24.221.190.179]:55476 "EHLO myware.akkadia.org") by vger.kernel.org with ESMTP id ; Tue, 17 Dec 2002 13:50:37 -0500 Message-ID: <3DFF7399.40708@redhat.com> Date: Tue, 17 Dec 2002 10:57:29 -0800 From: Ulrich Drepper Organization: Red Hat, Inc. User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.3b) Gecko/20021216 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Alan Cox CC: Linus Torvalds , Matti Aarnio , Hugh Dickins , Dave Jones , Ingo Molnar , Linux Kernel Mailing List , hpa@transmeta.com Subject: Re: Intel P6 vs P7 system call performance References: <3DFF6D4B.3060107@redhat.com> <1040153186.20780.11.camel@irongate.swansea.linux.org.uk> In-Reply-To: <1040153186.20780.11.camel@irongate.swansea.linux.org.uk> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Alan Cox wrote: > getppid changes and so I think has to go to kernel (unless we go around > patching user pages on process exit [ick]). But this is exactly what I expect to happen. If you want to implement gettimeofday() at user-level you need to modify the page. Some of the information the kernel has to keep for the thread group can be stored in this place and eventually be used by some uerlevel code executed by jumping to 0xfffff000 or whatever the address is. -- --------------. ,-. 444 Castro Street Ulrich Drepper \ ,-----------------' \ Mountain View, CA 94041 USA Red Hat `--' drepper at redhat.com `---------------------------