From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753617AbZBHT3p (ORCPT ); Sun, 8 Feb 2009 14:29:45 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752805AbZBHT3g (ORCPT ); Sun, 8 Feb 2009 14:29:36 -0500 Received: from x35.xmailserver.org ([64.71.152.41]:45043 "EHLO x35.xmailserver.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752773AbZBHT3f (ORCPT ); Sun, 8 Feb 2009 14:29:35 -0500 X-AuthUser: davidel@xmailserver.org Date: Sun, 8 Feb 2009 11:29:33 -0800 (PST) From: Davide Libenzi X-X-Sender: davide@alien.or.mcafeemobile.com To: Michael Kerrisk cc: "linux-man@vger.kernel.org" , lkml , Thomas Gleixner Subject: Re: Why does timerfd() only support CLOCK_REALTIME and CLOCK_MONOTONIC? In-Reply-To: Message-ID: References: User-Agent: Alpine 1.10 (DEB 962 2008-03-14) X-GPG-FINGRPRINT: CFAE 5BEE FD36 F65E E640 56FE 0974 BF23 270F 474E X-GPG-PUBLIC_KEY: http://www.xmailserver.org/davidel.asc MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 9 Feb 2009, Michael Kerrisk wrote: > Hi Davide, > > At the moment I'm looking into writing man pages for timer_create(2) > and friends. (Somewhat bizarrely, these pages do not yet exist.) As > I looked into the source code of timer_create(), etc., and did some > tests, I saw that timer_create() supports the following clocks: > > TIMER_REALTIME > TIMER_MONOTONIC > TIMER_PROCESS_CPUTIME_ID > TIMER_THREAD_CPUTIME_ID > clockid obtained from clock_getcpuclockid(3) > clockid obtained from pthread_getcpuclockid(3) > > On the other hand, timerfd() only permits the first two of these. > What's the reason for that limitation of timerfd()? (It may be worth > adding something to the man page on this point.) No particular reason I can think of. If Thomas makes invalid_clockid() available, we could allow timerfd() to support all time timers timer_create() supports. Do you see any reason why this won't work Thomas? - Davide