Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753388AbXIDITs (ORCPT ); Tue, 4 Sep 2007 04:19:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752123AbXIDITk (ORCPT ); Tue, 4 Sep 2007 04:19:40 -0400 Received: from smtp2.linux-foundation.org ([207.189.120.14]:35789 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752115AbXIDITj (ORCPT ); Tue, 4 Sep 2007 04:19:39 -0400 Date: Tue, 4 Sep 2007 01:18:00 -0700 From: Andrew Morton To: Michael Kerrisk Cc: davidel@xmailserver.org, rdunlap@xenotime.net, tglx@linutronix.de, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, drepper@redhat.com, stable@kernel.org, hch@lst.de, jengelh@computergmbh.de, corbet@lwn.net Subject: Re: [PATCH] Revised timerfd() interface Message-Id: <20070904011800.762523a4.akpm@linux-foundation.org> In-Reply-To: <46DD116C.4040301@gmx.net> References: <20070825064114.107820@gmx.net> <46DD116C.4040301@gmx.net> X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.19; i686-pc-linux-gnu) Mime-Version: 1.0 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 Content-Length: 1504 Lines: 40 > On Tue, 04 Sep 2007 10:03:56 +0200 Michael Kerrisk wrote: > Davide, > > >> Davide -- ping! Can you please offer your comments about this change, and > >> also thoughts on Jon's and my comments about a more radical API change > >> later in this thread. > > > > IMO the complexity of the resulting API (and resulting patch), and the ABI > > change, is not justified by the added value. > > Neither of the proposed APIs (either my multiplexed version of timerfd() > or Jon's/my idea of using three system calls (like POSIX timers), or > the notion of timerfd() integrated with POSIX timers) is more > complicated than the existing POSIX timers API. > > The ABI change doesn't really matter, since timerfd() was broken in 2.6.22 > anyway. > > Both previous APIs provided the features I have described provide: > > * the ability to fetch the old timer value when applying > a new setting > > * the ability to non-destructively fetch the amount of time remaining > on a timer. > > This is clearly useful for timers -- but you have not explained why > you think this is not necessary for timerfd timers. I'd have thought that the existing stuff would be near-useless without the capabilities which you describe? - 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/