Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263152AbTETA2O (ORCPT ); Mon, 19 May 2003 20:28:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263235AbTETA2O (ORCPT ); Mon, 19 May 2003 20:28:14 -0400 Received: from cpe-24-221-190-179.ca.sprintbbd.net ([24.221.190.179]:20622 "EHLO myware.akkadia.org") by vger.kernel.org with ESMTP id S263152AbTETA2M (ORCPT ); Mon, 19 May 2003 20:28:12 -0400 Message-ID: <3EC97996.1080800@redhat.com> Date: Mon, 19 May 2003 17:40:54 -0700 From: Ulrich Drepper Organization: Red Hat, Inc. User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4b) Gecko/20030516 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Rusty Russell CC: Ingo Molnar , Linus Torvalds , linux-kernel@vger.kernel.org Subject: Re: [patch] futex requeueing feature, futex-requeue-2.5.69-D3 References: <20030520001623.715822C08B@lists.samba.org> In-Reply-To: <20030520001623.715822C08B@lists.samba.org> X-Enigmail-Version: 0.75.0.0 X-Enigmail-Supports: pgp-inline, pgp-mime 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: 1630 Lines: 43 -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Rusty Russell wrote: > 1) Overload the last futex arg (change from timeval * to void *), > don't add YA arg at the end. It wasn't Ingo's idea. I suggested it. Overloading parameter types is evil. This isn't an issue anymore if the extension is implemented as a new syscall which certainly is better. > 2) Use __alignof__(u32) not sizeof(u32). Sure, they're the same, but > you really mean __alignof__ here. I would always use sizeof() in this situation. alignof is a property the compiler can potentially relax. On x86 it could easily be defined to 1 in case someone wants to save memory. OK, not really useful for x86, but some embedded archs might be in such a situation. Using sizeof() makes sure that the variable is always 4-byte aligned. For atomic operations this certainly is a good minimal requirement. If you want to really correct you might have to introduce something like atomic_alignof(). - -- - --------------. ,-. 444 Castro Street Ulrich Drepper \ ,-----------------' \ Mountain View, CA 94041 USA Red Hat `--' drepper at redhat.com `--------------------------- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.1 (GNU/Linux) iD8DBQE+yXmW2ijCOnn/RHQRAnXcAKCeYFvfkKIO/bbwqX1vUvbLkBvHKwCeN6zB 99qZZOVLMckvh6lxieUfVpY= =LvwT -----END PGP SIGNATURE----- - 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/