From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754323AbZLBOZp (ORCPT ); Wed, 2 Dec 2009 09:25:45 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752473AbZLBOZn (ORCPT ); Wed, 2 Dec 2009 09:25:43 -0500 Received: from vpn.id2.novell.com ([195.33.99.129]:52722 "EHLO vpn.id2.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754056AbZLBOZl convert rfc822-to-8bit (ORCPT ); Wed, 2 Dec 2009 09:25:41 -0500 Message-Id: <4B1686F702000078000230A6@vpn.id2.novell.com> X-Mailer: Novell GroupWise Internet Agent 8.0.1 Date: Wed, 02 Dec 2009 14:25:43 +0000 From: "Jan Beulich" To: "Avi Kivity" Cc: , "Ingo Molnar" , , , , , , , Subject: Re: [tip:core/locking] locking, x86: Slightly shorten __ticket_spin_trylock() References: <4B0FF9AC0200007800022713@vpn.id2.novell.com> <20091202132937.GA1564@elte.hu> <4B168293020000780002308E@vpn.id2.novell.com> <4B1675CA.1020504@redhat.com> In-Reply-To: <4B1675CA.1020504@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>> Avi Kivity 02.12.09 15:12 >>> >Wouldn't 'u8 ret', as an additional argument be sufficient? gcc still >ought to be able to use the same register for new and ret if we remove >the early clobber. We can't (validly) remove the early-clobber, otherwise the compiler would be permitted to use a register also used for addressing the lock structure for "new". Jan