Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763718AbZAOR5t (ORCPT ); Thu, 15 Jan 2009 12:57:49 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759556AbZAOR5l (ORCPT ); Thu, 15 Jan 2009 12:57:41 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:51040 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759310AbZAOR5k (ORCPT ); Thu, 15 Jan 2009 12:57:40 -0500 Date: Thu, 15 Jan 2009 18:57:35 +0100 From: Ingo Molnar To: Cliff Wickman Cc: linux-kernel@vger.kernel.org Subject: Re: [PATCH] UV: cpu_relax in uv_wait_completion Message-ID: <20090115175735.GH22472@elte.hu> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 785 Lines: 26 * Cliff Wickman wrote: > > From: Cliff Wickman > > The function uv_wait_completion() spins on reads of a memory-mapped > register, waiting for completion of BAU hardware replies. > It should call "cpu_relax()" between those reads to improve performance > on hyperthreaded configurations. > > Signed-off-by: Cliff Wickman > Acked-by: Jack Steiner > > --- > arch/x86/kernel/tlb_uv.c | 1 + > 1 file changed, 1 insertion(+) applied to tip/x86/urgent, thanks Cliff! Ingo -- 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/