From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753783Ab1ILXid (ORCPT ); Mon, 12 Sep 2011 19:38:33 -0400 Received: from wolverine01.qualcomm.com ([199.106.114.254]:38664 "EHLO wolverine01.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756169Ab1ILXia (ORCPT ); Mon, 12 Sep 2011 19:38:30 -0400 X-IronPort-AV: E=McAfee;i="5400,1158,6467"; a="118002047" Date: Mon, 12 Sep 2011 18:38:27 -0500 From: Richard Kuo To: Benjamin Herrenschmidt Cc: linux-arch@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-kernel@vger.kernel.org, Linas Vepstas Subject: Re: [patch v3 21/36] Hexagon: Add SMP support Message-ID: <20110912233827.GB6925@codeaurora.org> References: <20110909010847.294039464@codeaurora.org> <20110909010916.709728186@codeaurora.org> <1315752712.455.50.camel@pasglop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1315752712.455.50.camel@pasglop> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Sep 11, 2011 at 11:51:52AM -0300, Benjamin Herrenschmidt wrote: > And on the producer side, a spinlock for one or... that looks like wheel > re-inventing to me :-) > > In fact your bit iteration loop also re-invents find_*_bit interfaces. > > Any reason why you don't simply use bitops or atomics here ? No particular reason; just the way it turned out when I was getting things working. I'll get them cleaned up. > Also what is your memory model ? ordered or weakly ordered ? Do you need > some kind of memory barrier between setting ipi->bits and > __vmintop_post() ? Our model is ordered, so there's no need for a barrier there yet. Thanks, Richard Kuo -- Sent by an employee of the Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.