From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751880Ab2ITJLf (ORCPT ); Thu, 20 Sep 2012 05:11:35 -0400 Received: from nat28.tlf.novell.com ([130.57.49.28]:44921 "EHLO nat28.tlf.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750847Ab2ITJLe convert rfc822-to-8bit (ORCPT ); Thu, 20 Sep 2012 05:11:34 -0400 Message-Id: <505AF9F6020000780009C909@nat28.tlf.novell.com> X-Mailer: Novell GroupWise Internet Agent 12.0.0 Date: Thu, 20 Sep 2012 10:11:50 +0100 From: "Jan Beulich" To: "Oliver Chick" Cc: "xen-devel@lists.xen.org" , "konrad.wilk@oracle.com" , "linux-kernel@vger.kernel.org" Subject: Re: [Xen-devel] [PATCH] Persistent grant maps for xen blk drivers References: <1348051887-21885-1-git-send-email-oliver.chick@citrix.com> <5059D0C8020000780009C4CF@nat28.tlf.novell.com> <1348131088.24539.2.camel@oliverchick-Precision-WorkStation-T3400> In-Reply-To: <1348131088.24539.2.camel@oliverchick-Precision-WorkStation-T3400> 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 >>> On 20.09.12 at 10:51, Oliver Chick wrote: > Ah yes, you're right - rings can accomodate 64 requests. ijc, and myself > got muddled. It also explains the comment in my summary that we only use > the first 60-ish persistent grants! > > With multipage rings, this will probably become a function, rather than > a constant. Does that sound sensible? Yes, that's what I was expecting. Whether a separate function/ macro is necessary is unclear, as it's simply __RING_SIZE(). Jan