From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [PATCH v3 11/24] xen/arm: Let the toolstack configure the number of SPIs Date: Fri, 20 Feb 2015 17:31:03 +0000 Message-ID: <54E76F57.2090807@linaro.org> References: <1421159133-31526-1-git-send-email-julien.grall@linaro.org> <1421159133-31526-12-git-send-email-julien.grall@linaro.org> <1424449399.30924.339.camel@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YOrQJ-0005G7-Oz for xen-devel@lists.xenproject.org; Fri, 20 Feb 2015 17:31:31 +0000 Received: by wevk48 with SMTP id k48so6923468wev.3 for ; Fri, 20 Feb 2015 09:31:30 -0800 (PST) In-Reply-To: <1424449399.30924.339.camel@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Campbell Cc: Wei Liu , Ian Jackson , tim@xen.org, stefano.stabellini@citrix.com, Jan Beulich , xen-devel@lists.xenproject.org List-Id: xen-devel@lists.xenproject.org Hi Ian, On 20/02/15 16:23, Ian Campbell wrote: > On Tue, 2015-01-13 at 14:25 +0000, Julien Grall wrote: >> Each domain may have a different number of IRQs depending on the devices >> assigned to it. >> >> Rather re-using the number of IRQs used by the hardwared GIC, let the > ^than and "hardware" (although "physical" might be better) > >> toolstack specify the number of SPIs when the domain is created. This >> will avoid to waste memory. > > "will avoid wasting memory". > >> To calculate the number of SPIs, we assume that any IRQ given via the option >> "irqs=" in xl is mapped 1:1 to the guest. > > I don't see any xl changes here, and I think all that really matters is > the semantics of the libxl_domain_build_info.irqs[] array, which > currently I think can only express 1:1 mappings anyway. > So: > > "To calculate the number of SPIs, we take advantage of the fact that the > libxl interface can only expose a 1:1 mapping and look for the largest > SPI in the list" or something. I will use this. Regards, -- Julien Grall