From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [PATCH V5 02/10] xen/arm: Add functions of mapping between vCPUID and virtual affinity Date: Sun, 31 May 2015 13:51:38 +0100 Message-ID: <556B03DA.8080907@citrix.com> References: <1432984051-10838-1-git-send-email-cbz@baozis.org> <1432984051-10838-3-git-send-email-cbz@baozis.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1Yz2iO-000379-2V for xen-devel@lists.xenproject.org; Sun, 31 May 2015 12:51:44 +0000 In-Reply-To: <1432984051-10838-3-git-send-email-cbz@baozis.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Chen Baozi , xen-devel@lists.xenproject.org Cc: Julien Grall , Chen Baozi , Ian Campbell List-Id: xen-devel@lists.xenproject.org Hi Chen, On 30/05/2015 12:07, Chen Baozi wrote: > From: Chen Baozi > > GICv3 restricts that the maximum number of CPUs in affinity 0 (one > cluster) is 16. That is to say the upper 4 bits of affinity 0 is unused. > Current implementation considers that AFF0 is equal to vCPUID, which > makes all vCPUs in one cluster, limiting its number to 16. If we would > like to support more than 16 number of vCPU in one guest, we need to > make use of AFF1. Considering the unused upper 4 bits, we need to create > a pair of functions mapping the vCPUID and virtual affinity. > > Signed-off-by: Chen Baozi Reviewed-by: Julien Grall Regards, -- Julien Grall