From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: Xen/arm: Virtual ITS command queue handling Date: Tue, 5 May 2015 14:54:42 +0100 Message-ID: <5548CBA2.9040606@citrix.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Stefano Stabellini , Vijay Kilari Cc: Ian Campbell , Prasun Kapoor , manish.jaggi@caviumnetworks.com, Julien Grall , "xen-devel@lists.xen.org" , Stefano Stabellini List-Id: xen-devel@lists.xenproject.org On 05/05/15 14:51, Stefano Stabellini wrote: >> - With this irq/LPI descriptor we can identify the domain/vITS. >> - Info of all the ongoing ITS requests(put in pITS Queue) of this domain is >> stored in ITS command status array (called its_requests). This is >> managed per vITS. >> >> 1) Trap of CWRITER write by guest >> 2) Take vITS lock >> 3) Read all the commands written by guest, translate it >> - If one of the guest command is INT command >> a) Append INT command with completion_irq and write this batch as >> seperate request and goto (3) to process next commands >> - If more than 'n' commands are sent by guest, start a timer to process >> remaining commands >> 4) Append INT command with completion_irq of current domain > > I would consider adding a vcpu_block call I don't think the vcpu_block would improve performance here. Regards, -- Julien Grall