From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: [Qemu-devel] Re: [PATCH] Implement a virtio GPU transport Date: Mon, 01 Nov 2010 08:21:38 -0500 Message-ID: <4CCEBEE2.8010404@codemonkey.ws> References: <4CAC9CD1.2050601@collabora.co.uk> <4CB1D79A.6070805@redhat.com> <4CBD739A.2010500@collabora.co.uk> <4CBD7560.6080207@redhat.com> <4CC8226F.5080807@collabora.co.uk> <4CC94203.1080207@redhat.com> <4CC9647A.50108@collabora.co.uk> <4CC98784.7020907@redhat.com> <4CC9D472.2080109@collabora.co.uk> <4CCE9989.2010809@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4CCE9989.2010809@redhat.com> Sender: linux-kernel-owner@vger.kernel.org To: Avi Kivity Cc: Ian Molton , virtualization@lists.osdl.org, linux-kernel@vger.kernel.org, QEMU Developers List-Id: virtualization@lists.linuxfoundation.org On 11/01/2010 05:42 AM, Avi Kivity wrote: > On 10/28/2010 03:52 PM, Ian Molton wrote: >> On 28/10/10 15:24, Avi Kivity wrote: >>>> The caller is intended to block as the host must perform GL rendering >>>> before allowing the guests process to continue. >>> >>> Why is that? Can't we pipeline the process? >> >> No, not really. the guest may call for the scene to be rendered at >> any time and we have to wait for that to happen before we can return >> the data to it. > > Waiting for a response is fine, but can't the guest issue a second > batch while waiting for the first? In a threaded application I think you mean but all RPCs are dispatched holding a global lock so even within a threaded application, only a single GL call will be executed at a time. The other scenario would be multiple applications trying to use GL but AFAICT, this is not supported in the current model. Regards, Anthony Liguori