From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1KyPY4-0004aU-4e for qemu-devel@nongnu.org; Fri, 07 Nov 2008 06:30:44 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1KyPY3-0004Zr-DH for qemu-devel@nongnu.org; Fri, 07 Nov 2008 06:30:43 -0500 Received: from [199.232.76.173] (port=34006 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1KyPY3-0004Zc-4l for qemu-devel@nongnu.org; Fri, 07 Nov 2008 06:30:43 -0500 Received: from smtp.eu.citrix.com ([62.200.22.115]:27413) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1KyPY2-0001g5-F7 for qemu-devel@nongnu.org; Fri, 07 Nov 2008 06:30:42 -0500 Message-ID: <491427A6.3070407@eu.citrix.com> Date: Fri, 07 Nov 2008 11:33:58 +0000 From: Stefano Stabellini MIME-Version: 1.0 Subject: Re: [Qemu-devel] vga optmization References: <20081103173111.GC30410@poweredge.glommer> <491034BC.2050806@eu.citrix.com> <49106171.5080209@redhat.com> <491063C1.4080202@eu.citrix.com> <20081104202846.GB27481@poweredge.glommer> <4911B0CE.5070108@eu.citrix.com> <20081107111547.GB15827@poweredge.glommer> In-Reply-To: <20081107111547.GB15827@poweredge.glommer> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Glauber Costa Cc: aliguori@us.ibm.com, qemu-devel@nongnu.org Glauber Costa wrote: > On Wed, Nov 05, 2008 at 02:42:22PM +0000, Stefano Stabellini wrote: >> Glauber Costa wrote: >> >>>> That's also how currently qemu-xen works. >>>> I am glad that we agree :) >>> I'm attaching a new version. Let me know if it's better this way. >>> >> >> >> Yes, this is much better thanks. >> >> I still have comments about possible improvements, so I wrote patch >> (against your patch). >> This patch is not meant to be applied, is only meant to be read (I believe >> that C code is more meaningful than English :). >> >> Some of the changes include: >> >> - instead of adding cirrus_lfb_addr, add a more generic lfb_addr to >> VGAState, so that can be reused in the future for possible stdvga only >> mappings; >> >> - instead of using cirrus_lfb_mapped as a boolean, use it as the >> mapping address, it is more useful that way; >> >> - instead of keeping the kvm dirty map always enabled, enable it only >> when the framebuffer is linear and in graphical mode; >> >> - look at the changes to vga.c, there is a simple check to reduce the >> dirty area to sync. >> >> It would be nice to check if the last two changes are actually a >> performance improvement. > I'm not opposed to the changes. I'll redo a patch and resend it today. > However, I'm not planning to include the last optimization you sent. > It is better that we do it in a separate commit. If you can get numbers, > even better. I'll try it myself too. Fine with me.