From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0F3F5C352AA for ; Tue, 1 Oct 2019 18:48:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D03C221855 for ; Tue, 1 Oct 2019 18:48:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569955710; bh=GNgNrUswTuvHulo9vmyBNdCcYSawvC+U+jdWFB0IKyA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=eZD4aXLdxn5af28Lg5fBhNti6lG2lSW9uE6JuDq9WLKc1Lk/+MioaIiFqAJTiqPKH yiYe/YZIimqQJGAzfl/a9JQFxBRKwsT2z31Guq2X6DWsmT+gH4auoUqNGN5ET0r8S1 90Qn3QgFb8dsZXIhpXgwDWvihSkYJvtDss1fmVzk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725909AbfJASsa (ORCPT ); Tue, 1 Oct 2019 14:48:30 -0400 Received: from mail.kernel.org ([198.145.29.99]:36952 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725844AbfJASsa (ORCPT ); Tue, 1 Oct 2019 14:48:30 -0400 Received: from localhost (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 52F3120B7C; Tue, 1 Oct 2019 18:48:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569955709; bh=GNgNrUswTuvHulo9vmyBNdCcYSawvC+U+jdWFB0IKyA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=erK6Grjo4aC6WkHaCceBQ+bGig2oyXgyMli+uxdawFNMuoPz3ptlHI20zYnrieCdU DH7OOYU9vc/9njBGuy7uy4PfYeLd9Uh8a+RY1FFmytt9TO1CwQHXQsyOdJ04V8Ogsu DpqPyFfJN64LOCdPZCl/4MKpJVDaxghK2+7Ki9Hw= Date: Tue, 1 Oct 2019 14:48:28 -0400 From: Sasha Levin To: Michael Kelley Cc: Wei Hu , "rdunlap@infradead.org" , "shc_work@mail.ru" , "gregkh@linuxfoundation.org" , "lee.jones@linaro.org" , "alexandre.belloni@bootlin.com" , "baijiaju1990@gmail.com" , "info@metux.net" , "linux-hyperv@vger.kernel.org" , "dri-devel@lists.freedesktop.org" , "linux-fbdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Stephen Hemminger , Haiyang Zhang , KY Srinivasan , Dexuan Cui Subject: Re: [PATHC v6] video: hyperv: hyperv_fb: Support deferred IO for Hyper-V frame buffer driver Message-ID: <20191001184828.GF8171@sasha-vm> References: <20190918060227.6834-1-weh@microsoft.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-hyperv-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org On Fri, Sep 20, 2019 at 05:26:34PM +0000, Michael Kelley wrote: >From: Michael Kelley Sent: Wednesday, September 18, 2019 2:48 PM >> > >> > Without deferred IO support, hyperv_fb driver informs the host to refresh >> > the entire guest frame buffer at fixed rate, e.g. at 20Hz, no matter there >> > is screen update or not. This patch supports deferred IO for screens in >> > graphics mode and also enables the frame buffer on-demand refresh. The >> > highest refresh rate is still set at 20Hz. >> > >> > Currently Hyper-V only takes a physical address from guest as the starting >> > address of frame buffer. This implies the guest must allocate contiguous >> > physical memory for frame buffer. In addition, Hyper-V Gen 2 VMs only >> > accept address from MMIO region as frame buffer address. Due to these >> > limitations on Hyper-V host, we keep a shadow copy of frame buffer >> > in the guest. This means one more copy of the dirty rectangle inside >> > guest when doing the on-demand refresh. This can be optimized in the >> > future with help from host. For now the host performance gain from deferred >> > IO outweighs the shadow copy impact in the guest. >> > >> > Signed-off-by: Wei Hu > >Sasha -- this patch and one other from Wei Hu for the Hyper-V frame buffer >driver should be ready. Both patches affect only the Hyper-V frame buffer >driver so can go through the Hyper-V tree. Can you pick these up? Thx. I can't get this to apply anywhere, what tree is it based on? -- Thanks, Sasha