From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Roper Subject: Re: [BUG, bisect] drm/i915: mouse pointer lags and overshoots Date: Mon, 19 Jan 2015 08:40:24 -0800 Message-ID: <20150119164024.GI22549@intel.com> References: <20150117100635.GA1281@hudson.localdomain> <20150119090847.GQ10649@intel.com> <54BCE1BF.5050808@intel.com> <20150119110404.GA26577@nuc-i3427.alporthouse.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Content-Disposition: inline In-Reply-To: <20150119110404.GA26577@nuc-i3427.alporthouse.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Chris Wilson , Daniel Vetter , Ville =?iso-8859-1?Q?Syrj=E4l=E4?= , Jeremiah Mahler , Jani Nikula , David Airlie , Alex Deucher , Dave Airlie , Ander Conselvan de Oliveira , linux-kernel@vger.kernel.org, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org T24gTW9uLCBKYW4gMTksIDIwMTUgYXQgMTE6MDQ6MDRBTSArMDAwMCwgQ2hyaXMgV2lsc29uIHdy b3RlOgo+IE9uIE1vbiwgSmFuIDE5LCAyMDE1IGF0IDExOjUxOjQzQU0gKzAxMDAsIERhbmllbCBW ZXR0ZXIgd3JvdGU6Cj4gPiBUaGVyZSdzIGFsc28gYW4gaXNzdWUgaW4gKG1vc3QpIFggZHJpdmVy cyB3aGljaCBleGFiZXJhdGVzIHRoaXMKPiA+IGlzc3VlczogV2hlbiBjaGFuZ2luZyB0aGUgY3Vy c29yIGJ1ZmZlciB0aGUgWCBjdXJzb3IgY29kZSBkb2VzIGEgYSkKPiA+IGRpc2FibGUgY3Vyc29y IGIpIHVwZGF0ZSBjdXJzb3IgaW1hZ2UgYykgZW5hYmxlIGN1cnNvciBjeWNsZS4KPiAKPiBOb3Rh Ymx5IG5vdCAtaW50ZWwgb24gd2hpY2ggdGhlIGJ1ZyBoYXMgYmVlbiBvYnNlcnZlZC4gQW5kIG1v cmUKPiBpbXBvcnRhbnRseSwgdGhlIHNsb3cgZG93bnMgZG9uJ3Qgc2VlbSB0byBjb3JyZWxhdGUg d2l0aCBjdXJzb3IgY2hhbmdlLAo+IGp1c3QgY3Vyc29yIG1vdmVtZW50Lgo+IC1DaHJpcwo+IAo+ IC0tIAo+IENocmlzIFdpbHNvbiwgSW50ZWwgT3BlbiBTb3VyY2UgVGVjaG5vbG9neSBDZW50cmUK Ckl0IHNlZW1zIHRoYXQgdGhlIHNpbXBsZSBmaXggZm9yIHRoaXMgY2FzZSAobW92ZW1lbnQgb25s eSkgaXMgdG8ganVzdApza2lwIHRoZSBwcmVwYXJlX2ZiL2NsZWFudXBfZmIgY2FsbHMgKGFuZCB0 aGUgYXNzb2NpYXRlZCB2Ymxhbmsgd2FpdCkgaW4KdGhlIHRyYW5zaXRpb25hbCBwbGFuZSBoZWxw ZXIgd2hlbiBuZXdmYiA9PSBvbGRmYi4gIEkganVzdCBwb3N0ZWQgYQpzbWFsbCBwYXRjaCB0aGF0 IG1ha2VzIHRoYXQgY2hhbmdlIChhbmQgc29sdmVzIHRoZSBjdXJzb3IgbGFnIGZvciBtZSkuCgpU aGlzIHdvbid0IHNvbHZlIHRoZSBjYXNlIGlmIHVzZXJzcGFjZSB1c2VzIGEgZGlmZmVyZW50IGZy YW1lYnVmZmVyIGZvcgplYWNoIHVwZGF0ZSAod2hpbGUgdHJ5aW5nIHRvIHVwZGF0ZSBmYXN0ZXIg dGhhbiB0aGUgcmVmcmVzaCByYXRlKS4gIElzCnRoZXJlIGFueSBleGlzdGluZyB1c2Vyc3BhY2Ug dGhhdCBiZWhhdmVzIHRoaXMgd2F5IHRoYXQgd2UgY2FuIHRlc3QKd2l0aD8KCgpNYXR0CgotLSAK TWF0dCBSb3BlcgpHcmFwaGljcyBTb2Z0d2FyZSBFbmdpbmVlcgpJb1RHIFBsYXRmb3JtIEVuYWJs aW5nICYgRGV2ZWxvcG1lbnQKSW50ZWwgQ29ycG9yYXRpb24KKDkxNikgMzU2LTI3OTUKX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KSW50ZWwtZ2Z4IG1haWxp bmcgbGlzdApJbnRlbC1nZnhAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHA6Ly9saXN0cy5mcmVl ZGVza3RvcC5vcmcvbWFpbG1hbi9saXN0aW5mby9pbnRlbC1nZngK From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751936AbbASQkd (ORCPT ); Mon, 19 Jan 2015 11:40:33 -0500 Received: from mga03.intel.com ([134.134.136.65]:39730 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751166AbbASQkc (ORCPT ); Mon, 19 Jan 2015 11:40:32 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.09,428,1418112000"; d="scan'208";a="653237578" Date: Mon, 19 Jan 2015 08:40:24 -0800 From: Matt Roper To: Chris Wilson , Daniel Vetter , Ville =?iso-8859-1?Q?Syrj=E4l=E4?= , Jeremiah Mahler , Jani Nikula , David Airlie , Alex Deucher , Dave Airlie , Ander Conselvan de Oliveira , linux-kernel@vger.kernel.org, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org Subject: Re: [Intel-gfx] [BUG, bisect] drm/i915: mouse pointer lags and overshoots Message-ID: <20150119164024.GI22549@intel.com> References: <20150117100635.GA1281@hudson.localdomain> <20150119090847.GQ10649@intel.com> <54BCE1BF.5050808@intel.com> <20150119110404.GA26577@nuc-i3427.alporthouse.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150119110404.GA26577@nuc-i3427.alporthouse.com> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 19, 2015 at 11:04:04AM +0000, Chris Wilson wrote: > On Mon, Jan 19, 2015 at 11:51:43AM +0100, Daniel Vetter wrote: > > There's also an issue in (most) X drivers which exaberates this > > issues: When changing the cursor buffer the X cursor code does a a) > > disable cursor b) update cursor image c) enable cursor cycle. > > Notably not -intel on which the bug has been observed. And more > importantly, the slow downs don't seem to correlate with cursor change, > just cursor movement. > -Chris > > -- > Chris Wilson, Intel Open Source Technology Centre It seems that the simple fix for this case (movement only) is to just skip the prepare_fb/cleanup_fb calls (and the associated vblank wait) in the transitional plane helper when newfb == oldfb. I just posted a small patch that makes that change (and solves the cursor lag for me). This won't solve the case if userspace uses a different framebuffer for each update (while trying to update faster than the refresh rate). Is there any existing userspace that behaves this way that we can test with? Matt -- Matt Roper Graphics Software Engineer IoTG Platform Enabling & Development Intel Corporation (916) 356-2795