From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753533Ab0IQJf0 (ORCPT ); Fri, 17 Sep 2010 05:35:26 -0400 Received: from claranet-outbound-smtp00.uk.clara.net ([195.8.89.33]:45249 "EHLO claranet-outbound-smtp00.uk.clara.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752215Ab0IQJfV convert rfc822-to-8bit (ORCPT ); Fri, 17 Sep 2010 05:35:21 -0400 X-Greylist: delayed 1981 seconds by postgrey-1.27 at vger.kernel.org; Fri, 17 Sep 2010 05:35:21 EDT From: Simon Farnsworth To: intel-gfx@lists.freedesktop.org Subject: Re: [Intel-gfx] Interrupt latency on some 945GM platforms Date: Fri, 17 Sep 2010 10:02:08 +0100 User-Agent: KMail/1.13.3 (Linux/2.6.34.1-100.tv.pf.fc13.x86_64; KDE/4.4.4; x86_64; ; ) Cc: Vasily Khoruzhick , Sitsofe Wheeler , Venkatesh Pallipadi , Thomas Gleixner , linux-kernel@vger.kernel.org, Jesse Barnes References: <201009132336.17310.anarsoul@gmail.com> <20100914224111.GA14467@sucs.org> <201009161803.10531.anarsoul@gmail.com> In-Reply-To: <201009161803.10531.anarsoul@gmail.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 8BIT Message-Id: <201009171002.09187.simon.farnsworth@onelan.co.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thursday 16 September 2010, Vasily Khoruzhick wrote: > В сообщении от 15 of September 2010 01:41:11 автор Sitsofe Wheeler написал: > > > > processor.max_cstate=2 > > > > > > Nope, it doesn't work with max_cstate=2 > > > > Perhaps intel_idle is being used? Any mention of it in dmesg? > > Sitsofe, maybe you misunderstood me, I mean with max_cstate=1 graphics is > smooth, with higher values (i.e. max_cstate=2) graphics is jerky. > > Btw, Jesse, any comments/solutions/workarounds except one with > processor.max_cstate=1 in kernel commandline? Should I file a bug on fdo > bugzilla? This looks like a problem I've seen on some hardware. My workaround has been to use the pm_qos /dev/cpu_dma_latency interface to request a maximum latency of 1ms (value chosen as definitely small enough - a larger value may be better, but I don't care about power saving at runtime on my kit). If it's happening on other kit, perhaps the i915 driver should make a suitable pm_qos request itself. Jesse, can you comment? -- Simon Farnsworth Software Engineer ONELAN Limited http://www.onelan.com/ From mboxrd@z Thu Jan 1 00:00:00 1970 From: Simon Farnsworth Subject: Re: Interrupt latency on some 945GM platforms Date: Fri, 17 Sep 2010 10:02:08 +0100 Message-ID: <201009171002.09187.simon.farnsworth@onelan.co.uk> References: <201009132336.17310.anarsoul@gmail.com> <20100914224111.GA14467@sucs.org> <201009161803.10531.anarsoul@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from claranet-outbound-smtp00.uk.clara.net (claranet-outbound-smtp00.uk.clara.net [195.8.89.33]) by gabe.freedesktop.org (Postfix) with ESMTP id 921F19E7D7 for ; Fri, 17 Sep 2010 02:02:16 -0700 (PDT) In-Reply-To: <201009161803.10531.anarsoul@gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: intel-gfx@lists.freedesktop.org Cc: Venkatesh Pallipadi , Sitsofe Wheeler , linux-kernel@vger.kernel.org, Thomas Gleixner List-Id: intel-gfx@lists.freedesktop.org T24gVGh1cnNkYXkgMTYgU2VwdGVtYmVyIDIwMTAsIFZhc2lseSBLaG9ydXpoaWNrIDxhbmFyc291 bEBnbWFpbC5jb20+IHdyb3RlOgo+INCSINGB0L7QvtCx0YnQtdC90LjQuCDQvtGCIDE1IG9mIFNl cHRlbWJlciAyMDEwIDAxOjQxOjExINCw0LLRgtC+0YAgU2l0c29mZSBXaGVlbGVyINC90LDQv9C4 0YHQsNC7Ogo+ID4gPiA+ICAgICBwcm9jZXNzb3IubWF4X2NzdGF0ZT0yCj4gPiA+IAo+ID4gPiBO b3BlLCBpdCBkb2Vzbid0IHdvcmsgd2l0aCBtYXhfY3N0YXRlPTIKPiA+IAo+ID4gUGVyaGFwcyBp bnRlbF9pZGxlIGlzIGJlaW5nIHVzZWQ/IEFueSBtZW50aW9uIG9mIGl0IGluIGRtZXNnPwo+IAo+ IFNpdHNvZmUsIG1heWJlIHlvdSBtaXN1bmRlcnN0b29kIG1lLCBJIG1lYW4gd2l0aCBtYXhfY3N0 YXRlPTEgZ3JhcGhpY3MgaXMKPiBzbW9vdGgsIHdpdGggaGlnaGVyIHZhbHVlcyAoaS5lLiBtYXhf Y3N0YXRlPTIpIGdyYXBoaWNzIGlzIGplcmt5Lgo+IAo+IEJ0dywgSmVzc2UsIGFueSBjb21tZW50 cy9zb2x1dGlvbnMvd29ya2Fyb3VuZHMgZXhjZXB0IG9uZSB3aXRoCj4gcHJvY2Vzc29yLm1heF9j c3RhdGU9MSBpbiBrZXJuZWwgY29tbWFuZGxpbmU/IFNob3VsZCBJIGZpbGUgYSBidWcgb24gZmRv Cj4gYnVnemlsbGE/CgpUaGlzIGxvb2tzIGxpa2UgYSBwcm9ibGVtIEkndmUgc2VlbiBvbiBzb21l IGhhcmR3YXJlLgoKTXkgd29ya2Fyb3VuZCBoYXMgYmVlbiB0byB1c2UgdGhlIHBtX3FvcyAvZGV2 L2NwdV9kbWFfbGF0ZW5jeSBpbnRlcmZhY2UgdG8gCnJlcXVlc3QgYSBtYXhpbXVtIGxhdGVuY3kg b2YgMW1zICh2YWx1ZSBjaG9zZW4gYXMgZGVmaW5pdGVseSBzbWFsbCBlbm91Z2ggLSBhIApsYXJn ZXIgdmFsdWUgbWF5IGJlIGJldHRlciwgYnV0IEkgZG9uJ3QgY2FyZSBhYm91dCBwb3dlciBzYXZp bmcgYXQgcnVudGltZSBvbiAKbXkga2l0KS4KCklmIGl0J3MgaGFwcGVuaW5nIG9uIG90aGVyIGtp dCwgcGVyaGFwcyB0aGUgaTkxNSBkcml2ZXIgc2hvdWxkIG1ha2UgYSBzdWl0YWJsZSAKcG1fcW9z IHJlcXVlc3QgaXRzZWxmLiBKZXNzZSwgY2FuIHlvdSBjb21tZW50PwotLSAKU2ltb24gRmFybnN3 b3J0aApTb2Z0d2FyZSBFbmdpbmVlcgpPTkVMQU4gTGltaXRlZApodHRwOi8vd3d3Lm9uZWxhbi5j b20vCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCkludGVs LWdmeCBtYWlsaW5nIGxpc3QKSW50ZWwtZ2Z4QGxpc3RzLmZyZWVkZXNrdG9wLm9yZwpodHRwOi8v bGlzdHMuZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlzdGluZm8vaW50ZWwtZ2Z4Cg==