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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 106F8C3A5A1 for ; Wed, 28 Aug 2019 09:37:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E1CC22173E for ; Wed, 28 Aug 2019 09:37:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726614AbfH1JhG (ORCPT ); Wed, 28 Aug 2019 05:37:06 -0400 Received: from mga01.intel.com ([192.55.52.88]:35109 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726340AbfH1JhF (ORCPT ); Wed, 28 Aug 2019 05:37:05 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 28 Aug 2019 02:37:05 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,440,1559545200"; d="scan'208";a="264592725" Received: from shao2-debian.sh.intel.com (HELO [10.239.13.6]) ([10.239.13.6]) by orsmga001.jf.intel.com with ESMTP; 28 Aug 2019 02:37:03 -0700 Subject: Re: [LKP] [drm/mgag200] 90f479ae51: vm-scalability.median -18.8% regression To: Thomas Zimmermann , Feng Tang Cc: Stephen Rothwell , michel@daenzer.net, lkp@01.org, linux-kernel@vger.kernel.org, dri-devel References: <14fdaaed-51c8-b270-b46b-cba7b5c4ba52@suse.de> <20190805070200.GA91650@shbuild999.sh.intel.com> <045a23ab-78f7-f363-4a2e-bf24a7a2f79e@suse.de> <37ae41e4-455d-c18d-5c93-7df854abfef9@intel.com> <370747ca-4dc9-917b-096c-891dcc2aedf0@suse.de> <20190812072545.GA63191@shbuild999.sh.intel.com> <20190813093616.GA65475@shbuild999.sh.intel.com> <64d41701-55a4-e526-17ae-8936de4bc1ef@suse.de> <20190824051605.GA63850@shbuild999.sh.intel.com> <1b897bfe-fd40-3ae3-d867-424d1fc08c44@suse.de> <44029e80-ba00-8246-dec0-fda122d53f5e@suse.de> From: Rong Chen Message-ID: <90e78ce8-d46a-5154-c324-a05aa1743c98@intel.com> Date: Wed, 28 Aug 2019 17:37:01 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <44029e80-ba00-8246-dec0-fda122d53f5e@suse.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Thomas, On 8/28/19 1:16 AM, Thomas Zimmermann wrote: > Hi > > Am 27.08.19 um 14:33 schrieb Chen, Rong A: >> Both patches have little impact on the performance from our side. > Thanks for testing. Too bad they doesn't solve the issue. > > There's another patch attached. Could you please tests this as well? > Thanks a lot! > > The patch comes from Daniel Vetter after discussing the problem on IRC. > The idea of the patch is that the old mgag200 code might display much > less frames that the generic code, because mgag200 only prints from > non-atomic context. If we simulate this with the generic code, we should > see roughly the original performance. > > It's cool, the patch "usecansleep.patch" can fix the issue. commit:   f1f8555dfb9 drm/bochs: Use shadow buffer for bochs framebuffer console   90f479ae51a drm/mgag200: Replace struct mga_fbdev with generic framebuffer emulation   b976b04c2bc only schedule worker from non-atomic context f1f8555dfb9a70a2  90f479ae51afa45efab97afdde b976b04c2bcf33148d6c7bc1a2  testcase/testparams/testbox ----------------  -------------------------- --------------------------  ---------------------------          %stddev      change         %stddev      change %stddev              \          |                \          | \      42912             -15%      36517 44093 vm-scalability/performance-300s-8T-anon-cow-seq-hugetlb/lkp-knm01      42912             -15%      36517 44093        GEO-MEAN vm-scalability.median Best Regards, Rong Chen