From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by mx.groups.io with SMTP id smtpd.web12.53939.1584974256048581689 for ; Mon, 23 Mar 2020 07:37:36 -0700 Authentication-Results: mx.groups.io; dkim=missing; spf=pass (domain: intel.com, ip: 192.55.52.88, mailfrom: ray.ni@intel.com) IronPort-SDR: hzkevPSJ1VsaOKoBiDscXyTZeHVKGVSjPd/hOdHjgQbWAHk4LV+7q43bsMh6UsE/Lu0EOuWTRk /emBd/Fv4Ilg== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Mar 2020 07:37:34 -0700 IronPort-SDR: 3lWdmZ1uyhV+f73cMfQfoR61lXsWLlXSRCQmUtteeFJQdPJGarOccvyOCCzlmTHhF2lfJpx4/A Tqbb3QBENG3g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.72,296,1580803200"; d="scan'208";a="239409608" Received: from fmsmsx107.amr.corp.intel.com ([10.18.124.205]) by fmsmga008.fm.intel.com with ESMTP; 23 Mar 2020 07:37:35 -0700 Received: from fmsmsx102.amr.corp.intel.com (10.18.124.200) by fmsmsx107.amr.corp.intel.com (10.18.124.205) with Microsoft SMTP Server (TLS) id 14.3.439.0; Mon, 23 Mar 2020 07:37:35 -0700 Received: from shsmsx152.ccr.corp.intel.com (10.239.6.52) by FMSMSX102.amr.corp.intel.com (10.18.124.200) with Microsoft SMTP Server (TLS) id 14.3.439.0; Mon, 23 Mar 2020 07:37:34 -0700 Received: from shsmsx104.ccr.corp.intel.com ([169.254.5.206]) by SHSMSX152.ccr.corp.intel.com ([169.254.6.155]) with mapi id 14.03.0439.000; Mon, 23 Mar 2020 22:37:32 +0800 From: "Ni, Ray" To: Laszlo Ersek , "devel@edk2.groups.io" , "Wu, Hao A" , "rfc@edk2.groups.io" CC: "Dong, Eric" , "Kinney, Michael D" , "Zeng, Star" Subject: Re: [edk2-devel] [RFC][PATCH v1] UefiCpuPkg/MpInitLib DXE: Reduce AP status check interval Thread-Topic: [edk2-devel] [RFC][PATCH v1] UefiCpuPkg/MpInitLib DXE: Reduce AP status check interval Thread-Index: AQHV+Ww19KJJMagtC0Gp9oHY1yVHwKhKbtsAgAsth4CAALGmoA== Date: Mon, 23 Mar 2020 14:37:32 +0000 Message-ID: <734D49CCEBEEF84792F5B80ED585239D5C4A88A9@SHSMSX104.ccr.corp.intel.com> References: <20200313132229.7628-1-hao.a.wu@intel.com> <6bf39348-1fcb-fd14-bc16-dd026ed200ad@redhat.com> <734D49CCEBEEF84792F5B80ED585239D5C49B8BF@SHSMSX104.ccr.corp.intel.com> In-Reply-To: Accept-Language: en-US, zh-CN X-MS-Has-Attach: X-MS-TNEF-Correlator: dlp-product: dlpe-windows dlp-version: 11.2.0.6 dlp-reaction: no-action x-originating-ip: [10.239.127.40] MIME-Version: 1.0 Return-Path: ray.ni@intel.com Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable > > Laszlo, > > Adding a PCD means platform integrators need to consider which value to= set. > > Most of the time, they may just use the default PCD value. > > Then, why not we add the PCD later when a real case is met? >=20 > The patch changes existent behavior; it is not for a newly introduced > feature. >=20 > Because most platforms are not in the edk2 tree, we don't know what > platforms could be regressed by increasing the polling frequency > tenfold. (And remember that the polling action has O(n) cost, where "n" > is the logical processor count.) >=20 > Under your suggestion, the expression "real case is met" amounts to > "someone reports a regression" (possibly after the next stable tag, > even). I don't think that's a good idea. > In particular, the patch is motivated by RegisterCpuFeaturesLib -- the > CpuFeaturesInitialize() function -- on some platform(s) that Hao uses. > But there are platforms that don't use RegisterCpuFeaturesLib, and still > use MpInitLib. OK. I agree with your suggestion.