From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932102AbbFOOFa (ORCPT ); Mon, 15 Jun 2015 10:05:30 -0400 Received: from mail-bn1on0136.outbound.protection.outlook.com ([157.56.110.136]:49504 "EHLO na01-bn1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753810AbbFOOFU (ORCPT ); Mon, 15 Jun 2015 10:05:20 -0400 Authentication-Results: spf=none (sender IP is 165.204.84.222) smtp.mailfrom=amd.com; amacapital.net; dkim=none (message not signed) header.d=none; X-WSS-ID: 0NPZOGQ-08-7DB-02 X-M-MSG: Date: Mon, 15 Jun 2015 22:04:19 +0800 From: Huang Rui To: Borislav Petkov CC: Peter Zijlstra , Andy Lutomirski , Thomas Gleixner , Ingo Molnar , "Rafael J. Wysocki" , Len Brown , John Stultz , =?iso-8859-1?Q?Fr=E9d=E9ric?= Weisbecker , , , Fengguang Wu , Aaron Lu , Suravee Suthikulanit , Tony Li , Ken Xue Subject: Re: [PATCH v5 2/2] x86, mwaitt: introduce mwaix delay with a configurable timer Message-ID: <20150615140418.GB28310@hr-slim.amd.com> References: <1434365284-1495-1-git-send-email-ray.huang@amd.com> <1434365284-1495-3-git-send-email-ray.huang@amd.com> <20150615105718.GW3644@twins.programming.kicks-ass.net> <20150615111526.GB4481@pd.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20150615111526.GB4481@pd.tnic> User-Agent: Mutt/1.5.21 (2010-09-15) X-EOPAttributedMessage: 0 X-Microsoft-Exchange-Diagnostics: 1;BN1BFFO11FD025;1:qMMoiSJv46bzTnp9et+H08fuTR9auTJgMWxfkR9t8cT4dlfalygZdW7f+byIKNSecshg5nHCckidRf66etmph3bEnsYLlgqKuZ9vRl6IBo6s8Ne8JYUfooXB3MIxzeil75sP9uLfj9UxaUkch3mj2IN8wUSWVHolIrxcRaMrZK59TWZc6n8pjmNXIQsWo7OFilCcQTKLYu35eTnuEhB43/4YfT43j5c6RLKU0SrNz/LP7l/APnF2ELnATi7Mrrgz8JSwY8b54eYm5c4M2VWqAd01RzprIsvNj7b1hdAcheyWJJ5zbyeJ/E1OZZXNSKmhAViLiSSitH5SklgPLu6DyHATf0zX12XBrvmeLoDMn1I= X-Forefront-Antispam-Report: CIP:165.204.84.222;CTRY:US;IPV:NLI;EFV:NLI;SFV:NSPM;SFS:(10019020)(6009001)(428002)(199003)(24454002)(189002)(164054003)(92566002)(101416001)(83506001)(76176999)(105586002)(50466002)(2950100001)(4001350100001)(93886004)(46406003)(106466001)(50986999)(47776003)(77096005)(53416004)(62966003)(23726002)(87936001)(5003600100002)(46102003)(54356999)(33656002)(5001920100001)(77156002)(86362001)(189998001)(110136002)(97756001);DIR:OUT;SFP:1102;SCL:1;SRVR:BLUPR02MB1108;H:atltwp02.amd.com;FPR:;SPF:None;MLV:sfv;A:1;MX:1;LANG:en; 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Because we have a > bunch of places where we do delay. > > Rui, what happens if you enter C1 instead? Any improvements or is the > wakeup latency too high? > Hmm, the current processor cannot enter C1 with MWAITX, so I don't confirm if it would have higher wakeup latency on C1 in future. Thanks, Rui