From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936076AbdCXOOb convert rfc822-to-8bit (ORCPT ); Fri, 24 Mar 2017 10:14:31 -0400 Received: from mga07.intel.com ([134.134.136.100]:34627 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757190AbdCXOOO (ORCPT ); Fri, 24 Mar 2017 10:14:14 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.36,215,1486454400"; d="scan'208";a="80238433" From: "Liang, Kan" To: Thomas Gleixner , Andi Kleen CC: "peterz@infradead.org" , "mingo@redhat.com" , "acme@kernel.org" , "linux-kernel@vger.kernel.org" , "eranian@google.com" , "jolsa@kernel.org" Subject: RE: [PATCH 0/3]measure SMI cost Thread-Topic: [PATCH 0/3]measure SMI cost Thread-Index: AQHSpARyK/EZaqE9Zk+BnaMVBcLFrKGjJ56AgAAxNoCAAAeBAIAApDSA Date: Fri, 24 Mar 2017 14:14:03 +0000 Message-ID: <37D7C6CF3E00A74B8858931C1DB2F077536C3CBC@SHSMSX103.ccr.corp.intel.com> References: <1490293551-5552-1-git-send-email-kan.liang@intel.com> <20170324114051.GC9371@tassilo.jf.intel.com> In-Reply-To: Accept-Language: zh-CN, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiOThlZmIyNmMtYWY4MC00NTEzLWFjNDctNTM3NjA0MDRiYThhIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX0lDIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE1LjkuNi42IiwiVHJ1c3RlZExhYmVsSGFzaCI6ImVtRXZQczZweVRHZXppbDF1Q3FmcEZrK3NrbVVZdEV5b0NCT1g5R1JBWjg9In0= x-ctpclassification: CTP_IC x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > > > > A new --smi-cost mode in perf stat is implemented to measure the > > > > SMI cost by calculating cycles and aperf results. In practice, the > > > > percentages of SMI cycles should be more useful than absolute value. > > > > > > That's only true for performance oriented analysis, but for > > > analyzing the root cause of latencies the actual cycles are definitely > interesting. > > > > perf stat also prints the absolute cycles of course (unless you do > > --metric-only) > > So much for the theory. From the patch: > > + if (!force_metric_only) > + metric_only = true; > The metric_only will be set by default in the patch. If user wants to get the actual cycles, they can apply --no-metric-only. Do you want me to make it clear in the changelog? Or you just don't like that "metric_only=true" is set by default? Thanks, Kan