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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 A2425C43441 for ; Thu, 15 Nov 2018 14:26:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7560D2146D for ; Thu, 15 Nov 2018 14:26:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7560D2146D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388467AbeKPAe4 (ORCPT ); Thu, 15 Nov 2018 19:34:56 -0500 Received: from mga14.intel.com ([192.55.52.115]:23848 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732953AbeKPAez (ORCPT ); Thu, 15 Nov 2018 19:34:55 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 15 Nov 2018 06:26:51 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,236,1539673200"; d="scan'208";a="92293579" Received: from linux.intel.com ([10.54.29.200]) by orsmga008.jf.intel.com with ESMTP; 15 Nov 2018 06:26:52 -0800 Received: from [10.251.29.1] (kliang2-mobl1.ccr.corp.intel.com [10.251.29.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by linux.intel.com (Postfix) with ESMTPS id 8B8FD580475; Thu, 15 Nov 2018 06:26:51 -0800 (PST) Subject: Re: [PATCH 1/2] perf vendor events: Add stepping in CPUID string for x86 To: Jiri Olsa Cc: acme@kernel.org, mingo@redhat.com, peterz@infradead.org, linux-kernel@vger.kernel.org, namhyung@kernel.org, ak@linux.intel.com References: <20181114212416.15665-1-kan.liang@linux.intel.com> <20181115135347.GI9600@krava> From: "Liang, Kan" Message-ID: <7a63fdf4-828f-0685-e146-6d3d86d8655b@linux.intel.com> Date: Thu, 15 Nov 2018 09:26:50 -0500 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20181115135347.GI9600@krava> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/15/2018 8:53 AM, Jiri Olsa wrote: > On Wed, Nov 14, 2018 at 01:24:15PM -0800, kan.liang@linux.intel.com wrote: > > SNIP > >> diff --git a/tools/perf/arch/x86/util/header.c b/tools/perf/arch/x86/util/header.c >> index fb0d71afee8b..b428a4b00bf7 100644 >> --- a/tools/perf/arch/x86/util/header.c >> +++ b/tools/perf/arch/x86/util/header.c >> @@ -4,6 +4,7 @@ >> #include >> #include >> #include >> +#include >> >> #include "../../util/header.h" >> >> @@ -70,9 +71,73 @@ get_cpuid_str(struct perf_pmu *pmu __maybe_unused) >> { >> char *buf = malloc(128); >> >> - if (buf && __get_cpuid(buf, 128, "%s-%u-%X$") < 0) { >> + if (buf && __get_cpuid(buf, 128, "%s-%u-%X-%X$") < 0) { >> free(buf); >> return NULL; >> } >> return buf; >> } >> + >> +/* Full CPUID format for x86 is vendor-family-model-stepping */ >> +static bool is_full_cpuid(const char *cpuid) >> +{ >> + const char *tmp = cpuid; >> + int count = 0; >> + >> + while ((tmp = strchr(tmp, '-')) != NULL) { >> + count++; >> + tmp++; >> + } >> + >> + if (count == 3) >> + return true; >> + >> + return false; >> +} >> + >> +int strcmp_cpuid_str(const char *mapcpuid, const char *cpuid) >> +{ >> + regex_t re; >> + regmatch_t pmatch[1]; >> + int match; >> + bool full_mapcpuid = is_full_cpuid(mapcpuid); >> + bool full_cpuid = is_full_cpuid(cpuid); > > cpuid will be always full from now right? why do we need to check it? > User may set cpuid by environment string "PERF_CPUID", which may not be full format. > also please move this to arch/x86/util/pmu.c > so it matches the weak function object Sure. > >> + >> + /* >> + * Full CPUID format is required to identify a platform. >> + * Error out if the cpuid string is incomplete. >> + */ >> + if (full_mapcpuid && !full_cpuid) { >> + pr_info("Invalid CPUID %s. Full CPUID is required, " >> + "vendor-family-model-stepping\n", cpuid); >> + return 1; >> + } >> + >> + if (regcomp(&re, mapcpuid, REG_EXTENDED) != 0) { >> + /* Warn unable to generate match particular string. */ >> + pr_info("Invalid regular expression %s\n", mapcpuid); >> + return 1; >> + } >> + >> + match = !regexec(&re, cpuid, 1, pmatch, 0); >> + regfree(&re); >> + if (match) { >> + size_t match_len = (pmatch[0].rm_eo - pmatch[0].rm_so); >> + size_t cpuid_len; >> + >> + /* If the full CPUID format isn't required, >> + * ignoring the stepping. >> + */ >> + if (!full_mapcpuid && full_cpuid) >> + cpuid_len = strrchr(cpuid, '-') - cpuid; >> + else >> + cpuid_len = strlen(cpuid); >> + >> + >> + /* Verify the entire string matched. */ >> + if (match_len == cpuid_len) >> + return 0; > > why is this necessary? > It's from previous common code. As my understanding, it just double check the matched strings. There is no harmful. So I keep it. Thanks, Kan