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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 14676C4724C for ; Wed, 6 May 2020 15:25:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E627F20CC7 for ; Wed, 6 May 2020 15:25:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588778736; bh=aBpiZ0CDnUe5OjSXDqD9oQ+ne/XZHBGUT1iXk3bbtdw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=j9lqJRYLpO/CYcJJF3KKzOdVvHKRwoh381Ip3OEdl5LskIEBBYyDzutTdinJb4R4M +9wPaOe2goENnUcm+OZ9rYUoxoVj4E4GA4C/k6uSVsaJy7iwm2lgmdrQhYy/2r0JYR 6BLWgYNYjTGvh0NI9VucJOKYYlGaYIZxfuEQypyQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730048AbgEFPZf (ORCPT ); Wed, 6 May 2020 11:25:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:45954 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730034AbgEFPZc (ORCPT ); Wed, 6 May 2020 11:25:32 -0400 Received: from quaco.ghostprotocols.net (unknown [179.97.37.151]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 85F8121744; Wed, 6 May 2020 15:25:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588778732; bh=aBpiZ0CDnUe5OjSXDqD9oQ+ne/XZHBGUT1iXk3bbtdw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NMtHRH5C3GeJtljtvRlquwK242ItIKa69F2F58GS20ak/JAq9GTBN6Kiwz84pRVa+ fVh1zRrYO9bZEs7u1hNwc/AXXFascossbJ80rn38wS2t3y6+6NRpzJTCHOi3ho63iF svlxt7uPszxWch7PLDwGOPWm4b4TMJFu7/Q67kfw= From: Arnaldo Carvalho de Melo To: Ingo Molnar , Thomas Gleixner Cc: Jiri Olsa , Namhyung Kim , Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Adrian Hunter , Andi Kleen , Jiri Olsa , Arnaldo Carvalho de Melo Subject: [PATCH 47/91] perf intel-pt: Update documentation about using /proc/kcore Date: Wed, 6 May 2020 12:21:50 -0300 Message-Id: <20200506152234.21977-48-acme@kernel.org> X-Mailer: git-send-email 2.21.1 In-Reply-To: <20200506152234.21977-1-acme@kernel.org> References: <20200506152234.21977-1-acme@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Adrian Hunter Update documentation to reflect the advent of the --kcore option for 'perf record'. Signed-off-by: Adrian Hunter Cc: Andi Kleen Cc: Jiri Olsa Link: http://lore.kernel.org/lkml/20200429150751.12570-10-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/perf-intel-pt.txt | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/tools/perf/Documentation/perf-intel-pt.txt b/tools/perf/Documentation/perf-intel-pt.txt index 782eb8a65caf..eb8b7d42591a 100644 --- a/tools/perf/Documentation/perf-intel-pt.txt +++ b/tools/perf/Documentation/perf-intel-pt.txt @@ -69,22 +69,22 @@ And profiled with 'perf report' e.g. To also trace kernel space presents a problem, namely kernel self-modifying code. A fairly good kernel image is available in /proc/kcore but to get an accurate image a copy of /proc/kcore needs to be made under the same conditions -as the data capture. A script perf-with-kcore can do that, but beware that the -script makes use of 'sudo' to copy /proc/kcore. If you have perf installed -locally from the source tree you can do: +as the data capture. 'perf record' can make a copy of /proc/kcore if the option +--kcore is used, but access to /proc/kcore is restricted e.g. - ~/libexec/perf-core/perf-with-kcore record pt_ls -e intel_pt// -- ls + sudo perf record -o pt_ls --kcore -e intel_pt// -- ls -which will create a directory named 'pt_ls' and put the perf.data file and -copies of /proc/kcore, /proc/kallsyms and /proc/modules into it. Then to use -'perf report' becomes: +which will create a directory named 'pt_ls' and put the perf.data file (named +simply 'data') and copies of /proc/kcore, /proc/kallsyms and /proc/modules into +it. The other tools understand the directory format, so to use 'perf report' +becomes: - ~/libexec/perf-core/perf-with-kcore report pt_ls + sudo perf report -i pt_ls Because samples are synthesized after-the-fact, the sampling period can be selected for reporting. e.g. sample every microsecond - ~/libexec/perf-core/perf-with-kcore report pt_ls --itrace=i1usge + sudo perf report pt_ls --itrace=i1usge See the sections below for more information about the --itrace option. -- 2.21.1