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=-11.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,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 2BDF6C433FF for ; Thu, 15 Aug 2019 09:31:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 95313208C2 for ; Thu, 15 Aug 2019 09:31:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=zytor.com header.i=@zytor.com header.b="xlIim6ph" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730891AbfHOJbC (ORCPT ); Thu, 15 Aug 2019 05:31:02 -0400 Received: from terminus.zytor.com ([198.137.202.136]:47611 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726008AbfHOJbC (ORCPT ); Thu, 15 Aug 2019 05:31:02 -0400 Received: from terminus.zytor.com (localhost [127.0.0.1]) by terminus.zytor.com (8.15.2/8.15.2) with ESMTPS id x7F9SWQ62273959 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Thu, 15 Aug 2019 02:28:33 -0700 DKIM-Filter: OpenDKIM Filter v2.11.0 terminus.zytor.com x7F9SWQ62273959 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zytor.com; s=2019071901; t=1565861314; bh=ryZsENnTKlkD3MhgZfN5F/AhUx06fgs5gjf28SuFcho=; h=Date:From:Cc:Reply-To:To:Subject:From; b=xlIim6ph/XraYsvm/QQ9iMwJ8uyrMTONm41dNZr/BqgdZXgR2q8P3hzMdG8a982Jn b7cYYVr9jdEV8NvESxqDthIuBBJvnKSnc4eQTyCyKupKvlOjnyzSvDidlCRxn8uIn4 RVvcn7f85jiXemVHfWFJkQO+R7dxFBBcW9rPZwkwrwqzmsZQo4MI9NYQfYriCO2M4q 4bOEb7Dqu42csk4CBymF8tMy5P+4M32gnub/AOvoCbeywE13OQXE1MLMeqko2Bps6k FAL3UXxp+H1BCcwQoDdbkTFSzGb/cuWcEsf4M0Lyr3XcIv50ds5QGKE5lesvLAeatC M/yqgvIcPL5mg== Received: (from tipbot@localhost) by terminus.zytor.com (8.15.2/8.15.2/Submit) id x7F9SWx22273956; Thu, 15 Aug 2019 02:28:32 -0700 Date: Thu, 15 Aug 2019 02:28:32 -0700 X-Authentication-Warning: terminus.zytor.com: tipbot set sender to tipbot@zytor.com using -f From: tip-bot for Arnaldo Carvalho de Melo Message-ID: Cc: alexey.budankov@linux.intel.com, jmorris@namei.org, hpa@zytor.com, namhyung@kernel.org, suzuki.poulose@arm.com, mingo@kernel.org, ilubashe@akamai.com, tglx@linutronix.de, acme@redhat.com, mathieu.poirier@linaro.org, jolsa@kernel.org, adrian.hunter@intel.com, peterz@infradead.org, alexander.shishkin@linux.intel.com, linux-kernel@vger.kernel.org Reply-To: namhyung@kernel.org, mingo@kernel.org, suzuki.poulose@arm.com, ilubashe@akamai.com, tglx@linutronix.de, jmorris@namei.org, alexey.budankov@linux.intel.com, hpa@zytor.com, adrian.hunter@intel.com, alexander.shishkin@linux.intel.com, peterz@infradead.org, linux-kernel@vger.kernel.org, acme@redhat.com, jolsa@kernel.org, mathieu.poirier@linaro.org To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf ftrace: Improve error message about capability to use ftrace Git-Commit-ID: 73e5de70dca00344cb48e018131a4cadec0fabf0 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 73e5de70dca00344cb48e018131a4cadec0fabf0 Gitweb: https://git.kernel.org/tip/73e5de70dca00344cb48e018131a4cadec0fabf0 Author: Arnaldo Carvalho de Melo AuthorDate: Mon, 12 Aug 2019 17:27:11 -0300 Committer: Arnaldo Carvalho de Melo CommitDate: Wed, 14 Aug 2019 10:59:59 -0300 perf ftrace: Improve error message about capability to use ftrace If we link against libcap, then we can state that CAP_SYS_ADMIN is needed, if not, fallback to telling the user it needs to be root, as was before linking against libcap. Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexey Budankov Cc: Igor Lubashev Cc: James Morris Cc: Jiri Olsa Cc: Mathieu Poirier Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Suzuki Poulouse Link: https://lkml.kernel.org/n/tip-hhnbjdo8r67054of9zm2kxtl@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-ftrace.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c index 01a5bb58eb04..1367bb5046a7 100644 --- a/tools/perf/builtin-ftrace.c +++ b/tools/perf/builtin-ftrace.c @@ -284,7 +284,13 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv) }; if (!perf_cap__capable(CAP_SYS_ADMIN)) { - pr_err("ftrace only works for root!\n"); + pr_err("ftrace only works for %s!\n", +#ifdef HAVE_LIBCAP_SUPPORT + "users with the SYS_ADMIN capability" +#else + "root" +#endif + ); return -1; }