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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A2EE1C6FD1C for ; Wed, 22 Mar 2023 20:10:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231965AbjCVUK3 (ORCPT ); Wed, 22 Mar 2023 16:10:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50660 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231629AbjCVUJb (ORCPT ); Wed, 22 Mar 2023 16:09:31 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2BE4B7B3A0; Wed, 22 Mar 2023 13:02:52 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C8171622C1; Wed, 22 Mar 2023 20:02:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8019EC433EF; Wed, 22 Mar 2023 20:02:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1679515323; bh=hK+x42Q/uF3uttO6IsFrAqE3HDLQUzKmJcaBgft0unU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jAnWrP9ErldxYgsuw5GexXiNfR0kF8+WiHOqt1cdKUaZwutQTM7NHDXo3SFLZ9prA QswBjS3AJAOUrUaGanVVRCt1MjqTuRPAsKfuW9zzzDahswXteubMJKZa2bq6kvecfr nKPQhlDdMK2DHukLafBnIUiMQe29Jklhbb+mn3lfN8OwLg2yp9N1IuSaVE8hkm1nHc SWanxJvzuOogJJeXIfINPtUkN2irzU/MfyR5oS1RYdlO2jLOuh2qM3psmmGrt9USNC SqE2TBxnpCArXuxIB4lWbMMkPHJvl4KfwQ0LVj6BoNHbbdbAaUVcYJrG40Yk2QevzF nXa/GjnsBBD1g== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Prarit Bhargava , linux-pm@vger.kernel.org, Len Brown , Sasha Levin , lenb@kernel.org Subject: [PATCH AUTOSEL 5.15 14/16] tools/power turbostat: Fix /dev/cpu_dma_latency warnings Date: Wed, 22 Mar 2023 16:01:18 -0400 Message-Id: <20230322200121.1997157-14-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230322200121.1997157-1-sashal@kernel.org> References: <20230322200121.1997157-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Prarit Bhargava [ Upstream commit 40aafc7d58d3544f152a863a0e9863014b6d5d8c ] When running as non-root the following error is seen in turbostat: turbostat: fopen /dev/cpu_dma_latency : Permission denied turbostat and the man page have information on how to avoid other permission errors, so these can be fixed the same way. Provide better /dev/cpu_dma_latency warnings that provide instructions on how to avoid the error, and update the man page. Signed-off-by: Prarit Bhargava Cc: linux-pm@vger.kernel.org Signed-off-by: Len Brown Signed-off-by: Sasha Levin --- tools/power/x86/turbostat/turbostat.8 | 2 ++ tools/power/x86/turbostat/turbostat.c | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/tools/power/x86/turbostat/turbostat.8 b/tools/power/x86/turbostat/turbostat.8 index 9b17097bc3d7b..b3d4bf08e70b1 100644 --- a/tools/power/x86/turbostat/turbostat.8 +++ b/tools/power/x86/turbostat/turbostat.8 @@ -296,6 +296,8 @@ Alternatively, non-root users can be enabled to run turbostat this way: # chmod +r /dev/cpu/*/msr +# chmod +r /dev/cpu_dma_latency + .B "turbostat " reads hardware counters, but doesn't write them. So it will not interfere with the OS or other programs, including diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c index 4f176bbf29f42..84b8a35c91972 100644 --- a/tools/power/x86/turbostat/turbostat.c +++ b/tools/power/x86/turbostat/turbostat.c @@ -5237,7 +5237,7 @@ void print_dev_latency(void) retval = read(fd, (void *)&value, sizeof(int)); if (retval != sizeof(int)) { - warn("read %s\n", path); + warn("read failed %s\n", path); close(fd); return; } -- 2.39.2