From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 826636FA1 for ; Mon, 3 Apr 2023 14:29:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0A20AC433D2; Mon, 3 Apr 2023 14:29:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1680532169; bh=reSjqyV7Vx7mxYNpwY6x0nOsVnPeCj6ePppeHMPHC5I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ceuDiVdWtbzziluzUPRstV8qphKOBDgtJXmvUZZN99Klf4ua/WA2Cm8xSulnkgla2 XyTtJUdA4kBLeWQicKWmxLbzuNN76PdWFVEaImRh+SR35cCuWcJ+Sl6u/VvkP/Hl6v iSxTjH9RfSo4rLd96pLxClopEIM25EbjL4tmVXIg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Prarit Bhargava , linux-pm@vger.kernel.org, Len Brown , Sasha Levin Subject: [PATCH 5.10 123/173] tools/power turbostat: Fix /dev/cpu_dma_latency warnings Date: Mon, 3 Apr 2023 16:08:58 +0200 Message-Id: <20230403140418.439560468@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230403140414.174516815@linuxfoundation.org> References: <20230403140414.174516815@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 f6b7e85b121ce..71e3f3a68b9df 100644 --- a/tools/power/x86/turbostat/turbostat.8 +++ b/tools/power/x86/turbostat/turbostat.8 @@ -294,6 +294,8 @@ 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 ef65f7eed1ec9..d33c9d427e573 100644 --- a/tools/power/x86/turbostat/turbostat.c +++ b/tools/power/x86/turbostat/turbostat.c @@ -5004,7 +5004,7 @@ 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