From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.21]) (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 8B2A23D88F6 for ; Mon, 1 Jun 2026 19:56:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.21 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780343819; cv=none; b=j/1RCWHxzE/B19GcE5X0OqHlApQ4N/6cvW0ezzEwKdG93Aj2an+c6g0i/OJ2A83veDc7d/G6a/TXhFng9zB3BWQ7vspPGiwFfM0e3Mg9Si+GWGa9kljMFSEx5NXQehn0e135PNjnuTAXE1WuyjE2bw+BZzT9GPlLFuueX6fQQH4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780343819; c=relaxed/simple; bh=85p7ItNAhTY8AtSyHL6/wWbocxWYL2NWxuDEDMK36/E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=G1hbCsLgT+gek6Avs6qtab13POI9NGPEKtqIfVGbUdCuxvGaEvmuevr7JkSlGZ5nVL+PJNwChCgVrydqFFF86qXgYBlKFh9k5I1wnb58hg56E9TtpRakWVe41ewyxaDDJcbw3NtH81CMsX4KvQoprxjN6MQsefyqoqytiHotiIc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=B1arSZYv; arc=none smtp.client-ip=198.175.65.21 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="B1arSZYv" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1780343818; x=1811879818; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=85p7ItNAhTY8AtSyHL6/wWbocxWYL2NWxuDEDMK36/E=; b=B1arSZYvJk5RSD0erbri0RiqaGuSEYHVR4r/Hq2ldsrBKxRMwn4CV6NG C7UVvh3KyXTGP81qHZOq3aBCZx+k+woyHGa2IwEYgZLoH5c9GOpSbpmer 5rutGRAMUx/5PYGXFaF1FwLP0YzY01qkZoFeXFN8Fuq6otg1/nLzeeXsJ 3DDLUtqRWJfRj/yb5WssrD6lB9prVQgyrK/A64cdOW+P7jfAB55rrCZ23 cHEfDHwlVefjo1lbCV0ejSXT1q3mCYwoXYFI7OVsvVWMeiYQdbNubGF6n mGluAyViACGT6wx7LlQhv7i1x7gf02OVMa0Zj1g0yHsDVwa0YeeaANaJD g==; X-CSE-ConnectionGUID: u06ncHOkRtOz8jcBjzCXHg== X-CSE-MsgGUID: KhlBqLRBTaOniRtAG4rRVg== X-IronPort-AV: E=McAfee;i="6800,10657,11804"; a="81011678" X-IronPort-AV: E=Sophos;i="6.24,181,1774335600"; d="scan'208";a="81011678" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Jun 2026 12:56:46 -0700 X-CSE-ConnectionGUID: GfKAONXhTAmKb3HJzJ2L+w== X-CSE-MsgGUID: 1BMn2RaPTvKi7CaRM9536Q== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.24,181,1774335600"; d="scan'208";a="247946536" Received: from lstrano-mobl6.amr.corp.intel.com (HELO agluck-desk3.home.arpa) ([10.124.221.168]) by orviesa004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Jun 2026 12:56:45 -0700 From: Tony Luck To: Fenghua Yu , Reinette Chatre , Maciej Wieczor-Retman , Peter Newman , James Morse , Babu Moger , Drew Fustini , Dave Martin , Chen Yu , David E Box , x86@kernel.org Cc: Christoph Hellwig , linux-kernel@vger.kernel.org, patches@lists.linux.dev, Tony Luck Subject: [PATCH v7 14/14] Documentation/filesystems/resctrl: Add footnote for telemetry fstab mount caveat Date: Mon, 1 Jun 2026 12:56:32 -0700 Message-ID: <20260601195632.15876-15-tony.luck@intel.com> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260601195632.15876-1-tony.luck@intel.com> References: <20260601195632.15876-1-tony.luck@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Add a footnote to the 'If telemetry monitoring is enabled' sentence noting that because PMT driver enumerates telemetry features asynchronously, an automatic mount of resctrl from /etc/fstab at boot may occur before those features are available, resulting in them not being enabled. Assisted-by: Claude:Sonnet_4.6 Signed-off-by: Tony Luck --- Documentation/filesystems/resctrl.rst | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/Documentation/filesystems/resctrl.rst b/Documentation/filesystems/resctrl.rst index b003bed339fd..4e62b8c5e0d6 100644 --- a/Documentation/filesystems/resctrl.rst +++ b/Documentation/filesystems/resctrl.rst @@ -620,7 +620,7 @@ When monitoring is enabled all MON groups will also contain: each instance of an L3 cache. Each directory contains files for the enabled L3 events (e.g. "llc_occupancy", "mbm_total_bytes", and "mbm_local_bytes"). - If telemetry monitoring is enabled, there will be a "mon_PERF_PKG_YY" + If telemetry monitoring is enabled [#]_, there will be a "mon_PERF_PKG_YY" directory for each physical processor package. Each directory contains files for the enabled telemetry events (e.g. "core_energy". "activity", "uops_retired", etc.) @@ -659,6 +659,11 @@ When monitoring is enabled all MON groups will also contain: returned if the MBM event does not have an assigned counter in the CTRL_MON group nor in any of its associated MON groups. +.. [#] Telemetry features are enumerated asynchronously by the PMT driver. If + resctrl is automatically mounted from ``/etc/fstab`` at boot, the telemetry + features may not yet be available at mount time and will therefore not be + enabled. + "mon_hw_id": Available only with debug option. The identifier used by hardware for the monitor group. On x86 this is the RMID. -- 2.54.0