From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.12]) (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 47F7B42317A for ; Wed, 29 Apr 2026 18:49:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.12 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777488570; cv=none; b=eO55rJehOrMjp8HmqkIxKKybsqotCMNOwzblMylrtSr8I1EkRYgCMmsuHo8el/pk0iKgqkETAhuM8YmiXzQ2xL5AJoX2Bgb9aGZ1FJCHKqpTYOIjzln76eXUZrcQ4QadyMlO0KnZE242s7EAF6wtgtdd4erMU5VEQI1Pp/+4mAw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777488570; c=relaxed/simple; bh=c/VrSfeRyK2BcOQRuAeB5sHUimURnt5DR1Uti5gcW34=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=fAdA3FWPPtVPbPTFdZVOaStXm7CoHvCM8lMhjxE+a0up+QGxFxllBncww4LFRkfKDgBGZnaJwJXDsNtpPC/UuD305v32WYmnvRjcWlLEp5Vs/cjPLXpBd0XRjXAV7FHLv+QrWVUV3394GX1upDes4/ukcR+1KXlaa/9KHau3IAI= 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=PHTHWIC8; arc=none smtp.client-ip=198.175.65.12 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="PHTHWIC8" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1777488567; x=1809024567; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=c/VrSfeRyK2BcOQRuAeB5sHUimURnt5DR1Uti5gcW34=; b=PHTHWIC8JxSd/JrBGYdHCRJVmDH9ZxdWt35xPfDi50HxeycqBLyd4ghz /9GCqQM8l1ldbtn1G9xKd4363WyI6M4iL/7ClWs9KOFM22DIs0JCZumcb xuJPj/rTsoI1gXFxsmCfA+eVfJETk7NaOM4gBiMpC6/lmC0EEIfjNVJSn bLBdMf60ppJKHzoikP7tUhiKGky7FAUHHSO5NXsE8xgjdWXqHO/yQ0Cv9 MQRSl67npEayLbQpSoetsL6QtF5d0gSxuvjyxpe60l1F3nGMTUCueAPO+ nAI6J/PDcVT4l0T0h+HgZL5hdusNZl7n48mmchHIaiiYtPyeGWamnMYJI w==; X-CSE-ConnectionGUID: xWP5stujTzqj2nzPSMrTpw== X-CSE-MsgGUID: ui1yJ7SfRbaZQouvnLftBg== X-IronPort-AV: E=McAfee;i="6800,10657,11771"; a="89890776" X-IronPort-AV: E=Sophos;i="6.23,206,1770624000"; d="scan'208";a="89890776" Received: from orviesa003.jf.intel.com ([10.64.159.143]) by orvoesa104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Apr 2026 11:49:10 -0700 X-CSE-ConnectionGUID: MhSFXGywQWy7d0AZLeImiA== X-CSE-MsgGUID: w+v6jscRQma4D0+WlIqQEA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,206,1770624000"; d="scan'208";a="238323053" Received: from mjruhl-desk.amr.corp.intel.com (HELO agluck-desk3.home.arpa) ([10.124.222.13]) by ORVIESA003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Apr 2026 11:49:09 -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 v6 10/10] Documentation/filesystems/resctrl: Add footnote for telemetry fstab mount caveat Date: Wed, 29 Apr 2026 11:48:58 -0700 Message-ID: <20260429184858.36423-11-tony.luck@intel.com> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260429184858.36423-1-tony.luck@intel.com> References: <20260429184858.36423-1-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. -- 2.53.0