From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.16]) (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 44EE915D5D9; Wed, 9 Oct 2024 22:42:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728513764; cv=none; b=Z2Fnmg8BdOVtgE+Egd8/Cctq3VZeAo+QKiZx8HGB3LustJQPgRafPoThaL3vtxY+yJIszLstZGKijevn6PBTISi9GVKG2Lfb0tD9F38+3QDCl6IHHW3fX09OTs1fRVYTXc0/mX7Pz0FUrckzxGoLuNQ5KcRQ4EYJfmqIsWVV+b0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728513764; c=relaxed/simple; bh=M/jYqexT1hPJpZFhtuqzJvWEFeg2v79s2Hd6JNUeEzI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=eexv4f3Vnls2bC5+gbM/rpNKtul6hpTq2bsoJzy1Pkh4LKaoWxKJfHBH8xOpmzEhN6fdBktNoVrpiUnDZV2q25pDiPi8zc3J5K+214MieyqymjFPGUu+gQO0nukzEv0eDfDT/5negr/yENrIcMiGd/MRjeQ+S3pzDzQniulBFD8= 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=ZIWjNpcG; arc=none smtp.client-ip=198.175.65.16 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="ZIWjNpcG" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1728513762; x=1760049762; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=M/jYqexT1hPJpZFhtuqzJvWEFeg2v79s2Hd6JNUeEzI=; b=ZIWjNpcGZLaEaAEDOrmyV01GHNN8Y+dpS7Z98nAJHJGqt9x+ctO+K1aC SbNFHWQJ5eQksKKmkIS3fROMwjdyZmFAdJZhy+o5s0IAL0GYU5HunB0XI R38WqSraI88r+aqqhkf3jc0r2MMKDpoKJ5IE1kVpmDS5waEns2dux81Ca zQXqUbgiJ1IaqoJD+0TIbwXSvGrsNQMgBsWLJdvu2JsWXC82qXQY8Ce5F +G/35e9RYh1GSJV1QOq/CCCg+lckK8x6/czZ4QIh7lwOwuMH2JlzvzIGc uMmCo8VEnm2qAnQyZxgr2A+e+Br623S6boogGT79+p6l9zAktECVEz8iW g==; X-CSE-ConnectionGUID: CNIFzll1RlO/Eo7NzzXoCw== X-CSE-MsgGUID: 0QQaw1JmRjis2Dh2nui8Ow== X-IronPort-AV: E=McAfee;i="6700,10204,11220"; a="27931565" X-IronPort-AV: E=Sophos;i="6.11,191,1725346800"; d="scan'208";a="27931565" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by orvoesa108.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Oct 2024 15:42:36 -0700 X-CSE-ConnectionGUID: VYgdYngeSbqWRF33DTyLxA== X-CSE-MsgGUID: VFaRBY4FSYOoKihsqrBvIA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.11,191,1725346800"; d="scan'208";a="81410626" Received: from agluck-desk3.sc.intel.com ([172.25.222.70]) by orviesa004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Oct 2024 15:42:35 -0700 Date: Wed, 9 Oct 2024 15:42:33 -0700 From: Tony Luck To: Babu Moger Cc: corbet@lwn.net, fenghua.yu@intel.com, reinette.chatre@intel.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, paulmck@kernel.org, rdunlap@infradead.org, tj@kernel.org, peterz@infradead.org, yanjiewtw@gmail.com, kim.phillips@amd.com, lukas.bulwahn@gmail.com, seanjc@google.com, jmattson@google.com, leitao@debian.org, jpoimboe@kernel.org, rick.p.edgecombe@intel.com, kirill.shutemov@linux.intel.com, jithu.joseph@intel.com, kai.huang@intel.com, kan.liang@linux.intel.com, daniel.sneddon@linux.intel.com, pbonzini@redhat.com, sandipan.das@amd.com, ilpo.jarvinen@linux.intel.com, peternewman@google.com, maciej.wieczor-retman@intel.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, eranian@google.com, james.morse@arm.com Subject: Re: [PATCH v8 07/25] x86/resctrl: Introduce the interface to display monitor mode Message-ID: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Oct 09, 2024 at 12:39:32PM -0500, Babu Moger wrote: > +"mbm_assign_mode": > + Reports the list of monitoring modes supported. The enclosed brackets > + indicate which mode is enabled. > + :: > + > + cat /sys/fs/resctrl/info/L3_MON/mbm_assign_mode > + [mbm_cntr_assign] > + default > + > + "mbm_cntr_assign": > + > + In mbm_cntr_assign mode user-space is able to specify which control > + or monitor groups in resctrl should have a counter assigned using the > + 'mbm_assign_control' file. The number of counters available is described > + in the 'num_mbm_cntrs' file. Changing the mode may cause all counters on > + a resource to reset. > + > + The mode is useful on platforms which support more control and monitor > + groups than hardware counters, meaning 'unassigned' control or monitor > + groups will report 'Unavailable' or count the traffic in an unpredictable > + way. > + > + AMD Platforms with ABMC (Assignable Bandwidth Monitoring Counters) feature > + enable this mode by default so that counters remain assigned even when the > + corresponding RMID is not in use by any processor. > + > + "default": > + > + By default resctrl assumes each control and monitor group has a hardware > + counter. Hardware that does not support 'mbm_cntr_assign' mode will still > + allow more control or monitor groups than 'num_rmids' to be created. In Should that be s/num_rmids/num_mbm_cntrs/ ? -Tony