From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.11]) (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 5D7F41D2B34 for ; Tue, 15 Oct 2024 23:29:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729034949; cv=none; b=Z+99Dq1JRh6QzIbyr3FeqnKZ4kt+QHpzCkjyudunQ8PFILrYwhlW0vUu7B3jhZVL9mlbp1Vap1C0rWFpyLfleZCB6Ycv9WtUKAbXJf9WmW4OK5ZgyFW2w9BTaKwDNcfkuH226ZlkHeOL3Xiq9IHUD/duLfVLVocCDuxUbEEUXxE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729034949; c=relaxed/simple; bh=oh6/s/+JCpbzRz14BY0hEXJT1wEU6TbgEQaQA6kvSmg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Gh+/gp/wqQ/IgdsM/b9kla8J4uf+oYqvOmrSNjQIf+ZUb+RpdQNdrGwzOF3QTYMEbRAzGGTN8KJyTe6QTuEF3hxMdK0gEpZIWjeuZE8TU0GpCcgv3I8uhByZiUg3dfhxfz2NUsqzNRTu8enQBlbGdSWaFltF3aFBBDtlxfoq3Mo= 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=XZk+Oo+/; arc=none smtp.client-ip=198.175.65.11 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="XZk+Oo+/" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1729034948; x=1760570948; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=oh6/s/+JCpbzRz14BY0hEXJT1wEU6TbgEQaQA6kvSmg=; b=XZk+Oo+/If9xmRZ0vMLBZ/3tTg9pWBcdky4cwRtD/dyK1GCory3bXu6w HvZlUNZZf8/64yTptoDyLbpHTINv1gIl9SD0DKy2JVGefAlt8I4A7fMyg AKQAd+edkf4BeXU21Ztot28ocNrmRAWyLyhoxGSt6itIv22VKwSgjyHns lMwknL6/Uks/XME0lfy0Am9rzOwj57fknd7i6vo4PCQRzbr+UIrEfUemT jvruvsJPyx7z4JJ3ZWF4nBr/dmssNCFB7YKlNpYn0C5zWtr7cTYNTx+IO ggHwm/U8fhMHHF+KaRrK1BDFLmNgBxJgnsF1l0FCzbYyoCC4KF8FEoR2/ w==; X-CSE-ConnectionGUID: 2PxwPuazRGylD8vhqDW8aQ== X-CSE-MsgGUID: Y7SjzXDDR2e+0MRLmL8EAg== X-IronPort-AV: E=McAfee;i="6700,10204,11222"; a="39011700" X-IronPort-AV: E=Sophos;i="6.11,199,1725346800"; d="scan'208";a="39011700" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by orvoesa103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Oct 2024 16:29:07 -0700 X-CSE-ConnectionGUID: +UE3xrSUS3K+WIYPdlTSKQ== X-CSE-MsgGUID: 9f14yDEMQReNMiuKFFfkIQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.11,206,1725346800"; d="scan'208";a="115491165" Received: from agluck-desk3.sc.intel.com ([172.25.222.70]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Oct 2024 16:29:05 -0700 Date: Tue, 15 Oct 2024 16:29:04 -0700 From: Tony Luck To: James Morse Cc: x86@kernel.org, linux-kernel@vger.kernel.org, Fenghua Yu , Reinette Chatre , Thomas Gleixner , Ingo Molnar , Borislav Petkov , H Peter Anvin , Babu Moger , shameerali.kolothum.thodi@huawei.com, D Scott Phillips OS , carl@os.amperecomputing.com, lcherian@marvell.com, bobo.shaobowang@huawei.com, tan.shaopeng@fujitsu.com, baolin.wang@linux.alibaba.com, Jamie Iles , Xin Hao , peternewman@google.com, dfustini@baylibre.com, amitsinght@marvell.com, David Hildenbrand , Rex Nie , Dave Martin , Shaopeng Tan Subject: Re: [PATCH v5 06/40] x86/resctrl: Remove data_width and the tabular format Message-ID: References: <20241004180347.19985-1-james.morse@arm.com> <20241004180347.19985-7-james.morse@arm.com> 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: <20241004180347.19985-7-james.morse@arm.com> On Fri, Oct 04, 2024 at 06:03:13PM +0000, James Morse wrote: > The resctrl architecture code provides a data_width for the controls of > each resource. This is used to zero pad all control values in the schemata > file so they appear in columns. The same is done with the resource names > to complete the visual effect. e.g. > | SMBA:0=2048 > | L3:0=00ff > > AMD platforms discover their maximum bandwidth for the MB resource from > firmware, but hard-code the data_width to 4. If the maximum bandwidth > requires more digits - the tabular format is silently broken. > If new schema are added resctrl will need to be able to determine the > maximum width. The benefit of this pretty-printing is questionable. Agreed. It's particularly non-useful for L2 resources on systems with hundred+ cores. The L2 line in schemata is very long and doesn't look "pretty" at all. Padding may make it even longer. It never worked with the mba_MBps mount option because the field width wasn't updated for prettiness. E.g. $ cat schemata MB:0=4294967295;1=4294967295 L3:0=fff;1=fff > Instead of handling runtime discovery of the data_width for AMD platforms, > remove the feature. These fields are always zero padded so should be > harmless to remove if the whole field has been treated as a number. > In the above example, this would now look like this: Huzzah! Reviewed-by: Tony Luck -Tony