From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D1B1DC77B61 for ; Thu, 13 Apr 2023 10:13:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230514AbjDMKNe (ORCPT ); Thu, 13 Apr 2023 06:13:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58968 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230344AbjDMKNJ (ORCPT ); Thu, 13 Apr 2023 06:13:09 -0400 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 21ABB9EF5; Thu, 13 Apr 2023 03:12:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1681380755; x=1712916755; h=date:from:to:cc:subject:in-reply-to:message-id: references:mime-version; bh=/3k6r7D074PJRZk84hYx9S21xi/ERnExtP9WJloOvro=; b=KnfpTgpGWLIB714e3Eb0XZnLVpuPMd0QarydJl0hYb01okfCHH/M0EzC 9fxyhyjB/iUeeVewrc3R9M+yccDnC7n38/Mo8Vmg/TPBzqGS+3zhgnAGs se+vzx87jliZaTGc+zWxXoDMgtCE8QSlkNIKKY1QFFfXPiwmOF+TjxuS3 4rNVeazgy2nN05Vl6dT9sI7j5grsMQbgOo2M6lPYTB8KXB40W1shfKgxV MmQm4cRXWrFcl+8AeQmYgkeCLfsnoGyW6kw+ru+Zuq77VoxXihS9PRVBs R37b+cRZwUM17AwwyDuKrgsZNQExlmrEMmitD5gRZDOAtnQojMJmqrXyb w==; X-IronPort-AV: E=McAfee;i="6600,9927,10678"; a="346827758" X-IronPort-AV: E=Sophos;i="5.98,341,1673942400"; d="scan'208";a="346827758" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Apr 2023 03:12:34 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10678"; a="719785391" X-IronPort-AV: E=Sophos;i="5.98,341,1673942400"; d="scan'208";a="719785391" Received: from pkudryav-mobl1.ger.corp.intel.com ([10.252.45.220]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Apr 2023 03:12:32 -0700 Date: Thu, 13 Apr 2023 13:12:30 +0300 (EEST) From: =?ISO-8859-15?Q?Ilpo_J=E4rvinen?= To: linux-kselftest@vger.kernel.org cc: LKML , Reinette Chatre , Fenghua Yu , Shuah Khan , Shaopeng Tan Subject: Re: [PATCH 22/22] selftests/resctrl: Rewrite Cache Allocation Technology (CAT) test In-Reply-To: <20230412132122.29452-23-ilpo.jarvinen@linux.intel.com> Message-ID: <9912c0bd-f1c8-1f27-17a0-2a3d48279e75@linux.intel.com> References: <20230412132122.29452-1-ilpo.jarvinen@linux.intel.com> <20230412132122.29452-23-ilpo.jarvinen@linux.intel.com> MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="8323329-1640494227-1681380754=:1987" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --8323329-1640494227-1681380754=:1987 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT On Wed, 12 Apr 2023, Ilpo Järvinen wrote: > Rewrite the CAT test to allocated a buffer sized to half of LLC. Then > perform a sequence of tests with different LLC block sizes starting > from 1-bit CBM to half of the CBM bits. Flush the buffer before each > test and read the buffer twice. Observe the LLC misses on the second > read through the buffer. As the allocated LLC block gets larger and > larger, the LLC misses will become smaller and smaller giving a strong > signal on CAT working properly. I realized this description is now wrong way around as I at one point reversed the cache allocation mask to go from half of CBM bits to 1-bit but didn't remember to update the changelog (in case somebody ends up wondering why it doesn't match to what the code does). V2 will contain the correct way around description. -- i. --8323329-1640494227-1681380754=:1987--