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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 62FDCC0044D for ; Wed, 11 Mar 2020 21:00:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4FB3020751 for ; Wed, 11 Mar 2020 21:00:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726873AbgCKU77 (ORCPT ); Wed, 11 Mar 2020 16:59:59 -0400 Received: from mga17.intel.com ([192.55.52.151]:53956 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729354AbgCKU77 (ORCPT ); Wed, 11 Mar 2020 16:59:59 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 11 Mar 2020 13:59:59 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,542,1574150400"; d="scan'208";a="236415947" Received: from sai-dev-mach.sc.intel.com ([143.183.140.153]) by fmsmga008.fm.intel.com with ESMTP; 11 Mar 2020 13:59:58 -0700 Message-ID: <03ae9d057e4e3f2f0e7ba017e1ff0ea6253e3dc8.camel@intel.com> Subject: Re: [PATCH V1 10/13] selftests/resctrl: Change Cache Allocation Technology (CAT) test From: Sai Praneeth Prakhya To: Reinette Chatre , shuah@kernel.org, linux-kselftest@vger.kernel.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, tony.luck@intel.com, babu.moger@amd.com, james.morse@arm.com, ravi.v.shankar@intel.com, fenghua.yu@intel.com, x86@kernel.org, linux-kernel@vger.kernel.org Date: Wed, 11 Mar 2020 13:55:12 -0700 In-Reply-To: References: <51d0f3c928fbc310c85bac6de20745f69cbc423e.1583657204.git.sai.praneeth.prakhya@intel.com> <4ac6fd87-1393-f247-40ae-5d6e34403e0f@intel.com> <8645c93547ae6c4e35633dbb09d9355219d9e3b2.camel@intel.com> <38e679141c12108749a402fa60ef1810ef054bc8.camel@intel.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.30.5-0ubuntu0.18.10.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Hi Reinette, On Wed, 2020-03-11 at 13:22 -0700, Reinette Chatre wrote: > Hi Sai, > > On 3/11/2020 12:14 PM, Sai Praneeth Prakhya wrote: > > On Wed, 2020-03-11 at 10:03 -0700, Reinette Chatre wrote: > > > On 3/10/2020 6:59 PM, Sai Praneeth Prakhya wrote: > > > > On Tue, 2020-03-10 at 15:14 -0700, Reinette Chatre wrote: > > > > > Hi Sai, > > > > > [SNIP] > > > > Please let me know if you think otherwise > > > > > > I think this patch can be split up into logical changes without breaking > > > the tests along the way. In my original review I identified two changes > > > that can be split out. Other things that can be split out: > > > - have CAT test take shareable bits into account > > > - enable measurement of cache references (addition of this new perf > > > event attribute, hooks to get measurements, etc.) > > > - transition CAT test to use "perf rate" measurement instead of "perf > > > count" > > > - etc. > > > > I think we could split the patch like this but I am unable to see the > > benefit > > of doing so.. (Sorry! if I misunderstood what you meant). > > Separating patches into logical changes facilitates review. Please > consider this huge patch from the reviewer's perspective - it consists > out of many different changes and is hard to review. If instead this > patch was split into logical changes it would make it easier to > understand what it is trying to do/change. Ok.. makes sense. > This is not a request that I invent but part of the established kernel > development process. Please see > Documentation/process/submitting-patches.rst (section is titled "Separate > your changes"). Sure! will take a look at it. > > > As CAT and CQM test cases are buggy (CAT is not testing CAT at all) and we > > are > > not attempting to fix them by incremental changes but completely changing > > the > > test plan itself (i.e. the way the test works), so why not just remove > > older > > test cases and add new test? I thought this might be more easier for > > review > > i.e. to see the new test case all at once. Don't you think so? > > From what I understand the new test continues to use many parts of the > original test. Completely removing the original test would thus end up > needing to add back a lot of code that was removed. Incremental changes > do seem appropriate to me. The logical changes I listed above actually > has nothing to do with "the way the test works". When those building > blocks are in place the test can be changed in one patch and it would be > much more obvious how the new test is different from the original. Ok.. makes sense. Will split the patch as you suggested. Regards, Sai