From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753296AbbCaV6T (ORCPT ); Tue, 31 Mar 2015 17:58:19 -0400 Received: from lists.s-osg.org ([54.187.51.154]:56509 "EHLO lists.s-osg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751030AbbCaV6S (ORCPT ); Tue, 31 Mar 2015 17:58:18 -0400 Message-ID: <551B1878.8000105@osg.samsung.com> Date: Tue, 31 Mar 2015 15:58:16 -0600 From: Shuah Khan Organization: Samsung Open Source Group User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: Waiman Long CC: Peter Zijlstra , Ingo Molnar , linux-kernel@vger.kernel.org, Scott J Norton , Douglas Hatch , Shuah Khan Subject: Re: [PATCH] lfsr: a simple binary Galois linear feedback shift register References: <1427822889-8783-1-git-send-email-Waiman.Long@hp.com> <551AF3BD.1030800@osg.samsung.com> <551B1746.5090807@hp.com> In-Reply-To: <551B1746.5090807@hp.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/31/2015 03:53 PM, Waiman Long wrote: > On 03/31/2015 03:21 PM, Shuah Khan wrote: >> On 03/31/2015 11:28 AM, Waiman Long wrote: >>> This patch is based on the code sent out by Peter Zijstra as part >>> of his queue spinlock patch to provide a hashing function with open >>> addressing. The lfsr() function can be used to return a sequence of >>> numbers that cycle through all the bit patterns (2^n -1) of a given >>> bit width n except the value 0 in a somewhat random fashion depending >>> on the LFSR tap that is being used. >> Does this new test intended to test a new kernel feature? If so could >> you please include what it tests in the commit log. It isn't very clear >> to me what this test does? >> > > This test is for checking the correctness of the lfsr.h header file. I > will clarify that in the commit log. > >>> This code should be a standalone patch and not part of a larger >>> patch series. I have also modified and extended it and added some >>> testing code to verify the correctness of the taps that are being used. >> The above can be left out of the commit log. >> > > Sure. > >>> Signed-off-by: Waiman Long >>> --- >>> include/linux/lfsr.h | 84 >>> ++++++++++++++++++++++++++++++ >>> tools/testing/selftests/lfsr/Makefile | 11 ++++ >>> tools/testing/selftests/lfsr/test-lfsr.c | 70 >>> +++++++++++++++++++++++++ >>> 3 files changed, 165 insertions(+), 0 deletions(-) >>> create mode 100644 include/linux/lfsr.h >>> create mode 100644 tools/testing/selftests/lfsr/Makefile >>> create mode 100644 tools/testing/selftests/lfsr/test-lfsr.c >> I don't see the test added to selftests/Makefile? Is it the intent >> to leave it out of default test run and install? If this test >> is intended to be part of selftests run and install, please add >> it to selftests Makefile and also add install target support. >> You can find good examples in linux-kselftest next branch. >> Please add a .gitignore for git to ignore the binaries built. >> >> thanks, >> -- Shuah >> >> > > Yes, it is intended to be left out of the default selftest run and > install because the lfsr.h header is for kernel internal use and is not > accessible from any of the kernel syscall APIs. > Please add this to the commit log as well that it shouldn't be included in the default run and install. Also BUG_ON and BUILD_BUG_ON are used in this test. These are kernel defines, hope these are included somehow. -- Shuah -- Shuah Khan Sr. Linux Kernel Developer Open Source Innovation Group Samsung Research America (Silicon Valley) shuahkh@osg.samsung.com | (970) 217-8978