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=-1.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 429C7C46475 for ; Thu, 25 Oct 2018 17:40:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EE7EF2084A for ; Thu, 25 Oct 2018 17:40:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="bvKQ6245" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EE7EF2084A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727582AbeJZCOH (ORCPT ); Thu, 25 Oct 2018 22:14:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:42056 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727455AbeJZCOG (ORCPT ); Thu, 25 Oct 2018 22:14:06 -0400 Received: from [192.168.1.87] (c-24-9-64-241.hsd1.co.comcast.net [24.9.64.241]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F365E20848; Thu, 25 Oct 2018 17:40:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1540489220; bh=U48X9J3guf2EYSwQQlXhqVffpPp1CbXHPz9u+aBKczs=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=bvKQ6245U8SUc4OOUBqieKelFzgCQX44nlGWiTPuYhHEhGRXgrkBBNa0MlWfrFx4T Pa94CFQ9r02rXzOs3HbsLP+UWnbQd65lY0tBpLTlBK7PHTvTNh6XEGR5vLa8SbKpwf 9MUvs5tx2HP6XWqqcb0ImhRwM5Mz+PZYAhLhhsnw= Subject: Re: [RFC v2 00/14] kunit: introduce KUnit, the Linux kernel unit testing framework To: Brendan Higgins , gregkh@linuxfoundation.org, keescook@google.com, mcgrof@kernel.org Cc: joel@jms.id.au, mpe@ellerman.id.au, joe@perches.com, brakmo@fb.com, rostedt@goodmis.org, Tim.Bird@sony.com, khilman@baylibre.com, julia.lawall@lip6.fr, linux-kselftest@vger.kernel.org, kunit-dev@googlegroups.com, linux-kernel@vger.kernel.org, jdike@addtoit.com, richard@nod.at, linux-um@lists.infradead.org, daniel@ffwll.ch, dri-devel@lists.freedesktop.org, robh@kernel.org, dan.j.williams@intel.com, linux-nvdimm@lists.01.org, kieran.bingham@ideasonboard.com, Shuah Khan References: <20181023235750.103146-1-brendanhiggins@google.com> From: Shuah Khan Message-ID: <4b6eb273-8fe0-75be-dea0-fbbf17a7158c@kernel.org> Date: Thu, 25 Oct 2018 11:40:18 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20181023235750.103146-1-brendanhiggins@google.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/23/2018 05:57 PM, Brendan Higgins wrote: > This patch set proposes KUnit, a lightweight unit testing and mocking > framework for the Linux kernel. > > Unlike Autotest and kselftest, KUnit is a true unit testing framework; > it does not require installing the kernel on a test machine or in a VM > and does not require tests to be written in userspace running on a host > kernel. Additionally, KUnit is fast: From invocation to completion KUnit > can run several dozen tests in under a second. Currently, the entire > KUnit test suite for KUnit runs in under a second from the initial > invocation (build time excluded). > > KUnit is heavily inspired by JUnit, Python's unittest.mock, and > Googletest/Googlemock for C++. KUnit provides facilities for defining > unit test cases, grouping related test cases into test suites, providing > common infrastructure for running tests, mocking, spying, and much more. > > ## What's so special about unit testing? > > A unit test is supposed to test a single unit of code in isolation, > hence the name. There should be no dependencies outside the control of > the test; this means no external dependencies, which makes tests orders > of magnitudes faster. Likewise, since there are no external dependencies, > there are no hoops to jump through to run the tests. Additionally, this > makes unit tests deterministic: a failing unit test always indicates a > problem. Finally, because unit tests necessarily have finer granularity, > they are able to test all code paths easily solving the classic problem > of difficulty in exercising error handling code. > > ## Is KUnit trying to replace other testing frameworks for the kernel? > > No. Most existing tests for the Linux kernel are end-to-end tests, which > have their place. A well tested system has lots of unit tests, a > reasonable number of integration tests, and some end-to-end tests. KUnit > is just trying to address the unit test space which is currently not > being addressed. > > ## More information on KUnit > > There is a bunch of documentation near the end of this patch set that > describes how to use KUnit and best practices for writing unit tests. > For convenience I am hosting the compiled docs here: > https://google.github.io/kunit-docs/third_party/kernel/docs/ > > ## Changes Since Last Version > > - Updated patchset to apply cleanly on 4.19. > - Stripped down patchset to focus on just the core features (I dropped > mocking, spying, and the MMIO stuff for now; you can find these > patches here: https://kunit-review.googlesource.com/c/linux/+/1132), > as suggested by Rob. > - Cleaned up some of the commit messages and tweaked commit order a > bit based on suggestions. > I am a bit behind on reviewing this patch series. Just a quick note that I will start looking at these early next week. thanks, -- Shuah