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=-10.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 9EAD1C43441 for ; Wed, 28 Nov 2018 19:37:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 65740205C9 for ; Wed, 28 Nov 2018 19:37:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="sY3yGXUB" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 65740205C9 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com 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 S1729199AbeK2Gj4 (ORCPT ); Thu, 29 Nov 2018 01:39:56 -0500 Received: from mail-qk1-f202.google.com ([209.85.222.202]:54380 "EHLO mail-qk1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725994AbeK2Gj4 (ORCPT ); Thu, 29 Nov 2018 01:39:56 -0500 Received: by mail-qk1-f202.google.com with SMTP id v74so27360514qkb.21 for ; Wed, 28 Nov 2018 11:37:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=99nVbqfKL8VgOyeZOYLd9fGPS1EwErpNGV1fQd8c1qI=; b=sY3yGXUB7UeexaSMFHiqXwQqWJc1kjASLGdzGosIcyV73/cIl5rC3ujnaaFiogt+qr 3UE0kqZrHe4N0ZtFk/g86WTYoPDbzISqGuduMrCxPQwcp5oXsOu032M3QYhSlkD2IzRM TnlBclywIp4pcV6BZG0eZh1pFbgKpOhPIVc6DS8FUrhoeCIJFCt8JEPCwtviX2ht06z/ 9+mzN2WmSwCSedYDp3xYEWab6D3TeVKlxQSvba8+nnsvOP5NYDb3usBmFA4lHcOxbI2b uFGVzNcSo+M+swI0AtqlEZDDIHixe4xlolsVlF1r81+Naprqiegt/QdNILlqOCQoHtDn JNkQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=99nVbqfKL8VgOyeZOYLd9fGPS1EwErpNGV1fQd8c1qI=; b=Cprz2kkMuj0sQzIdHotRbOEjlwosj/6ZAF1X+tEe83YGCG5rdyroBnrPyJATyyrloq LrYHgyTHCaoPKcw0JNBZuMKnojlw3iYoROZaoAiUW0NZ+Ys936Ik5p2YiwwYG5cxxCbH nuswvHGEm4RsR+yM6SjxcYU8LymWiEJ/T4H3lOXjE0d6s68Hsp9dIkddpGJOFzif2Ryx IFbW9IVCzbkDP+90nEp+JOmJS5Kl27+JB1W/WbxQZ2j0XSRqBy7qIACyw4/ZJInP/jtR RFVNNtVXfGiSLGfT3uO1nCrtboaRU8byibS8OKc2HLFU29pGgQEVyyC+M8fMm43xGBLL V0Tw== X-Gm-Message-State: AA+aEWYpmqV9qgoznVN6nyX7tI+bPGpOD09l+9I/TReZoQkPRW+eaqeg ypilpZ/IHl5nLkFMTDuy/17MbFaYOTVUrARxnGKKWA== X-Google-Smtp-Source: AFSGD/VCWycCbDmFp6Z5qNxzgmexxk1/jZS8YbUaoMOmSU6YkTfkM2zG1R/OjWIDtfLq/fQe62iAC1tOjqPaVFw87UApQA== X-Received: by 2002:ac8:7244:: with SMTP id l4mr4486112qtp.21.1543433831218; Wed, 28 Nov 2018 11:37:11 -0800 (PST) Date: Wed, 28 Nov 2018 11:36:17 -0800 Message-Id: <20181128193636.254378-1-brendanhiggins@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.20.0.rc0.387.gc7a69e6b6c-goog Subject: [RFC v3 00/19] kunit: introduce KUnit, the Linux kernel unit testing framework From: Brendan Higgins To: gregkh@linuxfoundation.org, keescook@google.com, mcgrof@kernel.org, shuah@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, frowand.list@gmail.com, knut.omang@oracle.com, Brendan Higgins Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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/ Additionally for convenience, I have applied these patches to a branch: https://kunit.googlesource.com/linux/+/kunit/rfc/4.19/v3 The repo may be cloned with: git clone https://kunit.googlesource.com/linux This patchset is on the kunit/rfc/4.19/v3 branch. ## Changes Since Last Version - Changed namespace prefix from `test_*` to `kunit_*` as requested by Shuah. - Started converting/cleaning up the device tree unittest to use KUnit. - Started adding KUnit expectations with custom messages. -- 2.20.0.rc0.387.gc7a69e6b6c-goog