From patchwork Tue Jul 16 09:42:44 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brendan Higgins X-Patchwork-Id: 11045597 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8C2E714DB for ; Tue, 16 Jul 2019 09:43:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7A1E0285A7 for ; Tue, 16 Jul 2019 09:43:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6C42C285A9; Tue, 16 Jul 2019 09:43:11 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, USER_IN_DEF_DKIM_WL autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E55C628451 for ; Tue, 16 Jul 2019 09:43:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728334AbfGPJnK (ORCPT ); Tue, 16 Jul 2019 05:43:10 -0400 Received: from mail-vs1-f74.google.com ([209.85.217.74]:35939 "EHLO mail-vs1-f74.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728015AbfGPJnK (ORCPT ); Tue, 16 Jul 2019 05:43:10 -0400 Received: by mail-vs1-f74.google.com with SMTP id j77so4214656vsd.3 for ; Tue, 16 Jul 2019 02:43:09 -0700 (PDT) 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=pGdEsik+1M6jb/HINg07WI5yjzJ1jMxME0W4+2uDrMc=; b=eAEOpY1OH/FnKVljQodIm2gUsxEwhjJezpJfsDh5+L9jGMf2prsNq4n5iGGl8lhFcy 3GIJYBh3yNP4rG6hnKRTyj90mHYFk0BHKtIgiGVyRA9kF/uIcjPZdmXbW8ZEQW4EZ5IH SXn4qORJzI5ksZoYb5wqvx7hlnvhT2sxT5FgtaGJr+HG+NjnhSJ69g9xxveqLaNBs89a ktkggSKnDQEOXJdhLHX3eRSCy+Xqa76qSYaf55Id0NRKz4na4h3mnh2/MOGZbY4WN6E8 fCBR1frwWPhwmOtJudmJgXI/JrEuT7i8sdsJFK8HYCxGVYzU3slHOExwB171GfmM6DRJ 5ZCQ== 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=pGdEsik+1M6jb/HINg07WI5yjzJ1jMxME0W4+2uDrMc=; b=TC/S2kG5N7+IvhJsJ5wZ/rf/ABKJzpzrFnOP8TEYds3fSJwDCv6mnNxNHhtxUswqMx WQxbQwnpWbvaHdZC4ZQ3G7KVwQy7FuGAEopKCv3djByz/+PsRgdweTULFX7Ib+ATR/22 9f3pFXlpN9PoFNeoGicyH3sAz6b+PvcjZwjdy+IOeGfSEbg+AAfJml6jBk82ic0m/jDP 5Pkhk9sJXDaSAUuKDxWt8lixF9dPZYfv62OCbswpf+NzHDoQAKu9xrPI8dWpQuLbwU48 rVBR2ka21qwcW4J3SvRGU3h+S6CLu11w0Aux2FQfZQ/4i7Yd5qzWp/H3uUBULKvKEJ6W jiCA== X-Gm-Message-State: APjAAAWJFAc04WeBhChn5KE16tEuUfvNOhyWcUmqCq5nggMWIkuNA5k0 Zz8WdtCc0oY0T2XbyWFHUaog9QDYZApk95Z9KuXELQ== X-Google-Smtp-Source: APXvYqw3wlXdIHgaqyGI3Fkb5EoQvIKrYD7PYJZvCXqueiq4LTaNvNX4mlOb1gL0HCxxqPqMgE7qX6kvoBg4NaGW2/1i8w== X-Received: by 2002:a9f:230c:: with SMTP id 12mr15226541uae.85.1563270188644; Tue, 16 Jul 2019 02:43:08 -0700 (PDT) Date: Tue, 16 Jul 2019 02:42:44 -0700 Message-Id: <20190716094302.180360-1-brendanhiggins@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.22.0.510.g264f2c817a-goog Subject: [PATCH v10 00/18] kunit: introduce KUnit, the Linux kernel unit testing framework From: Brendan Higgins To: frowand.list@gmail.com, gregkh@linuxfoundation.org, jpoimboe@redhat.com, keescook@google.com, kieran.bingham@ideasonboard.com, mcgrof@kernel.org, peterz@infradead.org, robh@kernel.org, sboyd@kernel.org, shuah@kernel.org, tytso@mit.edu, yamada.masahiro@socionext.com Cc: devicetree@vger.kernel.org, dri-devel@lists.freedesktop.org, kunit-dev@googlegroups.com, linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-nvdimm@lists.01.org, linux-um@lists.infradead.org, Alexander.Levin@microsoft.com, Tim.Bird@sony.com, amir73il@gmail.com, dan.carpenter@oracle.com, daniel@ffwll.ch, jdike@addtoit.com, joel@jms.id.au, julia.lawall@lip6.fr, khilman@baylibre.com, knut.omang@oracle.com, logang@deltatee.com, mpe@ellerman.id.au, pmladek@suse.com, rdunlap@infradead.org, richard@nod.at, rientjes@google.com, rostedt@goodmis.org, wfg@linux.intel.com, Brendan Higgins , Michal Marek , Jonathan Corbet , Iurii Zaikin Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP ## TL;DR This patchset addresses comments from Stephen Boyd. Most changes are pretty minor, but this does fix a couple of bugs pointed out by Stephen. I imagine that Stephen will probably have some more comments, but I wanted to get this out for him to look at as soon as possible. ## Background 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 (however, KUnit still allows you to run tests on test machines or in VMs if you want[1]) 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 about 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[2]. Additionally for convenience, I have applied these patches to a branch[3]. The repo may be cloned with: git clone https://kunit.googlesource.com/linux This patchset is on the kunit/rfc/v5.2/v10 branch. ## Changes Since Last Version - Went back to using spinlock in `struct kunit`. Needed for resource management API. Thanks to Stephen for this change. - Fixed bug where an init failure may not be recorded as a failure in patch 01/18. - Added append method to string_stream as suggested by Stephen. - Mostly pretty minor changes after that, which mostly pertain to string_stream and kunit_stream. [1] https://google.github.io/kunit-docs/third_party/kernel/docs/usage.html#kunit-on-non-uml-architectures [2] https://google.github.io/kunit-docs/third_party/kernel/docs/ [3] https://kunit.googlesource.com/linux/+/kunit/rfc/v5.2/v10