From patchwork Thu Apr 4 22:06:35 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brendan Higgins X-Patchwork-Id: 10886397 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 A08BE17E9 for ; Thu, 4 Apr 2019 22:10:05 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 864E328675 for ; Thu, 4 Apr 2019 22:10:05 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 74FB328AFB; Thu, 4 Apr 2019 22:10:05 +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 5430128675 for ; Thu, 4 Apr 2019 22:10:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730116AbfDDWKE (ORCPT ); Thu, 4 Apr 2019 18:10:04 -0400 Received: from mail-qk1-f201.google.com ([209.85.222.201]:41372 "EHLO mail-qk1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729924AbfDDWKD (ORCPT ); Thu, 4 Apr 2019 18:10:03 -0400 Received: by mail-qk1-f201.google.com with SMTP id x18so3427028qkf.8 for ; Thu, 04 Apr 2019 15:10:02 -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=HMuZC7YhYbbRbZR+3/mPo9a63tVIDjyvayAQ1BEezrw=; b=BOYdV3QLi21QjMDlnUKvGYABbEqanEJfcJeRsukkvZphSbuvalPGxmKl1ZwesWtGNJ TTJ8+3NFmHoU5SmVWtyZMkKu8Nyw/t+NSbDeEz3hnSewQabz9l0TOlahbUKG4mlWW+y7 E+UlRE3Dq9q0QgfZUw/dKPJIhCHc9qqFXPORwlb5KXQFkfpJrRmbLHnuf/2qz+1balrw W0KW7J/Co45M5GP60Z0dSf/SmsF0HJ5koZpxV+84qyBA97hNSw7rj5R/U+3z8Hv1l8hg uCfoyppCCi5h6KNouM/iEP8dlt2A3kMeawzxIGJ44E7EDJ0rNCnaqZhklLOMyyF1HyPk fMUA== 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=HMuZC7YhYbbRbZR+3/mPo9a63tVIDjyvayAQ1BEezrw=; b=gsHPozDHFybqxRZUyl596wv7pNKFxextSCKyWi2g5Z+BnAVTtsC82oHK8kDc/AsMdw ZRnKigQZnwzx8jG1HbFt8ed1CyRY5rKGDtizN1QpkdyWr3EXJ/TFJ/o6f6H8kap27UtD hIgN9bueoq3ynTC42H3VklUGB6sYn8cZ8fOJTvFns7rgJFneGXys2LZwA1Jv5RM1FLGP yk2174mwqLtmM8Wxoqf8zMrxfp/mVlsOmEsTvPtyuzM3Rel39cv9F6W+kmGTJWVvpJtC 92d7IaKeBldcnX8a6PTZ3RfK1cO54sZLtvrnaSsY6A7y4xhhadiJfVBhVdIOpIvPgx87 ucww== X-Gm-Message-State: APjAAAWM/AADABK93uc+IydG7nDZzYXdVVlQkCcOSOUQ5+T26A+ybsxB MUlb+vODxGx6krToJgr5vsSw1GH2pD+2F7g4FEQLCA== X-Google-Smtp-Source: APXvYqy2ky80xlMwOpOXMGTjrYk0Q3P0Z4woKg+c4LxenDRGrU/tuDoXYQsQZWjvMUl2LUV6LFTdSDNe8kgS8hF9kpSiLg== X-Received: by 2002:a0c:ea90:: with SMTP id d16mr1127285qvp.27.1554415802221; Thu, 04 Apr 2019 15:10:02 -0700 (PDT) Date: Thu, 4 Apr 2019 15:06:35 -0700 Message-Id: <20190404220652.19765-1-brendanhiggins@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.21.0.392.gf8f6787159e-goog Subject: [PATCH v1 00/17] kunit: introduce KUnit, the Linux kernel unit testing framework From: Brendan Higgins To: corbet@lwn.net, frowand.list@gmail.com, keescook@google.com, kieran.bingham@ideasonboard.com, mcgrof@kernel.org, robh@kernel.org, shuah@kernel.org, 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, dan.j.williams@intel.com, daniel@ffwll.ch, gregkh@linuxfoundation.org, jdike@addtoit.com, joel@jms.id.au, julia.lawall@lip6.fr, khilman@baylibre.com, knut.omang@oracle.com, mpe@ellerman.id.au, pmladek@suse.com, richard@nod.at, rostedt@goodmis.org, wfg@linux.intel.com, Brendan Higgins 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 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/v5.1-rc2/v1 The repo may be cloned with: git clone https://kunit.googlesource.com/linux This patchset is on the kunit/rfc/v5.1-rc2/v1 branch. ## Changes Since Last Version Last version was RFC v4. It seemed we were pretty much done with the RFC phase, so I started the numbering over again. Sorry if anyone finds that confusing. - Reduced usage of object oriented style of member functions as suggested by Frank. - Did a bunch of heavy clean up of the kunit_abort stuff as suggested by Frank and Stephen: - Biggest change was to reduce the usage of direct calls of member functions. - Added a better explanation of what abort is for and further explained the rationale for KUNIT_ASSERT_* vs. KUNIT_EXPECT_* - Dropped BUG() usage - Also moved try_catch interface to a new file since it seemed obscured by being mixed in with the code that used it. - Fixed some other minor issues pointed out by Stephen. - Updated email address of one of the contributors. - Dropped DT unittest port since it seemed like there was a lot more discussion to be had: it wasn't ready to leave the RFC phase. Instead, I added a KUnit test written by Iurii for PROC SYSCTL that was requested by Luis some time ago. For reference, RFC v4 can be found here: https://lkml.org/lkml/2019/2/14/1144