From patchwork Tue May 14 22:16:53 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brendan Higgins X-Patchwork-Id: 10943825 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 1BCCC933 for ; Tue, 14 May 2019 22:17:43 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0C3F728867 for ; Tue, 14 May 2019 22:17:43 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id F31F92896D; Tue, 14 May 2019 22:17:42 +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 603BB28867 for ; Tue, 14 May 2019 22:17:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726561AbfENWRl (ORCPT ); Tue, 14 May 2019 18:17:41 -0400 Received: from mail-yb1-f201.google.com ([209.85.219.201]:39606 "EHLO mail-yb1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726174AbfENWRk (ORCPT ); Tue, 14 May 2019 18:17:40 -0400 Received: by mail-yb1-f201.google.com with SMTP id k23so530360ybj.6 for ; Tue, 14 May 2019 15:17:39 -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=Wtv/g4YDlWnregZkMuB6vGhT6mZK0s7Z+NfaxgtLekE=; b=Q5HMOrwbJNM89YqHu+vD+8sRwSzKie4sE8pkjwQqXKbmvl8uUCrm4SpuFW4UU8JhnY XeejyhCTCS9puS98uTFx8EFmIo2ivhwCloJ/U0p1hceMXJW+JMLxh7E0E2tQeOq2UuzA uZxI0Ym2j+bs+4rerFEZdMmaFjvrOGk6StJ+TQn+bqsoaYxZ80ISDElTpKf5y0SFPk8h VcJ7yADl/NR3VI+Ila1czReqJ0pnzAfR3bA5HRbf56qnKlhiN8U8YpErBnLxR7gClHqR Qbxvzr+zfsgs5Z9UI/MeioiOkmyTPiLUIyzAE8HdShxJSC99+danDDMnvJhADTYyrN5z MBUg== 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=Wtv/g4YDlWnregZkMuB6vGhT6mZK0s7Z+NfaxgtLekE=; b=Tn6XhXrWTQpc5BBouBcZfOvvi16jCNIfUcpihncL3Wq6MWdNWLrJ3MiJ0GkPu1olMx 1BUZBFOOwbv8bT8DmvdBDU8FplbsAmwHEXoOfrQhn1rmM6o8/jY4xa66XQlSalkUfHdF 2jsM/s0O9mpP5QEii0YL9hvzmdO741MJ9G3UAIwQh/kCUU48xQ8imNlB+TkwxxWpXL9m PY/95iwEA4VpVgUPTemGWKdgG4Je5nKN8LLD1/j7fJCaXGgd9un2+hE5e31AVjd6ZRw+ gla3B0tx0vHOQEXgmEvrz1KfeQN+zoaUwfOtiw1v1CNA73am8tBVk4bCehdMukKHsVvE KPhQ== X-Gm-Message-State: APjAAAVrIKrxa9CQEYIQIxcLOekXr5qC5DlEs03cuPYURkZ9t5fbWQJl nyTjqVDvZYZnZ4R2h24U/qACa6Dk8hJCBnEi6/zIhg== X-Google-Smtp-Source: APXvYqzLw2GNR1CD/N7FU0EOf+vQnR8bF44lpYMHhbVCeioD/fNqnQCXEG9eHOkDZWuQz7kMqOBLBdCDFgs1RbGB1Bb/ig== X-Received: by 2002:a25:690d:: with SMTP id e13mr18821319ybc.178.1557872259260; Tue, 14 May 2019 15:17:39 -0700 (PDT) Date: Tue, 14 May 2019 15:16:53 -0700 Message-Id: <20190514221711.248228-1-brendanhiggins@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.21.0.1020.gf2820cf01a-goog Subject: [PATCH v4 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 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP ## TLDR A quick follow up to yesterday's revision. I got some feedback that I wanted to incorporate before anyone else read the update. For this reason, I will leave a TLDR of the biggest changes since v2. Biggest things to look out for (since v2): - KUnit core now outputs results in TAP14. - Heavily reworked tools/testing/kunit/kunit.py - Changed how parsing works. - Added testing. - Greg, Logan, you might want to re-review this. - Added documentation on how to use KUnit on non-UML kernels. You can see the docs rendered here[1]. There is still some discussion going on on the [PATCH v2 00/17] thread, but I wanted to get some of these updates out before they got too stale (and too difficult for me to keep track of). I hope no one minds. ## 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) 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[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/v5.1/v4 branch. ## Changes Since Last Version As I mentioned above, there are a significant number of updates since v2: - Converted KUnit core to print test results in TAP14 format as suggested by Greg and Frank. - Heavily reworked tools/testing/kunit/kunit.py - Changed how parsing works. - Added testing. - Added documentation on how to use KUnit on non-UML kernels. You can see the docs rendered here[1]. - Added a new set of EXPECTs and ASSERTs for pointer comparison. - Removed more function indirection as suggested by Logan. - Added a new patch that adds `kunit_try_catch_throw` to objtool's noreturn list. - Fixed a number of minorish issues pointed out by Shuah, Masahiro, and kbuild bot. Nevertheless, there are only a couple of minor updates since v3: - Added more context to the changelog on the objtool patch, as per Peter's request. - Moved all KUnit documentation under the Documentation/dev-tools/ directory as per Jonathan's suggestion. [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/v5.1/v4