linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH v13 00/18] kunit: introduce KUnit, the Linux kernel unit testing framework
@ 2019-08-14  5:50 Brendan Higgins
  2019-08-14  5:50 ` [PATCH v13 01/18] kunit: test: add KUnit test runner core Brendan Higgins
                   ` (19 more replies)
  0 siblings, 20 replies; 31+ messages in thread
From: Brendan Higgins @ 2019-08-14  5:50 UTC (permalink / raw)
  To: frowand.list, gregkh, jpoimboe, keescook, kieran.bingham, mcgrof,
	peterz, robh, sboyd, shuah, tytso, yamada.masahiro
  Cc: devicetree, dri-devel, kunit-dev, linux-doc, linux-fsdevel,
	linux-kbuild, linux-kernel, linux-kselftest, linux-nvdimm,
	linux-um, Alexander.Levin, Tim.Bird, amir73il, dan.carpenter,
	daniel, jdike, joel, julia.lawall, khilman, knut.omang, logang,
	mpe, pmladek, rdunlap, richard, rientjes, rostedt, wfg,
	Brendan Higgins, Bjorn Helgaas

## TL;DR

This revision addresses comments from Stephen and Bjorn Helgaas. Most
changes are pretty minor stuff that doesn't affect the API in anyway.
One significant change, however, is that I added support for freeing
kunit_resource managed resources before the test case is finished via
kunit_resource_destroy(). Additionally, Bjorn pointed out that I broke
KUnit on certain configurations (like the default one for x86, whoops).

Based on Stephen's feedback on the previous change, I think we are
pretty close. I am not expecting any significant changes from here on
out.

## 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/v5.3/v13 branch.

## Changes Since Last Version

- Added support for freeing kunit_resources (KUnit managed resources)
  via kunit_resource_destroy() as suggested by Stephen.
- Promoted WARN() after __noreturn function to BUG() in
  "[PATCH v13 09/18] kunit: test: add support for test abort" as
  suggested by Stephen.
- Dropped concept of death test since I am not actually using it yet as
  pointed out by Stephen.
- Replaced usage of warn_slowpath_fmt with WARN in kunit_do_assertion
  since warn_slowpath_fmt is not available on some build configurations,
  as pointed out by Bjorn.
- Lots of other minor changes suggested by Stephen.

[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/v5.3/v13

-- 
2.23.0.rc1.153.gdeed80330f-goog


^ permalink raw reply	[flat|nested] 31+ messages in thread

end of thread, other threads:[~2019-08-21  0:16 UTC | newest]

Thread overview: 31+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-08-14  5:50 [PATCH v13 00/18] kunit: introduce KUnit, the Linux kernel unit testing framework Brendan Higgins
2019-08-14  5:50 ` [PATCH v13 01/18] kunit: test: add KUnit test runner core Brendan Higgins
2019-08-14  5:50 ` [PATCH v13 02/18] kunit: test: add test resource management API Brendan Higgins
2019-08-14  5:50 ` [PATCH v13 03/18] kunit: test: add string_stream a std::stream like string builder Brendan Higgins
2019-08-14  7:17   ` Stephen Boyd
2019-08-14  5:50 ` [PATCH v13 04/18] kunit: test: add assertion printing library Brendan Higgins
2019-08-14  5:50 ` [PATCH v13 05/18] kunit: test: add the concept of expectations Brendan Higgins
2019-08-14  5:50 ` [PATCH v13 06/18] kbuild: enable building KUnit Brendan Higgins
2019-08-14  5:50 ` [PATCH v13 07/18] kunit: test: add initial tests Brendan Higgins
2019-08-14  5:50 ` [PATCH v13 08/18] objtool: add kunit_try_catch_throw to the noreturn list Brendan Higgins
2019-08-14  5:50 ` [PATCH v13 09/18] kunit: test: add support for test abort Brendan Higgins
2019-08-14  7:16   ` Stephen Boyd
2019-08-14  5:51 ` [PATCH v13 10/18] kunit: test: add tests for kunit " Brendan Higgins
2019-08-14  5:51 ` [PATCH v13 11/18] kunit: test: add the concept of assertions Brendan Higgins
2019-08-14  5:51 ` [PATCH v13 12/18] kunit: test: add tests for KUnit managed resources Brendan Higgins
2019-08-14  7:18   ` Stephen Boyd
2019-08-14  5:51 ` [PATCH v13 13/18] kunit: tool: add Python wrappers for running KUnit tests Brendan Higgins
2019-08-14  5:51 ` [PATCH v13 14/18] kunit: defconfig: add defconfigs for building " Brendan Higgins
2019-08-14  7:18   ` Stephen Boyd
2019-08-14  5:51 ` [PATCH v13 15/18] Documentation: kunit: add documentation for KUnit Brendan Higgins
2019-08-14  5:51 ` [PATCH v13 16/18] MAINTAINERS: add entry for KUnit the unit testing framework Brendan Higgins
2019-08-14  5:51 ` [PATCH v13 17/18] kernel/sysctl-test: Add null pointer test for sysctl.c:proc_dointvec() Brendan Higgins
2019-08-14  5:51 ` [PATCH v13 18/18] MAINTAINERS: add proc sysctl KUnit test to PROC SYSCTL section Brendan Higgins
2019-08-14 10:03 ` [PATCH v13 00/18] kunit: introduce KUnit, the Linux kernel unit testing framework Brendan Higgins
2019-08-14 17:23   ` Stephen Boyd
2019-08-20 17:24 ` shuah
2019-08-20 18:24   ` Brendan Higgins
2019-08-20 19:08     ` shuah
2019-08-20 21:26       ` Brendan Higgins
2019-08-20 23:23         ` Brendan Higgins
2019-08-21  0:15           ` shuah

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).