mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-24 13:13:57 +08:00
6ae2bfd3df
Documentation should describe how to build kunit and tests as modules. Co-developed-by: Knut Omang <knut.omang@oracle.com> Signed-off-by: Knut Omang <knut.omang@oracle.com> Signed-off-by: Alan Maguire <alan.maguire@oracle.com> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
64 lines
3.2 KiB
ReStructuredText
64 lines
3.2 KiB
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0
|
|
|
|
==========================
|
|
Frequently Asked Questions
|
|
==========================
|
|
|
|
How is this different from Autotest, kselftest, etc?
|
|
====================================================
|
|
KUnit is a unit testing framework. Autotest, kselftest (and some others) are
|
|
not.
|
|
|
|
A `unit test <https://martinfowler.com/bliki/UnitTest.html>`_ is supposed to
|
|
test a single unit of code in isolation, hence the name. A unit test should be
|
|
the finest granularity of testing and as such should allow all possible code
|
|
paths to be tested in the code under test; this is only possible if the code
|
|
under test is very small and does not have any external dependencies outside of
|
|
the test's control like hardware.
|
|
|
|
There are no testing frameworks currently available for the kernel that do not
|
|
require installing the kernel on a test machine or in a VM and all require
|
|
tests to be written in userspace and run on the kernel under test; this is true
|
|
for Autotest, kselftest, and some others, disqualifying any of them from being
|
|
considered unit testing frameworks.
|
|
|
|
Does KUnit support running on architectures other than UML?
|
|
===========================================================
|
|
|
|
Yes, well, mostly.
|
|
|
|
For the most part, the KUnit core framework (what you use to write the tests)
|
|
can compile to any architecture; it compiles like just another part of the
|
|
kernel and runs when the kernel boots, or when built as a module, when the
|
|
module is loaded. However, there is some infrastructure,
|
|
like the KUnit Wrapper (``tools/testing/kunit/kunit.py``) that does not support
|
|
other architectures.
|
|
|
|
In short, this means that, yes, you can run KUnit on other architectures, but
|
|
it might require more work than using KUnit on UML.
|
|
|
|
For more information, see :ref:`kunit-on-non-uml`.
|
|
|
|
What is the difference between a unit test and these other kinds of tests?
|
|
==========================================================================
|
|
Most existing tests for the Linux kernel would be categorized as an integration
|
|
test, or an end-to-end test.
|
|
|
|
- A unit test is supposed to test a single unit of code in isolation, hence the
|
|
name. A unit test should be the finest granularity of testing and as such
|
|
should allow all possible code paths to be tested in the code under test; this
|
|
is only possible if the code under test is very small and does not have any
|
|
external dependencies outside of the test's control like hardware.
|
|
- An integration test tests the interaction between a minimal set of components,
|
|
usually just two or three. For example, someone might write an integration
|
|
test to test the interaction between a driver and a piece of hardware, or to
|
|
test the interaction between the userspace libraries the kernel provides and
|
|
the kernel itself; however, one of these tests would probably not test the
|
|
entire kernel along with hardware interactions and interactions with the
|
|
userspace.
|
|
- An end-to-end test usually tests the entire system from the perspective of the
|
|
code under test. For example, someone might write an end-to-end test for the
|
|
kernel by installing a production configuration of the kernel on production
|
|
hardware with a production userspace and then trying to exercise some behavior
|
|
that depends on interactions between the hardware, the kernel, and userspace.
|