Hi Brendan,
Please excuse the top posting, but I'm replying here as I'm following the section "Creating a kunitconfig" in Documentation/kunit/start.rst.
Could the three line kunitconfig file live under say arch/um/configs/kunit_defconfig?
So that it's always provided? And could even be extended with tests which people would expect to be run by default? (say in distributions)
-- Kieran
On 28/11/2018 19:36, Brendan Higgins wrote:
Add documentation for KUnit, the Linux kernel unit testing framework.
- Add intro and usage guide for KUnit
- Add API reference
Signed-off-by: Felix Guo felixguoxiuping@gmail.com Signed-off-by: Brendan Higgins brendanhiggins@google.com
Documentation/index.rst | 1 + Documentation/kunit/api/index.rst | 16 ++ Documentation/kunit/api/test.rst | 15 + Documentation/kunit/faq.rst | 46 +++ Documentation/kunit/index.rst | 80 ++++++ Documentation/kunit/start.rst | 180 ++++++++++++ Documentation/kunit/usage.rst | 447 ++++++++++++++++++++++++++++++ 7 files changed, 785 insertions(+) create mode 100644 Documentation/kunit/api/index.rst create mode 100644 Documentation/kunit/api/test.rst create mode 100644 Documentation/kunit/faq.rst create mode 100644 Documentation/kunit/index.rst create mode 100644 Documentation/kunit/start.rst create mode 100644 Documentation/kunit/usage.rst
diff --git a/Documentation/index.rst b/Documentation/index.rst index 5db7e87c7cb1d..275ef4db79f61 100644 --- a/Documentation/index.rst +++ b/Documentation/index.rst @@ -68,6 +68,7 @@ merged much easier. kernel-hacking/index trace/index maintainer/index
- kunit/index
Kernel API documentation
diff --git a/Documentation/kunit/api/index.rst b/Documentation/kunit/api/index.rst new file mode 100644 index 0000000000000..c31c530088153 --- /dev/null +++ b/Documentation/kunit/api/index.rst @@ -0,0 +1,16 @@ +.. SPDX-License-Identifier: GPL-2.0
+============= +API Reference +============= +.. toctree::
- test
+This section documents the KUnit kernel testing API. It is divided into 3 +sections:
+================================= ============================================== +:doc:`test` documents all of the standard testing API
excluding mocking or mocking related features.+================================= ============================================== diff --git a/Documentation/kunit/api/test.rst b/Documentation/kunit/api/test.rst new file mode 100644 index 0000000000000..7c926014f047c --- /dev/null +++ b/Documentation/kunit/api/test.rst @@ -0,0 +1,15 @@ +.. SPDX-License-Identifier: GPL-2.0
+======== +Test API +========
+This file documents all of the standard testing API excluding mocking or mocking +related features.
+.. kernel-doc:: include/kunit/test.h
- :internal:
+.. kernel-doc:: include/kunit/kunit-stream.h
- :internal:
diff --git a/Documentation/kunit/faq.rst b/Documentation/kunit/faq.rst new file mode 100644 index 0000000000000..cb8e4fb2257a0 --- /dev/null +++ b/Documentation/kunit/faq.rst @@ -0,0 +1,46 @@ +.. 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.
+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.
diff --git a/Documentation/kunit/index.rst b/Documentation/kunit/index.rst new file mode 100644 index 0000000000000..c6710211b647f --- /dev/null +++ b/Documentation/kunit/index.rst @@ -0,0 +1,80 @@ +.. SPDX-License-Identifier: GPL-2.0
+========================================= +KUnit - Unit Testing for the Linux Kernel +=========================================
+.. toctree::
- :maxdepth: 2
- start
- usage
- api/index
- faq
+What is KUnit? +==============
+KUnit is a lightweight unit testing and mocking framework for the Linux kernel. +These tests are able to be run locally on a developer's workstation without a VM +or special hardware.
+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, and much more.
+Get started now: :doc:`start`
+Why KUnit? +==========
+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.
+Outside of KUnit, 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 running on +the kernel; this is true for Autotest, and kselftest, disqualifying +any of them from being considered unit testing frameworks.
+KUnit addresses the problem of being able to run tests without needing a virtual +machine or actual hardware with User Mode Linux. User Mode Linux is a Linux +architecture, like ARM or x86; however, unlike other architectures it compiles +to a standalone program that can be run like any other program directly inside +of a host operating system; to be clear, it does not require any virtualization +support; it is just a regular program.
+KUnit is fast. Excluding build time, from invocation to completion KUnit can run +several dozen tests in only 10 to 20 seconds; this might not sound like a big +deal to some people, but having such fast and easy to run tests fundamentally +changes the way you go about testing and even writing code in the first place. +Linus himself said in his `git talk at Google +https://gist.github.com/lorn/1272686/revisions#diff-53c65572127855f1b003db4064a94573R874`_:
- "... a lot of people seem to think that performance is about doing the
- same thing, just doing it faster, and that is not true. That is not what
- performance is all about. If you can do something really fast, really
- well, people will start using it differently."
+In this context Linus was talking about branching and merging, +but this point also applies to testing. If your tests are slow, unreliable, are +difficult to write, and require a special setup or special hardware to run, +then you wait a lot longer to write tests, and you wait a lot longer to run +tests; this means that tests are likely to break, unlikely to test a lot of +things, and are unlikely to be rerun once they pass. If your tests are really +fast, you run them all the time, every time you make a change, and every time +someone sends you some code. Why trust that someone ran all their tests +correctly on every change when you can just run them yourself in less time than +it takes to read his / her test log?
+How do I use it? +===================
+* :doc:`start` - for new users of KUnit +* :doc:`usage` - for a more detailed explanation of KUnit features +* :doc:`api/index` - for the list of KUnit APIs used for testing
diff --git a/Documentation/kunit/start.rst b/Documentation/kunit/start.rst new file mode 100644 index 0000000000000..5cdba5091905e --- /dev/null +++ b/Documentation/kunit/start.rst @@ -0,0 +1,180 @@ +.. SPDX-License-Identifier: GPL-2.0
+=============== +Getting Started +===============
+Installing dependencies +======================= +KUnit has the same dependencies as the Linux kernel. As long as you can build +the kernel, you can run KUnit.
+KUnit Wrapper +============= +Included with KUnit is a simple Python wrapper that helps format the output to +easily use and read KUnit output. It handles building and running the kernel, as +well as formatting the output.
+The wrapper can be run with:
+.. code-block:: bash
- ./tools/testing/kunit/kunit.py
+Creating a kunitconfig +====================== +The Python script is a thin wrapper around Kbuild as such, it needs to be +configured with a ``kunitconfig`` file. This file essentially contains the +regular Kernel config, with the specific test targets as well.
+.. code-block:: bash
- git clone -b master https://kunit.googlesource.com/kunitconfig $PATH_TO_KUNITCONFIG_REPO
- cd $PATH_TO_LINUX_REPO
- ln -s $PATH_TO_KUNIT_CONFIG_REPO/kunitconfig kunitconfig
+You may want to add kunitconfig to your local gitignore.> + +Verifying KUnit Works +-------------------------
+To make sure that everything is set up correctly, simply invoke the Python +wrapper from your kernel repo:
+.. code-block:: bash
- ./tools/testing/kunit/kunit.py
+.. note::
- You may want to run ``make mrproper`` first.
+If everything worked correctly, you should see the following:
+.. code-block:: bash
- Generating .config ...
- Building KUnit Kernel ...
- Starting KUnit Kernel ...
+followed by a list of tests that are run. All of them should be passing.
+.. note::
- Because it is building a lot of sources for the first time, the ``Building
- kunit kernel`` step may take a while.
+Writing your first test +==========================
+In your kernel repo let's add some code that we can test. Create a file +``drivers/misc/example.h`` with the contents:
+.. code-block:: c
- int misc_example_add(int left, int right);
+create a file ``drivers/misc/example.c``:
+.. code-block:: c
- #include <linux/errno.h>
- #include "example.h"
- int misc_example_add(int left, int right)
- {
return left + right;- }
+Now add the following lines to ``drivers/misc/Kconfig``:
+.. code-block:: kconfig
- config MISC_EXAMPLE
bool "My example"+and the following lines to ``drivers/misc/Makefile``:
+.. code-block:: make
- obj-$(CONFIG_MISC_EXAMPLE) += example.o
+Now we are ready to write the test. The test will be in +``drivers/misc/example-test.c``:
+.. code-block:: c
- #include <kunit/test.h>
- #include "example.h"
- /* Define the test cases. */
- static void misc_example_add_test_basic(struct kunit *test)
- {
KUNIT_EXPECT_EQ(test, 1, misc_example_add(1, 0));KUNIT_EXPECT_EQ(test, 2, misc_example_add(1, 1));KUNIT_EXPECT_EQ(test, 0, misc_example_add(-1, 1));KUNIT_EXPECT_EQ(test, INT_MAX, misc_example_add(0, INT_MAX));KUNIT_EXPECT_EQ(test, -1, misc_example_add(INT_MAX, INT_MIN));- }
- static void misc_example_test_failure(struct kunit *test)
- {
KUNIT_FAIL(test, "This test never passes.");- }
- static struct kunit_case misc_example_test_cases[] = {
KUNIT_CASE(misc_example_add_test_basic),KUNIT_CASE(misc_example_test_failure),{},- };
- static struct kunit_module misc_example_test_module = {
.name = "misc-example",.test_cases = misc_example_test_cases,- };
- module_test(misc_example_test_module);
+Now add the following to ``drivers/misc/Kconfig``:
+.. code-block:: kconfig
- config MISC_EXAMPLE_TEST
bool "Test for my example"depends on MISC_EXAMPLE && KUNIT+and the following to ``drivers/misc/Makefile``:
+.. code-block:: make
- obj-$(CONFIG_MISC_EXAMPLE_TEST) += example-test.o
+Now add it to your ``kunitconfig``:
+.. code-block:: none
- CONFIG_MISC_EXAMPLE=y
- CONFIG_MISC_EXAMPLE_TEST=y
+Now you can run the test:
+.. code-block:: bash
- ./tools/testing/kunit/kunit.py
+You should see the following failure:
+.. code-block:: none
- ...
- [16:08:57] [PASSED] misc-example:misc_example_add_test_basic
- [16:08:57] [FAILED] misc-example:misc_example_test_failure
- [16:08:57] EXPECTATION FAILED at drivers/misc/example-test.c:17
- [16:08:57] This test never passes.
- ...
+Congrats! You just wrote your first KUnit test!
+Next Steps +============= +* Check out the :doc:`usage` page for a more
- in-depth explanation of KUnit.
diff --git a/Documentation/kunit/usage.rst b/Documentation/kunit/usage.rst new file mode 100644 index 0000000000000..96ef7f9a1add4 --- /dev/null +++ b/Documentation/kunit/usage.rst @@ -0,0 +1,447 @@ +.. SPDX-License-Identifier: GPL-2.0
+============= +Using KUnit +=============
+The purpose of this document is to describe what KUnit is, how it works, how it +is intended to be used, and all the concepts and terminology that are needed to +understand it. This guide assumes a working knowledge of the Linux kernel and +some basic knowledge of testing.
+For a high level introduction to KUnit, including setting up KUnit for your +project, see :doc:`start`.
+Organization of this document +=================================
+This document is organized into two main sections: Testing and Isolating +Behavior. The first covers what a unit test is and how to use KUnit to write +them. The second covers how to use KUnit to isolate code and make it possible +to unit test code that was otherwise un-unit-testable.
+Testing +==========
+What is KUnit? +------------------
+"K" is short for "kernel" so "KUnit" is the "(Linux) Kernel Unit Testing +Framework." KUnit is intended first and foremost for writing unit tests; it is +general enough that it can be used to write integration tests; however, this is +a secondary goal. KUnit has no ambition of being the only testing framework for +the kernel; for example, it does not intend to be an end-to-end testing +framework.
+What is Unit Testing? +-------------------------
+A `unit test https://martinfowler.com/bliki/UnitTest.html`_ is a test that +tests code at the smallest possible scope, a *unit* of code. In the C +programming language that's a function.
+Unit tests should be written for all the publicly exposed functions in a +compilation unit; so that is all the functions that are exported in either a +*class* (defined below) or all functions which are **not** static.
+Writing Tests +-------------
+Test Cases +~~~~~~~~~~
+The fundamental unit in KUnit is the test case. A test case is a function with +the signature ``void (*)(struct kunit *test)``. It calls a function to be tested +and then sets *expectations* for what should happen. For example:
+.. code-block:: c
- void example_test_success(struct kunit *test)
- {
- }
- void example_test_failure(struct kunit *test)
- {
KUNIT_FAIL(test, "This test never passes.");- }
+In the above example ``example_test_success`` always passes because it does +nothing; no expectations are set, so all expectations pass. On the other hand +``example_test_failure`` always fails because it calls ``KUNIT_FAIL``, which is +a special expectation that logs a message and causes the test case to fail.
+Expectations +~~~~~~~~~~~~ +An *expectation* is a way to specify that you expect a piece of code to do +something in a test. An expectation is called like a function. A test is made +by setting expectations about the behavior of a piece of code under test; when +one or more of the expectations fail, the test case fails and information about +the failure is logged. For example:
+.. code-block:: c
- void add_test_basic(struct kunit *test)
- {
KUNIT_EXPECT_EQ(test, 1, add(1, 0));KUNIT_EXPECT_EQ(test, 2, add(1, 1));- }
+In the above example ``add_test_basic`` makes a number of assertions about the +behavior of a function called ``add``; the first parameter is always of type +``struct kunit *``, which contains information about the current test context; +the second parameter, in this case, is what the value is expected to be; the +last value is what the value actually is. If ``add`` passes all of these +expectations, the test case, ``add_test_basic`` will pass; if any one of these +expectations fail, the test case will fail.
+It is important to understand that a test case *fails* when any expectation is +violated; however, the test will continue running, potentially trying other +expectations until the test case ends or is otherwise terminated. This is as +opposed to *assertions* which are discussed later.
+To learn about more expectations supported by KUnit, see :doc:`api/test`.
+.. note::
- A single test case should be pretty short, pretty easy to understand,
- focused on a single behavior.
+For example, if we wanted to properly test the add function above, we would +create additional tests cases which would each test a different property that an +add function should have like this:
+.. code-block:: c
- void add_test_basic(struct kunit *test)
- {
KUNIT_EXPECT_EQ(test, 1, add(1, 0));KUNIT_EXPECT_EQ(test, 2, add(1, 1));- }
- void add_test_negative(struct kunit *test)
- {
KUNIT_EXPECT_EQ(test, 0, add(-1, 1));- }
- void add_test_max(struct kunit *test)
- {
KUNIT_EXPECT_EQ(test, INT_MAX, add(0, INT_MAX));KUNIT_EXPECT_EQ(test, -1, add(INT_MAX, INT_MIN));- }
- void add_test_overflow(struct kunit *test)
- {
KUNIT_EXPECT_EQ(test, INT_MIN, add(INT_MAX, 1));- }
+Notice how it is immediately obvious what all the properties that we are testing +for are.
+Assertions +~~~~~~~~~~
+KUnit also has the concept of an *assertion*. An assertion is just like an +expectation except the assertion immediately terminates the test case if it is +not satisfied.
+For example:
+.. code-block:: c
- static void mock_test_do_expect_default_return(struct kunit *test)
- {
struct mock_test_context *ctx = test->priv;struct mock *mock = ctx->mock;int param0 = 5, param1 = -5;const char *two_param_types[] = {"int", "int"};const void *two_params[] = {¶m0, ¶m1};const void *ret;ret = mock->do_expect(mock,"test_printk", test_printk,two_param_types, two_params,ARRAY_SIZE(two_params));KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ret);KUNIT_EXPECT_EQ(test, -4, *((int *) ret));- }
+In this example, the method under test should return a pointer to a value, so +if the pointer returned by the method is null or an errno, we don't want to +bother continuing the test since the following expectation could crash the test +case. `ASSERT_NOT_ERR_OR_NULL(...)` allows us to bail out of the test case if +the appropriate conditions have not been satisfied to complete the test.
+Modules / Test Suites +~~~~~~~~~~~~~~~~~~~~~
+Now obviously one unit test isn't very helpful; the power comes from having +many test cases covering all of your behaviors. Consequently it is common to +have many *similar* tests; in order to reduce duplication in these closely +related tests most unit testing frameworks provide the concept of a *test +suite*, in KUnit we call it a *test module*; all it is is just a collection of +test cases for a unit of code with a set up function that gets invoked before +every test cases and then a tear down function that gets invoked after every +test case completes.
+Example:
+.. code-block:: c
- static struct kunit_case example_test_cases[] = {
KUNIT_CASE(example_test_foo),KUNIT_CASE(example_test_bar),KUNIT_CASE(example_test_baz),{},- };
- static struct kunit_module example_test_module[] = {
.name = "example",.init = example_test_init,.exit = example_test_exit,.test_cases = example_test_cases,- };
- module_test(example_test_module);
+In the above example the test suite, ``example_test_module``, would run the test +cases ``example_test_foo``, ``example_test_bar``, and ``example_test_baz``, each +would have ``example_test_init`` called immediately before it and would have +``example_test_exit`` called immediately after it. +``module_test(example_test_module)`` registers the test suite with the KUnit +test framework.
+.. note::
- A test case will only be run if it is associated with a test suite.
+For a more information on these types of things see the :doc:`api/test`.
+Isolating Behavior +==================
+The most important aspect of unit testing that other forms of testing do not +provide is the ability to limit the amount of code under test to a single unit. +In practice, this is only possible by being able to control what code gets run +when the unit under test calls a function and this is usually accomplished +through some sort of indirection where a function is exposed as part of an API +such that the definition of that function can be changed without affecting the +rest of the code base. In the kernel this primarily comes from two constructs, +classes, structs that contain function pointers that are provided by the +implementer, and architecture specific functions which have definitions selected +at compile time.
+Classes +-------
+Classes are not a construct that is built into the C programming language; +however, it is an easily derived concept. Accordingly, pretty much every project +that does not use a standardized object oriented library (like GNOME's GObject) +has their own slightly different way of doing object oriented programming; the +Linux kernel is no exception.
+The central concept in kernel object oriented programming is the class. In the +kernel, a *class* is a struct that contains function pointers. This creates a +contract between *implementers* and *users* since it forces them to use the +same function signature without having to call the function directly. In order +for it to truly be a class, the function pointers must specify that a pointer +to the class, known as a *class handle*, be one of the parameters; this makes +it possible for the member functions (also known as *methods*) to have access +to member variables (more commonly known as *fields*) allowing the same +implementation to have multiple *instances*.
+Typically a class can be *overridden* by *child classes* by embedding the +*parent class* in the child class. Then when a method provided by the child +class is called, the child implementation knows that the pointer passed to it is +of a parent contained within the child; because of this, the child can compute +the pointer to itself because the pointer to the parent is always a fixed offset +from the pointer to the child; this offset is the offset of the parent contained +in the child struct. For example:
+.. code-block:: c
- struct shape {
int (*area)(struct shape *this);- };
- struct rectangle {
struct shape parent;int length;int width;- };
- int rectangle_area(struct shape *this)
- {
struct rectangle *self = container_of(this, struct shape, parent);return self->length * self->width;- };
- void rectangle_new(struct rectangle *self, int length, int width)
- {
self->parent.area = rectangle_area;self->length = length;self->width = width;- }
+In this example (as in most kernel code) the operation of computing the pointer +to the child from the pointer to the parent is done by ``container_of``.
+Faking Classes +~~~~~~~~~~~~~~
+In order to unit test a piece of code that calls a method in a class, the +behavior of the method must be controllable, otherwise the test ceases to be a +unit test and becomes an integration test.
+A fake just provides an implementation of a piece of code that is different than +what runs in a production instance, but behaves identically from the standpoint +of the callers; this is usually done to replace a dependency that is hard to +deal with, or is slow.
+A good example for this might be implementing a fake EEPROM that just stores the +"contents" in an internal buffer. For example, let's assume we have a class that +represents an EEPROM:
+.. code-block:: c
- struct eeprom {
ssize_t (*read)(struct eeprom *this, size_t offset, char *buffer, size_t count);ssize_t (*write)(struct eeprom *this, size_t offset, const char *buffer, size_t count);- };
+And we want to test some code that buffers writes to the EEPROM:
+.. code-block:: c
- struct eeprom_buffer {
ssize_t (*write)(struct eeprom_buffer *this, const char *buffer, size_t count);int flush(struct eeprom_buffer *this);size_t flush_count; /* Flushes when buffer exceeds flush_count. */- };
- struct eeprom_buffer *new_eeprom_buffer(struct eeprom *eeprom);
- void destroy_eeprom_buffer(struct eeprom *eeprom);
+We can easily test this code by *faking out* the underlying EEPROM:
+.. code-block:: c
- struct fake_eeprom {
struct eeprom parent;char contents[FAKE_EEPROM_CONTENTS_SIZE];- };
- ssize_t fake_eeprom_read(struct eeprom *parent, size_t offset, char *buffer, size_t count)
- {
struct fake_eeprom *this = container_of(parent, struct fake_eeprom, parent);count = min(count, FAKE_EEPROM_CONTENTS_SIZE - offset);memcpy(buffer, this->contents + offset, count);return count;- }
- ssize_t fake_eeprom_write(struct eeprom *this, size_t offset, const char *buffer, size_t count)
- {
struct fake_eeprom *this = container_of(parent, struct fake_eeprom, parent);count = min(count, FAKE_EEPROM_CONTENTS_SIZE - offset);memcpy(this->contents + offset, buffer, count);return count;- }
- void fake_eeprom_init(struct fake_eeprom *this)
- {
this->parent.read = fake_eeprom_read;this->parent.write = fake_eeprom_write;memset(this->contents, 0, FAKE_EEPROM_CONTENTS_SIZE);- }
+We can now use it to test ``struct eeprom_buffer``:
+.. code-block:: c
- struct eeprom_buffer_test {
struct fake_eeprom *fake_eeprom;struct eeprom_buffer *eeprom_buffer;- };
- static void eeprom_buffer_test_does_not_write_until_flush(struct kunit *test)
- {
struct eeprom_buffer_test *ctx = test->priv;struct eeprom_buffer *eeprom_buffer = ctx->eeprom_buffer;struct fake_eeprom *fake_eeprom = ctx->fake_eeprom;char buffer[] = {0xff};eeprom_buffer->flush_count = SIZE_MAX;eeprom_buffer->write(eeprom_buffer, buffer, 1);KUNIT_EXPECT_EQ(test, fake_eeprom->contents[0], 0);eeprom_buffer->write(eeprom_buffer, buffer, 1);KUNIT_EXPECT_EQ(test, fake_eeprom->contents[1], 0);eeprom_buffer->flush(eeprom_buffer);KUNIT_EXPECT_EQ(test, fake_eeprom->contents[0], 0xff);KUNIT_EXPECT_EQ(test, fake_eeprom->contents[1], 0xff);- }
- static void eeprom_buffer_test_flushes_after_flush_count_met(struct kunit *test)
- {
struct eeprom_buffer_test *ctx = test->priv;struct eeprom_buffer *eeprom_buffer = ctx->eeprom_buffer;struct fake_eeprom *fake_eeprom = ctx->fake_eeprom;char buffer[] = {0xff};eeprom_buffer->flush_count = 2;eeprom_buffer->write(eeprom_buffer, buffer, 1);KUNIT_EXPECT_EQ(test, fake_eeprom->contents[0], 0);eeprom_buffer->write(eeprom_buffer, buffer, 1);KUNIT_EXPECT_EQ(test, fake_eeprom->contents[0], 0xff);KUNIT_EXPECT_EQ(test, fake_eeprom->contents[1], 0xff);- }
- static void eeprom_buffer_test_flushes_increments_of_flush_count(struct kunit *test)
- {
struct eeprom_buffer_test *ctx = test->priv;struct eeprom_buffer *eeprom_buffer = ctx->eeprom_buffer;struct fake_eeprom *fake_eeprom = ctx->fake_eeprom;char buffer[] = {0xff, 0xff};eeprom_buffer->flush_count = 2;eeprom_buffer->write(eeprom_buffer, buffer, 1);KUNIT_EXPECT_EQ(test, fake_eeprom->contents[0], 0);eeprom_buffer->write(eeprom_buffer, buffer, 2);KUNIT_EXPECT_EQ(test, fake_eeprom->contents[0], 0xff);KUNIT_EXPECT_EQ(test, fake_eeprom->contents[1], 0xff);/* Should have only flushed the first two bytes. */KUNIT_EXPECT_EQ(test, fake_eeprom->contents[2], 0);- }
- static int eeprom_buffer_test_init(struct kunit *test)
- {
struct eeprom_buffer_test *ctx;ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL);ASSERT_NOT_ERR_OR_NULL(test, ctx);ctx->fake_eeprom = kunit_kzalloc(test, sizeof(*ctx->fake_eeprom), GFP_KERNEL);ASSERT_NOT_ERR_OR_NULL(test, ctx->fake_eeprom);ctx->eeprom_buffer = new_eeprom_buffer(&ctx->fake_eeprom->parent);ASSERT_NOT_ERR_OR_NULL(test, ctx->eeprom_buffer);test->priv = ctx;return 0;- }
- static void eeprom_buffer_test_exit(struct kunit *test)
- {
struct eeprom_buffer_test *ctx = test->priv;destroy_eeprom_buffer(ctx->eeprom_buffer);- }