linux-toradex.git/include/kunit, branch v5.19-rc7

kunit: take `kunit_assert` as `const`

2022-05-16T19:23:00+00:00

The `kunit_do_failed_assertion` function passes its
`struct kunit_assert` argument to `kunit_fail`. This one,
in turn, calls its `format` field passing the assert again
as a `const` pointer.

Therefore, the whole chain may be made `const`.

Signed-off-by: Miguel Ojeda 
Reviewed-by: Daniel Latypov 
Reviewed-by: Kees Cook 
Signed-off-by: Shuah Khan

kunit: Rework kunit_resource allocation policy

2022-05-12T17:14:39+00:00

KUnit's test-managed resources can be created in two ways:
- Using the kunit_add_resource() family of functions, which accept a
  struct kunit_resource pointer, typically allocated statically or on
  the stack during the test.
- Using the kunit_alloc_resource() family of functions, which allocate a
  struct kunit_resource using kzalloc() behind the scenes.

Both of these families of functions accept a 'free' function to be
called when the resource is finally disposed of.

At present, KUnit will kfree() the resource if this 'free' function is
specified, and will not if it is NULL. However, this can lead
kunit_alloc_resource() to leak memory (if no 'free' function is passed
in), or kunit_add_resource() to incorrectly kfree() memory which was
allocated by some other means (on the stack, as part of a larger
allocation, etc), if a 'free' function is provided.

Instead, always kfree() if the resource was allocated with
kunit_alloc_resource(), and never kfree() if it was passed into
kunit_add_resource() by the user. (If the user of kunit_add_resource()
wishes the resource be kfree()ed, they can call kfree() on the resource
from within the 'free' function.

This is implemented by adding a 'should_free' member to
struct kunit_resource and setting it appropriately. To facilitate this,
the various resource add/alloc functions have been refactored somewhat,
making them all call a __kunit_add_resource() helper after setting the
'should_free' member appropriately. In the process, all other functions
have been made static inline functions.

Signed-off-by: David Gow 
Tested-by: Daniel Latypov 
Reviewed-by: Brendan Higgins 
Signed-off-by: Shuah Khan

kunit: add ability to specify suite-level init and exit functions

2022-05-02T18:35:51+00:00

KUnit has support for setup/cleanup logic for each test case in a suite.
But it lacks the ability to specify setup/cleanup for the entire suite
itself.

This can be used to do setup that is too expensive or cumbersome to do
for each test.
Or it can be used to do simpler things like log debug information after
the suite completes.
It's a fairly common feature, so the lack of it is noticeable.

Some examples in other frameworks and languages:
* https://docs.python.org/3/library/unittest.html#setupclass-and-teardownclass
* https://google.github.io/googletest/reference/testing.html#Test::SetUpTestSuite

Meta:
This is very similar to this patch here: https://lore.kernel.org/linux-kselftest/20210805043503.20252-3-bvanassche@acm.org/
The changes from that patch:
* pass in `struct kunit *` so users can do stuff like
  `kunit_info(suite, "debug message")`
* makes sure the init failure is bubbled up as a failure
* updates kunit-example-test.c to use a suite init
* Updates kunit/usage.rst to mention the new support
* some minor cosmetic things
  * use `suite_{init,exit}` instead of `{init/exit}_suite`
  * make suite init error message more consistent w/ test init
  * etc.

Signed-off-by: Daniel Latypov 
Reviewed-by: David Gow 
Reviewed-by: Brendan Higgins 
Signed-off-by: Shuah Khan

kunit: add support for kunit_suites that reference init code

2022-04-27T00:08:25+00:00

Add support for a new kind of kunit_suite registration macro called
kunit_test_init_section_suite(); this new registration macro allows the
registration of kunit_suites that reference functions marked __init and
data marked __initdata.

Signed-off-by: Brendan Higgins 
Tested-by: Martin Fernandez 
Reviewed-by: Kees Cook 
Reviewed-by: David Gow 
Signed-off-by: Shuah Khan

kunit: split resource API from test.h into new resource.h

2022-04-04T22:23:08+00:00

Background:
Currently, a reader looking at kunit/test.h will find the file is quite
long, and the first meaty comment is a doc comment about struct
kunit_resource.

Most users will not ever use the KUnit resource API directly.
They'll use kunit_kmalloc() and friends, or decide it's simpler to do
cleanups via labels (it often can be) instead of figuring out how to use
the API.

It's also logically separate from everything else in test.h.
Removing it from the file doesn't cause any compilation errors (since
struct kunit has `struct list_head resources` to store them).

This commit:
Let's move it into a kunit/resource.h file and give it a separate page
in the docs, kunit/api/resource.rst.

We include resource.h at the bottom of test.h since
* don't want to force existing users to add a new include if they use the API
* it accesses `lock` inside `struct kunit` in a inline func
  * so we can't just forward declare, and the alternatives require
    uninlining the func, adding hepers to lock/unlock, or other more
    invasive changes.

Now the first big comment in test.h is about kunit_case, which is a lot
more relevant to what a new user wants to know.

A side effect of this is git blame won't properly track history by
default, users need to run
$ git blame -L ,1 -C17 include/kunit/resource.h

Signed-off-by: Daniel Latypov 
Reviewed-by: David Gow 
Reviewed-by: Brendan Higgins 
Signed-off-by: Shuah Khan

kunit: Introduce _NULL and _NOT_NULL macros

2022-04-04T20:29:02+00:00

Today, when we want to check if a pointer is NULL and not ERR we have
two options:

KUNIT_EXPECT_TRUE(test, ptr == NULL);

or

KUNIT_EXPECT_PTR_NE(test, ptr, (struct mystruct *)NULL);

Create a new set of macros that take care of NULL checks.

Reviewed-by: Brendan Higgins 
Reviewed-by: Daniel Latypov 
Signed-off-by: Ricardo Ribalda 
Signed-off-by: Shuah Khan

kunit: cleanup assertion macro internal variables

2022-01-31T18:55:48+00:00

All the operands should be tagged `const`.
We're only assigning them to variables so that we can compare them (e.g.
check if left == right, etc.) and avoid evaluating expressions multiple
times.

There's no need for them to be mutable.

Also rename the helper variable `loc` to `__loc` like we do with
`__assertion` and `__strs` to avoid potential name collisions with user
code.

Signed-off-by: Daniel Latypov 
Reviewed-by: David Gow 
Reviewed-by: Brendan Higgins 
Signed-off-by: Shuah Khan

kunit: factor out str constants from binary assertion structs

2022-01-31T18:55:39+00:00

If the compiler doesn't optimize them away, each kunit assertion (use of
KUNIT_EXPECT_EQ, etc.) can use 88 bytes of stack space in the worst and
most common case. This has led to compiler warnings and a suggestion
from Linus to move data from the structs into static const's where
possible [1].

This builds upon [2] which did so for the base struct kunit_assert type.
That only reduced sizeof(struct kunit_binary_assert) from 88 to 64.

Given these are by far the most commonly used asserts, this patch
factors out the textual representations of the operands and comparator
into another static const, saving 16 more bytes.

In detail, KUNIT_EXPECT_EQ(test, 2 + 2, 5) yields the following struct
  (struct kunit_binary_assert) {
    .assert = ,
    .operation = "==",
    .left_text = "2 + 2",
    .left_value = 4,
    .right_text = "5",
    .right_value = 5,
  }
After this change
  static const struct kunit_binary_assert_text __text = {
    .operation = "==",
    .left_text = "2 + 2",
    .right_text = "5",
  };
  (struct kunit_binary_assert) {
    .assert = ,
    .text = &__text,
    .left_value = 4,
    .right_value = 5,
  }

This also DRYs the code a bit more since these str fields were repeated
for the string and pointer versions of kunit_binary_assert.

Note: we could name the kunit_binary_assert_text fields left/right
instead of left_text/right_text. But that would require changing the
macros a bit since they have args called "left" and "right" which would
be substituted in `.left = #left` as `.2 + 2 = \"2 + 2\"`.

[1] https://groups.google.com/g/kunit-dev/c/i3fZXgvBrfA/m/VULQg1z6BAAJ
[2] https://lore.kernel.org/linux-kselftest/20220113165931.451305-6-dlatypov@google.com/

Signed-off-by: Daniel Latypov 
Reviewed-by: David Gow 
Reviewed-by: Brendan Higgins 
Signed-off-by: Shuah Khan

kunit: consolidate KUNIT_INIT_BINARY_ASSERT_STRUCT macros

2022-01-31T18:55:33+00:00

We currently have 2 other versions of KUNIT_INIT_BINARY_ASSERT_STRUCT.
The only differences are that
* the format funcition they pass is different
* the types of left_val/right_val should be different (integral,
pointer, string).

The latter doesn't actually matter since these macros are just plumbing
them along to KUNIT_ASSERTION where they will get type checked.

So combine them all into a single KUNIT_INIT_BINARY_ASSERT_STRUCT that
now also takes the format function as a parameter.

Signed-off-by: Daniel Latypov 
Reviewed-by: David Gow 
Reviewed-by: Brendan Higgins 
Signed-off-by: Shuah Khan

kunit: remove va_format from kunit_assert

2022-01-31T18:55:27+00:00

The concern is that having a lot of redundant fields in kunit_assert can
blow up stack usage if the compiler doesn't optimize them away [1].

The comment on this field implies that it was meant to be initialized
when the expect/assert was declared, but this only happens when we run
kunit_do_failed_assertion().

We don't need to access it outside of that function, so move it out of
the struct and make it a local variable there.

This change also takes the chance to reduce the number of macros by
inlining the now simplified KUNIT_INIT_ASSERT_STRUCT() macro.

[1] https://groups.google.com/g/kunit-dev/c/i3fZXgvBrfA/m/VULQg1z6BAAJ

Signed-off-by: Daniel Latypov 
Reviewed-by: David Gow 
Reviewed-by: Brendan Higgins 
Signed-off-by: Shuah Khan