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 <ojeda@kernel.org>
Reviewed-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

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 <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

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 <brendanhiggins@google.com>
Tested-by: Martin Fernandez <martin.fernandez@eclypsium.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

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 <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

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 <brendanhiggins@google.com>
Reviewed-by: Daniel Latypov <dlatypov@google.com>
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

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 <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

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 = <struct kunit_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 = <struct kunit_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 <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

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 <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Introduce KUNIT_BINARY_PTR_ASSERTION to match KUNIT_BINARY_INT_ASSERTION
and make KUNIT_EXPECT_EQ and KUNIT_EXPECT_PTREQ use these instead of
shared intermediate macros that only remove the need to type "==" or
"!=".

The current macro chain looks like:
KUNIT_EXPECT_EQ_MSG => KUNIT_BINARY_EQ_MSG_ASSERTION => KUNIT_BASE_EQ_MSG_ASSERTION => KUNIT_BASE_BINARY_ASSERTION
KUNIT_EXPECT_PTR_EQ_MSG => KUNIT_BINARY_PTR_EQ_MSG_ASSERTION => KUNIT_BASE_EQ_MSG_ASSERTION => KUNIT_BASE_BINARY_ASSERTION
<ditto for NE and ASSERT>

After this change:
KUNIT_EXPECT_EQ_MSG => KUNIT_BINARY_INT_ASSERTION => KUNIT_BASE_BINARY_ASSERTION
KUNIT_EXPECT_PTR_EQ_MSG => KUNIT_BINARY_PTR_ASSERTION => KUNIT_BASE_BINARY_ASSERTION

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Introduce a KUNIT_BINARY_INT_ASSERTION for the likes of KUNIT_EXPECT_LT.
This is analagous to KUNIT_BINARY_STR_ASSERTION.

Note: this patch leaves the EQ/NE macros untouched since those share
some intermediate macros for the pointer-based macros.

The current macro chain looks like:
KUNIT_EXPECT_LT_MSG => KUNIT_BASE_LT_MSG_ASSERTION => KUNIT_BASE_BINARY_ASSERTION
KUNIT_EXPECT_GT_MSG => KUNIT_BASE_GT_MSG_ASSERTION => KUNIT_BASE_BINARY_ASSERTION
<ditto for LE, GE, and ASSERT variants>

After this change:
KUNIT_EXPECT_LT_MSG => KUNIT_BINARY_INT_ASSERTION => KUNIT_BASE_BINARY_ASSERTION
KUNIT_EXPECT_GT_MSG => KUNIT_BINARY_INT_ASSERTION => KUNIT_BASE_BINARY_ASSERTION

I.e. we've traded all the unique intermediary macros for a single shared
KUNIT_BINARY_INT_ASSERTION. The only difference is that users of
KUNIT_BINARY_INT_ASSERTION also need to pass the operation (==, <, etc.).

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>