Commit Graph

88 Commits

Author SHA1 Message Date
David Gow 260755184c kunit: Move kunit_abort() call out of kunit_do_failed_assertion()
KUnit aborts the current thread when an assertion fails. Currently, this
is done conditionally as part of the kunit_do_failed_assertion()
function, but this hides the kunit_abort() call from the compiler
(particularly if it's in another module). This, in turn, can lead to
both suboptimal code generation (the compiler can't know if
kunit_do_failed_assertion() will return), and to static analysis tools
like smatch giving false positives.

Moving the kunit_abort() call into the macro should give the compiler
and tools a better chance at understanding what's going on. Doing so
requires exporting kunit_abort(), though it's recommended to continue to
use assertions in lieu of aborting directly.

In addition, kunit_abort() and kunit_do_failed_assertion() are renamed
to make it clear they they're intended for internal KUnit use, to:
__kunit_do_failed_assertion() and __kunit_abort()

Suggested-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: Daniel Latypov <dlatypov@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-06-01 13:04:46 -06:00
David Gow c042030aa1 kunit: Fix obsolete name in documentation headers (func->action)
The kunit_add_action() and related functions named the kunit_action_t
parameter 'func' in early drafts, which was later renamed to 'action'
However, the doc comments were not properly updated.

Fix these to avoid confusion and 'make htmldocs' warnings.

Fixes: b9dce8a1ed ("kunit: Add kunit_add_action() to defer a call until test exit")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/lkml/20230530151840.16a56460@canb.auug.org.au/
Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-06-01 13:04:40 -06:00
Michal Wajdeczko b1eaa8b2a5 kunit: Update kunit_print_ok_not_ok function
There is no need use opaque test_or_suite pointer and is_test flag
as we don't use anything from the suite struct. Always expect test
pointer and use NULL as indication that provided results are from
the suite so we can treat them differently.

Since results could be from nested tests, like parameterized tests,
add explicit level parameter to properly indent output messages and
thus allow to reuse this function from other places.

While around, remove small code duplication near skip directive.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: David Gow <davidgow@google.com>
Cc: Rae Moar <rmoar@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-05-26 08:44:09 -06:00
David Gow 57e3cded99 kunit: kmalloc_array: Use kunit_add_action()
The kunit_add_action() function is much simpler and cleaner to use that
the full KUnit resource API for simple things like the
kunit_kmalloc_array() functionality.

Replacing it allows us to get rid of a number of helper functions, and
leaves us with no uses of kunit_alloc_resource(), which has some
usability problems and is going to have its behaviour modified in an
upcoming patch.

Note that we need to use kunit_defer_trigger_all() to implement
kunit_kfree().

Reviewed-by: Benjamin Berg <benjamin.berg@intel.com>
Reviewed-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Maxime Ripard <maxime@cerno.tech>
Signed-off-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-05-25 08:53:07 -06:00
David Gow b9dce8a1ed kunit: Add kunit_add_action() to defer a call until test exit
Many uses of the KUnit resource system are intended to simply defer
calling a function until the test exits (be it due to success or
failure). The existing kunit_alloc_resource() function is often used for
this, but was awkward to use (requiring passing NULL init functions, etc),
and returned a resource without incrementing its reference count, which
-- while okay for this use-case -- could cause problems in others.

Instead, introduce a simple kunit_add_action() API: a simple function
(returning nothing, accepting a single void* argument) can be scheduled
to be called when the test exits. Deferred actions are called in the
opposite order to that which they were registered.

This mimics the devres API, devm_add_action(), and also provides
kunit_remove_action(), to cancel a deferred action, and
kunit_release_action() to trigger one early.

This is implemented as a resource under the hood, so the ordering
between resource cleanup and deferred functions is maintained.

Reviewed-by: Benjamin Berg <benjamin.berg@intel.com>
Reviewed-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Maxime Ripard <maxime@cerno.tech>
Signed-off-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-05-25 08:52:55 -06:00
David Gow cdc87bda60 Documentation: kunit: Warn that exit functions run even if init fails
KUnit's exit functions will run even if the corresponding init function
fails. It's easy, when writing an exit function, to assume the init
function succeeded, and (for example) access uninitialised memory or
dereference NULL pointers.

Note that this case exists and should be handled in the documentation.

Suggested-by: Benjamin Berg <benjamin@sipsolutions.net>
Link: https://lore.kernel.org/linux-kselftest/a39af0400abedb2e9b31d84c37551cecc3eed0e1.camel@sipsolutions.net/
Reviewed-by: Sadiya Kazi <sadiyakazi@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-05-11 18:17:35 -06:00
Heiko Carstens 7232282dd4 kunit: increase KUNIT_LOG_SIZE to 2048 bytes
The s390 specific test_unwind kunit test has 39 parameterized tests. The
results in debugfs are truncated since the full log doesn't fit into 1500
bytes.
Therefore increase KUNIT_LOG_SIZE to 2048 bytes in a similar way like it
was done recently with commit "kunit: fix bug in debugfs logs of
parameterized tests". With that the whole test result is present.

Reported-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Rae Moar <rmoar@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-03-29 18:55:41 -06:00
Stephen Boyd 99be658811 kunit: Use gfp in kunit_alloc_resource() kernel-doc
Copy/pasting the code from the kernel-doc here doesn't compile because
kunit_alloc_resource() takes a gfp flags argument. Pass the gfp
argument from the caller to complete the example.

Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-03-17 12:28:40 -06:00
Rae Moar 2c6a96dad5 kunit: fix bug of extra newline characters in debugfs logs
Fix bug of the extra newline characters in debugfs logs. When a
line is added to debugfs with a newline character at the end,
an extra line appears in the debugfs log.

This is due to a discrepancy between how the lines are printed and how they
are added to the logs. Remove this discrepancy by checking if a newline
character is present before adding a newline character. This should closely
match the printk behavior.

Add kunit_log_newline_test to provide test coverage for this issue.  (Also,
move kunit_log_test above suite definition to remove the unnecessary
declaration prior to the suite definition)

As an example, say we add these two lines to the log:

kunit_log(..., "KTAP version 1\n");
kunit_log(..., "1..1");

The debugfs log before this fix:

 KTAP version 1

 1..1

The debugfs log after this fix:

 KTAP version 1
 1..1

Signed-off-by: Rae Moar <rmoar@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-03-10 13:59:43 -07:00
Rae Moar 887d85a073 kunit: fix bug in debugfs logs of parameterized tests
Fix bug in debugfs logs that causes individual parameterized results to not
appear because the log is reinitialized (cleared) when each parameter is
run.

Ensure these results appear in the debugfs logs, increase log size to
allow for the size of parameterized results. As a result, append lines to
the log directly rather than using an intermediate variable that can cause
stack size warnings due to the increased log size.

Here is the debugfs log of ext4_inode_test which uses parameterized tests
before the fix:

     KTAP version 1

     # Subtest: ext4_inode_test
     1..1
 # Totals: pass:16 fail:0 skip:0 total:16
 ok 1 ext4_inode_test

As you can see, this log does not include any of the individual
parametrized results.

After (in combination with the next two fixes to remove extra empty line
and ensure KTAP valid format):

 KTAP version 1
 1..1
     KTAP version 1
     # Subtest: ext4_inode_test
     1..1
        KTAP version 1
         # Subtest: inode_test_xtimestamp_decoding
         ok 1 1901-12-13 Lower bound of 32bit < 0 timestamp, no extra bits
         ... (the rest of the individual parameterized tests)
         ok 16 2446-05-10 Upper bound of 32bit >=0 timestamp. All extra
     # inode_test_xtimestamp_decoding: pass:16 fail:0 skip:0 total:16
     ok 1 inode_test_xtimestamp_decoding
 # Totals: pass:16 fail:0 skip:0 total:16
 ok 1 ext4_inode_test

Signed-off-by: Rae Moar <rmoar@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-03-10 13:59:32 -07:00
David Gow e047c5eaa7 kunit: Expose 'static stub' API to redirect functions
Add a simple way of redirecting calls to functions by including a
special prologue in the "real" function which checks to see if the
replacement function should be called (and, if so, calls it).

To redirect calls to a function, make the first (non-declaration) line
of the function:

	KUNIT_STATIC_STUB_REDIRECT(function_name, [function arguments]);

(This will compile away to nothing if KUnit is not enabled, otherwise it
will check if a redirection is active, call the replacement function,
and return. This check is protected by a static branch, so has very
little overhead when there are no KUnit tests running.)

Calls to the real function can be redirected to a replacement using:

	kunit_activate_static_stub(test, real_fn, replacement_fn);

The redirection will only affect calls made from within the kthread of
the current test, and will be automatically disabled when the test
completes. It can also be manually disabled with
kunit_deactivate_static_stub().

The 'example' KUnit test suite has a more complete example.

Co-developed-by: Daniel Latypov <dlatypov@google.com>
Signed-off-by: Daniel Latypov <dlatypov@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-02-08 14:28:17 -07:00
David Gow 7170b7ed6a kunit: Add "hooks" to call into KUnit when it's built as a module
KUnit has several macros and functions intended for use from non-test
code. These hooks, currently the kunit_get_current_test() and
kunit_fail_current_test() macros, didn't work when CONFIG_KUNIT=m.

In order to support this case, the required functions and static data
need to be available unconditionally, even when KUnit itself is not
built-in. The new 'hooks.c' file is therefore always included, and has
both the static key required for kunit_get_current_test(), and a table
of function pointers in struct kunit_hooks_table. This is filled in with
the real implementations by kunit_install_hooks(), which is kept in
hooks-impl.h and called when the kunit module is loaded.

This can  be extended for future features which require similar
"hook" behaviour, such as static stubs, by simply adding new entries to
the struct, and the appropriate code to set them.

Fixed white-space errors during commit:
Shuah Khan <skhan@linuxfoundation.org>

Resolved merge conflicts with:
db105c37a4 ("kunit: Export kunit_running()")
This patch supersedes the above.
Shuah Khan <skhan@linuxfoundation.org>

Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Rae Moar <rmoar@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-02-08 14:26:25 -07:00
Brendan Higgins 254c71374a kunit: fix kunit_test_init_section_suites(...)
Looks like kunit_test_init_section_suites(...) was messed up in a merge
conflict. This fixes it.

kunit_test_init_section_suites(...) was not updated to avoid the extra
level of indirection when .kunit_test_suites was flattened. Given no-one
was actively using it, this went unnoticed for a long period of time.

Fixes: e5857d396f ("kunit: flatten kunit_suite*** to kunit_suite** in .kunit_test_suites")
Signed-off-by: Brendan Higgins <brendan.higgins@linux.dev>
Signed-off-by: David Gow <davidgow@google.com>
Tested-by: Martin Fernandez <martin.fernandez@eclypsium.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-01-31 09:10:38 -07:00
Rae Moar dd2f0a0a2f kunit: fix bug in KUNIT_EXPECT_MEMEQ
In KUNIT_EXPECT_MEMEQ and KUNIT_EXPECT_MEMNEQ, add check if one of the
inputs is NULL and fail if this is the case.

Currently, the kernel crashes if one of the inputs is NULL. Instead,
fail the test and add an appropriate error message.

Fixes: b8a926bea8 ("kunit: Introduce KUNIT_EXPECT_MEMEQ and KUNIT_EXPECT_MEMNEQ macros")

This was found by the kernel test robot:
https://lore.kernel.org/all/202212191448.D6EDPdOh-lkp@intel.com/

Reported-by: kernel test robot <lkp@intel.com>

Signed-off-by: Rae Moar <rmoar@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-01-30 14:46:46 -07:00
Rae Moar 9c988fae6f kunit: add macro to allow conditionally exposing static symbols to tests
Create two macros:

VISIBLE_IF_KUNIT - A macro that sets symbols to be static if CONFIG_KUNIT
is not enabled. Otherwise if CONFIG_KUNIT is enabled there is no change to
the symbol definition.

EXPORT_SYMBOL_IF_KUNIT(symbol) - Exports symbol into
EXPORTED_FOR_KUNIT_TESTING namespace only if CONFIG_KUNIT is enabled. Must
use MODULE_IMPORT_NS(EXPORTED_FOR_KUNIT_TESTING) in test file in order to
use symbols.

Signed-off-by: Rae Moar <rmoar@google.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-12-12 14:13:48 -07:00
David Gow 91e9359221 kunit: Use the static key when retrieving the current test
In order to detect if a KUnit test is running, and to access its
context, the 'kunit_test' member of the current task_struct is used.
Usually, this is accessed directly or via the kunit_fail_current_task()
function.

In order to speed up the case where no test is running, add a wrapper,
kunit_get_current_test(), which uses the static key to fail early.
Equally, Speed up kunit_fail_current_test() by using the static key.

This should make it convenient for code to call this
unconditionally in fakes or error paths, without worrying that this will
slow the code down significantly.

If CONFIG_KUNIT=n (or m), this compiles away to nothing. If
CONFIG_KUNIT=y, it will compile down to a NOP (on most architectures) if
no KUnit test is currently running.

Note that kunit_get_current_test() does not work if KUnit is built as a
module. This mirrors the existing restriction on kunit_fail_current_test().

Note that the definition of kunit_fail_current_test() still wraps an
empty, inline function if KUnit is not built-in. This is to ensure that
the printf format string __attribute__ will still work.

Also update the documentation to suggest users use the new
kunit_get_current_test() function, update the example, and to describe
the behaviour when KUnit is disabled better.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Sadiya Kazi <sadiyakazi@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Daniel Latypov <dlatypov@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-12-12 14:13:47 -07:00
David Gow 908d0c177b kunit: Provide a static key to check if KUnit is actively running tests
KUnit does a few expensive things when enabled. This hasn't been a
problem because KUnit was only enabled on test kernels, but with a few
people enabling (but not _using_) KUnit on production systems, we need a
runtime way of handling this.

Provide a 'kunit_running' static key (defaulting to false), which allows
us to hide any KUnit code behind a static branch. This should reduce the
performance impact (on other code) of having KUnit enabled to a single
NOP when no tests are running.

Note that, while it looks unintuitive, tests always run entirely within
__kunit_test_suites_init(), so it's safe to decrement the static key at
the end of this function, rather than in __kunit_test_suites_exit(),
which is only there to clean up results in debugfs.

Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Daniel Latypov <dlatypov@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-12-12 14:13:47 -07:00
Daniel Latypov 34c68f432c kunit: remove KUNIT_INIT_MEM_ASSERTION macro
Commit 870f63b7cd78 ("kunit: eliminate KUNIT_INIT_*_ASSERT_STRUCT
macros") removed all the other macros of this type.

But it raced with commit b8a926bea8 ("kunit: Introduce
KUNIT_EXPECT_MEMEQ and KUNIT_EXPECT_MEMNEQ macros"), which added another
instance.

Remove KUNIT_INIT_MEM_ASSERTION and just use the generic
KUNIT_INIT_ASSERT macro instead.
Rename the `size` arg to avoid conflicts by appending a "_" (like we did
in the previous commit).

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-12-12 14:13:47 -07:00
Daniel Latypov 697365c086 kunit: eliminate KUNIT_INIT_*_ASSERT_STRUCT macros
These macros exist because passing an initializer list to other macros
is hard.

The goal of these macros is to generate a line like
  struct $ASSERT_TYPE __assertion = $APPROPRIATE_INITIALIZER;
e.g.
  struct kunit_unary_assertion __assertion = {
	  .condition = "foo()",
	  .expected_true = true
  };

But the challenge is you can't pass `{.condition=..., .expect_true=...}`
as a macro argument, since the comma means you're actually passing two
arguments, `{.condition=...` and `.expect_true=....}`.
So we'd made custom macros for each different initializer-list shape.

But we can work around this with the following generic macro
  #define KUNIT_INIT_ASSERT(initializers...) { initializers }

Note: this has the downside that we have to rename some macros arguments
to not conflict with the struct field names (e.g. `expected_true`).
It's a bit gross, but probably worth reducing the # of macros.

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-12-12 14:13:47 -07:00
Maíra Canal b8a926bea8 kunit: Introduce KUNIT_EXPECT_MEMEQ and KUNIT_EXPECT_MEMNEQ macros
Currently, in order to compare memory blocks in KUnit, the KUNIT_EXPECT_EQ
or KUNIT_EXPECT_FALSE macros are used in conjunction with the memcmp
function, such as:
    KUNIT_EXPECT_EQ(test, memcmp(foo, bar, size), 0);

Although this usage produces correct results for the test cases, when
the expectation fails, the error message is not very helpful,
indicating only the return of the memcmp function.

Therefore, create a new set of macros KUNIT_EXPECT_MEMEQ and
KUNIT_EXPECT_MEMNEQ that compare memory blocks until a specified size.
In case of expectation failure, those macros print the hex dump of the
memory blocks, making it easier to debug test failures for memory blocks.

That said, the expectation

    KUNIT_EXPECT_EQ(test, memcmp(foo, bar, size), 0);

would translate to the expectation

    KUNIT_EXPECT_MEMEQ(test, foo, bar, size);

Signed-off-by: Maíra Canal <mairacanal@riseup.net>
Reviewed-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-10-27 02:39:47 -06:00
Daniel Latypov c1144e0106 kunit: declare kunit_assert structs as const
Everywhere we use the assert structs now takes them via const*, as of
commit 7466886b40 ("kunit: take `kunit_assert` as `const`").

So now let's properly declare the structs as const as well.

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-10-07 10:19:18 -06:00
Daniel Latypov 97d453bc40 kunit: rename base KUNIT_ASSERTION macro to _KUNIT_FAILED
Context:
Currently this macro's name, KUNIT_ASSERTION conflicts with the name of
an enum whose values are {KUNIT_EXPECTATION, KUNIT_ASSERTION}.

It's hard to think of a better name for the enum, so rename this macro.
It's also a bit strange that the macro might do nothing depending on the
boolean argument `pass`. Why not have callers check themselves?

This patch:
Moves the pass/fail checking into the callers of KUNIT_ASSERTION, so now
we only call it when the check has failed.
Then we rename the macro the _KUNIT_FAILED() to reflect the new
semantics.

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-10-07 10:16:45 -06:00
Daniel Latypov a8495ad8e9 kunit: remove format func from struct kunit_assert, get it to 0 bytes
Each calll to a KUNIT_EXPECT_*() macro creates a local variable which
contains a struct kunit_assert.

Normally, we'd hope the compiler would be able to optimize this away,
but we've seen cases where it hasn't, see
https://groups.google.com/g/kunit-dev/c/i3fZXgvBrfA/m/GbrMNej2BAAJ.

In changes like commit 21957f90b2 ("kunit: split out part of
kunit_assert into a static const"), we've moved more and more parts out
of struct kunit_assert and its children types (kunit_binary_assert).

This patch removes the final field and gets us to:
  sizeof(struct kunit_assert) == 0
  sizeof(struct kunit_binary_assert) == 24 (on UML x86_64).

This also reduces the amount of macro plumbing going on at the cost of
passing in one more arg to the base KUNIT_ASSERTION macro and
kunit_do_failed_assertion().

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-10-07 10:16:38 -06:00
Daniel Latypov 047a8a0a2d kunit: make kunit_kfree() only work on pointers from kunit_malloc() and friends
kunit_kfree() exists to clean up allocations from kunit_kmalloc() and
friends early instead of waiting for this to happen automatically at the
end of the test.

But it can be used on *anything* registered with the kunit resource API.

E.g. the last 2 statements are equivalent:
  struct kunit_resource *res = something();
  kfree(res->data);
  kunit_put_resource(res);

The problem is that there could be multiple resources that point to the
same `data`.

E.g. you can have a named resource acting as a pseudo-global variable in
a test. If you point it to data allocated with kunit_kmalloc(), then
calling `kunit_kfree(ptr)` has the chance to delete either the named
resource or to kfree `ptr`.
Which one it does depends on the order the resources are registered as
kunit_kfree() will delete resources in LIFO order.

So this patch restricts kunit_kfree() to only working on resources
created by kunit_kmalloc(). Calling it is therefore guaranteed to free
the memory, not do anything else.

Note: kunit_resource_instance_match() wasn't used outside of KUnit, so
it should be safe to remove from the public interface. It's also
generally dangerous, as shown above, and shouldn't be used.

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>
2022-10-07 10:15:44 -06:00
Joe Fradley 7d97635b72 kunit: no longer call module_info(test, "Y") for kunit modules
Because KUnit test execution is not a guarantee with the kunit.enable
parameter we want to be careful to only taint the kernel when actual
tests run. Calling module_info(test, "Y") for every KUnit module
automatically causes the kernel to be tainted upon module load. Therefore,
we're removing this call and relying on the KUnit framework to taint the
kernel or not.

Signed-off-by: Joe Fradley <joefradley@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-09-30 13:17:49 -06:00
Joe Fradley d20a6ba5e3 kunit: add kunit.enable to enable/disable KUnit test
This patch adds the kunit.enable module parameter that will need to be
set to true in addition to KUNIT being enabled for KUnit tests to run.
The default value is true giving backwards compatibility. However, for
the production+testing use case the new config option
KUNIT_DEFAULT_ENABLED can be set to N requiring the tester to opt-in
by passing kunit.enable=1 to the kernel.

Signed-off-by: Joe Fradley <joefradley@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-09-30 13:17:39 -06:00
Sander Vanheule aded3cad90 kunit: fix assert_type for comparison macros
When replacing KUNIT_BINARY_*_MSG_ASSERTION() macros with
KUNIT_BINARY_INT_ASSERTION(), the assert_type parameter was not always
correctly transferred.  Specifically, the following errors were
introduced:
  - KUNIT_EXPECT_LE_MSG() uses KUNIT_ASSERTION
  - KUNIT_ASSERT_LT_MSG() uses KUNIT_EXPECTATION
  - KUNIT_ASSERT_GT_MSG() uses KUNIT_EXPECTATION

A failing KUNIT_EXPECT_LE_MSG() test thus prevents further tests from
running, while failing KUNIT_ASSERT_{LT,GT}_MSG() tests do not prevent
further tests from running.  This is contrary to the documentation,
which states that failing KUNIT_EXPECT_* macros allow further tests to
run, while failing KUNIT_ASSERT_* macros should prevent this.

Revert the KUNIT_{ASSERTION,EXPECTATION} switches to fix the behaviour
for the affected macros.

Fixes: 40f39777ce ("kunit: decrease macro layering for integer asserts")
Signed-off-by: Sander Vanheule <sander@svanheule.net>
Reviewed-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-09-01 13:00:32 -06:00
Daniel Latypov e5857d396f kunit: flatten kunit_suite*** to kunit_suite** in .kunit_test_suites
We currently store kunit suites in the .kunit_test_suites ELF section as
a `struct kunit_suite***` (modulo some `const`s).
For every test file, we store a struct kunit_suite** NULL-terminated array.

This adds quite a bit of complexity to the test filtering code in the
executor.

Instead, let's just make the .kunit_test_suites section contain a single
giant array of struct kunit_suite pointers, which can then be directly
manipulated. This array is not NULL-terminated, and so none of the test
filtering code needs to NULL-terminate anything.

Tested-by: Maíra Canal <maira.canal@usp.br>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Daniel Latypov <dlatypov@google.com>
Co-developed-by: David Gow <davidgow@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-07-11 17:13:15 -06:00
Jeremy Kerr 3d6e446238 kunit: unify module and builtin suite definitions
Currently, KUnit runs built-in tests and tests loaded from modules
differently. For built-in tests, the kunit_test_suite{,s}() macro adds a
list of suites in the .kunit_test_suites linker section. However, for
kernel modules, a module_init() function is used to run the test suites.

This causes problems if tests are included in a module which already
defines module_init/exit_module functions, as they'll conflict with the
kunit-provided ones.

This change removes the kunit-defined module inits, and instead parses
the kunit tests from their own section in the module. After module init,
we call __kunit_test_suites_init() on the contents of that section,
which prepares and runs the suite.

This essentially unifies the module- and non-module kunit init formats.

Tested-by: Maíra Canal <maira.canal@usp.br>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: Daniel Latypov <dlatypov@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-07-11 17:13:09 -06:00
Mauro Carvalho Chehab 7b2379454b kunit: test.h: fix a kernel-doc markup
Fix this kernel-doc warning:

	Documentation/dev-tools/kunit/api/test:9: ./include/kunit/test.h:323: WARNING: Inline interpreted text or phrase reference start-string without end-string.

Functions should use func_name() on kernel-doc markups, as
documented at:
	Documentation/doc-guide/kernel-doc.rst

Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-07-08 11:22:47 -06:00
David Gow c272612cb4 kunit: Taint the kernel when KUnit tests are run
Make KUnit trigger the new TAINT_TEST taint when any KUnit test is run.
Due to KUnit tests not being intended to run on production systems, and
potentially causing problems (or security issues like leaking kernel
addresses), the kernel's state should not be considered safe for
production use after KUnit tests are run.

This both marks KUnit modules as test modules using MODULE_INFO() and
manually taints the kernel when tests are run (which catches builtin
tests).

Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Tested-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Tested-by: Maíra Canal <mairacanal@riseup.net>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-07-01 16:38:43 -06:00
Miguel Ojeda 7466886b40 kunit: take `kunit_assert` as `const`
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>
2022-05-16 13:23:00 -06:00
David Gow ad69172ec9 kunit: Rework kunit_resource allocation policy
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 <davidgow@google.com>
Tested-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-05-12 11:14:39 -06:00
Daniel Latypov 1cdba21db2 kunit: add ability to specify suite-level init and exit functions
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>
2022-05-02 12:35:51 -06:00
Brendan Higgins 9bf2eed995 kunit: add support for kunit_suites that reference init code
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>
2022-04-26 18:08:25 -06:00
Daniel Latypov 61695f8c5d kunit: split resource API from test.h into new resource.h
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>
2022-04-04 16:23:08 -06:00
Ricardo Ribalda caae9458db kunit: Introduce _NULL and _NOT_NULL macros
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>
2022-04-04 14:29:02 -06:00
Daniel Latypov c274145347 kunit: cleanup assertion macro internal variables
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>
2022-01-31 11:55:48 -07:00
Daniel Latypov 2b6861e237 kunit: factor out str constants from binary assertion structs
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>
2022-01-31 11:55:39 -07:00
Daniel Latypov 064ff292ac kunit: consolidate KUNIT_INIT_BINARY_ASSERT_STRUCT macros
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>
2022-01-31 11:55:33 -07:00
Daniel Latypov 6419abb80e kunit: remove va_format from kunit_assert
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 <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>
2022-01-31 11:55:27 -07:00
Daniel Latypov 6125a5c70a kunit: decrease macro layering for EQ/NE asserts
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>
2022-01-25 13:04:50 -07:00
Daniel Latypov 40f39777ce kunit: decrease macro layering for integer asserts
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>
2022-01-25 13:04:44 -07:00
Daniel Latypov 955df7d85e kunit: reduce layering in string assertion macros
The current macro chain looks like:
KUNIT_EXPECT_STREQ => KUNIT_EXPECT_STREQ_MSG => KUNIT_BINARY_STR_EQ_MSG_ASSERTION => KUNIT_BINARY_STR_ASSERTION.
KUNIT_ASSERT_STREQ => KUNIT_ASSERT_STREQ_MSG => KUNIT_BINARY_STR_EQ_MSG_ASSERTION => KUNIT_BINARY_STR_ASSERTION.
<ditto for STR_NE>

After this change:
KUNIT_EXPECT_STREQ => KUNIT_EXPECT_STREQ_MSG => KUNIT_BINARY_STR_ASSERTION.
KUNIT_ASSERT_STREQ => KUNIT_ASSERT_STREQ_MSG => KUNIT_BINARY_STR_ASSERTION.
<ditto for STR_NE>

All the intermediate macro did was pass in "==" or "!=", so it seems
better to just drop them at the cost of a bit more copy-paste.

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>
2022-01-25 13:04:38 -07:00
Daniel Latypov c5855907d3 kunit: drop unused intermediate macros for ptr inequality checks
We have the intermediate macros for KUNIT_EXPECT_PTR_GT() and friends,
but these macros don't exist.

I can see niche usecases for these macros existing, but since we've been
fine without them for so long, let's drop this dead code.

Users can instead cast the pointers and use the other GT/LT macros.

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>
2022-01-25 13:04:31 -07:00
Daniel Latypov 6709d0fe55 kunit: make KUNIT_EXPECT_EQ() use KUNIT_EXPECT_EQ_MSG(), etc.
There's quite a few macros in play for KUnit assertions.

The current macro chain looks like:
  KUNIT_EXPECT_EQ => KUNIT_BINARY_EQ_ASSERTION => KUNIT_BINARY_EQ_MSG_ASSERTION
  KUNIT_EXPECT_EQ_MSG => KUNIT_BINARY_EQ_MSG_ASSERTION
  KUNIT_ASSERT_EQ => KUNIT_BINARY_EQ_ASSERTION => KUNIT_BINARY_EQ_MSG_ASSERTION
  KUNIT_ASSERT_EQ_MSG => KUNIT_BINARY_EQ_MSG_ASSERTION

After this change:
  KUNIT_EXPECT_EQ => KUNIT_EXPECT_EQ_MSG => KUNIT_BINARY_EQ_MSG_ASSERTION
  KUNIT_ASSERT_EQ => KUNIT_ASSERT_EQ_MSG => KUNIT_BINARY_EQ_MSG_ASSERTION
and we can drop the intermediate KUNIT_BINARY_EQ_ASSERTION.

This change does this for all the other macros as well.

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>
2022-01-25 13:04:18 -07:00
Daniel Latypov 05a7da89c1 kunit: drop unused assert_type from kunit_assert and clean up macros
This field has been split out from kunit_assert to make the struct less
heavy along with the filename and line number.

This change drops the assert_type field and cleans up all the macros
that were plumbing assert_type into kunit_assert.

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>
2022-01-25 12:50:05 -07:00
Daniel Latypov 21957f90b2 kunit: split out part of kunit_assert into a static const
This is per Linus's suggestion in [1].

The issue there is that every KUNIT_EXPECT/KUNIT_ASSERT puts a
kunit_assert object onto the stack. Normally we rely on compilers to
elide this, but when that doesn't work out, this blows up the stack
usage of kunit test functions.

We can move some data off the stack by making it static.
This change introduces a new `struct kunit_loc` to hold the file and
line number and then just passing assert_type (EXPECT or ASSERT) as an
argument.

In [1], it was suggested to also move out the format string as well, but
users could theoretically craft a format string at runtime, so we can't.

This change leaves a copy of `assert_type` in kunit_assert for now
because cleaning up all the macros to not pass it around is a bit more
involved.

Here's an example of the expanded code for KUNIT_FAIL():
if (__builtin_expect(!!(!(false)), 0)) {
  static const struct kunit_loc loc = { .file = ... };
  struct kunit_fail_assert __assertion = { .assert = { .type ...  };
  kunit_do_failed_assertion(test, &loc, KUNIT_EXPECTATION, &__assertion.assert, ...);
};

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

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-01-25 12:49:59 -07:00
Daniel Latypov a91e9ade40 kunit: drop unused kunit* field in kunit_assert
The `struct kunit* test` field in kunit_assert is unused.
Note: string_stream needs it, but it has its own `test` field. I assume
`test` in `kunit_assert` predates this and was leftover after some
refactoring.

This patch removes the field and cleans up the macros to avoid
needlessly passing around `test`.

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-01-25 12:49:46 -07:00
Daniel Latypov 4fdacef8ac kunit: move check if assertion passed into the macros
Currently the code always calls kunit_do_assertion() even though it does
nothing when `pass` is true.

This change moves the `if(!(pass))` check into the macro instead
and renames the function to kunit_do_failed_assertion().
I feel this a bit easier to read and understand.

This has the potential upside of avoiding a function call that does
nothing most of the time (assuming your tests are passing) but comes
with the downside of generating a bit more code and branches. We try to
mitigate the branches by tagging them with `unlikely()`.

This also means we don't have to initialize structs that we don't need,
which will become a tiny bit more expensive if we switch over to using
static variables to try and reduce stack usage. (There's runtime code
to check if the variable has been initialized yet or not).

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-01-25 12:49:40 -07:00