kunit.py will attempt to catch SIGINT / ^C in order to ensure the TTY isn't
messed up, but never actually attempts to terminate the running kernel (be
it UML or QEMU). This can lead to a bit of frustration if the kernel has
crashed or hung.

Terminate the kernel process in the signal handler, if it's running. This
requires plumbing through the process handle in a few more places (and
having some checks to see if the kernel is still running in places where it
may have already been killed).

Reported-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Closes: https://lore.kernel.org/all/aaFmiAmg9S18EANA@smile.fi.intel.com/
Signed-off-by: David Gow <david@davidgow.net>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Tested-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

run_kernel() cleanup and signal_handler() invoke stty unconditionally.
When stdin is not a tty (for example in CI or unit tests), this writes
noise to stderr.

Call stty only when stdin is a tty.

Add regression tests for these paths:
- run_kernel() with non-tty stdin
- signal_handler() with non-tty stdin
- signal_handler() with tty stdin

Signed-off-by: Shuvam Pandey <shuvampandey1@gmail.com>
Reviewed-by: David Gow <david@davidgow.net>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

run_kernel() appended KUnit flags directly to the caller-provided args
list. When exec_tests() calls run_kernel() repeatedly (e.g. with
--run_isolated), each call mutated the same list, causing later runs
to inherit stale filter_glob values and duplicate kunit.enable flags.

Fix this by copying args at the start of run_kernel(). Add a regression
test that calls run_kernel() twice with the same list and verifies the
original remains unchanged.

Fixes: ff9e09a3762f ("kunit: tool: support running each suite/test separately")
Signed-off-by: Shuvam Pandey <shuvampandey1@gmail.com>
Reviewed-by: David Gow <david@davidgow.net>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

To implement custom scripting around kunit.py it is useful to get a list of
available architectures. While it is possible to manually inspect
tools/testing/kunit/qemu_configs/, this is annoying to implement and
introduces a dependency on a kunit.py implementation detail.

Introduce 'kunit.py run --arch help' which lists all known architectures
in an easy to parse list. This is equivalent on how QEMU implements
listing of possible argument values.

Link: https://lore.kernel.org/r/20250415-kunit-list-v2-1-aa452cd317ae@linutronix.de
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Rae Moar <rmoar@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Following a similar rationale as commit e4835f1da425f ("kunit: tool:
Build compile_commands.json"), make a common developer tool available by
default for KUnit users.

Compared to compile_commands.json, there is a little more work to be
done to build the GDB scripts. Is it enough to affect development cycle
duration? Unscientific evaluation:

rm -rf .kunit; time tools/testing/kunit/kunit.py build --kunitconfig ./lib/kunit/.kunitconfig --jobs 96

Without this patch it took 14.77s, with this patch it took 14.83. So,
although `make scripts_gdb` is pretty slow, presumably most of that is
just the overhead of running Kbuild at all, actually building the
scripts is approximately free.

Note also, to actually get the GDB scripts the user needs to enable
CONFIG_SCRIPTS_GDB, but building the scripts_gdb target without that is
still harmless.

Link: https://lore.kernel.org/r/20250121-kunit-gdb-v1-1-faedfd0653ef@google.com
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Use KVM or HVF if supported by the QEMU binary and available on the
system.

This produces a nice improvement on my Apple M3 Pro running macOS 14.7:

Before:
./tools/testing/kunit/kunit.py exec --arch arm64
[HH:MM:SS] Elapsed time: 10.145s

After:
./tools/testing/kunit/kunit.py exec --arch arm64
[HH:MM:SS] Elapsed time: 1.773s

Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Not all platforms support machine reboot.
If it a proper reboot is not supported the machine will hang.
Allow the QEMU configuration to override the necessary shutdown mode for
the specific system under test.

Link: https://lore.kernel.org/r/20241111-kunit-loongarch-v2-2-7676eb5f2da3@linutronix.de
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

compile_commands.json is used by clangd[1] to provide code navigation
and completion functionality to editors. See [2] for an example
configuration that includes this functionality for VSCode.

It can currently be built manually when using kunit.py, by running:

  ./scripts/clang-tools/gen_compile_commands.py -d .kunit

With this change however, it's built automatically so you don't need to
manually keep it up to date.

Unlike the manual approach, having make build the compile_commands.json
means that it appears in the build output tree instead of at the root of
the source tree, so you'll need to add --compile-commands-dir=.kunit to
your clangd args for it to be found. This might turn out to be pretty
annoying, I'm not sure yet. If so maybe we can later add some hackery to
kunit.py to work around it.

[1] https://clangd.llvm.org/
[2] https://github.com/FlorentRevest/linux-kernel-vscode

Signed-off-by: Brendan Jackman <jackmanb@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

As for the Qemu command, print the command used to run tests with UML.

Cc: Brendan Higgins <brendan.higgins@linux.dev>
Cc: David Gow <davidgow@google.com>
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

Add ability to kunit.py to filter attributes and report a list of tests
including attributes without running tests.

Add flag "--filter" to input filters on test attributes. Tests will be
filtered out if they do not match all inputted filters.

Example: --filter speed=slow (This filter would run only the tests that are
marked as slow)

Filters have operations: <, >, <=, >=, !=, and =. But note that the
characters < and > are often interpreted by the shell, so they may need to
be quoted or escaped.

Example: --filter "speed>slow" or --filter speed\>slow (This filter would
run only the tests that have the speed faster than slow.

Additionally, multiple filters can be used.

Example: --filter "speed=slow, module!=example" (This filter would run
only the tests that have the speed slow and are not in the "example"
module)

Note if the user wants to skip filtered tests instead of not
running/showing them use the "--filter_action=skip" flag instead.

Expose the output of kunit.action=list option with flag "--list_tests" to
output a list of tests. Additionally, add flag "--list_tests_attr" to
output a list of tests and their attributes. These flags are useful to see
tests and test attributes without needing to run tests.

Example of the output of "--list_tests_attr":
  example
  example.test_1
  example.test_2
  # example.test_2.speed: slow

This output includes a suite, example, with two test cases, test_1 and
test_2. And in this instance test_2 has been marked as slow.

Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Rae Moar <rmoar@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>