On Fri, Nov 25, 2022 at 04:43:05PM +0800, David Gow wrote:
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: Kees Cook keescook@chromium.org