NAME = "Priority inversion tests" AUTHOR = "Michal Piotrowski " TIME = "SHORT" TEST_CATEGORY = "FUNCTIONAL" TEST_CLASS = "KERNEL" TEST_TYPE = "CLIENT" DOC = """ The basic premise here is to set up a deadlock scenario and confirm that PI mutexes resolve the situation. Three worker threads will be created from the main thread: low, medium and high priority threads that use SCHED_FIFO as their scheduling policy. The low priority thread claims a mutex and then starts "working". The medium priority thread starts and preempts the low priority thread. Then the high priority thread runs and attempts to claim the mutex owned by the low priority thread. Without priority inheritance, this will deadlock the program. With priority inheritance, the low priority thread receives a priority boost, finishes it's "work" and releases the mutex, which allows the high priority thread to run and finish and then the medium priority thread finishes. That's the theory, anyway... """ job.run_test('pi_tests')