12  * This module demonstrates the kernel's priority inheritance algorithm.
13  * A thread that owns a mutex is promoted to the priority level of the
14  * highest-priority thread attempting to lock the mutex.
24  * Timeline for priority inheritance testing:
29  *   - 1.0  sec: main thread (@ priority 9) takes mutex_2 then sleeps
31  *   - 2.0  sec: main thread (@ priority 8) takes mutex_3 then sleeps
33  *   - 3.0  sec: main thread (@ priority 7) takes mutex_4 then sleeps
37  *   - 4.0  sec: main thread wakes (@ priority 5) then sleeps
39  *   - 5.0  sec: main thread wakes (@ priority 6) then gives mutex_4
40  *             : main thread (@ priority 7) sleeps
42  *   - 6.0  sec: main thread (@ priority 8) gives mutex_3
43  *             : main thread (@ priority 8) gives mutex_2
44  *             : main thread (@ priority 9) gives mutex_1
45  *             : main thread (@ priority 10) sleeps
113 	/* Wait and boost owner priority to 5 */  in thread_05()
140 	 * Wait for the mutex.  There is a higher priority level thread waiting  in thread_06()
142 	 * the priority of the owning thread (main thread).  When thread_05  in thread_06()
143 	 * times out this thread will become the highest priority waiting  in thread_06()
144 	 * thread. The priority of the owning thread (main thread) will not  in thread_06()
175 	 * Wait and boost owner priority to 7.  While waiting, another thread of  in thread_07()
176 	 * a very low priority level will also wait for the mutex.  thread_07 is  in thread_07()
179 	 * priority of the owning main thread will drop to 8.  in thread_07()
207 	/* Wait and boost owner priority to 8 */  in thread_08()
232 	k_sleep(K_MSEC(500));	/* Allow lower priority thread to run */  in thread_09()
243 	/* Wait and boost owner priority to 9 */  in thread_09()
335 	 * Main thread(test_main) priority was 10 but ztest thread runs at  in ZTEST_USER_OR_NOT()
336 	 * priority -1. To run the test smoothly make both main and ztest  in ZTEST_USER_OR_NOT()
337 	 * threads run at same priority level.  in ZTEST_USER_OR_NOT()
346 	int priority[4] = { 9, 8, 7, 5 };  in ZTEST_USER_OR_NOT()  local
364 		zassert_equal(rv, priority[i], "expected priority %d, not %d\n",  in ZTEST_USER_OR_NOT()
365 			      priority[i], rv);  in ZTEST_USER_OR_NOT()
373 	TC_PRINT("Done LOCKING!  Current priority = %d\n",  in ZTEST_USER_OR_NOT()
381 	zassert_equal(rv, 6, "%s timed out and out priority should drop.\n",  in ZTEST_USER_OR_NOT()
383 	zassert_equal(rv, 6, "Expected priority %d, not %d\n", 6, rv);  in ZTEST_USER_OR_NOT()
387 	zassert_equal(rv, 7, "Gave %s and priority should drop.\n", "mutex_4");  in ZTEST_USER_OR_NOT()
388 	zassert_equal(rv, 7, "Expected priority %d, not %d\n", 7, rv);  in ZTEST_USER_OR_NOT()
396 		zassert_equal(rv, droppri[i], "Expected priority %d, not %d\n",  in ZTEST_USER_OR_NOT()
404 	zassert_equal(rv, 10, "Expected priority %d, not %d\n", 10, rv);  in ZTEST_USER_OR_NOT()