tests: rtio: workq: Add test-case for same-prio items

Processed on separate worker threads. This test is expected to fail
as the P4WQ limits the number of active items assigned to worker
threads to the number of CPU cores the system has.

Signed-off-by: Luis Ubieda <luisf@croxel.com>

Author: ubieda

tests/subsys/rtio/workq/src/main.c

@@ -128,6 +128,39 @@ ZTEST(rtio_work, test_work_supports_batching_submissions)
 	rtio_cqe_release(&r_test, cqe);
 }
 
+ZTEST(rtio_work, test_work_supports_working_same_prio_items_on_separate_threads)
+{
+	struct rtio_sqe *sqe_a;
+	struct rtio_sqe *sqe_b;
+	struct rtio_cqe *cqe;
+
+	sqe_a = rtio_sqe_acquire(&r_test);
+	rtio_sqe_prep_nop(sqe_a, &dummy_iodev, &work_handler_sem_1);
+	sqe_a->prio = RTIO_PRIO_NORM;
+
+	sqe_b = rtio_sqe_acquire(&r_test_2);
+	rtio_sqe_prep_nop(sqe_b, &dummy_iodev_2, &work_handler_sem_2);
+	sqe_b->prio = RTIO_PRIO_NORM;
+
+	zassert_ok(rtio_submit(&r_test, 0));
+	zassert_ok(rtio_submit(&r_test_2, 0));
+
+	zassert_equal(2, work_handler_called);
+	zassert_equal(2, rtio_work_req_used_count_get());
+
+	k_sem_give(&work_handler_sem_1);
+	k_sem_give(&work_handler_sem_2);
+
+	zassert_equal(2, work_handler_called);
+	zassert_equal(0, rtio_work_req_used_count_get());
+
+	/** Clean-up */
+	cqe = rtio_cqe_consume_block(&r_test);
+	rtio_cqe_release(&r_test, cqe);
+	cqe = rtio_cqe_consume_block(&r_test_2);
+	rtio_cqe_release(&r_test_2, cqe);
+}
+
 ZTEST(rtio_work, test_work_supports_preempting_on_higher_prio_submissions)
 {
 	struct rtio_sqe *sqe_a;