What could be the reason for infinite loop in our code when dealing with sequence and driver

UVM
1

Let’s consider an example where in which I have one sequence and one driver. The drive code is

forever begin
     seq_item_port.get_next_item(req);
     send_to_dut(req);
     seq_item_port.item_done();
end

In test lets assume I am starting the sequence on the sequencer.

Now In the task body of the sequence

task body()
      repeat(10) begin
      req // object creation
      start_item(req);
      assert(req.randomize());
      finish_item(req);
endtask

Now the problem is that for the first trans I am getting the output but for the next tranx which is the 2nd tranx, I am going to infinite loop. The driver code is not sending the item done. hence waiting infinitely.

what could be the reasons behind the condition…?

2

If the driver is not sending item_done(), then there is an issue in your send_to_dut() task.

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