RING_WAIT
if (ttymsg(&iovec, 1, tty, RING_WAIT - 5) != NULL)
if (val & RING_WAIT)
I915_READ(RING_CTL(engine->mmio_base)) & (RING_WAIT | RING_WAIT_SEMAPHORE) ? " [waiting]" : "");
if (tmp & RING_WAIT) {
itimer.it_value.tv_sec = RING_WAIT;