Listing 5: (a) RTLinux interrupt latency dispatch test; (b) RTLinux jitter output.

(a)
ISR
   start = rtl_getticks();
   sem_post(&semaphore);
Thread
   sem_wait(&semaphore);
   ticks = rtl_getticks() - start;

(b)
Interrupt Thread Latency - Realtime ISR to Realtime thread (via Semaphore):  (46.0 us