title: How many instructions does Linux kernel need in order to handle an interrupt on an arm cortex A9?
body: <p>I would like to estimate the amount of opcodes it takes a <code>ARM</code> <code>cortex A9</code> single core to handle an IRQ.</p>
  
  <p>Assuming I work with Linux kernel <code>3.4</code>, how many opcodes it takes to call the <code>irq</code> and execute the <code>irq_handler</code> ?</p>