title: Get current time in seconds in kernel module
body: <p>What is the standard way to get the current time in seconds (since the epoch) in a kernel module?</p>
  
  <p>I have seen techniques involving getting xtime which are very long-winded and involve while-loops and locks. There must be a better way.</p>
  
  <p>[This is not a duplicate. I have looked through previous questions on SO. The answers to many of these either don't specify the function used, or incorrectly refer to time.h which is not allowed in the kernel]</p>