title: Can not use Linux perf because your Linux kernel does not support PERF_COUNT_HW_REF_CPU_CYCLES event
body: <p>I just want a information about linux "perf" for virtual environment. I am trying to get perf stat -e cycles "my process", so when i run this command on my VM(which is running on top of Vmware5.1)i got the message like..</p>
  
  <p>/not supported>      cycles</p>
  
  <pre><code>  10.498901015 seconds time elapsed
  </code></pre>
  
  <p>i could under stand there might be a permissions issue or configuration error for VMware hypervisor, can some one point-out those?. Also , i have read about kernel flag "PERF_COUNT_HW_REF_CPU_CYCLES",how should i check whether my kernel has this flag enabled or not? is there any command for this? </p>