Make ondemand sampling per CPU and remove the mutex usage in sampling path.
Signed-off-by: NAlexey Starikovskiy <alexey.y.starikovskiy@intel.com>
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NDave Jones <davej@redhat.com>