Concurrent write or read/write access from applications to the resctrlfs
directory can result in incorrect readouts or setups.

Recommend a standard locking scheme for applications to use.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/20161214170835.GA16924@amt.cnetSigned-off-by: Thomas Gleixner <tglx@linutronix.de>