****** perf by examples ******
------------------------------
-[ From an e-mail by Ingo Molnar, http://lkml.org/lkml/2009/8/4/346 ]
+[ From an e-mail by Ingo Molnar, https://lore.kernel.org/lkml/20090804195717.GA5998@elte.hu ]
First, discovery/enumeration of available counters can be done via