Jonathan T. Looney c66ea2ee5c Optimizations to the way hwpmc gathers user callchains
Changes to the code to gather user stacks:
* Delay setting pmc_cpumask until we actually have the stack.
* When recording user stack traces, only walk the portion of the ring
  that should have samples for us.

Sponsored by:	Juniper Networks
Approved by:	gnn (mentor)
MFC after:	1 month
2015-11-14 01:45:55 +00:00
..