Konstantin Belousov 411c83ccd6 If full width writes to the performance monitoring counters are
supported, use full-width aliases MSRs for writes.  This fixes the
"[pmc,X] negative increment" assertion on the context switch when
clipped counter value is sign-extended.

Add definitions for the MSR IA32_PERF_CAPABILITIES needed to detect
the feature.

PR:	207068
Submitted by:	joss.upton@yahoo.com
MFC after:	2 weeks
2016-02-12 07:27:24 +00:00
..
2016-02-12 07:19:59 +00:00