Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Update hwpmc to support the Xeon class of Ivybridge processors.
case 0x3E: /* Per Intel document 325462-045US 01/2013. */

Add manpage to document all the goodness that is available in this
processor model.

No support for uncore events at this time.

Submitted by: hiren panchasara <hiren.panchasara@gmail.com>
Reviewed by: davide, jimharris, sbruno
Obtained from: Yahoo! Inc.
MFC after: 2 weeks

Cleanup and rename some variables in libpmc and hwpmc.

Submitted by: hiren panchasara <hiren.panchasara@gmail.com>
Reviewed by: jimharris@ sbruno@
Obtained from: Yahoo! Inc.
MFC after: 2 weeks

Update man page crossreferences to sandybridge xeon class

MFC after: 2 weeks

Add Intel Ivy Bridge support to hwpmc(9).
Update offcore RSP token for Sandy Bridge.
Note: No uncore support.

Will works on Family 6 Model 3a.

MFC after: 1 month
Tested by: bapt, grehan

Add software PMC support.

New kernel events can be added at various location for sampling or counting.
This will for example allow easy system profiling whatever the processor is
with known tools like pmcstat(8).

Simultaneous usage of software PMC and hardware PMC is possible, for example
looking at the lock acquire failure, page fault while sampling on
instructions.

Sponsored by: NETASQ
MFC after: 1 month

Kill EoL whitespaces, and minor lint.

- Add support for the Intel Sandy Bridge microarchitecture (both core and uncore counting events)
- New manpages with event lists.
- Add MSRs for the Intel Sandy Bridge microarchitecture

Reviewed by: attilio, brueffer, fabient
Approved by: gnn (mentor)
MFC after: 3 weeks