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

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

Remove useless Ta macro.

Update manual pages for MIPS-related CPUs:

- Rename pmc.mips to pmc.mips24k since it covers just one CPU,
no whole architecture
- Add documetnations for Octeon's PMC counters
- Remove CAVEATS section from pmc.mips24k page: PMC for MIPS supports
sampling now.

Whitespace cleanup:
o Wrap sentences on to new lines
o Cleanup trailing whitespace

Found with: textproc/igor
MFC after: 1 week
X-MFC-With: r232157

Fix various typos in manual pages.

Submitted by: amdmi3
PR: 165431
MFC after: 1 week

Switch the license boilerplates to our standard one.

Advantages:
- Reduces the number of different license versions in the tree
- Eliminates a typo
- Removes some incorrect author attributions due to c/p
- Removes c/p error potential for future pmc manpages

Approved by: jkoshy, gnn, rpaulo, fabient (copyright holders)
MFC after: 1 week

Fix manpage markup.

Fix typos and spelling mistakes.

mdoc: move CAVEATS, BUGS and SECURITY CONSIDERATIONS sections to the
bottom of the manpages and order them consistently.

GNU groff doesn't care about the ordering, and doesn't even mention
CAVEATS and SECURITY CONSIDERATIONS as common sections and where to put
them.

Found by: mdocml lint run
Reviewed by: ru

Add support for hwpmc(4) on the MIPS 24K, 32 bit, embedded processor.

Add macros for properly accessing coprocessor 0 registers that
support performance counters.

Reviewed by: jkoshy rpaulo fabien imp
MFC after: 1 month