* Style(9).   Start non-Copyright fancy formatted comments with /**.

Reviewed by:	bde (as part of larger diff)
cxgbe(4): t4fw_cfg must be explicitly loaded if the driver is being
loaded via loader.conf.

Submitted by:	jwd@
MFC after:	3 days
Remove irrelevant comments.

Discussed with:	alc
MFC after:	3 days
* Rename the polynomial coefficients from P2, P3, ... to A2, A3, ....
  The names now coincide with the name used in PTP Tang's paper.

* Rename the variable from s to tbl to better reflect that
  this is a table, and to be consistent with the naming scheme
  in s_exp2l.c

Reviewed by:	bde (as part of larger diff)
Be more generous when donating the current thread time to the owner of
the vnode lock while iterating over the free vnode list.  Instead of
yielding, pause for 1 tick.  The change is reported to help in some
virtualized environments.

Submitted by:	Roger Pau Monn? <roger.pau@citrix.com>
Discussed with:	jilles
Tested by:	pho
MFC after:	2 weeks
- Handle the recursed/not recursed flags with RA_RLOCKED in rw_assert().
- Tweak a panic message.
Assert that interrupts are enabled in the trap handlers on x86 before
calling generic code to deliver signals.

Discussed with:	bde
Tested by:	pho
MFC after:	1 week
Whitespace.
- Fix a couple of inverted panic messages for shared/exclusive mismatches
  of a lock within a single thread.
- Fix handling of interlocks in WITNESS by properly requiring the interlock
  to be held exactly once if it is specified.
Introduce the macro LOG2_INTERVAL, which is log2(number of intervals).
Use the macroi as a micro-optimization to convert a subtraction and
division to a shift.

Obtained from:	bde
Add a u suffix to the IEEEl2bits unions o_threshold and u_threshold,
and use macros to access the e component of the unions.  This allows
the portions of the code in ld80 to be identical to the ld128 code.

Obtained from:	bde
Update a comment to reflect that we are using an endpoint of
an interval instead of a midpoint.
Rename a few P2, P3, ... coefficients to A2, A3, ... missed in
my previous commit.