Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

pmc: remove trailing whitespace

Reported by: swills

pmc: mark some dead functions as such

Also change a single instance of the comma operator to a semi-colon.

Reviewed by: mmacy

hwpmc: add summary command and further metadata extensions

metadata changes:
- log pmc sample rate with pmcallocate
- log proc flags with thread / process logging
to identify user vs kernel threads

fixes:
- use log cpuid to translate event id to event name

Implement rudimentary summary command to track sample
counts by thread and process name within a pmc log.

% make -j4 buildkernel >& /dev/null &
% sudo pmcstat -S unhalted_core_cycles -S llc-misses -O foo sleep 15
% pmc summary foo
cpu_clk_unhalted.thread_p_any:
idle: 138108207162
clang-6.0: 105336158004
sh: 72340108510
make: 8642012963
kernel: 7754011631
longest_lat_cache.miss:
clang-6.0: 87502625
sh: 40901227
make: 5500165
kernel: 3300099
awk: 2000060

% pmc summary -f ~/foo
idx: 278 name: cpu_clk_unhalted.thread_p_any rate: 2000003
idle: 69054
clang-6.0: 52668
sh: 36170
make: 4321
kernel: 3877
hwpmc: proc(7445): 3319
awk: 1289
xargs: 357
rand_harvestq: 181
mtree: 102
intr: 53
zfskern: 31
usb: 7
pagedaemon: 4
ntpd: 3
syslogd: 1
acpi_thermal: 1
logger: 1
syncer: 1
snmptrapd: 1
sleep: 1
idx: 17 name: longest_lat_cache.miss rate: 100003
clang-6.0: 875
sh: 409
make: 55
kernel: 33
awk: 20
hwpmc: proc(7445): 14
xargs: 9
idle: 8
intr: 3
zfskern: 2

pmc: add filter command

pmc filter allows the user to select event types, threads, and processes from
a sample.

% pmcstat -S unhalted_core_cycles -S llc-misses -S -S resource_stalls.any -O pmc.log
% pmc filter -e llc-misses pmc.log pmc-llc-misses.log
% pmc filter -e unhalted_core_cycles -t 100339 pmc.log pmc-core-cycles.log
etc...
% pmcstat -R pmc-core-cycles.log -G pmc-core-cycles.stacks

pmc: add list-events command

pmc: Add new sub-command structured "pmc" utility

This will manage pmc functionality with a more
manageable structure of subcommands rather than the
gradually accreted spaghetti logic of overlapping flags
that exists in pmcstat.

This is intended to ultimately have all the same functionality
as pmcannotate+pmccontrol+pmcstat. Currently it just has
"stat" and "system-stat" - counters for the process itself and counters
for the system as a whole respectively (i.e. system-stat includes kernel
threads). Note that the rusage results (page faults/context switches/
user/sys) for stat-system will not account for the system as a whole -
only for the child process specified on the command line.

Implementing stat was suggested by mjg@ and the output is based on that
from Linux's "perf stat".

% pmc stat -- make -j32 buildkernel -DNO_MODULES -ss > /dev/null
9598393 page faults # 0.674 M/sec
387085 voluntary csw # 0.027 M/sec
106989 involuntary csw # 0.008 M/sec
2763965982317 cycles
2542953049760 instructions # 0.920 inst/cycle
511562750157 branches
12917006881 branch-misses # 2.525%
17944429878 cache-references # 0.007 refs/inst
2205119560 cache-misses # 12.289%
43.74 real # 2019.72% cpu
795.09 user # 1817.72% cpu
88.35 sys # 202.00% cpu

% make -j32 buildkernel -DNO_MODULES -ss > /dev/null &
% sudo pmc stat-system cat
^C 103 page faults # 0.811 M/sec
4 voluntary csw # 0.031 M/sec
0 involuntary csw # 0.000 M/sec
2843639070514 cycles
2606171217438 instructions # 0.916 inst/cycle
522450422783 branches
13092862839 branch-misses # 2.506%
18592101113 cache-references # 0.007 refs/inst
2562878667 cache-misses # 13.785%
44.85 real # 0.00% cpu
0.00 user # 0.00% cpu
0.00 sys # 0.00% cpu