pmc: Fix some problems with the makefile

- For some reason we don't build it as a PIE, but I don't have any
problems doing so with either clang or gcc.
- There is no apparent need to override WARNS, so don't.
- Some building with -O0, presumably that's left over from debugging.

MFC after: 1 week
Reviewed by: imp, brooks
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D43923

Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

ncurses: chase dependency changes in the source tree

Differential Revision: https://reviews.freebsd.org/D32098

pmc: diable position-independent builds, they fail to link on amd64

PR: 245189
Reported by: Gordon Bergling
Sponsored by: DARPA

pmc: Add include path for libpmcstat as it is an internallib

Reviewed by: bapt
Differential Revision: https://reviews.freebsd.org/D24173

Standardize `-std=c++* as `CXXSTD`

CXXSTD was added as the C++ analogue to CSTD.

CXXSTD defaults to `-std=c++11` with supporting compilers; `-std=gnu++98`,
otherwise for older versions of g++.

This change standardizes the CXXSTD variable, originally added to
googletest.test.inc.mk as part of r345203.

As part of this effort, convert all `CXXFLAGS+= -std=*` calls to use `CXXSTD`.

Notes:

This value is not sanity checked in bsd.sys.mk, however, given the two
most used C++ compilers on FreeBSD (clang++ and g++) support both modes, it is
likely to work with both toolchains. This method will be refined in the future
to support more variants of C++, as not all versions of clang++ and g++ (for
instance) support C++14, C++17, etc.

Any manual appending of `-std=*` to `CXXFLAGS` should be replaced with CXXSTD.
Example:

Before this commit:
```
CXXFLAGS+= -std=c++14
```

After this commit:
```
CXXSTD= c++14
```

Reviewed by: asomers
Approved by: emaste (mentor)
MFC after: 1 month
MFC with: r345203, r345704, r345705
Relnotes: yes
Tested with: make tinderbox
Differential Revision: https://reviews.freebsd.org/D19732

Revert r345706: the third time will be the charm

When a review is closed via Phabricator it updates the patch attached to the
review. I downloaded the raw patch from Phabricator, applied it, and repeated
my mistake from r345704 by accident mixing content from D19732 and D19738.

For my own personal sanity, I will try not to mix reviews like this in the
future.

MFC after: 1 month
MFC with: r345706
Approved by: emaste (mentor, implicit)

Standardize `-std=c++* as `CXXSTD`

CXXSTD was added as the C++ analogue to CSTD.

CXXSTD defaults to `-std=c++11` with supporting compilers; `-std=gnu++98`,
otherwise for older versions of g++.

This change standardizes the CXXSTD variable, originally added to
googletest.test.inc.mk as part of r345203.

As part of this effort, convert all `CXXFLAGS+= -std=*` calls to use `CXXSTD`.

Notes:

This value is not sanity checked in bsd.sys.mk, however, given the two
most used C++ compilers on FreeBSD (clang++ and g++) support both modes, it is
likely to work with both toolchains. This method will be refined in the future
to support more variants of C++, as not all versions of clang++ and g++ (for
instance) support C++14, C++17, etc.

Any manual appending of `-std=*` to `CXXFLAGS` should be replaced with CXXSTD.
Example:

Before this commit:
```
CXXFLAGS+= -std=c++14
```

After this commit:
```
CXXSTD= c++14
```

Reviewed by: asomers
Approved by: emaste (mentor)
MFC after: 1 month
MFC with: r345203, r345704, r345705
Relnotes: yes
Tested with: make tinderbox
Differential Revision: https://reviews.freebsd.org/D19732

Revert r345704

I accidentally committed code from two reviews. I will reintroduce the code to
bsd.progs.mk as part of a separate commit from r345704.

Approved by: emaste (mentor, implicit)
MFC after: 2 months
MFC with: r345704

CXXSTD is the C++ analogue to CSTD.

CXXSTD defaults to `-std=c++11` with supporting compilers; `-std=gnu++98`,
otherwise for older versions of g++.

This change standardizes the CXXSTD variable, originally added to
googletest.test.inc.mk as part of r345203.

As part of this effort, convert all `CXXFLAGS+= -std=*` calls to use `CXXSTD`.

Notes:

This value is not sanity checked in bsd.sys.mk, however, given the two
most used C++ compilers on FreeBSD (clang++ and g++) support both modes, it is
likely to work with both toolchains. This method will be refined in the future
to support more variants of C++, as not all versions of clang++ and g++ (for
instance) support C++14, C++17, etc.

Any manual appending of `-std=*` to `CXXFLAGS` should be replaced with CXXSTD.
Example:

Before this commit:
```
CXXFLAGS+= -std=c++14
```

After this commit:
```
CXXSTD= c++14
```

Reviewed by: asomers
Approved by: emaste (mentor)
MFC after: 1 month
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D19732

Fix build with GCC 8.1.

GCC 8.1 failed to build LLVM's libc++ when -Wshadow is set,
so lower down WARNS flag to 3.

This is similar to dtc(1) which uses libc++ and sets WARNS to 3.

Approved by: re (gjb)
Sponsored by: DARPA, AFRL

pmc gcc fixups

Fix the build of lib/libpmc and usr.sbin/pmc for gcc on amd64.

Reviewed by: mmacy
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D15723

pmc: convert native to jsonl and track TSC value of samples

- add '-j' options to filter to enable converting native pmc
log format to json lines format to enable the use of scripts
and external tooling

% pmc filter -j pmc.log pmc.jsonl

- Record the tsc value in sampling interrupts as opposed to
recording nanotime when the sample is copied to a global log
in hardclock - potentially many milliseconds later.

- At initialize record the tsc_freq and the time of day to give
us an offset for translating the tsc values in callchain records

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

hwpmc: log name->pid, name->tid mappings

By logging all threads and processes 'pmc filter'
can now filter on process or thread name, relieving
the user of the burden of determining which tid or
pid was which when the sample was taken.

% pmc filter -T if_io_tqg -P nginx pmc.log pmc-iflib.log

% pmc filter -x -T idle pmc.log pmc-noidle.log

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 stat: fix format strings for 32-bit

pmc: don't break build with format issues

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