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

MFC: 266209

Add a command line argument (-l) to end event collection after some
number of seconds. The number of seconds may be a fraction.

Submitted by: Julien Charbon <jcharbon@versign.com>
Relnotes: yes

Merged r262424-262425,265085

Add the -a option to pmcstat. This produces a full stack track on the
sampled points. See the man page for details on how this works.

Obtained from: Netflix, Inc.

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

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

More -Wmissing-variable-declarations fixes.

In addition to adding `static' where possible:

- bin/date: Move `retval' into extern.h to make it visible to date.c.
- bin/ed: Move globally used variables into ed.h.
- sbin/camcontrol: Move `verbose' into camcontrol.h and fix shadow warnings.
- usr.bin/calendar: Remove unneeded variables.
- usr.bin/chat: Make `line' local instead of global.
- usr.bin/elfdump: Comment out unneeded function.
- usr.bin/rlogin: Use _Noreturn instead of __dead2.
- usr.bin/tset: Pull `Ospeed' into extern.h.
- usr.sbin/mfiutil: Put global variables in mfiutil.h.
- usr.sbin/pkg: Remove unused `os_corres'.
- usr.sbin/quotaon, usr.sbin/repquota: Remove unused `qfname'.

Add -m option (for printing sampled PCs to a file) to pmcstat usage
message.

Sponsored by: Intel
MFC after: 3 days

Fix warning when compiling with gcc46:
error: variable 'current_cpu' set but not used

Approved by: dim, cperciva (mentor, blanket for pre-mentorship already-approved commits)
MFC after: 3 days

Spelling fixes for usr.sbin/

Improve the chances of matching an outputted string with the line of code.

- fix duplicate "a a" in some comments

Submitted by: eadler
Approved by: simon
MFC after: 3 days

Two bugs fixed:
- Do not close stdout or stderr when redirecting to file.
- Correctly handle error code to detect when no buffer available.

MFC after: 1 month

Add a flush of the current PMC log buffer before displaying the next top.

As the underlying block is 4KB if the PMC throughput is low the measurement
will be reported on the next tick. pmcstat(8) use the modified flush API to
reclaim current buffer before displaying next top.

MFC after: 1 month

Convert pmcstat about using cpuset_t rather than relying on plain 32 bit
ints. That fixes a first bug where pmcstat wasn't using the old
cpumask_t interface and now also brings the full support for more
than 32 cpus.

While here, make the functions pmcstat_clone_event_descriptor() and
pmcstat_get_cpumask() private to pmcstat.

The problem of assuming cpu dense masks still persists and should be
eventually fixed, as reported by avg.

Tested by: pluknet
Reviewed by: gnn
Approved by: re (kib)

pmcstat, pmccontrol: catch up with removal of machdep.hlt_cpus sysctl

Reported by: Pan Tsu <inyaoo@gmail.com>
Reviewed by: attilio
No objections: gnn

- Do not use the runtime mask when logfile is specified.
- Revert the fix on rtld path that is not necessary.

MFC after: 1 week

Allow file as a top source, it works with socket now.
This will allow top monitoring using socket/ssh tunnelling
of system without local symbols.

client:
pmcstat -R <ip>:<port> -T -r <symbolspath>
monitored device:
pmcstat -Sinstructions -O <ip>:<port>

- Move the file read in the event loop
- Initialize and clean log in all cases
- Preserve global stats value during top refresh
- Fix the rtld/line resolver that ignore '-r' prefix
- Support socket for '-R' (server mode)
- Display the statistics when exiting top mode

Fix warnings found by Coverity.

Found with: Coverity Prevent(tm)
MFC after: 1 month

Bug fixed:
- no display on serial terminal in top mode.
- display alignment for continuation string.
- correct invalid value used for display limit.

MFC after: 3 days

- Reorganize code in 'plugin' to share log processing.
- Kcachegrind (calltree) support with assembly/source
code mapping and call count estimator (-F).
- Top mode for calltree and callgraph plugin (-T).

MFC after: 1 month

Close the read side of the pipe to self when exiting.

Add the -m option to pmcstat.
This option prints the list of sampled PCs along with the function name,
the start and end addresses of this where their live within.

Reviewed by: jkoshy
Tested by: gnn
Sponsored by: Nokia

As a matter of good programming style, stop PMCs before releasing
them.

- Avoid a spurious error when a command line is specified without
any process scope PMCs.
- Change the -c '*' option to denote non-halted CPUs.

Bring the usage message in sync with the manual page.

Fix a regression: attach process PMCs to the process created when
a command line is specified.

Fix non-SMP kernel regression introduced in the previous commit.

Reviewed by: jkoshy

Introduce pmcstat(8) changes for summarizing hwpmc(4) callchain records in
in textual form and in gmon.out format.

Update manual page.

Sponsored by: FreeBSD Foundation and Google Inc.

MFP4: Enhancements to pmcstat(8):

- Allow the "-t" option to take a regular expression naming command
line processes to attach process PMCs to.

- Update the manual page and add an example showing the use of the
new functionality.

- Update the (c) year on the affected source files.

MFP4: Enhancements and bug-fixes to pmcstat(8):

- The '-c' option now takes a comma-separated list of CPU
numbers, or a literal '*' denoting all CPUs in the system.
Subsequent system PMCs are allocated on the CPUs so specified.

Change the default behaviour to allocate system PMCs on all CPUs,
not just CPU 0.

Update the manual page and add an example of how to use the new
functionality.

- Attach PMCs to a (commandline) child process more reliably. This
fixes a long standing bug in counting events incurred by short-lived
processes.

Correct a sanity check.

Line up usage output.

- Teach pmcstat(8) to log over the network; the -O option now
takes a host:port specification.
- Update the manual page and add an example showing how log
over the network using pmcstat(8) and nc(1). Document the
current inability to process logs in cross-platform manner.
- Have pmcstat_open_log() call err(3) directly in case
of an error; this simplifies error handling in its caller.

MFC after: 1 week

MFP4: Support for profiling dynamically loaded objects.

Kernel changes:

Inform hwpmc of executable objects brought into the system by
kldload() and mmap(), and of their removal by kldunload() and
munmap(). A helper function linker_hwpmc_list_objects() has been
added to "sys/kern/kern_linker.c" and is used by hwpmc to retrieve
the list of currently loaded kernel modules.

The unused `MAPPINGCHANGE' event has been deprecated in favour
of separate `MAP_IN' and `MAP_OUT' events; this change reduces
space wastage in the log.

Bump the hwpmc's ABI version to "2.0.00". Teach hwpmc(4) to
handle the map change callbacks.

Change the default per-cpu sample buffer size to hold
32 samples (up from 16).

Increment __FreeBSD_version.

libpmc(3) changes:

Update libpmc(3) to deal with the new events in the log file; bring
the pmclog(3) manual page in sync with the code.

pmcstat(8) changes:

Introduce new options to pmcstat(8): "-r" (root fs path), "-M"
(mapfile name), "-q"/"-v" (verbosity control). Option "-k" now
takes a kernel directory as its argument but will also work with
the older invocation syntax.

Rework string handling in pmcstat(8) to use an opaque type for
interned strings. Clean up ELF parsing code and add support for
tracking dynamic object mappings reported by a v2.0.00 hwpmc(4).

Report statistics at the end of a log conversion run depending
on the requested verbosity level.

Reviewed by: jhb, dds (kernel parts of an earlier patch)
Tested by: gallatin (earlier patch)

- Don't print an errno string when reporting dropped samples.
- Prevent an unsuccessful exec() of a target program from triggering
a false 'dropped samples' message.

Warn the user if the kernel driver dropped samples or ran out of event buffers
during a data collection run.

Improve an error message.

MFC after: 3 days

Correctly print system-wide PMC counts for short-lived command lines.

Reported by: cracauer
MFC after: 3 days

Sync usage message with the code and manual page.

Submitted by: maxim

Fix a bug that affected on-the-fly gmon.out file generation.

Approved by: re (scottl)

MFP4:

- pmcstat(8) gprof output mode fixes:

lib/libpmc/pmclog.{c,h}, sys/sys/pmclog.h:
+ Add a 'is_usermode' field to the PMCLOG_PCSAMPLE event
+ Add an 'entryaddr' field to the PMCLOG_PROCEXEC event,
so that pmcstat(8) can determine where the runtime loader
/libexec/ld-elf.so.1 is getting loaded.

sys/kern/kern_exec.c:
+ Use a local struct to group the entry address of the image being
exec()'ed and the process credential changed flag to the exec
handling hook inside hwpmc(4).

usr.sbin/pmcstat/*:
+ Support "-k kernelpath", "-D sampledir".
+ Implement the ELF bits of 'gmon.out' profile generation in a new
file "pmcstat_log.c". Move all log related functions to this
file.
+ Move local definitions and prototypes to "pmcstat.h"

- Other bug fixes:
+ lib/libpmc/pmclog.c: correctly handle EOF in pmclog_read().
+ sys/dev/hwpmc_mod.c: unconditionally log a PROCEXIT event to all
attached PMCs when a process exits.
+ sys/sys/pmc.h: correct a function prototype.
+ Improve usage checks in pmcstat(8).

Approved by: re (blanket hwpmc)

MFP4:

- Implement sampling modes and logging support in hwpmc(4).

- Separate MI and MD parts of hwpmc(4) and allow sharing of
PMC implementations across different architectures.
Add support for P4 (EMT64) style PMCs to the amd64 code.

- New pmcstat(8) options: -E (exit time counts) -W (counts
every context switch), -R (print log file).

- pmc(3) API changes, improve our ability to keep ABI compatibility
in the future. Add more 'alias' names for commonly used events.

- bug fixes & documentation.

Neaten usage message.

Add convenience APIs pmc_width() and pmc_capabilities() to -lpmc.
Have pmcstat(8) and pmccontrol(8) use these APIs.

Return PMC class-related constants (PMC widths and capabilities)
with the OP GETCPUINFO call leaving OP PMCINFO to return only the
dynamic information associated with a PMC (i.e., whether enabled,
owner pid, reload count etc.).

Allow pmc_read() (i.e., OPS PMCRW) on active self-attached PMCs to
get upto-date values from hardware since we can guarantee that the
hardware is running the correct PMC at the time of the call.

Bug fixes:
- (x86 class processors) Fix a bug that prevented an RDPMC
instruction from being recognized as permitted till after the
attached process had context switched out and back in again after
a pmc_start() call.

Tighten the rules for using RDPMC class instructions: a GETMSR
OP is now allowed only after an OP ATTACH has been done by the
PMC's owner to itself. OP GETMSR is not allowed for PMCs that
track descendants, for PMCs attached to processes other than
their owner processes.

- (P4/HTT processors only) Fix a bug that caused the MI and MD
layers to get out of sync. Add a new MD operation 'get_config()'
as part of this fix.

- Allow multiple system-mode PMCs at the same row-index but on
different CPUs to be allocated.

- Reject allocation of an administratively disabled PMC.

Misc. code cleanups and refactoring. Improve a few comments.

Bring a working snapshot of hwpmc(4), its associated libraries, userland utilities
and documentation into -CURRENT.

Bump FreeBSD_version.

Reviewed by: alc, jhb (kernel changes)