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 r269525:
Return 0 for the PPID of threads in process 0, as process 0 doesn't have a
parent process.

MFC r256571:
Add a function, memstr, which can be used to convert a buffer of
null-separated strings to a single string. This can be used to print the
full arguments of a process using execsnoop (from the DTrace toolkit) or
with the following one-liner:

dtrace -n 'syscall::execve:return {trace(curpsinfo->pr_psargs);}'

Note that this relies on the process arguments being cached via the struct
proc, which means that it will not work for argvs longer than
kern.ps_arg_cache_limit. However, the following rather non-portable
script can be used to extract any argv at exec time:

fbt::kern_execve:entry
{
printf("%s", memstr(args[1]->begin_argv, ' ',
args[1]->begin_envv - args[1]->begin_argv));
}

The debug.dtrace.memstr_max sysctl limits the maximum argument size to
memstr().

MFC r268290:
Merge from OpenSolaris (24-Jul-2010):

6679140 asymmetric alloc/dealloc activity can induce dynamic variable drops
6679193 dtrace_dynvar walker produces flood of dtrace_dynhash_sink

This finishes a set of merges from the older OpenSolaris releases.
Still the FreeBSD port has many differences that are difficult to
account for but that seems normal given that the kernels are different.

Obtained from: OpenSolaris (through Illumos)

MFC 267929, 267937, 267939, 267940, 267941, 267942, 267987, 268006:

2915 DTrace in a zone should see "cpu", "curpsinfo", et al
2916 DTrace in a zone should be able to access fds[]
2917 DTrace in a zone should have limited provider access
4477 DTrace should speak JSON
Add stubs for CTF functions which are not yet implemented.
4474 DTrace Userland CTF Support
4475 DTrace userland Keyword
4476 DTrace tests should be better citizens
4479 pid provider types
4480 dof emulation is missing checks
4471 DTrace count() with histogram
4472 DTrace full width distribution histograms
4473 DTrace frequency trails

MFC r268130, r268224, r268230, r268231:

Various DTrace Merges from OpenSolaris/Illumos:

15-Sep-2008:
6735480 race between probe enabling and provider registration

20-Apr-2008:
6822482 DOF validation needs to handle loadable sections flagged as unloadable

22-Apr-2009:
6823388 DTrace ioctl handlers must validate all structure members

30-Jun-2009:
6851093 system drops to kmdb with anonymous dtrace probes + kmdb

Obtained from: OpenSolaris

MFC r268125:

Small merges from OpenSolaris:

These have no effect on FreeBSD, in fact they are ifdef'ed,
but make easier future merges:

6699767 panic in spec_open()

6718877 crgetzoneid() use can cause problems when forking processes with
USDT providers in a non global zone

MFC r262329:
Define the KM_NORMALPRI flag for kmem_alloc(), as it is used in some
upstream DTrace code.

MFC r262330:
1452 DTrace buffer autoscaling should be less violent

illumos/illumos-gate@6fb4854bed54ce82bd8610896b64ddebcd4af706

MFC r262665:
Expose a few DTrace parameters as sysctls under kern.dtrace and add
descriptions for several existing sysctls.

PR: 187027

MFC r264040:

4248 dtrace(1M) should never create DOF with empty probes section
4249 Only probes from the first DTrace object file will be included

Illumos Revision: 4a20ab41aadcb81c53e72fc65886e964e9add59

Reference:
https://www.illumos.org/issues/4248
https://www.illumos.org/issues/4249

Obtained from: Illumos

MFC r262596:
4478 dtrace_dof_maxsize is far too small

illumos/illumos-gate@d339a29bb4765c4b6883a935cf69b669cd05bca0

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

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

Initialize and free the DTrace taskqueue in the dtrace module load/unload
handlers rather than in the dtrace device open/close methods. The current
approach can cause a panic if the device is closed which the taskqueue
thread is active, or if a kernel module containing a provider is unloaded
while retained enablings are present and the dtrace device isn't opened.

Submitted by: gibbs (original version)
Reviewed by: gibbs
Approved by: re (glebius)
MFC after: 2 weeks

Rename the kld_unload event handler to kld_unload_try, and add a new
kld_unload event handler which gets invoked after a linker file has been
successfully unloaded. The kld_unload and kld_load event handlers are now
invoked with the shared linker lock held, while kld_unload_try is invoked
with the lock exclusively held.

Convert hwpmc(4) to use these event handlers instead of having
kern_kldload() and kern_kldunload() invoke hwpmc(4) hooks whenever files are
loaded or unloaded. This has no functional effect, but simplifes the linker
code somewhat.

Reviewed by: jhb

Use kld_{load,unload} instead of mod_{load,unload} for the linker file load
and unload event handlers added in r254266.

Reported by: jhb
X-MFC with: r254266

FreeBSD's DTrace implementation has a few problems with respect to handling
probes declared in a kernel module when that module is unloaded. In
particular,

* Unloading a module with active SDT probes will cause a panic. [1]
* A module's (FBT/SDT) probes aren't destroyed when the module is unloaded;
trying to use them after the fact will generally cause a panic.

This change fixes both problems by porting the DTrace module load/unload
handlers from illumos and registering them with the corresponding
EVENTHANDLER(9) handlers. This allows the DTrace framework to destroy all
probes defined in a module when that module is unloaded, and to prevent a
module unload from proceeding if some of its probes are active. The latter
problem has already been fixed for FBT probes by checking lf->nenabled in
kern_kldunload(), but moving the check into the DTrace framework generalizes
it to all kernel providers and also fixes a race in the current
implementation (since a probe may be activated between the check and the
call to linker_file_unload()).

Additionally, the SDT implementation has been reworked to define SDT
providers/probes/argtypes in linker sets rather than using SYSINIT/SYSUNINIT
to create and destroy SDT probes when a module is loaded or unloaded. This
simplifies things quite a bit since it means that pretty much all of the SDT
code can live in sdt.ko, and since it becomes easier to integrate SDT with
the DTrace framework. Furthermore, this allows FreeBSD to be quite flexible
in that SDT providers spanning multiple modules can be created on the fly
when a module is loaded; at the moment it looks like illumos' SDT
implementation requires all SDT probes to be statically defined in a single
kernel table.

PR: 166927, 166926, 166928
Reported by: davide [1]
Reviewed by: avg, trociny (earlier version)
MFC after: 1 month

Hide references to mod_lock. In FreeBSD it is always acquired with the
provider lock held, so its use has no effect.

Bring back part of r249367 by adding DTrace's temporal option, which allows
users to guarantee that the output of DTrace scripts will be time-ordered.
This option is enabled by adding the line

#pragma D option temporal

to the beginning of a script, or by adding '-x temporal' to the arguments of
dtrace(1).

This change fixes a bug in the original port of the temporal option. This
bug was causing some assertions to fail, so they had been disabled; in this
revision the assertions are working properly and are enabled.

The DTrace version number has been bumped from 1.9.0 to 1.9.1 to reflect
the language change that's being introduced.

This change corresponds to part of illumos-gate commit e5803b76927480:
3021 option for time-ordered output from dtrace(1M)

Reviewed by: pfg
Obtained from: illumos
MFC after: 1 month

DTrace: Revert r249367

The following change from illumos brought caused DTrace to
pause in an interactive environment:

3026 libdtrace should set LD_NOLAZYLOAD=1 to help the pid provider

This was not detected during testing because it doesn't
affect scripts.

We shouldn't be changing the environment, especially since the
LD_NOLAZYLOAD option doesn't apply to our (GNU) ld.
Unfortunately the change from upstream was made in such a way
that it is very difficult to separate this change from the
others so, at least for now, it's better to just revert
everything.

Reference:
https://www.illumos.org/issues/3026

Reported by: Navdeep Parhar and Mark Johnston

DTrace: option for time-ordered output

Merge changes from illumos:

3021 option for time-ordered output from dtrace(1M)
3022 DTrace: keys should not affect the sort order when sorting by value
3023 it should be possible to dereference dynamic variables
3024 D integer narrowing needs some work
3025 register leak in D code generation
3026 libdtrace should set LD_NOLAZYLOAD=1 to help the pid provider

This brings yet another feature implemented in upstream DTrace.
A complete description is available here:
http://dtrace.org/blogs/ahl/2012/07/28/my-new-dtrace-favorite/

This change bumps the DT_VERS_* number to 1.9.1 in
accordance to what is done in illumos.

This change was somewhat complicated because upstream is mixed many
changes in an individual commit and some of the tests don't really
apply to us.

There are also appear to be differences in timestamping with Solaris
so we had to workaround some assertions making sure no regression
happened.

Special thanks to Fabian Keil for changes and testing.

Illumos Revisions: 13758:23432da34147

Reference:
https://www.illumos.org/issues/3021
https://www.illumos.org/issues/3022
https://www.illumos.org/issues/3023
https://www.illumos.org/issues/3024
https://www.illumos.org/issues/3025
https://www.illumos.org/issues/1694

Tested by: Fabian Keil
Obtained from: Illumos
MFC after: 1 months

Dtrace: enablings on defunct providers prevent providers from unregistering

Merge change from illumos:

1368 enablings on defunct providers prevent providers from unregistering

We try to address some underlying differences between the Solaris
and FreeBSD implementations: dtrace_attach() / dtrace_detach() are
currently unimplemented in FreeBSD but the new code from illumos
makes use of taskq so some adaptations were made to dtrace_open()
and dtrace_close() to handle them appropriately.

Illumos Revision: r13430:8e6add739e38

Reference:
https://www.illumos.org/issues/1368

Reviewed by: gnn
Tested by: Fabian Keil
Obtained from: Illumos
MFC after: 3 weeks

Dtrace: dtrace.c erroneously checks for memory alignment on amd64.

Merge change from illumos:

3511 dtrace.c erroneously checks for memory alignment on amd64

Illumos Revision: c93cc65

Reference:
https://www.illumos.org/issues/3511

Obtained from: Illumos
MFC after: 3 weeks

Dtrace: Add SUN MDB-like type-aware print() action.

Merge change from illumos:

1694 Add type-aware print() action

This is a very nice feature implemented in upstream Dtrace.
A complete description is available here:
http://dtrace.org/blogs/eschrock/2011/10/26/your-mdb-fell-into-my-dtrace/

This change bumps the DT_VERS_* number to 1.9.0 in
accordance to what is done in illumos.

While here also include some minor cleanups to ease further merging
and appease clang with a fix by Fabian Keil.

Illumos Revisions: 13501:c3a7090dbc16
13483:f413e6c5d297

Reference:
https://www.illumos.org/issues/1560
https://www.illumos.org/issues/1694

Tested by: Fabian Keil
Obtained from: Illumos
MFC after: 1 month

Dtrace: add toupper()/tolower() and enhancements to lltostr().

Merge changes from illumos:

1451 DTrace needs toupper()/tolower() subroutines
1457 lltostr() D subroutine should take an optional base

This change bumps the DT_VERS_* number to 1.8.1 in
accordance to what is done in illumos.

The test suite we currently include is outdated and
doesnt support some updates in tst.subr.d which had to
be left out for now.

Illumos Revisions: r13458 5e394d8db762
r13459 c3454574dd1a

Reference:
https://www.illumos.org/issues/1451
https://www.illumos.org/issues/1457

Tested by: Fabian Keil
Obtained from: Illumos
MFC after: 1 month

Dtrace: add optional size argument to tracemem().

Merge change from illumos:

1455 DTrace tracemem() should take an optional size argument

Our local enhancements to dt_print_bytes were equivalent to
those in illumos but we made it match the illumos version
to ease further code merges.

For now leave out tst.smallsize.d and tst.smallsize.d.out
since those don't seem to work cleanly on FreeBSD.

This change bumps the DT_VERS_* number to 1.7.1 in accordance
to what is done in illumos.

Illumos Revision: 13457:571b0355c2e3

Reference:
https://www.illumos.org/issues/1455

Tested by: Fabian Keil
Obtained from: Illumos
MFC after: 1 month

Implement DTrace for PowerPC. This includes both 32-bit and 64-bit.

There is one known issue: Some probes will display an error message along the
lines of: "Invalid address (0)"

I tested this with both a simple dtrace probe and dtruss on a few different
binaries on 32-bit. I only compiled 64-bit, did not run it, but I don't expect
problems without the modules loaded. Volunteers are welcome.

MFC after: 1 month

Use a proper destructor function.

When calling a revoke(2) on a dtrace device, dtrace_close() could be
called, even if threads are still stuck in the device. Defer the actual
deallocation of datastructures to the cdevpriv destructor.

While there, remove the unneeded D_TRACKCLOSE and D_NEEDMINOR flags. For
the helper device, we never need it. For the regular dtrace devices, we
only need these flags on FreeBSD pre-8.

MFC after: 1 month

Streamline use of cdevpriv and correct some corner cases.

1) It is not useful to call "devfs_clear_cdevpriv()" from
"d_close" callbacks, hence for example read, write, ioctl and
so on might be sleeping at the time of "d_close" being called
and then then freed private data can still be accessed.
Examples: dtrace, linux_compat, ksyms (all fixed by this patch)

2) In sys/dev/drm* there are some cases in which memory will
be freed twice, if open fails, first by code in the open
routine, secondly by the cdevpriv destructor. Move registration
of the cdevpriv to the end of the drm open routines.

3) devfs_clear_cdevpriv() is not called if the "d_open" callback
registered cdevpriv data and the "d_open" callback function
returned an error. Fix this.

Discussed with: phk
MFC after: 2 weeks

Bump dtrace_helper_actions_max from 32 to 128

Dave Pacheco from Joyent (and Dtrace.org) bumped the cap to 1024 but,
according to his blog, 128 is the recommended minimum.

For now bump it safely to 128 although we may have to bump it further
if there is demand in the future.

Reference:

http://www.illumos.org/issues/2558
http://dtrace.org/blogs/dap/2012/01/50/where-does-your-node-program-spend-its-time/

Bring llquantize support into Dtrace.

Bryan Cantrill implemented the equivalent of semi-log graph
paper for Dtrace so llquantize will use one logarithmic and
one linear scale.

Special thanks to Mark Peek for providing fix to an
assertion and to Fabian Keill for testing the port.

Illumos Revision: 13355:15b74a2a9a9d

Reference:
https://www.illumos/issues/905

Obtained from: Illumos
Tested by: Fabian Keill, mp
MFC after: 4 days

Implement the D "cpu" variable, which returns curcpu. I have chosen not
to follow the example of OpenSolaris and its descendants, which implemented
cpu as an inline that took a value out of curthread. At certain points in
the FreeBSD scheduler curthread->td_oncpu will no longer be valid (in
particukar, just before the thread gets descheduled) so instead I have
implemented this as its own built-in variable.

Sponsored by: Sandvine Inc.
MFC after: 1 week

Add MIPS support to cddl/contrib part:

- header and stub .c file for fasttrap module. It's not supported on
MIPS yet, but there is no way to disable support completely
- Do as amd64 trying to limit allocated memory

Revert the approach for skipping lockstat_probe_func call when doing
lock_success/lock_failure, introduced in r228424, by directly skipping
in dtrace_probe.

This mainly helps in avoiding namespace pollution and thus lockstat.h
dependency by systm.h.

As an added bonus, this also helps in MFC case.
Reviewed by: avg
MFC after: 3 months (or never)
X-MFC: r228424

In order to maximize the re-usability of kernel code in user space this
patch modifies makesyscalls.sh to prefix all of the non-compatibility
calls (e.g. not linux_, freebsd32_) with sys_ and updates the kernel
entry points and all places in the code that use them. It also
fixes an additional name space collision between the kernel function
psignal and the libc function of the same name by renaming the kernel
psignal kern_psignal(). By introducing this change now we will ease future
MFCs that change syscalls.

Reviewed by: rwatson
Approved by: re (bz)

Fix two bugs in DTrace:
* when the process exits, remove the associated USDT probes
* when the process forks, duplicate the USDT probes.

Sponsored by: The FreeBSD Foundation

Kernel DTrace support for:
o uregs (sson@)
o ustack (sson@)
o /dev/dtrace/helper device (needed for USDT probes)

The work done by me was:
Sponsored by: The FreeBSD Foundation

Update several places that iterate over CPUs to use CPU_FOREACH().

Add the OpenSolaris dtrace lockstat provider. The lockstat provider
adds probes for mutexes, reader/writer and shared/exclusive locks to
gather contention statistics and other locking information for
dtrace scripts, the lockstat(1M) command and other potential
consumers.

Reviewed by: attilio jhb jb
Approved by: gnn (mentor)

Merge latest DTrace changes from Perforce.

Disable use of the user credentials until there is code to set the levels
that DTrace uses.

This fixes a bug that would have affected kernels built with MAC and all
kernels built after the mpsafetty integration.

The bug will be apparent in RELENG7 on MAC kernels.

Reported by: kan

Replace all calls to minor() with dev2unit().

After I removed all the unit2minor()/minor2unit() calls from the kernel
yesterday, I realised calling minor() everywhere is quite confusing.
Character devices now only have the ability to store a unit number, not
a minor number. Remove the confusion by using dev2unit() everywhere.

This commit could also be considered as a bug fix. A lot of drivers call
minor(), while they should actually be calling dev2unit(). In -CURRENT
this isn't a problem, but it turns out we never had any problem reports
related to that issue in the past. I suspect not many people connect
more than 256 pieces of the same hardware.

Reviewed by: kib

Add calls to callout_drain() to ensure the callouts are flushed before
we free memory from underneath them.

This fixes an occasional panic I've been seeing in softclock() where a bad
pointer would be encountered when pushing DTrace hard.

Don't enforce unique device minor number policy anymore.

Except for the case where we use the cloner library (clone_create() and
friends), there is no reason to enforce a unique device minor number
policy. There are various drivers in the source tree that allocate unr
pools and such to provide minor numbers, without using them themselves.

Because we still need to support unique device minor numbers for the
cloner library, introduce a new flag called D_NEEDMINOR. All cdevsw's
that are used in combination with the cloner library should be marked
with this flag to make the cloning work.

This means drivers can now freely use si_drv0 to store their own flags
and state, making it effectively the same as si_drv1 and si_drv2. We
still keep the minor() and dev2unit() routines around to make drivers
happy.

The NTFS code also used the minor number in its hash table. We should
not do this anymore. If the si_drv0 field would be changed, it would no
longer end up in the same list.

Approved by: philip (mentor)

Merge a recent change from the OpenSolaris source tree.
(Don't ask for a vendor import of this yet, we're in the early days of svn)

Instead of using cyclic timers to call the state clean and deadman callbacks,
use a callout on FreeBSD to avoid the deadlock on FreeBSD due to trying to
send interprocessor interrupts with interrupts disabled.

Reported by: ps, jhb, peter, thompsa

Comment out the code that breaks with invariants. This is stuff that is
still WIP along with the lockstat provider, so there is no harm leaving
it out for now.

FreeBSD changes to vendor source.

This commit was generated by cvs2svn to compensate for changes in r179193,
which included commits to RCS files with non-trunk default branches.

Vendor import of the src/sys OpenSolaris bits for DTrace.