sys: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remov

sys: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/

Sponsored by: Netflix

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pmc: better distinguish pmu-events allocation path

Background:

The pm_ev field of struct pmc_op_pmcallocate and struct pmc
traditionally contains the index of the chosen event, corresponding to
the

pmc: better distinguish pmu-events allocation path

Background:

The pm_ev field of struct pmc_op_pmcallocate and struct pmc
traditionally contains the index of the chosen event, corresponding to
the __PMC_EVENTS array in pmc_events.h. This is a static list of events,
maintained by FreeBSD.

In the usual case, libpmc translates the user supplied event name
(string) into the pm_ev index, which is passed as an argument to the
allocation syscall. On the kernel side, the allocation method for the
relevant hwpmc class translates the given index into the event code that
will be written to an event selection register.

In 2018, a new source of performance event definitions was introduced:
the pmu-events json files, which are maintained by the Linux kernel. The
result was better coverage for newer Intel processors with a reduced
maintenance burden for libpmc/hwpmc. Intel and AMD CPUs were
unconditionally switched to allocate events from pmu-events instead of
the traditional scheme (959826ca1bb0a, 81eb4dcf9e0d).

Under the pmu-events scheme, the pm_ev field contains an index
corresponding to the selected event from the pmu-events table, something
which the kernel has no knowledge of. The configuration for the
performance counting registers is instead passed via class-dependent
fields (struct pmc_md_op_pmcallocate).

In 2021 I changed the allocation logic so that it would attempt to
pull from the pmu-events table first, and fall-back to the traditional
method (dfb4fb41166bc3). Later, pmu-events support for arm64 and power8
CPUs was added (28dd6730a5d6 and b48a2770d48b).

The problem that remains is that the pm_ev field is overloaded, without
a definitive way to determine whether the event allocation came from the
pmu-events table or FreeBSD's statically-defined PMC events. This
resulted in a recent fix, 21f7397a61f7.

Change:

To disambiguate these two supported but separate use-cases, add a new
flag, PMC_F_EV_PMU, to be set as part of the allocation, indicating that
the event index came from pmu-events.

This is useful in two ways:
1. On the kernel side, we can validate the syscall arguments better.
Some classes support only the traditional event scheme (e.g.
hwpmc_armv7), while others support only the pmu-events method (e.g.
hwpmc_core for Intel). We can now check for this. The hwpmc_arm64
class supports both methods, so the new flag supersedes the existing
MD flag, PM_MD_EVENT_RAW.

2. The flag will be tracked in struct pmc for the duration of its
lifetime, meaning it is communicated back to userspace. This allows
libpmc to perform the reverse index-to-event-name translation
without speculating about the meaning of the index value.

Adding the flag is a backwards-incompatible ABI change. We recently
bumped the major version of the hwpmc module, so this breakage is
acceptable.

Reviewed by: jkoshy
MFC after: 3 days
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40753

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hwpmc: on process exit, ensure that the owned log is closed

Tested by: pho (previous version)
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https:/

hwpmc: on process exit, ensure that the owned log is closed

Tested by: pho (previous version)
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D41521

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PMC_OP_CONFIGURELOG: cleanup logging process if aborting due to pm_flags

Reported by: pho
Fixes: 8e63e787abbd69d29e55e2e0b2aa0aa624339f3b
Sponsored by: The FreeBSD Foundation

sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

hwpmc: add 'flags' local to pmc_op_do_pmcallocate()

Similar to the other allocation parameters. No functional change.

MFC after: 3 days
Sponsored by: The FreeBSD Foundation

hwpmc: flatten conditional in pmc_process_exit()

Use a goto to clarify the control flow when there is no process
descriptor. This wins back a level of indentation.

No functional change intended.

R

hwpmc: flatten conditional in pmc_process_exit()

Use a goto to clarify the control flow when there is no process
descriptor. This wins back a level of indentation.

No functional change intended.

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40518

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hwpmc: split out PMC_OP_PMCRW

Split out the functional logic from the syscall handler into a helper
function. This keeps it separate from the syscall control-flow logic,
resulting in better readabil

hwpmc: split out PMC_OP_PMCRW

Split out the functional logic from the syscall handler into a helper
function. This keeps it separate from the syscall control-flow logic,
resulting in better readability overall. It also wins back a level of
indentation.

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40294

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hwpmc: split out PMC_OP_PMCRELEASE

Split out the functional logic from the syscall handler into a helper
function. This keeps it separate from the syscall control-flow logic,
resulting in better rea

hwpmc: split out PMC_OP_PMCRELEASE

Split out the functional logic from the syscall handler into a helper
function. This keeps it separate from the syscall control-flow logic,
resulting in better readability overall. It also wins back a level of
indentation.

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40293

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hwpmc: split out PMC_OP_PMCALLOCATE

Split out the large chunk of functional logic from the syscall handler
into a helper function. This keeps it separate from the syscall
control-flow logic, resulti

hwpmc: split out PMC_OP_PMCALLOCATE

Split out the large chunk of functional logic from the syscall handler
into a helper function. This keeps it separate from the syscall
control-flow logic, resulting in better readability overall. It also
wins back a level of indentation.

Flip the return values of the pmc_can_allocate_row() and
pmc_can_allocate_rowindex() functions to boolean types, like their
naming implies. We weren't actually using the error codes they were
returning.

While here, make some small style cleanups. No functional change
intended.

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40292

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hwpmc: split out PMC_OP_PMCATTACH/PMC_OP_PMCDETACH

Begin splitting out the large chunks of functional logic from the
syscall handler into separate helper functions. This keeps it separate
from the s

hwpmc: split out PMC_OP_PMCATTACH/PMC_OP_PMCDETACH

Begin splitting out the large chunks of functional logic from the
syscall handler into separate helper functions. This keeps it separate
from the syscall control-flow logic, resulting in better readability
overall. It also wins back a level of indentation.

For this and the similar changes to follow, try to keep copyin() and
copyout() calls outside of the helper functions. The changes are
intended to have no functional impact, but do address style issues.

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40291

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hwpmc: split out PMC_FN_PROCESS_EXEC

Move the functionality into a separate helper function. All other
actions in pmc_hook_handler() already have this.

While here make some small style improvements

hwpmc: split out PMC_FN_PROCESS_EXEC

Move the functionality into a separate helper function. All other
actions in pmc_hook_handler() already have this.

While here make some small style improvements. Restructure one for loop.

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40333

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hwpmc_mod.c: misc style cleanup

Everything else I found worthy of adjustment.

- Order local variable declarations per style(9)
- Make use of __unused annotations rather than cast to void
- Remov

hwpmc_mod.c: misc style cleanup

Everything else I found worthy of adjustment.

- Order local variable declarations per style(9)
- Make use of __unused annotations rather than cast to void
- Remove unnecessary casts
- Add (void) casts to PMC class methods where the return value is
ignored
- A couple instances of reordering statements for clarity
- Prefer bool type where applicable
- unsigned int -> u_int
- Use uintmax_t/%j in printf calls
- Formatting of comments

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40517

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hwpmc_mod.c: prototype style

Improve alphabetical organization, grouping, and whitespace.

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://

hwpmc_mod.c: prototype style

Improve alphabetical organization, grouping, and whitespace.

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40516

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hwpmc_mod.c: conditional and loop style

- Explicitly check the value in conditional statements, per style(9)
- Add braces around more loops and conditionals, wherever it appears
(to me) to aid

hwpmc_mod.c: conditional and loop style

- Explicitly check the value in conditional statements, per style(9)
- Add braces around more loops and conditionals, wherever it appears
(to me) to aid legibility
- Expand some assignments within if statements
- Fix formatting around list-type FOREACH macros

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40515

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hwpmc_mod.c: whitespace style cleanup

Handle a few things related to spacing:
- Remove redundant/superfluous blank lines (and add a couple where
helpful)
- Add spacing around binary operators

hwpmc_mod.c: whitespace style cleanup

Handle a few things related to spacing:
- Remove redundant/superfluous blank lines (and add a couple where
helpful)
- Add spacing around binary operators
- Remove spacing after casts and before goto labels
- Adjustments for line width of 80 chars
- Tab/space character issues

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40514

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hwpmc_mod.c: return statement style

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40513

pmc: Rework PROCEXEC event to support PIEs

Currently the PROCEXEC event only reports a single address, entryaddr,
which is the entry point of the interpreter in the typical dynamic case,
and used so

pmc: Rework PROCEXEC event to support PIEs

Currently the PROCEXEC event only reports a single address, entryaddr,
which is the entry point of the interpreter in the typical dynamic case,
and used solely to calculate the base address of the interpreter. For
PDEs this is fine, since the base address is known from the program
headers, but for PIEs the base address varies at run time based on where
the kernel chooses to load it, and so pmcstat has no way of knowing the
real address ranges for the executable. This was less of an issue in the
past since PIEs were rare, but now they're on by default on 64-bit
architectures it's more of a problem.

To solve this, pass through what was picked for et_dyn_addr by the
kernel, and use that as the offset for the executable's start address
just as is done for everything in the kernel. Since we're changing this
interface, sanitise the way we determine the interpreter's base address
by passing it through directly rather than indirectly via the entry
point and having to subtract off whatever the ELF header's e_entry is
(and anything that wants the entry point in future can still add that
back on as needed; this merely changes the interface to directly provide
the underlying variables involved).

This will be followed up by a bump to the pmc major version.

Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D39595

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pmc: Provide full path to modules from kernel linker

This unifies the user object and kernel module paths in libpmcstat,
allows modules loaded from non-standard locations (e.g. from a user's
home di

pmc: Provide full path to modules from kernel linker

This unifies the user object and kernel module paths in libpmcstat,
allows modules loaded from non-standard locations (e.g. from a user's
home directory when testing) to be found and, since buffer is what all
the warnings here use (they were never updated when buffer_modules were
added to pick based on where the file was found) has the side-effect of
ensuring the messages are correct.

This includes obsoleting the now-superfluous -k option in pmcstat.

This change breaks the hwpmc ABI and will be followed by a bump to the
pmc major version.

Reviewed by: jhb, jkoshy, mhorne
Differential Revision: https://reviews.freebsd.org/D40048

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pmc: Initialise and check the pm_flags field for CONFIGURELOG

Whilst the former is not breaking, the latter is, and so this will be
followed by a bump to the pmc major version. This will allow the f

pmc: Initialise and check the pm_flags field for CONFIGURELOG

Whilst the former is not breaking, the latter is, and so this will be
followed by a bump to the pmc major version. This will allow the flags
to actually be usable in future, as otherwise we cannot distinguish
uninitialised stack junk from a deliberately-initialised value.

Reviewed by: jhb, mhorne
Differential Revision: https://reviews.freebsd.org/D40049

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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

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

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hwpmc: pass pmc pointer to more class methods

In many cases this avoids an extra lookup, since the callers always have
pm at hand. We can also eliminate several assertions, mostly for pm !=
NULL. Th

hwpmc: pass pmc pointer to more class methods

In many cases this avoids an extra lookup, since the callers always have
pm at hand. We can also eliminate several assertions, mostly for pm !=
NULL. The class methods are an internal interface, and the callers
already handle such a scenario. No functional change intended.

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39915

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hwpmc: remove stub pmd_switch_{in,out} methods

Most platforms (non-x86) don't require these methods and implement stub
versions. If we initialize the pmc_mdep structure to always point to the
generi

hwpmc: remove stub pmd_switch_{in,out} methods

Most platforms (non-x86) don't require these methods and implement stub
versions. If we initialize the pmc_mdep structure to always point to the
generic versions, then we can purge the duplicate stubs.

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39913

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hwpmc: remove pmd_pcpu_{init,fini} callbacks

These are unused on all platforms.

Reviewed by: jkoshy, emaste
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://re

hwpmc: remove pmd_pcpu_{init,fini} callbacks

These are unused on all platforms.

Reviewed by: jkoshy, emaste
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39912

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Fix unused variable warnings in hwpmc_mod.c

With clang 15, the following -Werror warnings are produced:

sys/dev/hwpmc/hwpmc_mod.c:4805:6: error: variable 'nfree' set but not used [-Werror,-Wunu

Fix unused variable warnings in hwpmc_mod.c

With clang 15, the following -Werror warnings are produced:

sys/dev/hwpmc/hwpmc_mod.c:4805:6: error: variable 'nfree' set but not used [-Werror,-Wunused-but-set-variable]
int nfree;
^
sys/dev/hwpmc/hwpmc_mod.c:4804:6: error: variable 'ncallchains' set but not used [-Werror,-Wunused-but-set-variable]
int ncallchains;
^

The 'nfree' and 'ncallchains' variables were used in KASSERTs, but these
were removed due to refactoring in d9f1b8dbf29d. Remove the variables
since they no longer serve any purpose.

MFC after: 3 days

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