pmc.h: bump PMC_VERSION_MINOR

Bump for the addition of PMC_OP_GETCAPS and the recently added Intel
CPUs.

Sponsored by: The FreeBSD Foundation

libpmc: Query hwpmc for caps

This change allows for fine-grained capabilities per counter index. This
is particularly useful for AMD where subclasses are not exposed to the
general PMC code, but oth

libpmc: Query hwpmc for caps

This change allows for fine-grained capabilities per counter index. This
is particularly useful for AMD where subclasses are not exposed to the
general PMC code, but other architectures also have asymmetric behaviors
when it comes to specific counter indices.

A new PMC_OP_GETCAPS op is added to the hwpmc(4) ioctl interface.

Reviewed by: mhorne
Sponsored by: Netflix
Pull Request: https://github.com/freebsd/freebsd-src/pull/2058

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hwpmc: Remove left over k7, xscale and p4 references pmc

Support for these processors was removed a few years ago, but a few
references remain that should be removed.

Sponsored by: Netflix
Reviewed

hwpmc: Remove left over k7, xscale and p4 references pmc

Support for these processors was removed a few years ago, but a few
references remain that should be removed.

Sponsored by: Netflix
Reviewed by: imp
Pull Request: https://github.com/freebsd/freebsd-src/pull/2039

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hwpmc: Initial support for AMD IBS

This patch adds support for AMD IBS. It adds a new class of performance
counter that cotains two events: ibs-fetch and ibs-op events. Unlike
most existing sampled

hwpmc: Initial support for AMD IBS

This patch adds support for AMD IBS. It adds a new class of performance
counter that cotains two events: ibs-fetch and ibs-op events. Unlike
most existing sampled events, IBS events provide a number of values
containing extra information regarding the sample. To support this we
use the existing callchain event, and introduce a new flag for multipart
payloads. The first 8 bytes of the pc_sample contains a header that
defines up to four payloads.

Sponsored by: Netflix

Reviewed by: imp,mhorne
Pull Request: https://github.com/freebsd/freebsd-src/pull/2022

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pmc: Import Intel Granite Rapids events

Reviewed by: mhorne
Sponsored by: Klara, Inc.
Obtained from: Intel perfmon (JSON event definitions)
Differential Revision: https://reviews.freebsd.org/D55081

pmc: Import Intel Granite Rapids events

Reviewed by: mhorne
Sponsored by: Klara, Inc.
Obtained from: Intel perfmon (JSON event definitions)
Differential Revision: https://reviews.freebsd.org/D55081
MFC after: 2 days

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pmc: add alderlaken model

This commit adds alderlaken CPU model to hwpmc/libpmc. JSON event
definitions are imported from Intel perfmon version 1.16.

Reviewed by: mhorne
MFC after: 1 week
Sponsored

pmc: add alderlaken model

This commit adds alderlaken CPU model to hwpmc/libpmc. JSON event
definitions are imported from Intel perfmon version 1.16.

Reviewed by: mhorne
MFC after: 1 week
Sponsored by: Stormshield
Differential Revision: https://reviews.freebsd.org/D49229

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pmc: add emerald rapids model

This commit adds emerald rapids CPU model to hwpmc/libpmc. JSON event
definitions are imported from Intel perfmon version 1.06.

Reviewed by: mhorne
MFC after: 1 week
S

pmc: add emerald rapids model

This commit adds emerald rapids CPU model to hwpmc/libpmc. JSON event
definitions are imported from Intel perfmon version 1.06.

Reviewed by: mhorne
MFC after: 1 week
Sponsored by: Stormshield
Differential Revision: https://reviews.freebsd.org/D49228

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pmc: remove last bits of AMD K7 CPU support

This includes event definitions from sys/pmc_events.h, definitions from
sys/pmc.h, and the man pages.

Reviewed by: jkoshy
Sponsored by: The FreeBSD Found

pmc: remove last bits of AMD K7 CPU support

This includes event definitions from sys/pmc_events.h, definitions from
sys/pmc.h, and the man pages.

Reviewed by: jkoshy
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D41275

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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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sys: Remove $FreeBSD$: two-line .h pattern

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

hwpmc(4): document debugging options

The debug options for hwpmc are not documented in detail anywhere, and
setting it up was error-prone the first time I had to figure it out (and
each time I've ha

hwpmc(4): document debugging options

The debug options for hwpmc are not documented in detail anywhere, and
setting it up was error-prone the first time I had to figure it out (and
each time I've had to remember it). Add some explanation of the required
options and describe the kern.hwpmc.debugflags sysctl format.

Reviewed by: emaste
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40545

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hwpmc: add error for HWPMC_DEBUG without KTR

The option is a no-op otherwise, but this is not necessarily obvious.
Failing the compile gives the user a hint.

Reviewed by: jkoshy, emaste
MFC after:

hwpmc: add error for HWPMC_DEBUG without KTR

The option is a no-op otherwise, but this is not necessarily obvious.
Failing the compile gives the user a hint.

Reviewed by: jkoshy, emaste
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40544

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hpwmc: add __pmcdbg_used annotation

For variables which are only used in PMCDBG* macros.

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

hpwmc: add __pmcdbg_used annotation

For variables which are only used in PMCDBG* macros.

Reviewed by: jkoshy, emaste
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D40288

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pmc: Bump major version for just-committed breaking changes

Reviewed by: jkoshy, mhorne, emaste
Differential Revision: https://reviews.freebsd.org/D40050

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 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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hwpmc: formatting of CPU and class lists

The end result is much more legible in both cases.

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

hwpmc: formatting of CPU and class lists

The end result is much more legible in both cases.

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39906

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hwpmc: trim MIPS CPU and class defs

MIPS is gone, and this is the last remaining bit in the pmc code.

Reviewed by: jkoshy, emaste
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differentia

hwpmc: trim MIPS CPU and class defs

MIPS is gone, and this is the last remaining bit in the pmc code.

Reviewed by: jkoshy, emaste
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39905

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hwpmc: trim obsolete Intel CPU and class defs

No functional change.

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D3

hwpmc: trim obsolete Intel CPU and class defs

No functional change.

Reviewed by: jkoshy
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39904

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pmc: Add a reminder to maintain documentation.

Approved by: gnn (mentor)
Differential Revision: https://reviews.freebsd.org/D39298

System wide and NUMA domain wide counters support. PMC classes for ARM DMC-620 and CMN-600.

Add support for system wide and NUMA domain wide counters support.
Add 3 new PMC classes for ARM DMC-620 a

System wide and NUMA domain wide counters support. PMC classes for ARM DMC-620 and CMN-600.

Add support for system wide and NUMA domain wide counters support.
Add 3 new PMC classes for ARM DMC-620 and CMN-600 controllers PMU.

Reviewed by: mhorne
Sponsored By: ARM
Sponsored By: Ampere Computing
Differential Revision: https://reviews.freebsd.org/D35342

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hwpmc: Increase thread priority while iterating CPUs.

This allows to profile already running high-priority threads, that
otherwise by blocking thread migration to respective CPUs blocked PMC
managem

hwpmc: Increase thread priority while iterating CPUs.

This allows to profile already running high-priority threads, that
otherwise by blocking thread migration to respective CPUs blocked PMC
management, i.e. profiling could start only when workload completed.

While there, return the thread to its original CPU after iterating
the list. Otherwise all threads using PMC end up on the last CPU.

MFC after: 1 month

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hwpmc: Add IDs for few more Intel Atom CPUs.

MFC after: 1 month

hwpmc: Add basic Intel Alderlake CPUs support.

The PMC subsystem is not designed for non-uniform CPU capabilities
(P/E-cores are different), but at least several working architectural
events like cp

hwpmc: Add basic Intel Alderlake CPUs support.

The PMC subsystem is not designed for non-uniform CPU capabilities
(P/E-cores are different), but at least several working architectural
events like cpu_clk_unhalted.thread_p should be better than nothing.

MFC after: 1 month

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