Merge tag 'perf-tools-for-v6.19-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools

Pull perf tools updates from Namhyung Kim:
"Perf event/metric description:

Unify all

Merge tag 'perf-tools-for-v6.19-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools

Pull perf tools updates from Namhyung Kim:
"Perf event/metric description:

Unify all event and metric descriptions in JSON format. Now event
parsing and handling is greatly simplified by that.

From users point of view, perf list will provide richer information
about hardware events like the following.

$ perf list hw

List of pre-defined events (to be used in -e or -M):

legacy hardware:
branch-instructions
[Retired branch instructions [This event is an alias of branches]. Unit: cpu]
branch-misses
[Mispredicted branch instructions. Unit: cpu]
branches
[Retired branch instructions [This event is an alias of branch-instructions]. Unit: cpu]
bus-cycles
[Bus cycles,which can be different from total cycles. Unit: cpu]
cache-misses
[Cache misses. Usually this indicates Last Level Cache misses; this is intended to be used in conjunction with the
PERF_COUNT_HW_CACHE_REFERENCES event to calculate cache miss rates. Unit: cpu]
cache-references
[Cache accesses. Usually this indicates Last Level Cache accesses but this may vary depending on your CPU. This may include
prefetches and coherency messages; again this depends on the design of your CPU. Unit: cpu]
cpu-cycles
[Total cycles. Be wary of what happens during CPU frequency scaling [This event is an alias of cycles]. Unit: cpu]
cycles
[Total cycles. Be wary of what happens during CPU frequency scaling [This event is an alias of cpu-cycles]. Unit: cpu]
instructions
[Retired instructions. Be careful,these can be affected by various issues,most notably hardware interrupt counts. Unit: cpu]
ref-cycles
[Total cycles; not affected by CPU frequency scaling. Unit: cpu]

But most notable changes would be in the perf stat. On the right side,
the default metrics are better named and aligned. :)

$ perf stat -- perf test -w noploop

Performance counter stats for 'perf test -w noploop':

11 context-switches # 10.8 cs/sec cs_per_second
0 cpu-migrations # 0.0 migrations/sec migrations_per_second
3,612 page-faults # 3532.5 faults/sec page_faults_per_second
1,022.51 msec task-clock # 1.0 CPUs CPUs_utilized
110,466 branch-misses # 0.0 % branch_miss_rate (88.66%)
6,934,452,104 branches # 6781.8 M/sec branch_frequency (88.66%)
4,657,032,590 cpu-cycles # 4.6 GHz cycles_frequency (88.65%)
27,755,874,218 instructions # 6.0 instructions insn_per_cycle (89.03%)
TopdownL1 # 0.3 % tma_backend_bound
# 9.3 % tma_bad_speculation (89.05%)
# 9.7 % tma_frontend_bound (77.86%)
# 80.7 % tma_retiring (88.81%)

1.025318171 seconds time elapsed

1.013248000 seconds user
0.012014000 seconds sys

Deferred unwinding support:

With the kernel support (commit c69993ecdd4d: "perf: Support deferred
user unwind"), perf can use deferred callchains for userspace stack
trace with frame pointers like below:

$ perf record --call-graph fp,defer ...

This will be transparent to users when it comes to other commands like
perf report and perf script. They will merge the deferred callchains
to the previous samples as if they were collected together.

ARM SPE updates

- Extensive enhancements to support various kinds of memory
operations including GCS, MTE allocation tags, memcpy/memset,
register access, and SIMD operations.

- Add inverted data source filter (inv_data_src_filter) support to
exclude certain data sources.

- Improve documentation.

Vendor event updates:

- Intel: Updated event files for Sierra Forest, Panther Lake, Meteor
Lake, Lunar Lake, Granite Rapids, and others.

- Arm64: Added metrics for i.MX94 DDR PMU and Cortex-A720AE
definitions.

- RISC-V: Added JSON support for T-HEAD C920V2.

Misc:

- Improve pointer tracking in data type profiling. It'd give better
output when the variable is using container_of() to convert type.

- Annotation support for perf c2c report in TUI. Press 'a' key to
enter annotation view from cacheline browser window. This will show
which instruction is causing the cacheline contention.

- Lots of fixes and test coverage improvements!"

* tag 'perf-tools-for-v6.19-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (214 commits)
libperf: Use 'extern' in LIBPERF_API visibility macro
perf stat: Improve handling of termination by signal
perf tests stat: Add test for error for an offline CPU
perf stat: When no events, don't report an error if there is none
perf tests stat: Add "--null" coverage
perf cpumap: Add "any" CPU handling to cpu_map__snprint_mask
libperf cpumap: Fix perf_cpu_map__max for an empty/NULL map
perf stat: Allow no events to open if this is a "--null" run
perf test kvm: Add some basic perf kvm test coverage
perf tests evlist: Add basic evlist test
perf tests script dlfilter: Add a dlfilter test
perf tests kallsyms: Add basic kallsyms test
perf tests timechart: Add a perf timechart test
perf tests top: Add basic perf top coverage test
perf tests buildid: Add purge and remove testing
perf tests c2c: Add a basic c2c
perf c2c: Clean up some defensive gets and make asan clean
perf jitdump: Fix missed dso__put
perf mem-events: Don't leak online CPU map
perf hist: In init, ensure mem_info is put on error paths
...

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perf jevents: Add legacy-hardware and legacy-cache json

The legacy-hardware.json is added containing hardware events similarly
to the software.json file. A difference is that for the software PMU
th

perf jevents: Add legacy-hardware and legacy-cache json

The legacy-hardware.json is added containing hardware events similarly
to the software.json file. A difference is that for the software PMU
the name is known and matches sysfs. In the legacy-hardware.json no
Unit/PMU is specified for the events meaning default_core is used and
the events will appear for all core PMUs.

There are potentially 1216 legacy cache events, rather than list them
in a json file add a make_legacy_cache.py helper to generate them.

By using json for legacy hardware and cache events: descriptions of
the events can be added; events can be marked as deprecated, such as
those misleadingly named l2 (deprecated is also used to mark all
events that weren't previously displayed in perf list); and the name
lookup becomes case insensitive.

The C string encoding all the perf events and metrics is increased in
size by 123,499 bytes which will increase the perf binary size. Later
changes will remove hard coded event parsing for legacy hardware and
cache events, turning parsing overhead into a binary search during
event lookup.

That event descriptions are based off of those in perf_event_open man
page, credit to Vince Weaver <vincent.weaver@maine.edu>.

Tested-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: James Clark <james.clark@linaro.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>

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