linux-toradex.git/tools/perf/pmu-events/Build, branch master

perf build: fix "argument list too long" in second location

2026-04-14T06:22:16+00:00

Turns out that displaying "RM $^" via quiet_cmd_rm can also upset the
shell and cause it to display "argument list too long".

Trying to quote $^ doesn't help.

In the end, *not* displaying the (potentially long) list of files is
probably the right thing to do for a "quiet" message, anyway. Instead,
let's display a count of how many files were removed. There is always
V=1 if more detail is required.

  TEST    linux/tools/perf/pmu-events/metric_test.log
  RM      ...634 orphan file(s)...
  LD      linux/tools/perf/util/perf-util-in.o

Also move the comment regarding xargs before the rule, so it doesn't
show up in the build output.

Signed-off-by: Markus Mayer 
Reviewed-by: James Clark 
Signed-off-by: Namhyung Kim

perf build: Prevent "argument list too long" error

2026-03-04T14:22:31+00:00

Due to a recent change, building perf may result in a build error when
it is trying to "prune orphans".

The file list passed to "rm" may exceed what the shell can handle.

The build will then abort with an error like this:

    TEST    [...]/arm64/build/linux-custom/tools/perf/pmu-events/metric_test.log
  make[5]: /bin/sh: Argument list too long
  make[5]: *** [pmu-events/Build:217: prune_orphans] Error 127
  make[5]: *** Waiting for unfinished jobs....
  make[4]: *** [Makefile.perf:773: [...]/tools/perf/pmu-events/pmu-events-in.o] Error 2
  make[4]: *** Waiting for unfinished jobs....
  make[3]: *** [Makefile.perf:289: sub-make] Error 2

Processing the arguments via "xargs", instead of passing the list of
files directly to "rm" via the shell, prevents this issue.

Fixes: 36a1b0061a584430 ("perf build: Reduce pmu-events related copying and mkdirs")
Reviewed-by: Ian Rogers 
Signed-off-by: Markus Mayer 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Signed-off-by: Arnaldo Carvalho de Melo

perf build: Reduce pmu-events related copying and mkdirs

2026-02-06T22:11:36+00:00

When building to an output directory the previous code would remove
files and then copy the source files over.

Each source file copy would have a rule to make its directory. All JSON
for every architecture was considered a source file.

This led to unnecessary copying as a file would be deleted and then the
same file copied again, unnecessary directory making, and copying of
files not used in the build.

A side-effect would be a lot of build messages.

This change makes it so that all computed output files are created and
then compared to all files in the OUTPUT directory.

By filtering out the files that would be copied, unnecessary files can
be determined and then deleted - note, this is a phony target which
would remake the pmu-events.c if always depended upon, and so the
dependency is conditional on there being files to remove.

This has some overhead as the $(OUTPUT)/pmu-events is "find" over rather
than just "rm -fr", but the savings from unnecessary copying, etc.
should make up for this new make overhead.

The copy target just does copying but has a dependency on the directory
it needs being built, avoiding repetitive mkdirs.

The source files for copying only consider the JEVENTS_ARCH unless the
JEVENTS_ARCH is all.

The metric JSON is only generated if appropriate, rather than always
being generated and jevents.py deciding whether or not to use the files.

The mypy and pylint targets are fixed as variable names had changed but
the rules not updated.

The line count of a build with "make -C tools/perf O=/tmp/perf clean all"
prior to this change was 2181 lines, after this change it is 1596
lines.

This is a reduction of 585 lines or about 27%.

The generated pmu-events.c for JEVENTS_ARCH "x86" and "all" were
validated as being identical after this change.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: Leo Yan 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Signed-off-by: Arnaldo Carvalho de Melo

perf jevents: Add cycles breakdown metric for arm64/AMD/Intel

2026-01-28T18:18:46+00:00

Breakdown cycles to user, kernel and guest. Add a common_metrics.py
file for such metrics.

Signed-off-by: Ian Rogers 
Tested-by: Thomas Falcon 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Benjamin Gray 
Cc: Caleb Biggers 
Cc: Edward Baker 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jing Zhang 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Leo Yan 
Cc: Namhyung Kim 
Cc: Perry Taylor 
Cc: Peter Zijlstra 
Cc: Sandipan Das 
Cc: Weilin Wang 
Cc: Xu Yang 
Signed-off-by: Arnaldo Carvalho de Melo

perf jevents: Add load event JSON to verify and allow fallbacks

2026-01-28T18:18:44+00:00

Add a LoadEvents function that loads all event JSON files in a
directory.

In the Event constructor ensure all events are defined in the event JSON
except for legacy events like "cycles".

If the initial event isn't found then legacy_event1 is used, and if that
isn't found legacy_event2 is used.

This allows a single Event to have multiple event names as models will
often rename the same event over time. If the event doesn't exist an
exception is raised.

So that references to metrics can be added, add the MetricRef
class. This doesn't validate as an event name and so provides an
escape hatch for metrics to refer to each other.

Signed-off-by: Ian Rogers 
Tested-by: Thomas Falcon 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Benjamin Gray 
Cc: Caleb Biggers 
Cc: Edward Baker 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jing Zhang 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Leo Yan 
Cc: Namhyung Kim 
Cc: Perry Taylor 
Cc: Peter Zijlstra 
Cc: Sandipan Das 
Cc: Weilin Wang 
Cc: Xu Yang 
Signed-off-by: Arnaldo Carvalho de Melo

perf jevents: Build support for generating metrics from python

2026-01-28T18:18:44+00:00

Generate extra-metrics.json and extra-metricgroups.json from python
architecture specific scripts. The metrics themselves will be added in
later patches.

If a build takes place in tools/perf/ then extra-metrics.json and
extra-metricgroups.json are generated in that directory and so added
to .gitignore.

If there is an OUTPUT directory then the tools/perf/pmu-events/arch
files are copied to it so the generated extra-metrics.json and
extra-metricgroups.json can be added/generated there.

Signed-off-by: Ian Rogers 
Tested-by: Thomas Falcon 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Benjamin Gray 
Cc: Caleb Biggers 
Cc: Edward Baker 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jing Zhang 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Leo Yan 
Cc: Namhyung Kim 
Cc: Perry Taylor 
Cc: Peter Zijlstra 
Cc: Sandipan Das 
Cc: Weilin Wang 
Cc: Xu Yang 
Signed-off-by: Arnaldo Carvalho de Melo

perf jevents: Handle deleted JSONS in out of source builds

2026-01-28T00:19:36+00:00

Make the source folders a dependency for the generated folder root so
that whenever a file is deleted from the source it will force a new
fresh copy of all the JSON files and avoid stale deleted files.

JSON_DIRS_OUTPUT_ROOT needs to be a dependency of LEGACY_CACHE_JSON so
that the root folder doesn't get cleaned after the legacy JSON is
generated. But this is a no-op with in-source builds as
JSON_DIRS_OUTPUT_ROOT is unset.

JSON_DIRS is added as a dependency of PMU_EVENTS_C which also forces a
re-build for in source builds when JSON files are deleted. This could
have also resulted in stale builds, but never a broken one.

Closes: https://lore.kernel.org/linux-next/aW5XSAo88_LBPSYI@sirena.org.uk/
Fixes: 4bb55de4ff03db3e ("perf jevents: Support copying the source json files to OUTPUT")
Reported-by: Mark Brown 
Signed-off-by: James Clark 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Signed-off-by: Arnaldo Carvalho de Melo

perf jevents: Suppress circular dependency warnings

2025-10-21T04:11:49+00:00

When doing an in source build, $(OUTPUT) is empty so the rule has the
same input and output file. Suppress the warning by only adding the rule
when doing an out of source build. The same condition already exists for
the clean rule for json files.

This fixes the following warnings:

  make[3]: Circular pmu-events/arch/nds32/mapfile.csv <- pmu-events/arch/nds32/mapfile.csv dependency dropped.
  make[3]: Circular pmu-events/arch/powerpc/mapfile.csv <- pmu-events/arch/powerpc/mapfile.csv dependency dropped.
  ...

Signed-off-by: James Clark 
Tested-by: Namhyung Kim 
Tested-by: Leo Yan 
Signed-off-by: Namhyung Kim

perf jevents: Remove unused makefile variable

2025-10-21T04:11:49+00:00

JDIR is unused since commit 4bb55de4ff03 ("perf jevents: Support copying
the source json files to OUTPUT"), remove it.

Signed-off-by: James Clark 
Tested-by: Leo Yan 
Signed-off-by: Namhyung Kim

perf jevents: Fix build when there are other json files in the tree

2025-10-21T04:11:49+00:00

The unquoted glob *.json will expand to a real file if, for example,
there is any file in the Perf source ending in .json. This can happen
when using tools like Bear and clangd which generate a
compile_commands.json file. With the glob already expanded by the shell,
the find command will fail to wildcard any real json events files.

Fix it by wrapping the star in quotes so it's passed to find rather than
the shell.

This fixes the following build error (most of the diff output omitted):

  $ make V=1 -C tools/perf O=/tmp/perf_build_with_json

  TEST    /tmp/perf_build_with_json/pmu-events/empty-pmu-events.log
  ...
   /* offset=121053 */ "node-access\000legacy cache\000Local memory read accesses\000legacy-cache-config=6\000\00010\000\000\000\000\000"
   /* offset=121135 */ "node-misses\000legacy cache\000Local memory read misses\000legacy-cache-config=0x10006\000\00010\000\000\000\000\000"
   /* offset=121221 */ "node-miss\000legacy cache\000Local memory read misses\000legacy-cache-config=0x10006\000\00010\000\000\000\000\000"
  ...
  -       {
                  .event_table = { 0, 0 },
                  .metric_table = { 0, 0 },
          },
  make[3]: *** [pmu-events/Build:54: /tmp/perf_build_with_json/pmu-events/empty-pmu-events.log] Error 1

Fixes: 4bb55de4ff03 ("perf jevents: Support copying the source json files to OUTPUT")
Signed-off-by: James Clark 
Reviewed-by: Leo Yan 
Tested-by: Leo Yan 
Signed-off-by: Namhyung Kim