Commit Graph

10 Commits

Author SHA1 Message Date
Ian Rogers
bc105a8918 Revert "perf tool_pmu: More accurately set the cpus for tool events"
This reverts commit d8d8a0b360.

The setting of a user CPU map can cause an empty intersection when
combined with CPU 0 and the event removed. This later triggers a segv in
the stat-shadow logic. Let's put back a full online CPU map for now by
reverting this patch.

Closes: https://lore.kernel.org/linux-perf-users/cgja46br2smmznxs7kbeabs6zgv3b4olfqgh2fdp5mxk2yom4v@w6jjgov6hdi6/
Reported-by: Andres Freund <andres@anarazel.de>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dapeng Mi <dapeng1.mi@linux.intel.com>
Cc: Dr. David Alan Gilbert <linux@treblig.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Falcon <thomas.falcon@intel.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-02-10 09:32:34 -03:00
Ian Rogers
d8d8a0b360 perf tool_pmu: More accurately set the cpus for tool events
The user and system time events can record on different CPUs, but for
all other events a single CPU map of just CPU 0 makes sense. In
parse-events detect a tool PMU and then pass the perf_event_attr so
that the tool_pmu can return CPUs specific for the event. This avoids
a CPU map of all online CPUs being used for events like
duration_time. Avoiding this avoids the evlist CPUs containing CPUs
for which duration_time just gives 0. Minimizing the evlist CPUs can
remove unnecessary sched_setaffinity syscalls that delay metric
calculations.

Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-11-17 18:43:09 -08:00
Ian Rogers
68cc6ec3ac perf tool_pmu: Make core_wide and target_cpu json events
For the sake of better documentation, add core_wide and target_cpu to
the tool.json. When the values of system_wide and
user_requested_cpu_list are unknown, use the values from the global
stat_config.

Example output showing how '-a' modifies the values in `perf stat`:
```
$ perf stat -e core_wide,target_cpu true

 Performance counter stats for 'true':

                 0      core_wide
                 0      target_cpu

       0.000993787 seconds time elapsed

       0.001128000 seconds user
       0.000000000 seconds sys

$ perf stat -e core_wide,target_cpu -a true

 Performance counter stats for 'system wide':

                 1      core_wide
                 1      target_cpu

       0.002271723 seconds time elapsed

$ perf list
...
tool:
  core_wide
       [1 if not SMT,if SMT are events being gathered on all SMT threads 1 otherwise 0. Unit: tool]
...
  target_cpu
       [1 if CPUs being analyzed,0 if threads/processes. Unit: tool]
...
```

Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-11-11 16:48:36 -08:00
Ian Rogers
175c852325 perf tool_pmu: Allow num_cpus(_online) to be specific to a cpumask
For hybrid metrics it is useful to know the number of p-core or e-core
CPUs. If a cpumask is specified for the num_cpus or num_cpus_online
tool events, compute the value relative to the given mask rather than
for the full system.

```
$ sudo /tmp/perf/perf stat -e 'tool/num_cpus/,tool/num_cpus,cpu=cpu_core/,
  tool/num_cpus,cpu=cpu_atom/,tool/num_cpus_online/,tool/num_cpus_online,
  cpu=cpu_core/,tool/num_cpus_online,cpu=cpu_atom/' true

 Performance counter stats for 'true':

                28      tool/num_cpus/
                16      tool/num_cpus,cpu=cpu_core/
                12      tool/num_cpus,cpu=cpu_atom/
                28      tool/num_cpus_online/
                16      tool/num_cpus_online,cpu=cpu_core/
                12      tool/num_cpus_online,cpu=cpu_atom/

       0.000767205 seconds time elapsed

       0.000938000 seconds user
       0.000000000 seconds sys
```

Reviewed-by: Thomas Falcon <thomas.falcon@intel.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: James Clark <james.clark@linaro.org>
Link: https://lore.kernel.org/r/20250719030517.1990983-6-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-07-24 13:41:35 -07:00
James Clark
72c6f57a41 perf pmu: Dynamically allocate tool PMU
perf_pmus__destroy() treats all PMUs as allocated and free's them so we
can't have any static PMUs that are added to the PMU lists. Fix it by
allocating the tool PMU in the same way as the others. Current users of
the tool PMU already use find_pmu() and not perf_pmus__tool_pmu(), so
rename the function to add 'new' to avoid it being misused in the
future.

perf_pmus__fake_pmu() can remain as static as it's not added to the
PMU lists.

Fixes the following error:

  $ perf bench internals pmu-scan

  # Running 'internals/pmu-scan' benchmark:
  Computing performance of sysfs PMU event scan for 100 times
  munmap_chunk(): invalid pointer
  Aborted (core dumped)

Fixes: 240505b2d0 ("perf tool_pmu: Factor tool events into their own PMU")
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Link: https://lore.kernel.org/r/20250226104111.564443-2-james.clark@linaro.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-02-26 16:23:47 -08:00
Ian Rogers
609aa2667f perf tool_pmu: Switch to standard pmu functions and json descriptions
Use the regular PMU approaches with tool json events to reduce the
amount of special tool_pmu code - tool_pmu__config_terms and
tool_pmu__for_each_event_cb are removed. Some functions remain, like
tool_pmu__str_to_event, as conveniences to metricgroups. Add
tool_pmu__skip_event/tool_pmu__num_skip_events to handle the case that
tool json events shouldn't appear on certain architectures. This isn't
done in jevents.py due to complexity in the empty-pmu-events.c and
when all vendor json is built into the tool.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20241002032016.333748-10-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2024-10-10 23:40:33 -07:00
Ian Rogers
069057239a perf tool_pmu: Move expr literals to tool_pmu
Add the expr literals like "#smt_on" as tool events, this allows stat
events to give the values. On my laptop with hyperthreading enabled:

```
$ perf stat -e "has_pmem,num_cores,num_cpus,num_cpus_online,num_dies,num_packages,smt_on,system_tsc_freq" true

 Performance counter stats for 'true':

                 0      has_pmem
                 8      num_cores
                16      num_cpus
                16      num_cpus_online
                 1      num_dies
                 1      num_packages
                 1      smt_on
     2,496,000,000      system_tsc_freq

       0.001113637 seconds time elapsed

       0.001218000 seconds user
       0.000000000 seconds sys
```

And with hyperthreading disabled:
```
$ perf stat -e "has_pmem,num_cores,num_cpus,num_cpus_online,num_dies,num_packages,smt_on,system_tsc_freq" true

 Performance counter stats for 'true':

                 0      has_pmem
                 8      num_cores
                16      num_cpus
                 8      num_cpus_online
                 1      num_dies
                 1      num_packages
                 0      smt_on
     2,496,000,000      system_tsc_freq

       0.000802115 seconds time elapsed

       0.000000000 seconds user
       0.000806000 seconds sys
```

As zero matters for these values, in stat-display
should_skip_zero_counter only skip the zero value if it is not the
first aggregation index.

The tool event implementations are used in expr but not evaluated as
events for simplicity. Also core_wide isn't made a tool event as it
requires command line parameters.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20241002032016.333748-8-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2024-10-10 23:40:32 -07:00
Ian Rogers
b8f1a1b068 perf tool_pmu: Rename perf_tool_event__* to tool_pmu__*
Now the events are associated with the tool PMU, rename the functions
to reflect this.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20241002032016.333748-7-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2024-10-10 23:40:32 -07:00
Ian Rogers
0709a82c10 perf tool_pmu: Rename enum perf_tool_event to tool_pmu_event
To better reflect the events listed are from the tool PMU. Rename the
enum values from PERF_TOOL_* to TOOL_PMU__EVENT_*.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20241002032016.333748-6-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2024-10-10 23:40:32 -07:00
Ian Rogers
240505b2d0 perf tool_pmu: Factor tool events into their own PMU
Rather than treat tool events as a special kind of event, create a
tool only PMU where the events/aliases match the existing
duration_time, user_time and system_time events. Remove special
parsing and printing support for the tool events, but add function
calls for when PMU functions are called on a tool_pmu.

Move the tool PMU code in evsel into tool_pmu.c to better encapsulate
the tool event behavior in that file.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20241002032016.333748-5-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2024-10-10 23:40:32 -07:00