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68cb156743
evsel__count_has_error() fails counters when the enabled or running time
are 0. The duration_time event reads 0 when the cpu_map_idx != 0 to
avoid aggregating time over CPUs. Change the enable and running time
to always have a ratio of 100% so that evsel__count_has_error won't
fail.
Before:
```
$ sudo /tmp/perf/perf stat --per-core -a -M UNCORE_FREQ sleep 1
Performance counter stats for 'system wide':
S0-D0-C0 1 2,615,819,485 UNC_CLOCK.SOCKET # 2.61 UNCORE_FREQ
S0-D0-C0 2 <not counted> duration_time
1.002111784 seconds time elapsed
```
After:
```
$ perf stat --per-core -a -M UNCORE_FREQ sleep 1
Performance counter stats for 'system wide':
S0-D0-C0 1 758,160,296 UNC_CLOCK.SOCKET # 0.76 UNCORE_FREQ
S0-D0-C0 2 1,003,438,246 duration_time
1.002486017 seconds time elapsed
```
Note: the metric reads the value a different way and isn't impacted.
Fixes: 240505b2d0 ("perf tool_pmu: Factor tool events into their own PMU")
Reported-by: Stephane Eranian <eranian@google.com>
Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Link: https://lore.kernel.org/r/20250423050358.94310-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.