[PATCH v1] perf stat: Don't print uncounted hwmon events

[PATCH v1] perf stat: Don't print uncounted hwmon events

[Ian Rogers]

Aggregation is different for core events compared to uncore. For
uncore we don't want the counts for events not in the aggregation
id. Switch the !counter->pmu->is_uncore test to a
counter->pmu->is_core as the hwmon PMU doesn't set the uncore
boolean. There are 2 booleans as some PMUs forget to set either
cpumask or cpus that are used to determine whether a PMU is uncore or
core. Also check config->aggr_get_id is present as the non-core
'software' PMU doesn't have it set.

Before:
```
$ perf stat --per-core -e temp_cpu -a true

 Performance counter stats for 'system wide':

S0-D0-C0              1              63.00 'C   temp_cpu
S0-D0-C1              0      <not counted> 'C   temp_cpu
S0-D0-C2              0      <not counted> 'C   temp_cpu
S0-D0-C3              0      <not counted> 'C   temp_cpu
S0-D0-C4              0      <not counted> 'C   temp_cpu
S0-D0-C5              0      <not counted> 'C   temp_cpu
S0-D0-C6              0      <not counted> 'C   temp_cpu
S0-D0-C7              0      <not counted> 'C   temp_cpu

       0.001375790 seconds time elapsed
```

After:
```
$ perf stat --per-core -e temp_cpu -a true

 Performance counter stats for 'system wide':

S0-D0-C0              1              38.00 'C   temp_cpu

       0.001260575 seconds time elapsed
```

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/util/stat-display.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/stat-display.c b/tools/perf/util/stat-display.c
index 91386429115d..ed3270ab2557 100644
--- a/tools/perf/util/stat-display.c
+++ b/tools/perf/util/stat-display.c
@@ -981,7 +981,7 @@ static bool should_skip_zero_counter(struct perf_stat_config *config,
 	 * Skip value 0 when it's an uncore event and the given aggr id
 	 * does not belong to the PMU cpumask.
 	 */
-	if (!counter->pmu || !counter->pmu->is_uncore)
+	if (!counter->pmu || counter->pmu->is_core || !config->aggr_get_id)
 		return false;
 
 	perf_cpu_map__for_each_cpu(cpu, idx, counter->pmu->cpus) {
-- 
2.49.0.472.ge94155a9ec-goog

Re: [PATCH v1] perf stat: Don't print uncounted hwmon events

[James Clark]

On 28/03/2025 4:53 am, Ian Rogers wrote:
> Aggregation is different for core events compared to uncore. For
> uncore we don't want the counts for events not in the aggregation
> id. Switch the !counter->pmu->is_uncore test to a
> counter->pmu->is_core as the hwmon PMU doesn't set the uncore
> boolean. There are 2 booleans as some PMUs forget to set either
> cpumask or cpus that are used to determine whether a PMU is uncore or
> core. Also check config->aggr_get_id is present as the non-core
> 'software' PMU doesn't have it set.
> 
> Before:
> ```
> $ perf stat --per-core -e temp_cpu -a true
> 
>   Performance counter stats for 'system wide':
> 
> S0-D0-C0              1              63.00 'C   temp_cpu
> S0-D0-C1              0      <not counted> 'C   temp_cpu
> S0-D0-C2              0      <not counted> 'C   temp_cpu
> S0-D0-C3              0      <not counted> 'C   temp_cpu
> S0-D0-C4              0      <not counted> 'C   temp_cpu
> S0-D0-C5              0      <not counted> 'C   temp_cpu
> S0-D0-C6              0      <not counted> 'C   temp_cpu
> S0-D0-C7              0      <not counted> 'C   temp_cpu
> 
>         0.001375790 seconds time elapsed
> ```
> 
> After:
> ```
> $ perf stat --per-core -e temp_cpu -a true
> 
>   Performance counter stats for 'system wide':
> 
> S0-D0-C0              1              38.00 'C   temp_cpu
> 
>         0.001260575 seconds time elapsed
> ```
> 
> Signed-off-by: Ian Rogers <irogers@google.com>
> ---
>   tools/perf/util/stat-display.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/perf/util/stat-display.c b/tools/perf/util/stat-display.c
> index 91386429115d..ed3270ab2557 100644
> --- a/tools/perf/util/stat-display.c
> +++ b/tools/perf/util/stat-display.c
> @@ -981,7 +981,7 @@ static bool should_skip_zero_counter(struct perf_stat_config *config,
>   	 * Skip value 0 when it's an uncore event and the given aggr id
>   	 * does not belong to the PMU cpumask.
>   	 */
> -	if (!counter->pmu || !counter->pmu->is_uncore)
> +	if (!counter->pmu || counter->pmu->is_core || !config->aggr_get_id)
>   		return false;
>   
>   	perf_cpu_map__for_each_cpu(cpu, idx, counter->pmu->cpus) {

Reviewed-by: James Clark <james.clark@linaro.org>