On Thu, Aug 14, 2025 at 2:26 AM James Clark <james.clark@linaro.org> wrote:
>
> Arm FEAT_SPE_FDS adds the ability to filter on the data source of a
> packet using another 64-bits of event filtering control. As the existing
> perf_event_attr::configN fields are all used up for SPE PMU, an
> additional field is needed. Add a new 'config4' field.
Somewhat off-topic, imo it would be nice if we could land:
https://lore.kernel.org/lkml/20250603181634.1362626-1-ctshao@google.com/
and show all the config values via fdinfo to better allow tools to
diagnose when PMUs are busy, etc. The patch there tries to be minimal
and just reveal config (even with being minimal the patch is stalled).
Thanks,
Ian
> Reviewed-by: Leo Yan <leo.yan@arm.com>
> Tested-by: Leo Yan <leo.yan@arm.com>
> Reviewed-by: Ian Rogers <irogers@google.com>
> Signed-off-by: James Clark <james.clark@linaro.org>
> ---
> include/uapi/linux/perf_event.h | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
> index 78a362b80027..0d0ed85ad8cb 100644
> --- a/include/uapi/linux/perf_event.h
> +++ b/include/uapi/linux/perf_event.h
> @@ -382,6 +382,7 @@ enum perf_event_read_format {
> #define PERF_ATTR_SIZE_VER6 120 /* Add: aux_sample_size */
> #define PERF_ATTR_SIZE_VER7 128 /* Add: sig_data */
> #define PERF_ATTR_SIZE_VER8 136 /* Add: config3 */
> +#define PERF_ATTR_SIZE_VER9 144 /* add: config4 */
>
> /*
> * 'struct perf_event_attr' contains various attributes that define
> @@ -543,6 +544,7 @@ struct perf_event_attr {
> __u64 sig_data;
>
> __u64 config3; /* extension of config2 */
> + __u64 config4; /* extension of config3 */
> };
>
> /*
>
> --
> 2.34.1
>