[PATCH] powerpc/perf/hv-24x7: Dont create sysfs event files for dummy events

Madhavan Srinivasan maddy at linux.ibm.com
Thu Dec 17 22:40:43 AEDT 2020


On 12/17/20 5:02 PM, Kajol Jain wrote:
> hv_24x7 performance monitoring unit creates list of supported events
> from the event catalog obtained via HCALL. hv_24x7 catalog could also
> contain invalid or dummy events (with names like FREE_  or CPM_FREE_ so


Can you also include " RESERVED_NEST*" as part of the check.

# ls /sys/devices/hv_24x7/events | grep RESERVED
RESERVED_NEST1
RESERVED_NEST10
RESERVED_NEST11
RESERVED_NEST12
...


Maddy


> on). These events does not have any hardware counters backing them.
> So patch adds a check to string compare the event names to filter
> out them.
>
> Signed-off-by: Kajol Jain <kjain at linux.ibm.com>
> ---
>   arch/powerpc/perf/hv-24x7.c | 8 ++++++++
>   1 file changed, 8 insertions(+)
>
> diff --git a/arch/powerpc/perf/hv-24x7.c b/arch/powerpc/perf/hv-24x7.c
> index 6e7e820508df..c3252d8a7818 100644
> --- a/arch/powerpc/perf/hv-24x7.c
> +++ b/arch/powerpc/perf/hv-24x7.c
> @@ -894,6 +894,11 @@ static int create_events_from_catalog(struct attribute ***events_,
>
>   		name = event_name(event, &nl);
>
> +		if (strstr(name, "FREE_")) {
> +			pr_info("invalid event %zu (%.*s)\n", event_idx, nl, name);
> +			junk_events++;
> +			continue;
> +		}
>   		if (event->event_group_record_len == 0) {
>   			pr_devel("invalid event %zu (%.*s): group_record_len == 0, skipping\n",
>   					event_idx, nl, name);
> @@ -955,6 +960,9 @@ static int create_events_from_catalog(struct attribute ***events_,
>   			continue;
>
>   		name  = event_name(event, &nl);
> +		if (strstr(name, "FREE_"))
> +			continue;
> +
>   		nonce = event_uniq_add(&ev_uniq, name, nl, event->domain);
>   		ct    = event_data_to_attrs(event_idx, events + event_attr_ct,
>   					    event, nonce);


More information about the Linuxppc-dev mailing list