Re: [PATCH 16/16] perf tools: Add support for SPF events

[Anshuman Khandual <khandual@linux.vnet.ibm.com>]

On 08/08/2017 08:05 PM, Laurent Dufour wrote:
> Add support for the new speculative faults events.
> 
> Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
> ---
>  tools/include/uapi/linux/perf_event.h | 2 ++
>  tools/perf/util/evsel.c               | 2 ++
>  tools/perf/util/parse-events.c        | 8 ++++++++
>  tools/perf/util/parse-events.l        | 2 ++
>  tools/perf/util/python.c              | 2 ++
>  5 files changed, 16 insertions(+)
> 
> diff --git a/tools/include/uapi/linux/perf_event.h b/tools/include/uapi/linux/perf_event.h
> index b1c0b187acfe..fbfb03dff334 100644
> --- a/tools/include/uapi/linux/perf_event.h
> +++ b/tools/include/uapi/linux/perf_event.h
> @@ -111,6 +111,8 @@ enum perf_sw_ids {
>  	PERF_COUNT_SW_EMULATION_FAULTS		= 8,
>  	PERF_COUNT_SW_DUMMY			= 9,
>  	PERF_COUNT_SW_BPF_OUTPUT		= 10,
> +	PERF_COUNT_SW_SPF_DONE			= 11,
> +	PERF_COUNT_SW_SPF_FAILED		= 12,
>  

PERF_COUNT_SW_SPF_FAULTS makes sense but not the FAILED one. IIRC,
there are no error path counting in perf SW events at the moment.
SPF_FAULTS and SPF_FAILS are VM internal events like THP collapse
etc. IMHO it should be added as a VM statistics counter or as a
trace point event instead.