Re: [PATCH v5 07/12] perf/x86: no counter allocation support

[Andi Kleen]

> diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
> index 9de8780..ec97a70 100644
> --- a/include/uapi/linux/perf_event.h
> +++ b/include/uapi/linux/perf_event.h
> @@ -372,7 +372,8 @@ struct perf_event_attr {
>  				context_switch :  1, /* context switch data */
>  				write_backward :  1, /* Write ring buffer from end to beginning */
>  				namespaces     :  1, /* include namespaces data */
> -				__reserved_1   : 35;
> +				no_counter     :  1, /* no counter allocation */

Not sure we really want to expose this in the user ABI. Perhaps make
it a feature of the in kernel API only?

-Andi