On Friday, February 15, 2019 12:26 AM, Andi Kleen wrote: > > 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? OK. I plan to move it to the perf_event struct. Best, Wei