Re: [PATCH] perf/core: Emit PERF_RECORD_LOST for pinned events

[Andi Kleen]

> > I don't think I object to having an even in the stream, but your LOST
> > event is unfortunate in that it itself can get lost when there's no
> > space in the buffer (which arguably is unlikely, but still).
> >
> > So from that point of view, I think overloading LOST is not so very nice
> > for this.
> 
> But anything can get lost in case of no space.
> Do you want to use something other than the LOST event?

Could always reserve the last entry in the ring buffer for a LOST event,
that would guarantee you can always get one out.

-Andi