Re: [PATCH 0/1] Support PERF_SAMPLE_READ with inherit_stat

[Andi Kleen]

Ben Gainey <ben.gainey@xxxxxxx> writes:

> In this configuration stream ids (such as may appear in the read_format 
> field of a PERF_RECORD_SAMPLE) are no longer globally unique, rather 
> the pair of (stream id, tid) uniquely identify each event. Tools that 
> rely on this, for example to calculate a delta between samples, would 
> need updating to take this into account. Previously valid event 
> configurations (system-wide, no-inherit and so on) where each stream id 
> is the identifier are unaffected.

So is this an ABI break? It might need an optin, if it breaks anything,
which wouldn't surprise me. We do have a lot of different perf stream
parsers around these days and we cannot break them.

-Andi