Re: [PATCH 1/4] x86/perf/intel: Introduce PMU flag for Extended PEBS

[Peter Zijlstra]

On Mon, Jul 23, 2018 at 11:43:56AM -0400, Liang, Kan wrote:
> > So I like PEBS_ALL.. what I don't like is that it seems to be mutually
> > exclusive with PEBS Load Latency.
> 
> Right, MSR_PEBS_ENABLE:32-35 is model specific.

Doesn't mean they couldn't have avoided conflicting bits.

> For Atom,
>   Goldmont and earlier platform, they are reserved.
>   Goldmont Plus, 32-34 are for fixed counter, 35 is reserved.
> For Core,
>   from Nehalem to latest 8th, 32-35 are for Load Latency.

Seems rather unfortunate to me. Because PEBS_ALL is good, but since they
took conflicting bits, we'll have yet another variant when/if (I hope
they do) they bring it to Core :/