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

[Liang, Kan]

On 7/23/2018 11:16 AM, Peter Zijlstra wrote:
> On Thu, Mar 08, 2018 at 06:15:39PM -0800, kan.liang@xxxxxxxxxxxxxxx wrote:
> > From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
> >
> > The Extended PEBS feature, introduced in Goldmont Plus
> > microarchitecture, supports all events as "Extended PEBS".
> >
> > Introduce flag PMU_FL_PEBS_ALL to indicate the platforms which support
> > extended PEBS.
> > To support all events, it needs to support all constraints for PEBS. To
> > avoid duplicating all the constraints in the PEBS table, making the PEBS
> > code search the normal constraints too.
>
> 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.
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.

> Took the patches.
Thanks.

Kan