Re: [REGRESSION][BISECT] perf/core: Remove pmu linear searching code

[Peter Zijlstra]

On Mon, Jun 05, 2023 at 11:27:31AM +0200, Peter Zijlstra wrote:
> On Mon, Jun 05, 2023 at 08:10:15AM +0100, Mark Rutland wrote:
> 
> > How does this work on x86? Do you have pseudo-PMUs for PERF_TYPE_HARDWARE and
> > PERF_TYPE_RAW ?
> 
> Generic code maps TYPE_HARDWARE and TYPE_HW_CACHE to TYPE_RAW for a
> first go, only if that fails it will try the actual type.
> 
> And x86 has the (first) CPU PMU has TYPE_RAW, on hybrid, it will
> transparently pick the right actual PMU.

Oh, I might've misread that last bit.. TYPE_RAW is always the big core,
it will not magic the thing. If you want little events you gotta
manually find the little pmu.