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

From: Peter Zijlstra
Date: Mon Jun 05 2023 - 05:28:04 EST


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.

That said; given that this commit has been tagged twice now, I suppose I
should go revert it and we'll try again after a more thorough audit.