Re: [PATCH v6 6/8] KVM: x86/pmu: Move RDPMC emulation into per-vendor callbacks

[Jim Mattson]

On Mon, Jun 29, 2026 at 4:28 PM Zide Chen <zide.chen@xxxxxxxxx> wrote:
>
> The current RDPMC emulation splits responsibility: rdpmc_ecx_to_pmc()
> in each vendor returns a kvm_pmc, then common code calls
> pmc_read_counter().
>
> This design cannot support RDPMC reads that don't map to a counter,
> such as PERF_METRICS on Intel platforms.
>
> Replace rdpmc_ecx_to_pmc() with emulate_rdpmc(), which takes full
> ownership of the emulation and writes the result directly into @data.
>
> Also drop the redundant bitmask in intel_emulate_rdpmc() since
> pmc_read_counter() already applies the counter's bit-width mask.
>
> No functional change intended.
>
> Signed-off-by: Zide Chen <zide.chen@xxxxxxxxx>
Reviewed-by: Jim Mattson <jmattson@xxxxxxxxxx>