Re: [PATCH v4 5/6] KVM: x86/vPMU: Reuse perf_event to avoid unnecessary pmc_reprogram_counter

[Wanpeng Li]

On Mon, 28 Oct 2019 at 21:06, Like Xu <like.xu@xxxxxxxxxxxxxxx> wrote:
>
> The perf_event_create_kernel_counter() in the pmc_reprogram_counter() is
> a heavyweight and high-frequency operation, especially when host disables
> the watchdog (maximum 21000000 ns) which leads to an unacceptable latency

Why when host disables the watchdog,
perf_event_create_kernel_counter() is more heavyweight and
high-frequency operation?

    Wanpeng