2014-11-03 12:23-0600, Wei Huang: > > > On 11/03/2014 11:56 AM, Radim Krčmář wrote: > > 2014-10-31 12:05-0400, Wei Huang: > >> Currently KVM only supports vPMU for Intel platforms. This patch set > >> enable vPMU support for AMD platform by creating a common PMU > >> interface for x86. The PMU calls from guest VMs are dispatched > >> to corresponding functions defined in arch specific files. > > > > The functionality looks good, so I just want verify the basic design: > > why don't we emulate AMD PMU on Intel, and vice versa? > > (Underlying PERF_COUNTs are identical in both.) > > Thanks. The underlining perf counters can be very different between AMD > and Intel. I think we can emulate AMD on Intel, or vice versa, for some > common perfmon_events (such as PERF_COUNT_HW_CPU_CYCLES). But as soon as > guest VMs access raw counters (see PERF_TYPE_RAW), we can't emulate them > anymore. Thanks, I guess raw counters are used more than I thought, so code complexity would overshadow the gain of having at least something. And then, there is the always perfect, "who cares" :) -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
