On 29/04/20 10:54, Peter Zijlstra wrote: > On Wed, Apr 29, 2020 at 01:46:36PM +0800, Li RongQing wrote: >> Guest kernel reports a fixed cpu frequency in /proc/cpuinfo, >> this is confused to user when turbo is enable, and aperf/mperf >> can be used to show current cpu frequency after 7d5905dc14a >> "(x86 / CPU: Always show current CPU frequency in /proc/cpuinfo)" >> so we should emulate aperf mperf to achieve it >> >> the period of aperf/mperf in guest mode are accumulated as >> emulated value, and add per-VM knod to enable emulate mperfaperf >> >> diff v1: >> 1. support AMD >> 2. support per-vm capability to enable > Would it make sense to provide a pass-through APERF/MPERF for > KVM_HINTS_REALTIME ? Because that hint guarantees we have a 1:1 vCPU:CPU > binding and guaranteed no over-commit. >
Yes but that's up to userspace. Paolo
