On 12/9/21 04:52, Jim Mattson wrote:
Why don't we just use PERF_TYPE_RAW for guest counters all of the time? What is the advantage of matching entries in a table so that we can use PERF_TYPE_HARDWARE?
In theory it's so that hosts without support for architectural PMU events can map the architectural PMU events to their own. In practice, we can probably return early from intel_pmu_refresh if the host does not support X86_FEATURE_ARCH_PERFMON, because only the oldest Pentium 4 toasters^Wprocessors probably have VMX but lack architectural PMU.
Paolo
