On Mon, Mar 24, 2025 at 05:31:14PM +0000, Mingwei Zhang wrote: > From: Sandipan Das <sandipan.das@xxxxxxx> > > Apply the PERF_PMU_CAP_MEDIATED_VPMU flag for version 2 and later > implementations of the core PMU. Aside from having Global Control and > Status registers, virtualizing the PMU using the passthrough model > requires an interface to set or clear the overflow bits in the Global > Status MSRs while restoring or saving the PMU context of a vCPU. > > PerfMonV2-capable hardware has additional MSRs for this purpose namely, > PerfCntrGlobalStatusSet and PerfCntrGlobalStatusClr, thereby making it > suitable for use with mediated vPMU. So IBS cannot be used in the guest (with MEDIATED_VPMU) and host can profile guests with it, right? Thanks, Namhyung > > Signed-off-by: Sandipan Das <sandipan.das@xxxxxxx> > Signed-off-by: Mingwei Zhang <mizhang@xxxxxxxxxx> > --- > arch/x86/events/amd/core.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c > index 30d6ceb4c8ad..a8b537dd2ddb 100644 > --- a/arch/x86/events/amd/core.c > +++ b/arch/x86/events/amd/core.c > @@ -1433,6 +1433,8 @@ static int __init amd_core_pmu_init(void) > > amd_pmu_global_cntr_mask = x86_pmu.cntr_mask64; > > + x86_get_pmu(smp_processor_id())->capabilities |= PERF_PMU_CAP_MEDIATED_VPMU; > + > /* Update PMC handling functions */ > x86_pmu.enable_all = amd_pmu_v2_enable_all; > x86_pmu.disable_all = amd_pmu_v2_disable_all; > -- > 2.49.0.395.g12beb8f557-goog >
