On 2021/5/17 16:18, Peter Zijlstra wrote:
On Tue, May 11, 2021 at 10:42:03AM +0800, Like Xu wrote:The mask value of fixed counter control register should be dynamic adjusted with the number of fixed counters. This patch introduces a variable that includes the reserved bits of fixed counter control registers. This is needed for later Ice Lake fixed counter changes. Co-developed-by: Luwei Kang <luwei.kang@xxxxxxxxx> Signed-off-by: Luwei Kang <luwei.kang@xxxxxxxxx> Signed-off-by: Like Xu <like.xu@xxxxxxxxxxxxxxx> --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/vmx/pmu_intel.c | 6 +++++- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 55efbacfc244..49b421bd3dd8 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -457,6 +457,7 @@ struct kvm_pmu { unsigned nr_arch_fixed_counters; unsigned available_event_types; u64 fixed_ctr_ctrl; + u64 fixed_ctr_ctrl_mask; u64 global_ctrl; u64 global_status; u64 global_ovf_ctrl; diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c index d9dbebe03cae..ac7fe714e6c1 100644 --- a/arch/x86/kvm/vmx/pmu_intel.c +++ b/arch/x86/kvm/vmx/pmu_intel.c @@ -400,7 +400,7 @@ static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) case MSR_CORE_PERF_FIXED_CTR_CTRL: if (pmu->fixed_ctr_ctrl == data) return 0; - if (!(data & 0xfffffffffffff444ull)) { + if (!(data & pmu->fixed_ctr_ctrl_mask)) {Don't we already have hardware with more than 3 fixed counters?
Yes, so we update this mask based on the value of pmu->nr_arch_fixed_counters: + for (i = 0; i < pmu->nr_arch_fixed_counters; i++) + pmu->fixed_ctr_ctrl_mask &= ~(0xbull << (i * 4)); I assume this comment will not result in any code changes for this patch.
