Re: [PATCH] KVM: x86/vPMU: Declare kvm_pmu->reprogram_pmi field using DECLARE_BITMAP

From: Paolo Bonzini
Date: Tue Oct 22 2019 - 07:40:15 EST


On 21/10/19 12:55, Like Xu wrote:
> Replace the explicit declaration of "u64 reprogram_pmi" with the generic
> macro DECLARE_BITMAP for all possible appropriate number of bits.
>
> Suggested-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> Signed-off-by: Like Xu <like.xu@xxxxxxxxxxxxxxx>
> ---
> arch/x86/include/asm/kvm_host.h | 2 +-
> arch/x86/kvm/pmu.c | 15 +++++----------
> 2 files changed, 6 insertions(+), 11 deletions(-)
>
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index 50eb430b0ad8..236a876a5a2e 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -469,7 +469,7 @@ struct kvm_pmu {
> struct kvm_pmc gp_counters[INTEL_PMC_MAX_GENERIC];
> struct kvm_pmc fixed_counters[INTEL_PMC_MAX_FIXED];
> struct irq_work irq_work;
> - u64 reprogram_pmi;
> + DECLARE_BITMAP(reprogram_pmi, X86_PMC_IDX_MAX);
> };
>
> struct kvm_pmu_ops;
> diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
> index 46875bbd0419..75e8f9fae031 100644
> --- a/arch/x86/kvm/pmu.c
> +++ b/arch/x86/kvm/pmu.c
> @@ -62,8 +62,7 @@ static void kvm_perf_overflow(struct perf_event *perf_event,
> struct kvm_pmc *pmc = perf_event->overflow_handler_context;
> struct kvm_pmu *pmu = pmc_to_pmu(pmc);
>
> - if (!test_and_set_bit(pmc->idx,
> - (unsigned long *)&pmu->reprogram_pmi)) {
> + if (!test_and_set_bit(pmc->idx, pmu->reprogram_pmi)) {
> __set_bit(pmc->idx, (unsigned long *)&pmu->global_status);
> kvm_make_request(KVM_REQ_PMU, pmc->vcpu);
> }
> @@ -76,8 +75,7 @@ static void kvm_perf_overflow_intr(struct perf_event *perf_event,
> struct kvm_pmc *pmc = perf_event->overflow_handler_context;
> struct kvm_pmu *pmu = pmc_to_pmu(pmc);
>
> - if (!test_and_set_bit(pmc->idx,
> - (unsigned long *)&pmu->reprogram_pmi)) {
> + if (!test_and_set_bit(pmc->idx, pmu->reprogram_pmi)) {
> __set_bit(pmc->idx, (unsigned long *)&pmu->global_status);
> kvm_make_request(KVM_REQ_PMU, pmc->vcpu);
>
> @@ -137,7 +135,7 @@ static void pmc_reprogram_counter(struct kvm_pmc *pmc, u32 type,
> }
>
> pmc->perf_event = event;
> - clear_bit(pmc->idx, (unsigned long*)&pmc_to_pmu(pmc)->reprogram_pmi);
> + clear_bit(pmc->idx, pmc_to_pmu(pmc)->reprogram_pmi);
> }
>
> void reprogram_gp_counter(struct kvm_pmc *pmc, u64 eventsel)
> @@ -253,16 +251,13 @@ EXPORT_SYMBOL_GPL(reprogram_counter);
> void kvm_pmu_handle_event(struct kvm_vcpu *vcpu)
> {
> struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
> - u64 bitmask;
> int bit;
>
> - bitmask = pmu->reprogram_pmi;
> -
> - for_each_set_bit(bit, (unsigned long *)&bitmask, X86_PMC_IDX_MAX) {
> + for_each_set_bit(bit, pmu->reprogram_pmi, X86_PMC_IDX_MAX) {
> struct kvm_pmc *pmc = kvm_x86_ops->pmu_ops->pmc_idx_to_pmc(pmu, bit);
>
> if (unlikely(!pmc || !pmc->perf_event)) {
> - clear_bit(bit, (unsigned long *)&pmu->reprogram_pmi);
> + clear_bit(bit, pmu->reprogram_pmi);
> continue;
> }
>
>

Queued, thanks.

Paolo