kvm_pmu_cpuid_update makes a lot of bit manuiplation operations, when in fact there are already unions that can be used instead. Changing the bit manipulation to the union for clarity. This patch does not change the functionality. Signed-off-by: Nadav Amit <namit@xxxxxxxxxxxxxxxxx> --- arch/x86/kvm/pmu.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c index 3dd6acc..8e6b7d8 100644 --- a/arch/x86/kvm/pmu.c +++ b/arch/x86/kvm/pmu.c @@ -15,6 +15,7 @@ #include <linux/types.h> #include <linux/kvm_host.h> #include <linux/perf_event.h> +#include <asm/perf_event.h> #include "x86.h" #include "cpuid.h" #include "lapic.h" @@ -463,7 +464,8 @@ void kvm_pmu_cpuid_update(struct kvm_vcpu *vcpu) { struct kvm_pmu *pmu = &vcpu->arch.pmu; struct kvm_cpuid_entry2 *entry; - unsigned bitmap_len; + union cpuid10_eax eax; + union cpuid10_edx edx; pmu->nr_arch_gp_counters = 0; pmu->nr_arch_fixed_counters = 0; @@ -475,25 +477,27 @@ void kvm_pmu_cpuid_update(struct kvm_vcpu *vcpu) entry = kvm_find_cpuid_entry(vcpu, 0xa, 0); if (!entry) return; + eax.full = entry->eax; + edx.full = entry->edx; - pmu->version = entry->eax & 0xff; + pmu->version = eax.split.version_id; if (!pmu->version) return; - pmu->nr_arch_gp_counters = min((int)(entry->eax >> 8) & 0xff, - INTEL_PMC_MAX_GENERIC); - pmu->counter_bitmask[KVM_PMC_GP] = - ((u64)1 << ((entry->eax >> 16) & 0xff)) - 1; - bitmap_len = (entry->eax >> 24) & 0xff; - pmu->available_event_types = ~entry->ebx & ((1ull << bitmap_len) - 1); + pmu->nr_arch_gp_counters = min_t(int, eax.split.num_counters, + INTEL_PMC_MAX_GENERIC); + pmu->counter_bitmask[KVM_PMC_GP] = ((u64)1 << eax.split.bit_width) - 1; + pmu->available_event_types = ~entry->ebx & + ((1ull << eax.split.mask_length) - 1); if (pmu->version == 1) { pmu->nr_arch_fixed_counters = 0; } else { - pmu->nr_arch_fixed_counters = min((int)(entry->edx & 0x1f), + pmu->nr_arch_fixed_counters = + min_t(int, edx.split.num_counters_fixed, INTEL_PMC_MAX_FIXED); pmu->counter_bitmask[KVM_PMC_FIXED] = - ((u64)1 << ((entry->edx >> 5) & 0xff)) - 1; + ((u64)1 << edx.split.bit_width_fixed) - 1; } pmu->global_ctrl = ((1 << pmu->nr_arch_gp_counters) - 1) | -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html