From 1baa3f52c5c96e2e7116673bc167ae74413665d4 Mon Sep 17 00:00:00 2001 From: Yury Norov Date: Sun, 23 Jan 2022 10:38:37 -0800 Subject: [PATCH] KVM: x86: replace bitmap_weight with bitmap_empty where appropriate In some places kvm/hyperv.c code calls bitmap_weight() to check if any bit of a given bitmap is set. It's better to use bitmap_empty() in that case because bitmap_empty() stops traversing the bitmap as soon as it finds first set bit, while bitmap_weight() counts all bits unconditionally. Signed-off-by: Yury Norov Reviewed-by: Vitaly Kuznetsov Reviewed-by: Sean Christopherson Reviewed-by: Andy Shevchenko --- arch/x86/kvm/hyperv.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index 123b677111c58..c964923a7684d 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -90,7 +90,7 @@ static void synic_update_vector(struct kvm_vcpu_hv_synic *synic, { struct kvm_vcpu *vcpu = hv_synic_to_vcpu(synic); struct kvm_hv *hv = to_kvm_hv(vcpu->kvm); - int auto_eoi_old, auto_eoi_new; + bool auto_eoi_old, auto_eoi_new; if (vector < HV_SYNIC_FIRST_VALID_VECTOR) return; @@ -100,16 +100,16 @@ static void synic_update_vector(struct kvm_vcpu_hv_synic *synic, else __clear_bit(vector, synic->vec_bitmap); - auto_eoi_old = bitmap_weight(synic->auto_eoi_bitmap, 256); + auto_eoi_old = !bitmap_empty(synic->auto_eoi_bitmap, 256); if (synic_has_vector_auto_eoi(synic, vector)) __set_bit(vector, synic->auto_eoi_bitmap); else __clear_bit(vector, synic->auto_eoi_bitmap); - auto_eoi_new = bitmap_weight(synic->auto_eoi_bitmap, 256); + auto_eoi_new = !bitmap_empty(synic->auto_eoi_bitmap, 256); - if (!!auto_eoi_old == !!auto_eoi_new) + if (auto_eoi_old == auto_eoi_new) return; if (!enable_apicv) -- 2.39.5