KVM: Convert kvm_for_each_vcpu() to using xa_for_each_range()

Now that the vcpu array is backed by an xarray, use the optimised
iterator that matches the underlying data structure.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Message-Id: <20211116160403.4074052-8-maz@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 7da6086..6654828 100644 (file)
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -705,11 +705,9 @@ static inline struct kvm_vcpu *kvm_get_vcpu(struct kvm *kvm, int i)
        return xa_load(&kvm->vcpu_array, i);
 }
 
-#define kvm_for_each_vcpu(idx, vcpup, kvm) \
-       for (idx = 0; \
-            idx < atomic_read(&kvm->online_vcpus) && \
-            (vcpup = kvm_get_vcpu(kvm, idx)) != NULL; \
-            idx++)
+#define kvm_for_each_vcpu(idx, vcpup, kvm)                \
+       xa_for_each_range(&kvm->vcpu_array, idx, vcpup, 0, \
+                         (atomic_read(&kvm->online_vcpus) - 1))
 
 static inline struct kvm_vcpu *kvm_get_vcpu_by_id(struct kvm *kvm, int id)
 {