If no user-specified TSC rate is present, we will try to set
env->tsc_khz to the value returned by KVM_GET_TSC_KHZ. This patch
does not change the current functionality of QEMU and just
prepares for later patches to enable migrating vcpu's TSC rate.
Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
}
}
+ /* vcpu's TSC frequency is either specified by user, or following
+ * the value used by KVM if the former is not present. In the
+ * latter case, we query it from KVM and record in env->tsc_khz,
+ * so that vcpu's TSC frequency can be migrated later via this field.
+ */
+ if (!env->tsc_khz) {
+ r = kvm_check_extension(cs->kvm_state, KVM_CAP_GET_TSC_KHZ) ?
+ kvm_vcpu_ioctl(cs, KVM_GET_TSC_KHZ) :
+ -ENOTSUP;
+ if (r > 0) {
+ env->tsc_khz = r;
+ }
+ }
+
if (has_xsave) {
env->kvm_xsave_buf = qemu_memalign(4096, sizeof(struct kvm_xsave));
}