===================================================================
@@ -3659,6 +3659,7 @@
DEFINE_PROP_BOOL("lmce", X86CPU, enable_lmce, false),
DEFINE_PROP_BOOL("l3-cache", X86CPU, enable_l3_cache, true),
DEFINE_PROP_BOOL("vmware-cpuid-freq", X86CPU, vmware_cpuid_freq, true),
+ DEFINE_PROP_BOOL("allow-freq-hc", X86CPU, allow_freq_hc, false),
DEFINE_PROP_END_OF_LIST()
};
===================================================================
@@ -1243,6 +1243,12 @@
*/
bool enable_l3_cache;
+ /* Direct frequency hypercalls from guest userspace can be
+ * enabled/disabled via cpu option 'allow_freq_hc=on/off'.
+ * It is disabled by default.
+ */
+ bool allow_freq_hc;
+
/* Compatibility bits for old machine types: */
bool enable_cpuid_0xb;
===================================================================
@@ -163,6 +163,11 @@
has_x2apic_api);
}
+bool kvm_has_allow_freq_hc(void)
+{
+ return kvm_check_extension(kvm_state, KVM_CAP_ALLOW_FREQ_HC);
+}
+
static int kvm_get_tsc(CPUState *cs)
{
X86CPU *cpu = X86_CPU(cs);
@@ -692,6 +697,15 @@
return 0;
}
+static int kvm_set_vcpu_allow_freq(X86CPU *cpu)
+{
+ struct kvm_vcpu_allow_freq fr;
+
+ fr.enable = 1;
+
+ return kvm_vcpu_ioctl(CPU(cpu), KVM_SET_VCPU_ALLOW_FREQ_HC, &fr);
+}
+
static Error *invtsc_mig_blocker;
#define KVM_MAX_CPUID_ENTRIES 100
@@ -1040,6 +1054,21 @@
has_msr_tsc_aux = false;
}
+ if (cpu->allow_freq_hc) {
+ int ret;
+
+ if (!kvm_has_allow_freq_hc()) {
+ error_report("kvm: allow freq hypercall not supported");
+ return -ENOTSUP;
+ }
+
+ ret = kvm_set_vcpu_allow_freq(cpu);
+ if (ret) {
+ error_report("kvm: kvm_set_allow_freq failure, ret=%d", ret);
+ return ret;
+ }
+ }
+
return 0;
fail:
===================================================================
@@ -21,6 +21,7 @@
void kvm_synchronize_all_tsc(void);
void kvm_arch_reset_vcpu(X86CPU *cs);
void kvm_arch_do_init_vcpu(X86CPU *cs);
+bool kvm_has_allow_freq_hc(void);
int kvm_device_pci_assign(KVMState *s, PCIHostDeviceAddress *dev_addr,
uint32_t flags, uint32_t *dev_id);
Guests with DPDK, whose vcpus run isolated on physical CPUs, want to control the frequency of such physical CPUs. Introduce a allow-freq-hc CPU flag to enable such hypercalls. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> --- target/i386/cpu.c | 1 + target/i386/cpu.h | 6 ++++++ target/i386/kvm.c | 29 +++++++++++++++++++++++++++++ target/i386/kvm_i386.h | 1 + 4 files changed, 37 insertions(+)