diff options
| author | Radim Krčmář <rkrcmar@redhat.com> | 2016-10-10 17:28:48 +0200 |
|---|---|---|
| committer | Eduardo Habkost <ehabkost@redhat.com> | 2016-10-17 15:44:49 -0200 |
| commit | 2a138ec3af871cd42a982eb401f16dcb74cba8d3 (patch) | |
| tree | c861b9f9dc822383ba6571df94f2a4d097eed6a6 /target-i386 | |
| parent | fb506e701e9bafa3e0685747c1c98962c52d1962 (diff) | |
target-i386/kvm: cache the return value of kvm_enable_x2apic()
Assume that KVM would have returned the same on subsequent runs.
Abstract the memoizaiton pattern into macros and call it memorize as
adding the r makes it less obscure.
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Diffstat (limited to 'target-i386')
| -rw-r--r-- | target-i386/kvm.c | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/target-i386/kvm.c b/target-i386/kvm.c index 0fd6646486..0472f45fd0 100644 --- a/target-i386/kvm.c +++ b/target-i386/kvm.c @@ -129,10 +129,23 @@ static bool kvm_x2apic_api_set_flags(uint64_t flags) return !kvm_vm_enable_cap(s, KVM_CAP_X2APIC_API, 0, flags); } +#define MEMORIZE(fn) \ + ({ \ + static typeof(fn) _result; \ + static bool _memorized; \ + \ + if (_memorized) { \ + return _result; \ + } \ + _memorized = true; \ + _result = fn; \ + }) + bool kvm_enable_x2apic(void) { - return kvm_x2apic_api_set_flags(KVM_X2APIC_API_USE_32BIT_IDS | - KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK); + return MEMORIZE( + kvm_x2apic_api_set_flags(KVM_X2APIC_API_USE_32BIT_IDS | + KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK)); } static int kvm_get_tsc(CPUState *cs) |