KVM: x86 emulator: add get_cached_segment_base() callback to x86_emulate_ops

On VMX it is expensive to call get_cached_descriptor() just to get segment
base since multiple vmcs_reads are done instead of only one. Introduce
new call back get_cached_segment_base() for efficiency.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Gleb Natapov
2010-04-28 19:15:29 +03:00
committed by Avi Kivity
parent 3fb1b5dbd3
commit 5951c44237
3 changed files with 9 additions and 12 deletions

View File

@ -3714,6 +3714,12 @@ static void emulator_get_gdt(struct desc_ptr *dt, struct kvm_vcpu *vcpu)
kvm_x86_ops->get_gdt(vcpu, dt);
}
static unsigned long emulator_get_cached_segment_base(int seg,
struct kvm_vcpu *vcpu)
{
return get_segment_base(vcpu, seg);
}
static bool emulator_get_cached_descriptor(struct desc_struct *desc, int seg,
struct kvm_vcpu *vcpu)
{
@ -3804,6 +3810,7 @@ static struct x86_emulate_ops emulate_ops = {
.set_cached_descriptor = emulator_set_cached_descriptor,
.get_segment_selector = emulator_get_segment_selector,
.set_segment_selector = emulator_set_segment_selector,
.get_cached_segment_base = emulator_get_cached_segment_base,
.get_gdt = emulator_get_gdt,
.get_cr = emulator_get_cr,
.set_cr = emulator_set_cr,