[PATCH 32/46] KVM: Replace kvmclock open-coded get_cpu_var() with the real thing

From: Avi Kivity
Date: Wed May 20 2009 - 07:21:43 EST


Suggested by Ingo Molnar.

Signed-off-by: Avi Kivity <avi@xxxxxxxxxx>
---
arch/x86/kvm/x86.c | 11 ++++++-----
1 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 0c45df9..a7ea26e 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -627,16 +627,17 @@ static void kvm_write_guest_time(struct kvm_vcpu *v)
unsigned long flags;
struct kvm_vcpu_arch *vcpu = &v->arch;
void *shared_kaddr;
+ unsigned long this_tsc_khz;

if ((!vcpu->time_page))
return;

- preempt_disable();
- if (unlikely(vcpu->hv_clock_tsc_khz != __get_cpu_var(cpu_tsc_khz))) {
- kvm_set_time_scale(__get_cpu_var(cpu_tsc_khz), &vcpu->hv_clock);
- vcpu->hv_clock_tsc_khz = __get_cpu_var(cpu_tsc_khz);
+ this_tsc_khz = get_cpu_var(cpu_tsc_khz);
+ if (unlikely(vcpu->hv_clock_tsc_khz != this_tsc_khz)) {
+ kvm_set_time_scale(this_tsc_khz, &vcpu->hv_clock);
+ vcpu->hv_clock_tsc_khz = this_tsc_khz;
}
- preempt_enable();
+ put_cpu_var(cpu_tsc_khz);

/* Keep irq disabled to prevent changes to the clock */
local_irq_save(flags);
--
1.6.0.6

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