[PATCH 2/3] kvm: use this_cpu_xxx replace percpu_xxx funcs

From: Alex,Shi
Date: Thu Oct 20 2011 - 03:31:05 EST


percpu_xxx funcs are duplicated with this_cpu_xxx funcs, so replace them
for further code clean up.

And in preempt safe scenario, __this_cpu_xxx funcs has a bit better
performance since __this_cpu_xxx has no redundant preempt_disable()

Signed-off-by: Alex Shi <alex.shi@xxxxxxxxx>
---
arch/x86/kvm/x86.c | 14 +++++++-------
1 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 84a28ea..432c4bc 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5024,15 +5024,15 @@ static DEFINE_PER_CPU(struct kvm_vcpu *, current_vcpu);

static int kvm_is_in_guest(void)
{
- return percpu_read(current_vcpu) != NULL;
+ return __this_cpu_read(current_vcpu) != NULL;
}

static int kvm_is_user_mode(void)
{
int user_mode = 3;

- if (percpu_read(current_vcpu))
- user_mode = kvm_x86_ops->get_cpl(percpu_read(current_vcpu));
+ if (__this_cpu_read(current_vcpu))
+ user_mode = kvm_x86_ops->get_cpl(__this_cpu_read(current_vcpu));

return user_mode != 0;
}
@@ -5041,8 +5041,8 @@ static unsigned long kvm_get_guest_ip(void)
{
unsigned long ip = 0;

- if (percpu_read(current_vcpu))
- ip = kvm_rip_read(percpu_read(current_vcpu));
+ if (__this_cpu_read(current_vcpu))
+ ip = kvm_rip_read(__this_cpu_read(current_vcpu));

return ip;
}
@@ -5055,13 +5055,13 @@ static struct perf_guest_info_callbacks kvm_guest_cbs = {

void kvm_before_handle_nmi(struct kvm_vcpu *vcpu)
{
- percpu_write(current_vcpu, vcpu);
+ __this_cpu_write(current_vcpu, vcpu);
}
EXPORT_SYMBOL_GPL(kvm_before_handle_nmi);

void kvm_after_handle_nmi(struct kvm_vcpu *vcpu)
{
- percpu_write(current_vcpu, NULL);
+ __this_cpu_write(current_vcpu, NULL);
}
EXPORT_SYMBOL_GPL(kvm_after_handle_nmi);

--
1.6.3.3



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