ARM: 7862/1: pcpu: replace __get_cpu_var_uses

This is the ARM part of Christoph's patchset cleaning up the various
uses of __get_cpu_var across the tree.

The idea is to convert __get_cpu_var into either an explicit address
calculation using this_cpu_ptr() or into a use of this_cpu operations
that use the offset. Thereby address calculations are avoided and fewer
registers are used when code is generated.

[will: fixed debug ref counting checks and pcpu array accesses]

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/kvm/arm.c

@@ -65,7 +65,7 @@ static bool vgic_present;
 static void kvm_arm_set_running_vcpu(struct kvm_vcpu *vcpu)
 {
 	BUG_ON(preemptible());
-	__get_cpu_var(kvm_arm_running_vcpu) = vcpu;
+	__this_cpu_write(kvm_arm_running_vcpu, vcpu);
 }
 
 /**
@@ -75,7 +75,7 @@ static void kvm_arm_set_running_vcpu(struct kvm_vcpu *vcpu)
 struct kvm_vcpu *kvm_arm_get_running_vcpu(void)
 {
 	BUG_ON(preemptible());
-	return __get_cpu_var(kvm_arm_running_vcpu);
+	return __this_cpu_read(kvm_arm_running_vcpu);
 }
 
 /**
@@ -815,7 +815,7 @@ static void cpu_init_hyp_mode(void *dummy)
 
 	boot_pgd_ptr = kvm_mmu_get_boot_httbr();
 	pgd_ptr = kvm_mmu_get_httbr();
-	stack_page = __get_cpu_var(kvm_arm_hyp_stack_page);
+	stack_page = __this_cpu_read(kvm_arm_hyp_stack_page);
 	hyp_stack_ptr = stack_page + PAGE_SIZE;
 	vector_ptr = (unsigned long)__kvm_hyp_vector;