[RFC PATCH 8/9] arm: KVM: timer: move the timer switch into the non-preemptible section

From: Marc Zyngier
Date: Wed Jun 25 2014 - 05:30:53 EST


In order to convert the timer code to the new interrupt save/restore API,
make sure the timer switch is done in a non-premtible section, so that
we save/restore the state on the right CPU.

Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
---
arch/arm/kvm/arm.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index a291e63..92875b2 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -554,9 +554,9 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
vcpu_pause(vcpu);

kvm_vgic_flush_hwstate(vcpu);
- kvm_timer_flush_hwstate(vcpu);

local_irq_disable();
+ kvm_timer_flush_hwstate(vcpu);

/*
* Re-check atomic conditions
@@ -567,8 +567,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
}

if (ret <= 0 || need_new_vmid_gen(vcpu->kvm)) {
- local_irq_enable();
kvm_timer_sync_hwstate(vcpu);
+ local_irq_enable();
kvm_vgic_sync_hwstate(vcpu);
continue;
}
@@ -586,6 +586,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
vcpu->arch.last_pcpu = smp_processor_id();
kvm_guest_exit();
trace_kvm_exit(*vcpu_pc(vcpu));
+ kvm_timer_sync_hwstate(vcpu);
+
/*
* We may have taken a host interrupt in HYP mode (ie
* while executing the guest). This interrupt is still
@@ -602,7 +604,6 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
* Back from guest
*************************************************************/

- kvm_timer_sync_hwstate(vcpu);
kvm_vgic_sync_hwstate(vcpu);

ret = handle_exit(vcpu, run, ret);
--
1.8.3.4

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