[GIT PULL 3/9] KVM: s390: remove _bh locking from start_stop_lock

Christian Borntraeger
2014-07-21T19:14:19Z

From: David Hildenbrand <dahi@linux.vnet.ibm.com>

The start_stop_lock is no longer acquired when in atomic context, therefore we
can convert it into an ordinary spin_lock.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/kvm/kvm-s390.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index a7bda18..b29a031 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -1478,7 +1478,7 @@ void kvm_s390_vcpu_start(struct kvm_vcpu *vcpu)

trace_kvm_s390_vcpu_start_stop(vcpu->vcpu_id, 1);
/* Only one cpu at a time may enter/leave the STOPPED state. */
- spin_lock_bh(&vcpu->kvm->arch.start_stop_lock);
+ spin_lock(&vcpu->kvm->arch.start_stop_lock);
online_vcpus = atomic_read(&vcpu->kvm->online_vcpus);

for (i = 0; i < online_vcpus; i++) {
@@ -1504,7 +1504,7 @@ void kvm_s390_vcpu_start(struct kvm_vcpu *vcpu)
* Let's play safe and flush the VCPU at startup.
*/
vcpu->arch.sie_block->ihcpu = 0xffff;
- spin_unlock_bh(&vcpu->kvm->arch.start_stop_lock);
+ spin_unlock(&vcpu->kvm->arch.start_stop_lock);
return;
}

@@ -1518,7 +1518,7 @@ void kvm_s390_vcpu_stop(struct kvm_vcpu *vcpu)

trace_kvm_s390_vcpu_start_stop(vcpu->vcpu_id, 0);
/* Only one cpu at a time may enter/leave the STOPPED state. */
- spin_lock_bh(&vcpu->kvm->arch.start_stop_lock);
+ spin_lock(&vcpu->kvm->arch.start_stop_lock);
online_vcpus = atomic_read(&vcpu->kvm->online_vcpus);

/* Need to lock access to action_bits to avoid a SIGP race condition */
@@ -1547,7 +1547,7 @@ void kvm_s390_vcpu_stop(struct kvm_vcpu *vcpu)
__enable_ibs_on_vcpu(started_vcpu);
}

- spin_unlock_bh(&vcpu->kvm->arch.start_stop_lock);
+ spin_unlock(&vcpu->kvm->arch.start_stop_lock);
return;
}

--
1.8.4.2