KVM: s390: optimize float int lock: spin_lock_bh --> spin_lock

The floating interrupt lock is only taken in process context. We can
replace all spin_lock_bh with standard spin_lock calls.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Ehrhardt <ehrhardt@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index a48830f..f04f530 100644 (file)
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -301,13 +301,13 @@ int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu)
        }
 
        if ((!rc) && atomic_read(&fi->active)) {
-               spin_lock_bh(&fi->lock);
+               spin_lock(&fi->lock);
                list_for_each_entry(inti, &fi->list, list)
                        if (__interrupt_is_deliverable(vcpu, inti)) {
                                rc = 1;
                                break;
                        }
-               spin_unlock_bh(&fi->lock);
+               spin_unlock(&fi->lock);
        }
 
        if ((!rc) && (vcpu->arch.sie_block->ckc <
@@ -368,7 +368,7 @@ int kvm_s390_handle_wait(struct kvm_vcpu *vcpu)
        hrtimer_start(&vcpu->arch.ckc_timer, ktime_set (0, sltime) , HRTIMER_MODE_REL);
        VCPU_EVENT(vcpu, 5, "enabled wait via clock comparator: %llx ns", sltime);
 no_timer:
-       spin_lock_bh(&vcpu->arch.local_int.float_int->lock);
+       spin_lock(&vcpu->arch.local_int.float_int->lock);
        spin_lock_bh(&vcpu->arch.local_int.lock);
        add_wait_queue(&vcpu->arch.local_int.wq, &wait);
        while (list_empty(&vcpu->arch.local_int.list) &&
@@ -377,18 +377,18 @@ no_timer:
                !signal_pending(current)) {
                set_current_state(TASK_INTERRUPTIBLE);
                spin_unlock_bh(&vcpu->arch.local_int.lock);
-               spin_unlock_bh(&vcpu->arch.local_int.float_int->lock);
+               spin_unlock(&vcpu->arch.local_int.float_int->lock);
                vcpu_put(vcpu);
                schedule();
                vcpu_load(vcpu);
-               spin_lock_bh(&vcpu->arch.local_int.float_int->lock);
+               spin_lock(&vcpu->arch.local_int.float_int->lock);
                spin_lock_bh(&vcpu->arch.local_int.lock);
        }
        __unset_cpu_idle(vcpu);
        __set_current_state(TASK_RUNNING);
        remove_wait_queue(&vcpu->wq, &wait);
        spin_unlock_bh(&vcpu->arch.local_int.lock);
-       spin_unlock_bh(&vcpu->arch.local_int.float_int->lock);
+       spin_unlock(&vcpu->arch.local_int.float_int->lock);
        hrtimer_try_to_cancel(&vcpu->arch.ckc_timer);
        return 0;
 }
@@ -455,7 +455,7 @@ void kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
        if (atomic_read(&fi->active)) {
                do {
                        deliver = 0;
-                       spin_lock_bh(&fi->lock);
+                       spin_lock(&fi->lock);
                        list_for_each_entry_safe(inti, n, &fi->list, list) {
                                if (__interrupt_is_deliverable(vcpu, inti)) {
                                        list_del(&inti->list);
@@ -466,7 +466,7 @@ void kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
                        }
                        if (list_empty(&fi->list))
                                atomic_set(&fi->active, 0);
-                       spin_unlock_bh(&fi->lock);
+                       spin_unlock(&fi->lock);
                        if (deliver) {
                                __do_deliver_interrupt(vcpu, inti);
                                kfree(inti);
@@ -531,7 +531,7 @@ int kvm_s390_inject_vm(struct kvm *kvm,
 
        mutex_lock(&kvm->lock);
        fi = &kvm->arch.float_int;
-       spin_lock_bh(&fi->lock);
+       spin_lock(&fi->lock);
        list_add_tail(&inti->list, &fi->list);
        atomic_set(&fi->active, 1);
        sigcpu = find_first_bit(fi->idle_mask, KVM_MAX_VCPUS);
@@ -548,7 +548,7 @@ int kvm_s390_inject_vm(struct kvm *kvm,
        if (waitqueue_active(&li->wq))
                wake_up_interruptible(&li->wq);
        spin_unlock_bh(&li->lock);
-       spin_unlock_bh(&fi->lock);
+       spin_unlock(&fi->lock);
        mutex_unlock(&kvm->lock);
        return 0;
 }

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index dc3d068..36c654d 100644 (file)
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -318,11 +318,11 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm,
        spin_lock_init(&vcpu->arch.local_int.lock);
        INIT_LIST_HEAD(&vcpu->arch.local_int.list);
        vcpu->arch.local_int.float_int = &kvm->arch.float_int;
-       spin_lock_bh(&kvm->arch.float_int.lock);
+       spin_lock(&kvm->arch.float_int.lock);
        kvm->arch.float_int.local_int[id] = &vcpu->arch.local_int;
        init_waitqueue_head(&vcpu->arch.local_int.wq);
        vcpu->arch.local_int.cpuflags = &vcpu->arch.sie_block->cpuflags;
-       spin_unlock_bh(&kvm->arch.float_int.lock);
+       spin_unlock(&kvm->arch.float_int.lock);
 
        rc = kvm_vcpu_init(vcpu, kvm, id);
        if (rc)

diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
index 4b88834..93ecd06 100644 (file)
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -204,11 +204,11 @@ static void handle_stsi_3_2_2(struct kvm_vcpu *vcpu, struct sysinfo_3_2_2 *mem)
        int cpus = 0;
        int n;
 
-       spin_lock_bh(&fi->lock);
+       spin_lock(&fi->lock);
        for (n = 0; n < KVM_MAX_VCPUS; n++)
                if (fi->local_int[n])
                        cpus++;
-       spin_unlock_bh(&fi->lock);
+       spin_unlock(&fi->lock);
 
        /* deal with other level 3 hypervisors */
        if (stsi(mem, 3, 2, 2) == -ENOSYS)

diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c
index f27dbed..3667883 100644 (file)
--- a/arch/s390/kvm/sigp.c
+++ b/arch/s390/kvm/sigp.c
@@ -52,7 +52,7 @@ static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
        if (cpu_addr >= KVM_MAX_VCPUS)
                return 3; /* not operational */
 
-       spin_lock_bh(&fi->lock);
+       spin_lock(&fi->lock);
        if (fi->local_int[cpu_addr] == NULL)
                rc = 3; /* not operational */
        else if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
@@ -64,7 +64,7 @@ static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
                *reg |= SIGP_STAT_STOPPED;
                rc = 1; /* status stored */
        }
-       spin_unlock_bh(&fi->lock);
+       spin_unlock(&fi->lock);
 
        VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", cpu_addr, rc);
        return rc;
@@ -86,7 +86,7 @@ static int __sigp_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr)
 
        inti->type = KVM_S390_INT_EMERGENCY;
 
-       spin_lock_bh(&fi->lock);
+       spin_lock(&fi->lock);
        li = fi->local_int[cpu_addr];
        if (li == NULL) {
                rc = 3; /* not operational */
@@ -102,7 +102,7 @@ static int __sigp_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr)
        spin_unlock_bh(&li->lock);
        rc = 0; /* order accepted */
 unlock:
-       spin_unlock_bh(&fi->lock);
+       spin_unlock(&fi->lock);
        VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);
        return rc;
 }
@@ -123,7 +123,7 @@ static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int store)
 
        inti->type = KVM_S390_SIGP_STOP;
 
-       spin_lock_bh(&fi->lock);
+       spin_lock(&fi->lock);
        li = fi->local_int[cpu_addr];
        if (li == NULL) {
                rc = 3; /* not operational */
@@ -142,7 +142,7 @@ static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int store)
        spin_unlock_bh(&li->lock);
        rc = 0; /* order accepted */
 unlock:
-       spin_unlock_bh(&fi->lock);
+       spin_unlock(&fi->lock);
        VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
        return rc;
 }
@@ -188,7 +188,7 @@ static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
        if (!inti)
                return 2; /* busy */
 
-       spin_lock_bh(&fi->lock);
+       spin_lock(&fi->lock);
        li = fi->local_int[cpu_addr];
 
        if ((cpu_addr >= KVM_MAX_VCPUS) || (li == NULL)) {
@@ -220,7 +220,7 @@ static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
 out_li:
        spin_unlock_bh(&li->lock);
 out_fi:
-       spin_unlock_bh(&fi->lock);
+       spin_unlock(&fi->lock);
        return rc;
 }