KVM: s390: move vcpu wakeup code to a central point

[pandora-kernel.git] / arch / s390 / kvm / interrupt.c

diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 90c8de2..65396e1 100644 (file)
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -544,13 +544,13 @@ int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu)
        int rc = 0;
 
        if (atomic_read(&li->active)) {
-               spin_lock_bh(&li->lock);
+               spin_lock(&li->lock);
                list_for_each_entry(inti, &li->list, list)
                        if (__interrupt_is_deliverable(vcpu, inti)) {
                                rc = 1;
                                break;
                        }
-               spin_unlock_bh(&li->lock);
+               spin_unlock(&li->lock);
        }
 
        if ((!rc) && atomic_read(&fi->active)) {
@@ -585,75 +585,54 @@ int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
 int kvm_s390_handle_wait(struct kvm_vcpu *vcpu)
 {
        u64 now, sltime;
-       DECLARE_WAITQUEUE(wait, current);
 
        vcpu->stat.exit_wait_state++;
-       if (kvm_cpu_has_interrupt(vcpu))
-               return 0;
 
-       __set_cpu_idle(vcpu);
-       spin_lock_bh(&vcpu->arch.local_int.lock);
-       vcpu->arch.local_int.timer_due = 0;
-       spin_unlock_bh(&vcpu->arch.local_int.lock);
+       /* fast path */
+       if (kvm_cpu_has_pending_timer(vcpu) || kvm_arch_vcpu_runnable(vcpu))
+               return 0;
 
        if (psw_interrupts_disabled(vcpu)) {
                VCPU_EVENT(vcpu, 3, "%s", "disabled wait");
-               __unset_cpu_idle(vcpu);
                return -EOPNOTSUPP; /* disabled wait */
        }
 
+       __set_cpu_idle(vcpu);
        if (!ckc_interrupts_enabled(vcpu)) {
                VCPU_EVENT(vcpu, 3, "%s", "enabled wait w/o timer");
                goto no_timer;
        }
 
        now = get_tod_clock_fast() + vcpu->arch.sie_block->epoch;
-       if (vcpu->arch.sie_block->ckc < now) {
-               __unset_cpu_idle(vcpu);
-               return 0;
-       }
-
        sltime = tod_to_ns(vcpu->arch.sie_block->ckc - now);
-
        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:
        srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
-       spin_lock(&vcpu->arch.local_int.float_int->lock);
-       spin_lock_bh(&vcpu->arch.local_int.lock);
-       add_wait_queue(&vcpu->wq, &wait);
-       while (list_empty(&vcpu->arch.local_int.list) &&
-               list_empty(&vcpu->arch.local_int.float_int->list) &&
-               (!vcpu->arch.local_int.timer_due) &&
-               !signal_pending(current) &&
-               !kvm_s390_si_ext_call_pending(vcpu)) {
-               set_current_state(TASK_INTERRUPTIBLE);
-               spin_unlock_bh(&vcpu->arch.local_int.lock);
-               spin_unlock(&vcpu->arch.local_int.float_int->lock);
-               schedule();
-               spin_lock(&vcpu->arch.local_int.float_int->lock);
-               spin_lock_bh(&vcpu->arch.local_int.lock);
-       }
+       kvm_vcpu_block(vcpu);
        __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(&vcpu->arch.local_int.float_int->lock);
        vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 
        hrtimer_try_to_cancel(&vcpu->arch.ckc_timer);
        return 0;
 }
 
+void kvm_s390_vcpu_wakeup(struct kvm_vcpu *vcpu)
+{
+       if (waitqueue_active(&vcpu->wq)) {
+               /*
+                * The vcpu gave up the cpu voluntarily, mark it as a good
+                * yield-candidate.
+                */
+               vcpu->preempted = true;
+               wake_up_interruptible(&vcpu->wq);
+       }
+}
+
 void kvm_s390_tasklet(unsigned long parm)
 {
        struct kvm_vcpu *vcpu = (struct kvm_vcpu *) parm;
-
-       spin_lock(&vcpu->arch.local_int.lock);
-       vcpu->arch.local_int.timer_due = 1;
-       if (waitqueue_active(&vcpu->wq))
-               wake_up_interruptible(&vcpu->wq);
-       spin_unlock(&vcpu->arch.local_int.lock);
+       kvm_s390_vcpu_wakeup(vcpu);
 }
 
 /*
@@ -676,13 +655,13 @@ void kvm_s390_clear_local_irqs(struct kvm_vcpu *vcpu)
        struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
        struct kvm_s390_interrupt_info  *n, *inti = NULL;
 
-       spin_lock_bh(&li->lock);
+       spin_lock(&li->lock);
        list_for_each_entry_safe(inti, n, &li->list, list) {
                list_del(&inti->list);
                kfree(inti);
        }
        atomic_set(&li->active, 0);
-       spin_unlock_bh(&li->lock);
+       spin_unlock(&li->lock);
 
        /* clear pending external calls set by sigp interpretation facility */
        atomic_clear_mask(CPUSTAT_ECALL_PEND, &vcpu->arch.sie_block->cpuflags);
@@ -701,7 +680,7 @@ void kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
        if (atomic_read(&li->active)) {
                do {
                        deliver = 0;
-                       spin_lock_bh(&li->lock);
+                       spin_lock(&li->lock);
                        list_for_each_entry_safe(inti, n, &li->list, list) {
                                if (__interrupt_is_deliverable(vcpu, inti)) {
                                        list_del(&inti->list);
@@ -712,7 +691,7 @@ void kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
                        }
                        if (list_empty(&li->list))
                                atomic_set(&li->active, 0);
-                       spin_unlock_bh(&li->lock);
+                       spin_unlock(&li->lock);
                        if (deliver) {
                                __do_deliver_interrupt(vcpu, inti);
                                kfree(inti);
@@ -758,7 +737,7 @@ void kvm_s390_deliver_pending_machine_checks(struct kvm_vcpu *vcpu)
        if (atomic_read(&li->active)) {
                do {
                        deliver = 0;
-                       spin_lock_bh(&li->lock);
+                       spin_lock(&li->lock);
                        list_for_each_entry_safe(inti, n, &li->list, list) {
                                if ((inti->type == KVM_S390_MCHK) &&
                                    __interrupt_is_deliverable(vcpu, inti)) {
@@ -770,7 +749,7 @@ void kvm_s390_deliver_pending_machine_checks(struct kvm_vcpu *vcpu)
                        }
                        if (list_empty(&li->list))
                                atomic_set(&li->active, 0);
-                       spin_unlock_bh(&li->lock);
+                       spin_unlock(&li->lock);
                        if (deliver) {
                                __do_deliver_interrupt(vcpu, inti);
                                kfree(inti);
@@ -817,11 +796,11 @@ int kvm_s390_inject_program_int(struct kvm_vcpu *vcpu, u16 code)
 
        VCPU_EVENT(vcpu, 3, "inject: program check %d (from kernel)", code);
        trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, inti->type, code, 0, 1);
-       spin_lock_bh(&li->lock);
+       spin_lock(&li->lock);
        list_add(&inti->list, &li->list);
        atomic_set(&li->active, 1);
        BUG_ON(waitqueue_active(li->wq));
-       spin_unlock_bh(&li->lock);
+       spin_unlock(&li->lock);
        return 0;
 }
 
@@ -842,11 +821,11 @@ int kvm_s390_inject_prog_irq(struct kvm_vcpu *vcpu,
 
        inti->type = KVM_S390_PROGRAM_INT;
        memcpy(&inti->pgm, pgm_info, sizeof(inti->pgm));
-       spin_lock_bh(&li->lock);
+       spin_lock(&li->lock);
        list_add(&inti->list, &li->list);
        atomic_set(&li->active, 1);
        BUG_ON(waitqueue_active(li->wq));
-       spin_unlock_bh(&li->lock);
+       spin_unlock(&li->lock);
        return 0;
 }
 
@@ -934,12 +913,10 @@ static int __inject_vm(struct kvm *kvm, struct kvm_s390_interrupt_info *inti)
        }
        dst_vcpu = kvm_get_vcpu(kvm, sigcpu);
        li = &dst_vcpu->arch.local_int;
-       spin_lock_bh(&li->lock);
+       spin_lock(&li->lock);
        atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
-       if (waitqueue_active(li->wq))
-               wake_up_interruptible(li->wq);
-       kvm_get_vcpu(kvm, sigcpu)->preempted = true;
-       spin_unlock_bh(&li->lock);
+       spin_unlock(&li->lock);
+       kvm_s390_vcpu_wakeup(kvm_get_vcpu(kvm, sigcpu));
 unlock_fi:
        spin_unlock(&fi->lock);
        mutex_unlock(&kvm->lock);
@@ -1081,7 +1058,7 @@ int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
 
        mutex_lock(&vcpu->kvm->lock);
        li = &vcpu->arch.local_int;
-       spin_lock_bh(&li->lock);
+       spin_lock(&li->lock);
        if (inti->type == KVM_S390_PROGRAM_INT)
                list_add(&inti->list, &li->list);
        else
@@ -1090,11 +1067,9 @@ int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
        if (inti->type == KVM_S390_SIGP_STOP)
                li->action_bits |= ACTION_STOP_ON_STOP;
        atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
-       if (waitqueue_active(&vcpu->wq))
-               wake_up_interruptible(&vcpu->wq);
-       vcpu->preempted = true;
-       spin_unlock_bh(&li->lock);
+       spin_unlock(&li->lock);
        mutex_unlock(&vcpu->kvm->lock);
+       kvm_s390_vcpu_wakeup(vcpu);
        return 0;
 }