KVM: s390: cleanup handle_wait by reusing kvm_vcpu_block
This patch cleans up the code in handle_wait by reusing the common code
function kvm_vcpu_block.
signal_pending(), kvm_cpu_has_pending_timer() and kvm_arch_vcpu_runnable() are
sufficient for checking if we need to wake-up that VCPU. kvm_vcpu_block
uses these functions, so no checks are lost.
The flag "timer_due" can be removed - kvm_cpu_has_pending_timer() tests whether
the timer is pending, thus the vcpu is correctly woken up.
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-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>
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 90c8de2..5fd11ce 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -585,60 +585,32 @@
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);
@@ -649,11 +621,8 @@
{
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);
}
/*