From: David Hildenbrand <[email protected]> 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 <[email protected]> Acked-by: Christian Borntraeger <[email protected]> Acked-by: Cornelia Huck <[email protected]> Signed-off-by: Christian Borntraeger <[email protected]> --- arch/s390/include/asm/kvm_host.h | 1 - arch/s390/kvm/interrupt.c | 41 +++++----------------------------------- arch/s390/kvm/kvm-s390.c | 3 +++ 3 files changed, 8 insertions(+), 37 deletions(-) diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h index c2ba020..b3acf28 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -305,7 +305,6 @@ struct kvm_s390_local_interrupt { struct list_head list; atomic_t active; struct kvm_s390_float_interrupt *float_int; - int timer_due; /* event indicator for waitqueue below */ wait_queue_head_t *wq; atomic_t *cpuflags; unsigned int action_bits; 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_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); @@ -649,11 +621,8 @@ 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); } /* diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index fdf88f7..ecb1357 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -1068,6 +1068,9 @@ retry: goto retry; } + /* nothing to do, just clear the request */ + clear_bit(KVM_REQ_UNHALT, &vcpu->requests); + return 0; } -- 1.8.4.2 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
