Message ID | 20191010110518.129256-3-borntraeger@de.ibm.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | diag 9c improvements | expand |
On Thu, 10 Oct 2019 13:05:18 +0200 Christian Borntraeger <borntraeger@de.ibm.com> wrote: > If the target is already running we do not need to yield. > > Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> > Reviewed-by: David Hildenbrand <david@redhat.com> > --- > arch/s390/kvm/diag.c | 4 ++++ > 1 file changed, 4 insertions(+) Reviewed-by: Cornelia Huck <cohuck@redhat.com>
diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c index 609c55df3ce8..3fb54ec2cf3e 100644 --- a/arch/s390/kvm/diag.c +++ b/arch/s390/kvm/diag.c @@ -168,6 +168,10 @@ static int __diag_time_slice_end_directed(struct kvm_vcpu *vcpu) if (!tcpu) goto no_yield; + /* target already running */ + if (READ_ONCE(tcpu->cpu) >= 0) + goto no_yield; + if (kvm_vcpu_yield_to(tcpu) <= 0) goto no_yield;