From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34115) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dSKEF-0001qc-Mq for qemu-devel@nongnu.org; Tue, 04 Jul 2017 05:34:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dSKE9-0007Zb-Ir for qemu-devel@nongnu.org; Tue, 04 Jul 2017 05:34:43 -0400 Date: Tue, 4 Jul 2017 11:34:19 +0200 From: Cornelia Huck Message-ID: <20170704113419.1218ce97@dhcp-192-215.str.redhat.com> In-Reply-To: <20170704083231.98056-2-haoqf@linux.vnet.ibm.com> References: <20170704083231.98056-1-haoqf@linux.vnet.ibm.com> <20170704083231.98056-2-haoqf@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v3 1/1] virtio-scsi-ccw: use ioeventfd even when KVM is disabled List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: QingFeng Hao Cc: qemu-devel@nongnu.org, qemu-block@nongnu.org, borntraeger@de.ibm.com, zyimin@linux.vnet.ibm.com, stefanha@redhat.com, kwolf@redhat.com, famz@redhat.com, peterx@redhat.com On Tue, 4 Jul 2017 10:32:31 +0200 QingFeng Hao wrote: > This patch is based on a similar patch from Stefan Hajnoczi - > commit c324fd0a39c (" virtio-pci: use ioeventfd even when KVM is disabled) > > Do not check kvm_eventfds_enabled() when KVM is disabled since it > always returns 0. Since commit 8c56c1a592b5092d91da8d8943c17777d6462a6f > ("memory: emulate ioeventfd") it has been possible to use ioeventfds in > qtest or TCG mode. > > This patch makes -device virtio-scsi-ccw,iothread=iothread0 work even > when KVM is disabled. It might be good to add a sentence that we don't have an equivalent to "memory: emulate ioeventfd" for ccw yet, but that this doesn't hurt. > > I have tested that virtio-scsi-ccw works under tcg both with and without > iothread. > > This patch fixes qemu-iotests 068, which was accidentally merged early > despite the dependency on ioeventfd. > > Signed-off-by: QingFeng Hao > --- > hw/s390x/virtio-ccw.c | 2 +- > target/s390x/cpu.h | 6 +++++- > 2 files changed, 6 insertions(+), 2 deletions(-) > > diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c > index 90d37cb9ff..35896eb007 100644 > --- a/hw/s390x/virtio-ccw.c > +++ b/hw/s390x/virtio-ccw.c > @@ -711,7 +711,7 @@ static void virtio_ccw_device_realize(VirtioCcwDevice *dev, Error **errp) > sch->cssid, sch->ssid, sch->schid, sch->devno, > ccw_dev->devno.valid ? "user-configured" : "auto-configured"); > > - if (!kvm_eventfds_enabled()) { > + if (kvm_enabled() && !kvm_eventfds_enabled()) { > dev->flags &= ~VIRTIO_CCW_FLAG_USE_IOEVENTFD; > } > > diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h > index 9faca04b52..bdb9bdbc9d 100644 > --- a/target/s390x/cpu.h > +++ b/target/s390x/cpu.h > @@ -1264,7 +1264,11 @@ static inline int s390_assign_subch_ioeventfd(EventNotifier *notifier, > uint32_t sch_id, int vq, > bool assign) > { > - return kvm_s390_assign_subch_ioeventfd(notifier, sch_id, vq, assign); > + if (kvm_enabled()) { > + return kvm_s390_assign_subch_ioeventfd(notifier, sch_id, vq, assign); > + } else { > + return 0; > + } > } > > static inline void s390_crypto_reset(void) Reviewed-by: Cornelia Huck