| Message ID | 1424934286-7099-4-git-send-email-jasowang@redhat.com |
|---|---|
| State | New |
| Headers | show |
On Thu, Feb 26, 2015 at 03:04:38PM +0800, Jason Wang wrote: > This patch introduces a bus specific queue limitation. It will be > useful for increasing the limit for one of the bus without disturbing > other buses. Is this about s390 only supporting up to 64 queues? > > Cc: Anthony Liguori <aliguori@amazon.com> > Cc: Michael S. Tsirkin <mst@redhat.com> > Cc: Alexander Graf <agraf@suse.de> > Cc: Richard Henderson <rth@twiddle.net> > Cc: Cornelia Huck <cornelia.huck@de.ibm.com> > Cc: Christian Borntraeger <borntraeger@de.ibm.com> > Cc: Paolo Bonzini <pbonzini@redhat.com> > Signed-off-by: Jason Wang <jasowang@redhat.com> > --- > hw/net/virtio-net.c | 4 ++-- > hw/s390x/s390-virtio-bus.c | 1 + > hw/s390x/virtio-ccw.c | 1 + > hw/scsi/virtio-scsi.c | 4 ++-- > hw/virtio/virtio-mmio.c | 1 + > hw/virtio/virtio-pci.c | 1 + > hw/virtio/virtio.c | 52 +++++++++++++++++++++++++++++++----------- > include/hw/virtio/virtio-bus.h | 1 + > include/hw/virtio/virtio.h | 1 + > 9 files changed, 49 insertions(+), 17 deletions(-) > > diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c > index c8d2cca..260345c 100644 > --- a/hw/net/virtio-net.c > +++ b/hw/net/virtio-net.c > @@ -1585,10 +1585,10 @@ static void virtio_net_device_realize(DeviceState *dev, Error **errp) > virtio_init(vdev, "virtio-net", VIRTIO_ID_NET, n->config_size); > > n->max_queues = MAX(n->nic_conf.peers.queues, 1); > - if (n->max_queues * 2 + 1 > VIRTIO_PCI_QUEUE_MAX) { > + if (n->max_queues * 2 + 1 > virtio_get_queue_max(vdev)) { > error_setg(errp, "Invalid number of queues (= %" PRIu32 "), " > "must be a postive integer less than %d.", > - n->max_queues, (VIRTIO_PCI_QUEUE_MAX - 1) / 2); > + n->max_queues, (virtio_get_queue_max(vdev) - 1) / 2); > virtio_cleanup(vdev); > return; > } > diff --git a/hw/s390x/s390-virtio-bus.c b/hw/s390x/s390-virtio-bus.c > index 39dc201..d48590a 100644 > --- a/hw/s390x/s390-virtio-bus.c > +++ b/hw/s390x/s390-virtio-bus.c > @@ -707,6 +707,7 @@ static void virtio_s390_bus_class_init(ObjectClass *klass, void *data) > bus_class->max_dev = 1; > k->notify = virtio_s390_notify; > k->get_features = virtio_s390_get_features; > + k->queue_max = VIRTIO_PCI_QUEUE_MAX; > } > > static const TypeInfo virtio_s390_bus_info = { > diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c > index ea236c9..4874622 100644 > --- a/hw/s390x/virtio-ccw.c > +++ b/hw/s390x/virtio-ccw.c > @@ -1695,6 +1695,7 @@ static void virtio_ccw_bus_class_init(ObjectClass *klass, void *data) > k->load_queue = virtio_ccw_load_queue; > k->save_config = virtio_ccw_save_config; > k->load_config = virtio_ccw_load_config; > + k->queue_max = VIRTIO_PCI_QUEUE_MAX; > } > > static const TypeInfo virtio_ccw_bus_info = { > diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c > index 9e2c718..91d49f1 100644 > --- a/hw/scsi/virtio-scsi.c > +++ b/hw/scsi/virtio-scsi.c > @@ -822,10 +822,10 @@ void virtio_scsi_common_realize(DeviceState *dev, Error **errp, > sizeof(VirtIOSCSIConfig)); > > if (s->conf.num_queues == 0 || > - s->conf.num_queues > VIRTIO_PCI_QUEUE_MAX - 2) { > + s->conf.num_queues > virtio_get_queue_max(vdev) - 2) { > error_setg(errp, "Invalid number of queues (= %" PRIu32 "), " > "must be a positive integer less than %d.", > - s->conf.num_queues, VIRTIO_PCI_QUEUE_MAX - 2); > + s->conf.num_queues, virtio_get_queue_max(vdev) - 2); > virtio_cleanup(vdev); > return; > } > diff --git a/hw/virtio/virtio-mmio.c b/hw/virtio/virtio-mmio.c > index 2450c13..ad03218 100644 > --- a/hw/virtio/virtio-mmio.c > +++ b/hw/virtio/virtio-mmio.c > @@ -403,6 +403,7 @@ static void virtio_mmio_bus_class_init(ObjectClass *klass, void *data) > k->device_plugged = virtio_mmio_device_plugged; > k->has_variable_vring_alignment = true; > bus_class->max_dev = 1; > + k->queue_max = VIRTIO_PCI_QUEUE_MAX; > } > > static const TypeInfo virtio_mmio_bus_info = { > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > index dde1d73..7fa8141 100644 > --- a/hw/virtio/virtio-pci.c > +++ b/hw/virtio/virtio-pci.c > @@ -1559,6 +1559,7 @@ static void virtio_pci_bus_class_init(ObjectClass *klass, void *data) > k->vmstate_change = virtio_pci_vmstate_change; > k->device_plugged = virtio_pci_device_plugged; > k->device_unplugged = virtio_pci_device_unplugged; > + k->queue_max = VIRTIO_PCI_QUEUE_MAX; > } > > static const TypeInfo virtio_pci_bus_info = { > diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > index ffc22e8..5a806b5 100644 > --- a/hw/virtio/virtio.c > +++ b/hw/virtio/virtio.c > @@ -541,6 +541,14 @@ void virtio_update_irq(VirtIODevice *vdev) > virtio_notify_vector(vdev, VIRTIO_NO_VECTOR); > } > > +int virtio_get_queue_max(VirtIODevice *vdev) > +{ > + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); > + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); > + > + return k->queue_max; > +} > + > void virtio_set_status(VirtIODevice *vdev, uint8_t val) > { > VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); > @@ -576,6 +584,8 @@ static enum virtio_device_endian virtio_current_cpu_endian(void) > void virtio_reset(void *opaque) > { > VirtIODevice *vdev = opaque; > + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); > + VirtioBusClass *bk = VIRTIO_BUS_GET_CLASS(qbus); > VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); > int i; > > @@ -599,7 +609,7 @@ void virtio_reset(void *opaque) > vdev->config_vector = VIRTIO_NO_VECTOR; > virtio_notify_vector(vdev, vdev->config_vector); > > - for(i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) { > + for(i = 0; i < bk->queue_max; i++) { > vdev->vq[i].vring.desc = 0; > vdev->vq[i].vring.avail = 0; > vdev->vq[i].vring.used = 0; > @@ -738,7 +748,10 @@ int virtio_queue_get_num(VirtIODevice *vdev, int n) > int virtio_queue_get_id(VirtQueue *vq) > { > VirtIODevice *vdev = vq->vdev; > - assert(vq >= &vdev->vq[0] && vq < &vdev->vq[VIRTIO_PCI_QUEUE_MAX]); > + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); > + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); > + > + assert(vq >= &vdev->vq[0] && vq < &vdev->vq[k->queue_max]); > return vq - &vdev->vq[0]; > } > > @@ -777,27 +790,35 @@ void virtio_queue_notify(VirtIODevice *vdev, int n) > > uint16_t virtio_queue_vector(VirtIODevice *vdev, int n) > { > - return n < VIRTIO_PCI_QUEUE_MAX ? vdev->vq[n].vector : > + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); > + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); > + > + return n < k->queue_max ? vdev->vq[n].vector : > VIRTIO_NO_VECTOR; > } > > void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector) > { > - if (n < VIRTIO_PCI_QUEUE_MAX) > + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); > + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); > + > + if (n < k->queue_max) > vdev->vq[n].vector = vector; > } > > VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size, > void (*handle_output)(VirtIODevice *, VirtQueue *)) > { > + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); > + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); > int i; > > - for (i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) { > + for (i = 0; i < k->queue_max; i++) { > if (vdev->vq[i].vring.num == 0) > break; > } > > - if (i == VIRTIO_PCI_QUEUE_MAX || queue_size > VIRTQUEUE_MAX_SIZE) > + if (i == k->queue_max || queue_size > VIRTQUEUE_MAX_SIZE) > abort(); > > vdev->vq[i].vring.num = queue_size; > @@ -809,7 +830,10 @@ VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size, > > void virtio_del_queue(VirtIODevice *vdev, int n) > { > - if (n < 0 || n >= VIRTIO_PCI_QUEUE_MAX) { > + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); > + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); > + > + if (n < 0 || n >= k->queue_max) { > abort(); > } > > @@ -932,14 +956,14 @@ void virtio_save(VirtIODevice *vdev, QEMUFile *f) > qemu_put_be32(f, vdev->config_len); > qemu_put_buffer(f, vdev->config, vdev->config_len); > > - for (i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) { > + for (i = 0; i < k->queue_max; i++) { > if (vdev->vq[i].vring.num == 0) > break; > } > > qemu_put_be32(f, i); > > - for (i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) { > + for (i = 0; i < k->queue_max; i++) { > if (vdev->vq[i].vring.num == 0) > break; > > @@ -1004,7 +1028,7 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id) > qemu_get_8s(f, &vdev->status); > qemu_get_8s(f, &vdev->isr); > qemu_get_be16s(f, &vdev->queue_sel); > - if (vdev->queue_sel >= VIRTIO_PCI_QUEUE_MAX) { > + if (vdev->queue_sel >= k->queue_max) { > return -1; > } > qemu_get_be32s(f, &features); > @@ -1031,7 +1055,7 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id) > > num = qemu_get_be32(f); > > - if (num > VIRTIO_PCI_QUEUE_MAX) { > + if (num > k->queue_max) { > error_report("Invalid number of PCI queues: 0x%x", num); > return -1; > } > @@ -1141,15 +1165,17 @@ void virtio_instance_init_common(Object *proxy_obj, void *data, > void virtio_init(VirtIODevice *vdev, const char *name, > uint16_t device_id, size_t config_size) > { > + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); > + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); > int i; > vdev->device_id = device_id; > vdev->status = 0; > vdev->isr = 0; > vdev->queue_sel = 0; > vdev->config_vector = VIRTIO_NO_VECTOR; > - vdev->vq = g_malloc0(sizeof(VirtQueue) * VIRTIO_PCI_QUEUE_MAX); > + vdev->vq = g_malloc0(sizeof(VirtQueue) * k->queue_max); > vdev->vm_running = runstate_is_running(); > - for (i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) { > + for (i = 0; i < k->queue_max; i++) { > vdev->vq[i].vector = VIRTIO_NO_VECTOR; > vdev->vq[i].vdev = vdev; > vdev->vq[i].queue_index = i; > diff --git a/include/hw/virtio/virtio-bus.h b/include/hw/virtio/virtio-bus.h > index 0756545..979835c 100644 > --- a/include/hw/virtio/virtio-bus.h > +++ b/include/hw/virtio/virtio-bus.h > @@ -68,6 +68,7 @@ typedef struct VirtioBusClass { > * Note that changing this will break migration for this transport. > */ > bool has_variable_vring_alignment; > + uint16_t queue_max; > } VirtioBusClass; > > struct VirtioBusState { > diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h > index f24997d..9fe0d92 100644 > --- a/include/hw/virtio/virtio.h > +++ b/include/hw/virtio/virtio.h > @@ -223,6 +223,7 @@ void virtio_queue_notify(VirtIODevice *vdev, int n); > uint16_t virtio_queue_vector(VirtIODevice *vdev, int n); > void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector); > void virtio_set_status(VirtIODevice *vdev, uint8_t val); > +int virtio_get_queue_max(VirtIODevice *vdev); > void virtio_reset(void *opaque); > void virtio_update_irq(VirtIODevice *vdev); > int virtio_set_features(VirtIODevice *vdev, uint32_t val); > -- > 1.9.1
On Thu, 26 Feb 2015 15:04:38 +0800 Jason Wang <jasowang@redhat.com> wrote: > This patch introduces a bus specific queue limitation. It will be > useful for increasing the limit for one of the bus without disturbing > other buses. > > Cc: Anthony Liguori <aliguori@amazon.com> > Cc: Michael S. Tsirkin <mst@redhat.com> > Cc: Alexander Graf <agraf@suse.de> > Cc: Richard Henderson <rth@twiddle.net> > Cc: Cornelia Huck <cornelia.huck@de.ibm.com> > Cc: Christian Borntraeger <borntraeger@de.ibm.com> > Cc: Paolo Bonzini <pbonzini@redhat.com> > Signed-off-by: Jason Wang <jasowang@redhat.com> > --- > hw/net/virtio-net.c | 4 ++-- > hw/s390x/s390-virtio-bus.c | 1 + > hw/s390x/virtio-ccw.c | 1 + > hw/scsi/virtio-scsi.c | 4 ++-- > hw/virtio/virtio-mmio.c | 1 + > hw/virtio/virtio-pci.c | 1 + > hw/virtio/virtio.c | 52 +++++++++++++++++++++++++++++++----------- > include/hw/virtio/virtio-bus.h | 1 + > include/hw/virtio/virtio.h | 1 + > 9 files changed, 49 insertions(+), 17 deletions(-) > > diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > index ffc22e8..5a806b5 100644 > --- a/hw/virtio/virtio.c > +++ b/hw/virtio/virtio.c > @@ -541,6 +541,14 @@ void virtio_update_irq(VirtIODevice *vdev) > virtio_notify_vector(vdev, VIRTIO_NO_VECTOR); > } > > +int virtio_get_queue_max(VirtIODevice *vdev) > +{ > + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); > + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); > + > + return k->queue_max; > +} > + Are all callers of this in the slow path? So we don't introduce processing overhead. > void virtio_set_status(VirtIODevice *vdev, uint8_t val) > { > VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); (...) > @@ -777,27 +790,35 @@ void virtio_queue_notify(VirtIODevice *vdev, int n) > > uint16_t virtio_queue_vector(VirtIODevice *vdev, int n) > { > - return n < VIRTIO_PCI_QUEUE_MAX ? vdev->vq[n].vector : > + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); > + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); > + > + return n < k->queue_max ? vdev->vq[n].vector : Any reason you're not using the newly introduced virtio_get_queue_max()? > VIRTIO_NO_VECTOR; > } Do we need to care about migration if the target supports a different number of queues? I'm also not sure whether it would be sufficient to allow transports to limit queues to a lower number than the core supports. We'd basically only need to block off queue creation in the individual transports, I think.
On Thu, Feb 26, 2015 at 6:19 PM, Michael S. Tsirkin <mst@redhat.com> wrote: > On Thu, Feb 26, 2015 at 03:04:38PM +0800, Jason Wang wrote: >> This patch introduces a bus specific queue limitation. It will be >> useful for increasing the limit for one of the bus without >> disturbing >> other buses. > > Is this about s390 only supporting up to 64 queues? Not specific to s390. It just introduces a queue_max to each bus and main changes were done for virito core. For each specific transport, it just set queue_max to VIRTIO_PCI_QUEUE_MAX(64).
On Thu, Feb 26, 2015 at 8:57 PM, Cornelia Huck <cornelia.huck@de.ibm.com> wrote: > On Thu, 26 Feb 2015 15:04:38 +0800 > Jason Wang <jasowang@redhat.com> wrote: > >> This patch introduces a bus specific queue limitation. It will be >> useful for increasing the limit for one of the bus without >> disturbing >> other buses. >> >> Cc: Anthony Liguori <aliguori@amazon.com> >> Cc: Michael S. Tsirkin <mst@redhat.com> >> Cc: Alexander Graf <agraf@suse.de> >> Cc: Richard Henderson <rth@twiddle.net> >> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> >> Cc: Christian Borntraeger <borntraeger@de.ibm.com> >> Cc: Paolo Bonzini <pbonzini@redhat.com> >> Signed-off-by: Jason Wang <jasowang@redhat.com> >> --- >> hw/net/virtio-net.c | 4 ++-- >> hw/s390x/s390-virtio-bus.c | 1 + >> hw/s390x/virtio-ccw.c | 1 + >> hw/scsi/virtio-scsi.c | 4 ++-- >> hw/virtio/virtio-mmio.c | 1 + >> hw/virtio/virtio-pci.c | 1 + >> hw/virtio/virtio.c | 52 >> +++++++++++++++++++++++++++++++----------- >> include/hw/virtio/virtio-bus.h | 1 + >> include/hw/virtio/virtio.h | 1 + >> 9 files changed, 49 insertions(+), 17 deletions(-) >> > >> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c >> index ffc22e8..5a806b5 100644 >> --- a/hw/virtio/virtio.c >> +++ b/hw/virtio/virtio.c >> @@ -541,6 +541,14 @@ void virtio_update_irq(VirtIODevice *vdev) >> virtio_notify_vector(vdev, VIRTIO_NO_VECTOR); >> } >> >> +int virtio_get_queue_max(VirtIODevice *vdev) >> +{ >> + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); >> + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); >> + >> + return k->queue_max; >> +} >> + > > Are all callers of this in the slow path? So we don't introduce > processing overhead. Looks not. For overhead, do you mean one introduced by VIRTIO_BUS_GET_CLASS()? Not sure how much it will affact but we've already used something like this in the datapath, e.g virtio_notify_vector(). > > >> void virtio_set_status(VirtIODevice *vdev, uint8_t val) >> { >> VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); > > (...) > > >> @@ -777,27 +790,35 @@ void virtio_queue_notify(VirtIODevice *vdev, >> int n) >> >> uint16_t virtio_queue_vector(VirtIODevice *vdev, int n) >> { >> - return n < VIRTIO_PCI_QUEUE_MAX ? vdev->vq[n].vector : >> + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); >> + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); >> + >> + return n < k->queue_max ? vdev->vq[n].vector : > > Any reason you're not using the newly introduced > virtio_get_queue_max()? Yes, better use virtio_get_queue_max(). > > >> VIRTIO_NO_VECTOR; >> } > > Do we need to care about migration if the target supports a different > number of queues? See patch 9, if a target support a different number of queues, it can patch the k->queue_max during its initialization. > > > I'm also not sure whether it would be sufficient to allow transports > to > limit queues to a lower number than the core supports. We'd basically > only need to block off queue creation in the individual transports, I > think. Not sure I understand the issue correctly, with this series. There's not core limitation but only transport limitation.
On Fri, 27 Feb 2015 03:42:00 +0008 Jason Wang <jasowang@redhat.com> wrote: > On Thu, Feb 26, 2015 at 8:57 PM, Cornelia Huck > <cornelia.huck@de.ibm.com> wrote: > > On Thu, 26 Feb 2015 15:04:38 +0800 > > Jason Wang <jasowang@redhat.com> wrote: > > > >> This patch introduces a bus specific queue limitation. It will be > >> useful for increasing the limit for one of the bus without > >> disturbing > >> other buses. > >> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > >> index ffc22e8..5a806b5 100644 > >> --- a/hw/virtio/virtio.c > >> +++ b/hw/virtio/virtio.c > >> @@ -541,6 +541,14 @@ void virtio_update_irq(VirtIODevice *vdev) > >> virtio_notify_vector(vdev, VIRTIO_NO_VECTOR); > >> } > >> > >> +int virtio_get_queue_max(VirtIODevice *vdev) > >> +{ > >> + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); > >> + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); > >> + > >> + return k->queue_max; > >> +} > >> + > > > > Are all callers of this in the slow path? So we don't introduce > > processing overhead. > > Looks not. For overhead, do you mean one introduced by > VIRTIO_BUS_GET_CLASS()? Not sure how much it will affact but we've > already used something like this in the datapath, e.g > virtio_notify_vector(). I may have misremembered how much overhead those types of operation introduce. But it made me think: This function is basically introducing a per-VirtIODevice queue limit. We set it once in the VirtioBusClass during initialization, but don't expect it to change. Why don't we just propagate it to a new member of VirtIODevice during initialization instead?
On Fri, Feb 27, 2015 at 5:34 PM, Cornelia Huck <cornelia.huck@de.ibm.com> wrote: > On Fri, 27 Feb 2015 03:42:00 +0008 > Jason Wang <jasowang@redhat.com> wrote: > >> On Thu, Feb 26, 2015 at 8:57 PM, Cornelia Huck >> <cornelia.huck@de.ibm.com> wrote: >> > On Thu, 26 Feb 2015 15:04:38 +0800 >> > Jason Wang <jasowang@redhat.com> wrote: >> > >> >> This patch introduces a bus specific queue limitation. It will >> be >> >> useful for increasing the limit for one of the bus without >> >> disturbing >> >> other buses. > >> >> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c >> >> index ffc22e8..5a806b5 100644 >> >> --- a/hw/virtio/virtio.c >> >> +++ b/hw/virtio/virtio.c >> >> @@ -541,6 +541,14 @@ void virtio_update_irq(VirtIODevice *vdev) >> >> virtio_notify_vector(vdev, VIRTIO_NO_VECTOR); >> >> } >> >> >> >> +int virtio_get_queue_max(VirtIODevice *vdev) >> >> +{ >> >> + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); >> >> + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); >> >> + >> >> + return k->queue_max; >> >> +} >> >> + >> > >> > Are all callers of this in the slow path? So we don't introduce >> > processing overhead. >> >> Looks not. For overhead, do you mean one introduced by >> VIRTIO_BUS_GET_CLASS()? Not sure how much it will affact but we've >> already used something like this in the datapath, e.g >> virtio_notify_vector(). > > I may have misremembered how much overhead those types of operation > introduce. > > But it made me think: This function is basically introducing a > per-VirtIODevice queue limit. We set it once in the VirtioBusClass > during initialization, but don't expect it to change. Why don't we > just > propagate it to a new member of VirtIODevice during initialization > instead? The limit may be changed. Consider that patch 9 increases the pci limit from 64 to 513. But we want to keep the migration compatibility for legacy machine types e.g machines earlier than pc-q35-2.3 or pc-i440fx-2.3, so the limit was changed back to 64 in pc_compat_2_2(). More work will be done if we want to propagate it to VirtIODevice, and it looks unnecessary.
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c index c8d2cca..260345c 100644 --- a/hw/net/virtio-net.c +++ b/hw/net/virtio-net.c @@ -1585,10 +1585,10 @@ static void virtio_net_device_realize(DeviceState *dev, Error **errp) virtio_init(vdev, "virtio-net", VIRTIO_ID_NET, n->config_size); n->max_queues = MAX(n->nic_conf.peers.queues, 1); - if (n->max_queues * 2 + 1 > VIRTIO_PCI_QUEUE_MAX) { + if (n->max_queues * 2 + 1 > virtio_get_queue_max(vdev)) { error_setg(errp, "Invalid number of queues (= %" PRIu32 "), " "must be a postive integer less than %d.", - n->max_queues, (VIRTIO_PCI_QUEUE_MAX - 1) / 2); + n->max_queues, (virtio_get_queue_max(vdev) - 1) / 2); virtio_cleanup(vdev); return; } diff --git a/hw/s390x/s390-virtio-bus.c b/hw/s390x/s390-virtio-bus.c index 39dc201..d48590a 100644 --- a/hw/s390x/s390-virtio-bus.c +++ b/hw/s390x/s390-virtio-bus.c @@ -707,6 +707,7 @@ static void virtio_s390_bus_class_init(ObjectClass *klass, void *data) bus_class->max_dev = 1; k->notify = virtio_s390_notify; k->get_features = virtio_s390_get_features; + k->queue_max = VIRTIO_PCI_QUEUE_MAX; } static const TypeInfo virtio_s390_bus_info = { diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c index ea236c9..4874622 100644 --- a/hw/s390x/virtio-ccw.c +++ b/hw/s390x/virtio-ccw.c @@ -1695,6 +1695,7 @@ static void virtio_ccw_bus_class_init(ObjectClass *klass, void *data) k->load_queue = virtio_ccw_load_queue; k->save_config = virtio_ccw_save_config; k->load_config = virtio_ccw_load_config; + k->queue_max = VIRTIO_PCI_QUEUE_MAX; } static const TypeInfo virtio_ccw_bus_info = { diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c index 9e2c718..91d49f1 100644 --- a/hw/scsi/virtio-scsi.c +++ b/hw/scsi/virtio-scsi.c @@ -822,10 +822,10 @@ void virtio_scsi_common_realize(DeviceState *dev, Error **errp, sizeof(VirtIOSCSIConfig)); if (s->conf.num_queues == 0 || - s->conf.num_queues > VIRTIO_PCI_QUEUE_MAX - 2) { + s->conf.num_queues > virtio_get_queue_max(vdev) - 2) { error_setg(errp, "Invalid number of queues (= %" PRIu32 "), " "must be a positive integer less than %d.", - s->conf.num_queues, VIRTIO_PCI_QUEUE_MAX - 2); + s->conf.num_queues, virtio_get_queue_max(vdev) - 2); virtio_cleanup(vdev); return; } diff --git a/hw/virtio/virtio-mmio.c b/hw/virtio/virtio-mmio.c index 2450c13..ad03218 100644 --- a/hw/virtio/virtio-mmio.c +++ b/hw/virtio/virtio-mmio.c @@ -403,6 +403,7 @@ static void virtio_mmio_bus_class_init(ObjectClass *klass, void *data) k->device_plugged = virtio_mmio_device_plugged; k->has_variable_vring_alignment = true; bus_class->max_dev = 1; + k->queue_max = VIRTIO_PCI_QUEUE_MAX; } static const TypeInfo virtio_mmio_bus_info = { diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index dde1d73..7fa8141 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -1559,6 +1559,7 @@ static void virtio_pci_bus_class_init(ObjectClass *klass, void *data) k->vmstate_change = virtio_pci_vmstate_change; k->device_plugged = virtio_pci_device_plugged; k->device_unplugged = virtio_pci_device_unplugged; + k->queue_max = VIRTIO_PCI_QUEUE_MAX; } static const TypeInfo virtio_pci_bus_info = { diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index ffc22e8..5a806b5 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -541,6 +541,14 @@ void virtio_update_irq(VirtIODevice *vdev) virtio_notify_vector(vdev, VIRTIO_NO_VECTOR); } +int virtio_get_queue_max(VirtIODevice *vdev) +{ + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); + + return k->queue_max; +} + void virtio_set_status(VirtIODevice *vdev, uint8_t val) { VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); @@ -576,6 +584,8 @@ static enum virtio_device_endian virtio_current_cpu_endian(void) void virtio_reset(void *opaque) { VirtIODevice *vdev = opaque; + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); + VirtioBusClass *bk = VIRTIO_BUS_GET_CLASS(qbus); VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); int i; @@ -599,7 +609,7 @@ void virtio_reset(void *opaque) vdev->config_vector = VIRTIO_NO_VECTOR; virtio_notify_vector(vdev, vdev->config_vector); - for(i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) { + for(i = 0; i < bk->queue_max; i++) { vdev->vq[i].vring.desc = 0; vdev->vq[i].vring.avail = 0; vdev->vq[i].vring.used = 0; @@ -738,7 +748,10 @@ int virtio_queue_get_num(VirtIODevice *vdev, int n) int virtio_queue_get_id(VirtQueue *vq) { VirtIODevice *vdev = vq->vdev; - assert(vq >= &vdev->vq[0] && vq < &vdev->vq[VIRTIO_PCI_QUEUE_MAX]); + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); + + assert(vq >= &vdev->vq[0] && vq < &vdev->vq[k->queue_max]); return vq - &vdev->vq[0]; } @@ -777,27 +790,35 @@ void virtio_queue_notify(VirtIODevice *vdev, int n) uint16_t virtio_queue_vector(VirtIODevice *vdev, int n) { - return n < VIRTIO_PCI_QUEUE_MAX ? vdev->vq[n].vector : + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); + + return n < k->queue_max ? vdev->vq[n].vector : VIRTIO_NO_VECTOR; } void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector) { - if (n < VIRTIO_PCI_QUEUE_MAX) + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); + + if (n < k->queue_max) vdev->vq[n].vector = vector; } VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size, void (*handle_output)(VirtIODevice *, VirtQueue *)) { + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); int i; - for (i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) { + for (i = 0; i < k->queue_max; i++) { if (vdev->vq[i].vring.num == 0) break; } - if (i == VIRTIO_PCI_QUEUE_MAX || queue_size > VIRTQUEUE_MAX_SIZE) + if (i == k->queue_max || queue_size > VIRTQUEUE_MAX_SIZE) abort(); vdev->vq[i].vring.num = queue_size; @@ -809,7 +830,10 @@ VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size, void virtio_del_queue(VirtIODevice *vdev, int n) { - if (n < 0 || n >= VIRTIO_PCI_QUEUE_MAX) { + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); + + if (n < 0 || n >= k->queue_max) { abort(); } @@ -932,14 +956,14 @@ void virtio_save(VirtIODevice *vdev, QEMUFile *f) qemu_put_be32(f, vdev->config_len); qemu_put_buffer(f, vdev->config, vdev->config_len); - for (i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) { + for (i = 0; i < k->queue_max; i++) { if (vdev->vq[i].vring.num == 0) break; } qemu_put_be32(f, i); - for (i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) { + for (i = 0; i < k->queue_max; i++) { if (vdev->vq[i].vring.num == 0) break; @@ -1004,7 +1028,7 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id) qemu_get_8s(f, &vdev->status); qemu_get_8s(f, &vdev->isr); qemu_get_be16s(f, &vdev->queue_sel); - if (vdev->queue_sel >= VIRTIO_PCI_QUEUE_MAX) { + if (vdev->queue_sel >= k->queue_max) { return -1; } qemu_get_be32s(f, &features); @@ -1031,7 +1055,7 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id) num = qemu_get_be32(f); - if (num > VIRTIO_PCI_QUEUE_MAX) { + if (num > k->queue_max) { error_report("Invalid number of PCI queues: 0x%x", num); return -1; } @@ -1141,15 +1165,17 @@ void virtio_instance_init_common(Object *proxy_obj, void *data, void virtio_init(VirtIODevice *vdev, const char *name, uint16_t device_id, size_t config_size) { + BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); + VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); int i; vdev->device_id = device_id; vdev->status = 0; vdev->isr = 0; vdev->queue_sel = 0; vdev->config_vector = VIRTIO_NO_VECTOR; - vdev->vq = g_malloc0(sizeof(VirtQueue) * VIRTIO_PCI_QUEUE_MAX); + vdev->vq = g_malloc0(sizeof(VirtQueue) * k->queue_max); vdev->vm_running = runstate_is_running(); - for (i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) { + for (i = 0; i < k->queue_max; i++) { vdev->vq[i].vector = VIRTIO_NO_VECTOR; vdev->vq[i].vdev = vdev; vdev->vq[i].queue_index = i; diff --git a/include/hw/virtio/virtio-bus.h b/include/hw/virtio/virtio-bus.h index 0756545..979835c 100644 --- a/include/hw/virtio/virtio-bus.h +++ b/include/hw/virtio/virtio-bus.h @@ -68,6 +68,7 @@ typedef struct VirtioBusClass { * Note that changing this will break migration for this transport. */ bool has_variable_vring_alignment; + uint16_t queue_max; } VirtioBusClass; struct VirtioBusState { diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h index f24997d..9fe0d92 100644 --- a/include/hw/virtio/virtio.h +++ b/include/hw/virtio/virtio.h @@ -223,6 +223,7 @@ void virtio_queue_notify(VirtIODevice *vdev, int n); uint16_t virtio_queue_vector(VirtIODevice *vdev, int n); void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector); void virtio_set_status(VirtIODevice *vdev, uint8_t val); +int virtio_get_queue_max(VirtIODevice *vdev); void virtio_reset(void *opaque); void virtio_update_irq(VirtIODevice *vdev); int virtio_set_features(VirtIODevice *vdev, uint32_t val);
This patch introduces a bus specific queue limitation. It will be useful for increasing the limit for one of the bus without disturbing other buses. Cc: Anthony Liguori <aliguori@amazon.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Alexander Graf <agraf@suse.de> Cc: Richard Henderson <rth@twiddle.net> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> --- hw/net/virtio-net.c | 4 ++-- hw/s390x/s390-virtio-bus.c | 1 + hw/s390x/virtio-ccw.c | 1 + hw/scsi/virtio-scsi.c | 4 ++-- hw/virtio/virtio-mmio.c | 1 + hw/virtio/virtio-pci.c | 1 + hw/virtio/virtio.c | 52 +++++++++++++++++++++++++++++++----------- include/hw/virtio/virtio-bus.h | 1 + include/hw/virtio/virtio.h | 1 + 9 files changed, 49 insertions(+), 17 deletions(-)