Re: [PATCH 10/12] virtio-net: multiqueue support

[Jason Wang <jasowang@redhat.com>]

On 12/29/2012 01:52 AM, Blue Swirl wrote:
> On Fri, Dec 28, 2012 at 10:32 AM, Jason Wang <jasowang@redhat.com> wrote:
>> This patch implements both userspace and vhost support for multiple queue
>> virtio-net (VIRTIO_NET_F_MQ). This is done by introducing an array of
>> VirtIONetQueue to VirtIONet.
>>
>> Signed-off-by: Jason Wang <jasowang@redhat.com>
>> ---
>>  hw/virtio-net.c |  318 ++++++++++++++++++++++++++++++++++++++++++-------------
>>  hw/virtio-net.h |   27 +++++-
>>  2 files changed, 271 insertions(+), 74 deletions(-)
[...]
>>  static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
>>  {
>>      VirtIONet *n = to_virtio_net(vdev);
>> @@ -464,6 +578,8 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
>>              status = virtio_net_handle_mac(n, ctrl.cmd, &elem);
>>          else if (ctrl.class == VIRTIO_NET_CTRL_VLAN)
>>              status = virtio_net_handle_vlan_table(n, ctrl.cmd, &elem);
>> +        else if (ctrl.class == VIRTIO_NET_CTRL_MQ)
> Please add braces.

Sure.
>
>> +            status = virtio_net_handle_mq(n, ctrl.cmd, &elem);
>>
>>          stb_p(elem.in_sg[elem.in_num - 1].iov_base, status);
>>
>> @@ -477,19 +593,24 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
>>  static void virtio_net_handle_rx(VirtIODevice *vdev, VirtQueue *vq)
>>  {
>>      VirtIONet *n = to_virtio_net(vdev);
>> +    int queue_index = vq2q(virtio_get_queue_index(vq));
>>
>> -    qemu_flush_queued_packets(qemu_get_queue(n->nic));
>> +    qemu_flush_queued_packets(qemu_get_subqueue(n->nic, queue_index));
>>  }
>>
>>  
[...]
>>
>> +static void virtio_net_set_multiqueue(VirtIONet *n, int multiqueue, int ctrl)
>> +{
>> +    VirtIODevice *vdev = &n->vdev;
>> +    int i;
>> +
>> +    n->multiqueue = multiqueue;
>> +
>> +    if (!multiqueue)
>> +        n->curr_queues = 1;
> Ditto. Didn't checkpatch.pl catch these or did you not check?

Sorry, will add braces here. I run checkpatch.pl but finally find that
some or lots of the existed codes (such as this file) does not obey the
rules. So I'm not sure whether I need to correct my own codes, or left
them as this file does and correct them all in the future.
>
[...]
>>  } QEMU_PACKED;
>>
>>  /* This is the first element of the scatter-gather list.  If you don't
>> @@ -168,6 +172,26 @@ struct virtio_net_ctrl_mac {
>>   #define VIRTIO_NET_CTRL_VLAN_ADD             0
>>   #define VIRTIO_NET_CTRL_VLAN_DEL             1
>>
>> +/*
>> + * Control Multiqueue
>> + *
>> + * The command VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET
>> + * enables multiqueue, specifying the number of the transmit and
>> + * receive queues that will be used. After the command is consumed and acked by
>> + * the device, the device will not steer new packets on receive virtqueues
>> + * other than specified nor read from transmit virtqueues other than specified.
>> + * Accordingly, driver should not transmit new packets  on virtqueues other than
>> + * specified.
>> + */
>> +struct virtio_net_ctrl_mq {
> VirtIONetCtrlMQ and please don't forget the typedef.

Sure, but the same question as above. (See other structures in this file).
>
>> +    uint16_t virtqueue_pairs;
>> +};
>> +
>> +#define VIRTIO_NET_CTRL_MQ   4
>> + #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET        0
>> + #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN        1
>> + #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX        0x8000
>> +
>>  #define DEFINE_VIRTIO_NET_FEATURES(_state, _field) \
>>          DEFINE_VIRTIO_COMMON_FEATURES(_state, _field), \
>>          DEFINE_PROP_BIT("csum", _state, _field, VIRTIO_NET_F_CSUM, true), \
>> @@ -186,5 +210,6 @@ struct virtio_net_ctrl_mac {
>>          DEFINE_PROP_BIT("ctrl_vq", _state, _field, VIRTIO_NET_F_CTRL_VQ, true), \
>>          DEFINE_PROP_BIT("ctrl_rx", _state, _field, VIRTIO_NET_F_CTRL_RX, true), \
>>          DEFINE_PROP_BIT("ctrl_vlan", _state, _field, VIRTIO_NET_F_CTRL_VLAN, true), \
>> -        DEFINE_PROP_BIT("ctrl_rx_extra", _state, _field, VIRTIO_NET_F_CTRL_RX_EXTRA, true)
>> +        DEFINE_PROP_BIT("ctrl_rx_extra", _state, _field, VIRTIO_NET_F_CTRL_RX_EXTRA, true), \
>> +        DEFINE_PROP_BIT("mq", _state, _field, VIRTIO_NET_F_MQ, true)
>>  #endif
>> --
>> 1.7.1
>>
>>