Commit 830d70db authored by Ouyang Changchun's avatar Ouyang Changchun Committed by Michael S. Tsirkin
Browse files

vhost-user: add multi queue support 



Based on patch by Nikolay Nikolaev:
Vhost-user will implement the multi queue support in a similar way
to what vhost already has - a separate thread for each queue.
To enable the multi queue functionality - a new command line parameter
"queues" is introduced for the vhost-user netdev.

Signed-off-by: default avatarNikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Signed-off-by: default avatarChangchun Ouyang <changchun.ouyang@intel.com>
Reviewed-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent 019a3edb

docs/specs/vhost-user.txt

+5 −0
Original line number Diff line number Diff line
@@ -127,6 +127,11 @@ in the ancillary data: 
If Master is unable to send the full message or receives a wrong reply it will

close the connection. An optional reconnection mechanism can be implemented.



Multi queue support

-------------------

The protocol supports multiple queues by setting all index fields in the sent

messages to a properly calculated value.



Message types

-------------

hw/net/vhost_net.c

+2 −1
Original line number Diff line number Diff line
@@ -157,6 +157,7 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options) 


    net->dev.nvqs = 2;

    net->dev.vqs = net->vqs;

    net->dev.vq_index = net->nc->queue_index;



    r = vhost_dev_init(&net->dev, options->opaque,

                       options->backend_type, options->force);
@@ -267,7 +268,7 @@ static void vhost_net_stop_one(struct vhost_net *net, 
        for (file.index = 0; file.index < net->dev.nvqs; ++file.index) {

            const VhostOps *vhost_ops = net->dev.vhost_ops;

            int r = vhost_ops->vhost_call(&net->dev, VHOST_RESET_OWNER,

                                          NULL);

                                          &file);

            assert(r >= 0);

        }

    }

hw/virtio/vhost-user.c

+10 −1
Original line number Diff line number Diff line
@@ -210,7 +210,12 @@ static int vhost_user_call(struct vhost_dev *dev, unsigned long int request, 
        break;



    case VHOST_SET_OWNER:

        break;



    case VHOST_RESET_OWNER:

        memcpy(&msg.state, arg, sizeof(struct vhost_vring_state));

        msg.state.index += dev->vq_index;

        msg.size = sizeof(m.state);

        break;



    case VHOST_SET_MEM_TABLE:
@@ -253,17 +258,20 @@ static int vhost_user_call(struct vhost_dev *dev, unsigned long int request, 
    case VHOST_SET_VRING_NUM:

    case VHOST_SET_VRING_BASE:

        memcpy(&msg.state, arg, sizeof(struct vhost_vring_state));

        msg.state.index += dev->vq_index;

        msg.size = sizeof(m.state);

        break;



    case VHOST_GET_VRING_BASE:

        memcpy(&msg.state, arg, sizeof(struct vhost_vring_state));

        msg.state.index += dev->vq_index;

        msg.size = sizeof(m.state);

        need_reply = 1;

        break;



    case VHOST_SET_VRING_ADDR:

        memcpy(&msg.addr, arg, sizeof(struct vhost_vring_addr));

        msg.addr.index += dev->vq_index;

        msg.size = sizeof(m.addr);

        break;
@@ -271,7 +279,7 @@ static int vhost_user_call(struct vhost_dev *dev, unsigned long int request, 
    case VHOST_SET_VRING_CALL:

    case VHOST_SET_VRING_ERR:

        file = arg;

        msg.u64 = file->index & VHOST_USER_VRING_IDX_MASK;

        msg.u64 = (file->index + dev->vq_index) & VHOST_USER_VRING_IDX_MASK;

        msg.size = sizeof(m.u64);

        if (ioeventfd_enabled() && file->fd > 0) {

            fds[fd_num++] = file->fd;
@@ -313,6 +321,7 @@ static int vhost_user_call(struct vhost_dev *dev, unsigned long int request, 
                error_report("Received bad msg size.");

                return -1;

            }

            msg.state.index -= dev->vq_index;

            memcpy(arg, &msg.state, sizeof(struct vhost_vring_state));

            break;

        default:

net/vhost-user.c

+24 −13
Original line number Diff line number Diff line
@@ -121,35 +121,39 @@ static void net_vhost_user_event(void *opaque, int event) 
    case CHR_EVENT_OPENED:

        vhost_user_start(s);

        net_vhost_link_down(s, false);

        error_report("chardev \"%s\" went up", s->chr->label);

        error_report("chardev \"%s\" went up", s->nc.info_str);

        break;

    case CHR_EVENT_CLOSED:

        net_vhost_link_down(s, true);

        vhost_user_stop(s);

        error_report("chardev \"%s\" went down", s->chr->label);

        error_report("chardev \"%s\" went down", s->nc.info_str);

        break;

    }

}



static int net_vhost_user_init(NetClientState *peer, const char *device,

                               const char *name, CharDriverState *chr)

                               const char *name, CharDriverState *chr,

                               uint32_t queues)

{

    NetClientState *nc;

    VhostUserState *s;

    int i;



    for (i = 0; i < queues; i++) {

        nc = qemu_new_net_client(&net_vhost_user_info, peer, device, name);



    snprintf(nc->info_str, sizeof(nc->info_str), "vhost-user to %s",

             chr->label);

        snprintf(nc->info_str, sizeof(nc->info_str), "vhost-user%d to %s",

                 i, chr->label);



        s = DO_UPCAST(VhostUserState, nc, nc);



        /* We don't provide a receive callback */

        s->nc.receive_disabled = 1;

        s->chr = chr;

        s->nc.queue_index = i;



        qemu_chr_add_handlers(s->chr, NULL, NULL, net_vhost_user_event, s);



    }

    return 0;

}
@@ -226,6 +230,7 @@ int net_init_vhost_user(const NetClientOptions *opts, const char *name, 
                        NetClientState *peer, Error **errp)

{

    /* FIXME error_setg(errp, ...) on failure */

    uint32_t queues;

    const NetdevVhostUserOptions *vhost_user_opts;

    CharDriverState *chr;
@@ -244,6 +249,12 @@ int net_init_vhost_user(const NetClientOptions *opts, const char *name, 
        return -1;

    }



    /* number of queues for multiqueue */

    if (vhost_user_opts->has_queues) {

        queues = vhost_user_opts->queues;

    } else {

        queues = 1;

    }



    return net_vhost_user_init(peer, "vhost_user", name, chr);

    return net_vhost_user_init(peer, "vhost_user", name, chr, queues);

}

qapi-schema.json

+5 −1
Original line number Diff line number Diff line
@@ -2444,12 +2444,16 @@ 
#

# @vhostforce: #optional vhost on for non-MSIX virtio guests (default: false).

#

# @queues: #optional number of queues to be created for multiqueue vhost-user

#          (default: 1) (Since 2.4)

#

# Since 2.1

##

{ 'struct': 'NetdevVhostUserOptions',

  'data': {

    'chardev':        'str',

    '*vhostforce':    'bool' } }

    '*vhostforce':    'bool',

    '*queues':        'uint32' } }



##

# @NetClientOptions