Commit 6040aedd authored by Mark Kanda's avatar Mark Kanda Committed by Stefan Hajnoczi
Browse files

virtio-blk: make queue size configurable 



Depending on the configuration, it can be beneficial to adjust the virtio-blk
queue size to something other than the current default of 128. Add a new
property to make the queue size configurable.

Signed-off-by: default avatarMark Kanda <mark.kanda@oracle.com>
Reviewed-by: default avatarKarl Heubaum <karl.heubaum@oracle.com>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: default avatarAmeya More <ameya.more@oracle.com>
Message-id: 52e6d742811f10dbd16e996e86cf375b9577c187.1513005190.git.mark.kanda@oracle.com
Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
parent 6dd64919

hw/block/virtio-blk.c

+9 −1
Original line number Diff line number Diff line
@@ -928,6 +928,13 @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp) 
        error_setg(errp, "num-queues property must be larger than 0");

        return;

    }

    if (!is_power_of_2(conf->queue_size) ||

        conf->queue_size > VIRTQUEUE_MAX_SIZE) {

        error_setg(errp, "invalid queue-size property (%" PRIu16 "), "

                   "must be a power of 2 (max %d)",

                   conf->queue_size, VIRTQUEUE_MAX_SIZE);

        return;

    }



    blkconf_serial(&conf->conf, &conf->serial);

    if (!blkconf_apply_backend_options(&conf->conf,
@@ -950,7 +957,7 @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp) 
    s->sector_mask = (s->conf.conf.logical_block_size / BDRV_SECTOR_SIZE) - 1;



    for (i = 0; i < conf->num_queues; i++) {

        virtio_add_queue(vdev, 128, virtio_blk_handle_output);

        virtio_add_queue(vdev, conf->queue_size, virtio_blk_handle_output);

    }

    virtio_blk_data_plane_create(vdev, conf, &s->dataplane, &err);

    if (err != NULL) {
@@ -1009,6 +1016,7 @@ static Property virtio_blk_properties[] = { 
    DEFINE_PROP_BIT("request-merging", VirtIOBlock, conf.request_merging, 0,

                    true),

    DEFINE_PROP_UINT16("num-queues", VirtIOBlock, conf.num_queues, 1),

    DEFINE_PROP_UINT16("queue-size", VirtIOBlock, conf.queue_size, 128),

    DEFINE_PROP_LINK("iothread", VirtIOBlock, conf.iothread, TYPE_IOTHREAD,

                     IOThread *),

    DEFINE_PROP_END_OF_LIST(),

include/hw/virtio/virtio-blk.h

+1 −0
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ struct VirtIOBlkConf 
    uint32_t config_wce;

    uint32_t request_merging;

    uint16_t num_queues;

    uint16_t queue_size;

};



struct VirtIOBlockDataPlane;