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: Mark Kanda <mark.kanda@oracle.com>
Reviewed-by: Karl Heubaum <karl.heubaum@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Ameya More <ameya.more@oracle.com>
Message-id: 52e6d742811f10dbd16e996e86cf375b9577c187.1513005190.git.mark.kanda@oracle.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Mark Kanda 2017-12-11 09:16:24 -06:00 committed by Stefan Hajnoczi
parent 6dd64919ea
commit 6040aedddb
2 changed files with 10 additions and 1 deletions

View File

@ -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(),

View File

@ -39,6 +39,7 @@ struct VirtIOBlkConf
uint32_t config_wce;
uint32_t request_merging;
uint16_t num_queues;
uint16_t queue_size;
};
struct VirtIOBlockDataPlane;