From: Mark Kanda <mark.ka...@oracle.com> 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.ka...@oracle.com> Reviewed-by: Karl Heubaum <karl.heub...@oracle.com> Reviewed-by: Martin K. Petersen <martin.peter...@oracle.com> Reviewed-by: Ameya More <ameya.m...@oracle.com> Message-id: 52e6d742811f10dbd16e996e86cf375b9577c187.1513005190.git.mark.ka...@oracle.com Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com> --- include/hw/virtio/virtio-blk.h | 1 + hw/block/virtio-blk.c | 10 +++++++++- 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/include/hw/virtio/virtio-blk.h b/include/hw/virtio/virtio-blk.h index d3c8a6fa8c..5117431d96 100644 --- a/include/hw/virtio/virtio-blk.h +++ b/include/hw/virtio/virtio-blk.h @@ -39,6 +39,7 @@ struct VirtIOBlkConf uint32_t config_wce; uint32_t request_merging; uint16_t num_queues; + uint16_t queue_size; }; struct VirtIOBlockDataPlane; diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index ae3356f6a8..d8cfdc81f6 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -927,6 +927,13 @@ 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, @@ -949,7 +956,7 @@ 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); } if (!virtio_blk_data_plane_create(vdev, conf, &s->dataplane, errp)) { virtio_cleanup(vdev); @@ -1006,6 +1013,7 @@ 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(), -- 2.14.3