From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47155) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZHA6X-0007X4-Mt for qemu-devel@nongnu.org; Mon, 20 Jul 2015 08:23:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZHA6T-0001BF-17 for qemu-devel@nongnu.org; Mon, 20 Jul 2015 08:23:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:53823) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZHA6S-0001BB-QL for qemu-devel@nongnu.org; Mon, 20 Jul 2015 08:23:28 -0400 Date: Mon, 20 Jul 2015 15:12:26 +0300 From: "Michael S. Tsirkin" Message-ID: <1437394279-24416-7-git-send-email-mst@redhat.com> References: <1437394279-24416-1-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1437394279-24416-1-git-send-email-mst@redhat.com> Subject: [Qemu-devel] [PULL 6/6] virtio-net: remove virtio queues if the guest doesn't support multiqueue List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Peter Maydell , Jason Wang From: Wen Congyang commit da51a335 adds all queues in .realize(). But if the guest doesn't support multiqueue, we forget to remove them. And we cannot handle the ctrl vq corretly. The guest will hang. Signed-off-by: Wen Congyang Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin Acked-by: Jason Wang --- hw/net/virtio-net.c | 110 +++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 82 insertions(+), 28 deletions(-) diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c index e1d9cbf..304d3dd 100644 --- a/hw/net/virtio-net.c +++ b/hw/net/virtio-net.c @@ -1327,9 +1327,86 @@ static void virtio_net_tx_bh(void *opaque) } } +static void virtio_net_add_queue(VirtIONet *n, int index) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(n); + + n->vqs[index].rx_vq = virtio_add_queue(vdev, 256, virtio_net_handle_rx); + if (n->net_conf.tx && !strcmp(n->net_conf.tx, "timer")) { + n->vqs[index].tx_vq = + virtio_add_queue(vdev, 256, virtio_net_handle_tx_timer); + n->vqs[index].tx_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, + virtio_net_tx_timer, + &n->vqs[index]); + } else { + n->vqs[index].tx_vq = + virtio_add_queue(vdev, 256, virtio_net_handle_tx_bh); + n->vqs[index].tx_bh = qemu_bh_new(virtio_net_tx_bh, &n->vqs[index]); + } + + n->vqs[index].tx_waiting = 0; + n->vqs[index].n = n; +} + +static void virtio_net_del_queue(VirtIONet *n, int index) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(n); + VirtIONetQueue *q = &n->vqs[index]; + NetClientState *nc = qemu_get_subqueue(n->nic, index); + + qemu_purge_queued_packets(nc); + + virtio_del_queue(vdev, index * 2); + if (q->tx_timer) { + timer_del(q->tx_timer); + timer_free(q->tx_timer); + } else { + qemu_bh_delete(q->tx_bh); + } + virtio_del_queue(vdev, index * 2 + 1); +} + +static void virtio_net_change_num_queues(VirtIONet *n, int new_max_queues) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(n); + int old_num_queues = virtio_get_num_queues(vdev); + int new_num_queues = new_max_queues * 2 + 1; + int i; + + assert(old_num_queues >= 3); + assert(old_num_queues % 2 == 1); + + if (old_num_queues == new_num_queues) { + return; + } + + /* + * We always need to remove and add ctrl vq if + * old_num_queues != new_num_queues. Remove ctrl_vq first, + * and then we only enter one of the following too loops. + */ + virtio_del_queue(vdev, old_num_queues - 1); + + for (i = new_num_queues - 1; i < old_num_queues - 1; i += 2) { + /* new_num_queues < old_num_queues */ + virtio_net_del_queue(n, i / 2); + } + + for (i = old_num_queues - 1; i < new_num_queues - 1; i += 2) { + /* new_num_queues > old_num_queues */ + virtio_net_add_queue(n, i / 2); + } + + /* add ctrl_vq last */ + n->ctrl_vq = virtio_add_queue(vdev, 64, virtio_net_handle_ctrl); +} + static void virtio_net_set_multiqueue(VirtIONet *n, int multiqueue) { + int max = multiqueue ? n->max_queues : 1; + n->multiqueue = multiqueue; + virtio_net_change_num_queues(n, max); virtio_net_set_queues(n); } @@ -1604,21 +1681,7 @@ static void virtio_net_device_realize(DeviceState *dev, Error **errp) } for (i = 0; i < n->max_queues; i++) { - n->vqs[i].rx_vq = virtio_add_queue(vdev, 256, virtio_net_handle_rx); - if (n->net_conf.tx && !strcmp(n->net_conf.tx, "timer")) { - n->vqs[i].tx_vq = - virtio_add_queue(vdev, 256, virtio_net_handle_tx_timer); - n->vqs[i].tx_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, - virtio_net_tx_timer, - &n->vqs[i]); - } else { - n->vqs[i].tx_vq = - virtio_add_queue(vdev, 256, virtio_net_handle_tx_bh); - n->vqs[i].tx_bh = qemu_bh_new(virtio_net_tx_bh, &n->vqs[i]); - } - - n->vqs[i].tx_waiting = 0; - n->vqs[i].n = n; + virtio_net_add_queue(n, i); } n->ctrl_vq = virtio_add_queue(vdev, 64, virtio_net_handle_ctrl); @@ -1672,7 +1735,7 @@ static void virtio_net_device_unrealize(DeviceState *dev, Error **errp) { VirtIODevice *vdev = VIRTIO_DEVICE(dev); VirtIONet *n = VIRTIO_NET(dev); - int i; + int i, max_queues; /* This will stop vhost backend if appropriate. */ virtio_net_set_status(vdev, 0); @@ -1687,18 +1750,9 @@ static void virtio_net_device_unrealize(DeviceState *dev, Error **errp) g_free(n->mac_table.macs); g_free(n->vlans); - for (i = 0; i < n->max_queues; i++) { - VirtIONetQueue *q = &n->vqs[i]; - NetClientState *nc = qemu_get_subqueue(n->nic, i); - - qemu_purge_queued_packets(nc); - - if (q->tx_timer) { - timer_del(q->tx_timer); - timer_free(q->tx_timer); - } else if (q->tx_bh) { - qemu_bh_delete(q->tx_bh); - } + max_queues = n->multiqueue ? n->max_queues : 1; + for (i = 0; i < max_queues; i++) { + virtio_net_del_queue(n, i); } timer_del(n->announce_timer); -- MST