[PATCH v4 07/25] virtio_net: drop config_enable

Michael S. Tsirkin
2014-10-13T07:50:18Z

Now that virtio core ensures config changes don't arrive during probing,
drop config_enable flag in virtio net.
On removal, flush is now sufficient to guarantee that no change work is
queued.

This help simplify the driver, and will allow setting DRIVER_OK earlier
without losing config change notifications.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
---
drivers/net/virtio_net.c | 27 ++++-----------------------
1 file changed, 4 insertions(+), 23 deletions(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 59caa06..743fb04 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -123,9 +123,6 @@ struct virtnet_info {
/* Host can handle any s/g split between our header and packet data */
bool any_header_sg;

- /* enable config space updates */
- bool config_enable;
-
/* Active statistics */
struct virtnet_stats __percpu *stats;

@@ -1408,9 +1405,6 @@ static void virtnet_config_changed_work(struct work_struct *work)
u16 v;

mutex_lock(&vi->config_lock);
- if (!vi->config_enable)
- goto done;
-
if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
struct virtio_net_config, status, &v) < 0)
goto done;
@@ -1758,7 +1752,6 @@ static int virtnet_probe(struct virtio_device *vdev)
}

mutex_init(&vi->config_lock);
- vi->config_enable = true;
INIT_WORK(&vi->config_work, virtnet_config_changed_work);

/* If we can receive ANY GSO packets, we must allocate large ones. */
@@ -1875,17 +1868,13 @@ static void virtnet_remove(struct virtio_device *vdev)

unregister_hotcpu_notifier(&vi->nb);

- /* Prevent config work handler from accessing the device. */
- mutex_lock(&vi->config_lock);
- vi->config_enable = false;
- mutex_unlock(&vi->config_lock);
+ /* Make sure no work handler is accessing the device. */
+ flush_work(&vi->config_work);

unregister_netdev(vi->dev);

remove_vq_common(vi);

- flush_work(&vi->config_work);
-
free_percpu(vi->stats);
free_netdev(vi->dev);
}
@@ -1898,10 +1887,8 @@ static int virtnet_freeze(struct virtio_device *vdev)

unregister_hotcpu_notifier(&vi->nb);

- /* Prevent config work handler from accessing the device */
- mutex_lock(&vi->config_lock);
- vi->config_enable = false;
- mutex_unlock(&vi->config_lock);
+ /* Make sure no work handler is accessing the device */
+ flush_work(&vi->config_work);

netif_device_detach(vi->dev);
cancel_delayed_work_sync(&vi->refill);
@@ -1916,8 +1903,6 @@ static int virtnet_freeze(struct virtio_device *vdev)

remove_vq_common(vi);

- flush_work(&vi->config_work);
-
return 0;
}

@@ -1941,10 +1926,6 @@ static int virtnet_restore(struct virtio_device *vdev)

netif_device_attach(vi->dev);

- mutex_lock(&vi->config_lock);
- vi->config_enable = true;
- mutex_unlock(&vi->config_lock);
-
rtnl_lock();
virtnet_set_queues(vi, vi->curr_queue_pairs);
rtnl_unlock();
--
MST