Implement ethtool .set_coalesce (-C) and .get_coalesce (-c) handlers. Interrupt moderation is currently not supported, so these accept and display the default settings of 0 usec and 1 frame. Toggle tx napi through setting tx-frames. So as to not interfere with possible future interrupt moderation, value 1 means tx napi while value 0 means not. Only allow the switching when device is down for simplicity. Link: https://patchwork.ozlabs.org/patch/948149/ Suggested-by: Jason Wang <jasowang@xxxxxxxxxx> Signed-off-by: Willem de Bruijn <willemb@xxxxxxxxxx> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx> --- Changes from V2: - only allow the switching when device is done - remove unnecessary global variable and initialization Changes from V1: - try to synchronize with datapath to allow changing mode when interface is up. - use tx-frames 0 as to disable tx napi while tx-frames 1 to enable tx napi --- drivers/net/virtio_net.c | 50 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 765920905226..751f385f4e0a 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -2181,6 +2181,54 @@ static int virtnet_get_link_ksettings(struct net_device *dev, return 0; } +static int virtnet_set_coalesce(struct net_device *dev, + struct ethtool_coalesce *ec) +{ + struct ethtool_coalesce ec_default = { + .cmd = ETHTOOL_SCOALESCE, + .rx_max_coalesced_frames = 1, + }; + struct virtnet_info *vi = netdev_priv(dev); + int i, napi_weight; + bool running = netif_running(dev); + + if (ec->tx_max_coalesced_frames > 1) + return -EINVAL; + + ec_default.tx_max_coalesced_frames = ec->tx_max_coalesced_frames; + napi_weight = ec->tx_max_coalesced_frames ? NAPI_POLL_WEIGHT : 0; + + /* disallow changes to fields not explicitly tested above */ + if (memcmp(ec, &ec_default, sizeof(ec_default))) + return -EINVAL; + + if (napi_weight ^ vi->sq[0].napi.weight) { + if (dev->flags & IFF_UP) + return -EBUSY; + for (i = 0; i < vi->max_queue_pairs; i++) + vi->sq[i].napi.weight = napi_weight; + } + + return 0; +} + +static int virtnet_get_coalesce(struct net_device *dev, + struct ethtool_coalesce *ec) +{ + struct ethtool_coalesce ec_default = { + .cmd = ETHTOOL_GCOALESCE, + .rx_max_coalesced_frames = 1, + }; + struct virtnet_info *vi = netdev_priv(dev); + + memcpy(ec, &ec_default, sizeof(ec_default)); + + if (vi->sq[0].napi.weight) + ec->tx_max_coalesced_frames = 1; + + return 0; +} + static void virtnet_init_settings(struct net_device *dev) { struct virtnet_info *vi = netdev_priv(dev); @@ -2219,6 +2267,8 @@ static const struct ethtool_ops virtnet_ethtool_ops = { .get_ts_info = ethtool_op_get_ts_info, .get_link_ksettings = virtnet_get_link_ksettings, .set_link_ksettings = virtnet_set_link_ksettings, + .set_coalesce = virtnet_set_coalesce, + .get_coalesce = virtnet_get_coalesce, }; static void virtnet_freeze_down(struct virtio_device *vdev) -- 2.17.1 _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
