[PATCH RFC v5 net-next 4/6] virtio-net: add basic interrupt coalescing support
From: Jason Wang <jasowang@redhat.com>
Date: 2015-02-09 08:40:54
Also in:
lkml, netdev
Subsystem:
networking drivers, the rest, virtio core, virtio net driver · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, "Michael S. Tsirkin", Jason Wang
This patch enables the interrupt coalescing setting through ethtool. Cc: Rusty Russell <redacted> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> --- drivers/net/virtio_net.c | 67 +++++++++++++++++++++++++++++++++++++++++ include/uapi/linux/virtio_net.h | 12 ++++++++ 2 files changed, 79 insertions(+)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index cc5f5de..2b958fb 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c@@ -145,6 +145,11 @@ struct virtnet_info { /* Budget for polling tx completion */ u32 tx_work_limit; + + __u32 rx_coalesce_usecs; + __u32 rx_max_coalesced_frames; + __u32 tx_coalesce_usecs; + __u32 tx_max_coalesced_frames; }; struct padded_vnet_hdr {
@@ -1404,12 +1409,73 @@ static void virtnet_get_channels(struct net_device *dev, channels->other_count = 0; } +static int virtnet_set_coalesce(struct net_device *dev, + struct ethtool_coalesce *ec) +{ + struct virtnet_info *vi = netdev_priv(dev); + struct scatterlist sg; + struct virtio_net_ctrl_coalesce c; + + if (!vi->has_cvq || + !virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_COALESCE)) + return -EOPNOTSUPP; + if (vi->rx_coalesce_usecs != ec->rx_coalesce_usecs || + vi->rx_max_coalesced_frames != ec->rx_max_coalesced_frames) { + c.coalesce_usecs = ec->rx_coalesce_usecs; + c.max_coalesced_frames = ec->rx_max_coalesced_frames; + sg_init_one(&sg, &c, sizeof(c)); + if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_COALESCE, + VIRTIO_NET_CTRL_COALESCE_RX_SET, + &sg)) { + dev_warn(&dev->dev, "Fail to set rx coalescing\n"); + return -EINVAL; + } + vi->rx_coalesce_usecs = ec->rx_coalesce_usecs; + vi->rx_max_coalesced_frames = ec->rx_max_coalesced_frames; + } + + if (vi->tx_coalesce_usecs != ec->tx_coalesce_usecs || + vi->tx_max_coalesced_frames != ec->tx_max_coalesced_frames) { + c.coalesce_usecs = ec->tx_coalesce_usecs; + c.max_coalesced_frames = ec->tx_max_coalesced_frames; + sg_init_one(&sg, &c, sizeof(c)); + if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_COALESCE, + VIRTIO_NET_CTRL_COALESCE_TX_SET, + &sg)) { + dev_warn(&dev->dev, "Fail to set tx coalescing\n"); + return -EINVAL; + } + vi->tx_coalesce_usecs = ec->tx_coalesce_usecs; + vi->tx_max_coalesced_frames = ec->tx_max_coalesced_frames; + } + + vi->tx_work_limit = ec->tx_max_coalesced_frames_irq; + + return 0; +} + +static int virtnet_get_coalesce(struct net_device *dev, + struct ethtool_coalesce *ec) +{ + struct virtnet_info *vi = netdev_priv(dev); + + ec->rx_coalesce_usecs = vi->rx_coalesce_usecs; + ec->rx_max_coalesced_frames = vi->rx_max_coalesced_frames; + ec->tx_coalesce_usecs = vi->tx_coalesce_usecs; + ec->tx_max_coalesced_frames = vi->tx_max_coalesced_frames; + ec->tx_max_coalesced_frames_irq = vi->tx_work_limit; + + return 0; +} + static const struct ethtool_ops virtnet_ethtool_ops = { .get_drvinfo = virtnet_get_drvinfo, .get_link = ethtool_op_get_link, .get_ringparam = virtnet_get_ringparam, .set_channels = virtnet_set_channels, .get_channels = virtnet_get_channels, + .set_coalesce = virtnet_set_coalesce, + .get_coalesce = virtnet_get_coalesce, }; #define MIN_MTU 68
@@ -2048,6 +2114,7 @@ static unsigned int features[] = { VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, VIRTIO_NET_F_CTRL_MAC_ADDR, VIRTIO_F_ANY_LAYOUT, + VIRTIO_NET_F_CTRL_COALESCE, }; static struct virtio_driver virtio_net_driver = {
diff --git a/include/uapi/linux/virtio_net.h b/include/uapi/linux/virtio_net.h
index b5f1677..332009d 100644
--- a/include/uapi/linux/virtio_net.h
+++ b/include/uapi/linux/virtio_net.h@@ -34,6 +34,7 @@ /* The feature bitmap for virtio net */ #define VIRTIO_NET_F_CSUM 0 /* Host handles pkts w/ partial csum */ #define VIRTIO_NET_F_GUEST_CSUM 1 /* Guest handles pkts w/ partial csum */ +#define VIRTIO_NET_F_CTRL_COALESCE 3 /* Set coalescing */ #define VIRTIO_NET_F_MAC 5 /* Host has given MAC address. */ #define VIRTIO_NET_F_GSO 6 /* Host handles pkts w/ any GSO type */ #define VIRTIO_NET_F_GUEST_TSO4 7 /* Guest can handle TSOv4 in. */
@@ -202,4 +203,15 @@ struct virtio_net_ctrl_mq { #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN 1 #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX 0x8000 +struct virtio_net_ctrl_coalesce { + __u32 coalesce_usecs; + __u32 max_coalesced_frames; +}; + +#define VIRTIO_NET_CTRL_COALESCE 6 + #define VIRTIO_NET_CTRL_COALESCE_TX_SET 0 + #define VIRTIO_NET_CTRL_COALESCE_TX_GET 1 + #define VIRTIO_NET_CTRL_COALESCE_RX_SET 2 + #define VIRTIO_NET_CTRL_COALESCE_RX_GET 3 + #endif /* _LINUX_VIRTIO_NET_H */
--
1.8.3.1