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| author | Eric Dumazet <edumazet@google.com> | 2014-10-05 10:11:27 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-10-06 17:56:28 -0400 |
| commit | fcbeb976d7ce783fd58e63e61c196d9a8912b3be (patch) | |
| tree | c6dde6923e5316b2bfc4bdb04bd6643515cc1598 | |
| parent | 9d31a7b9f9963e97e067e72ef13492e6ace7d345 (diff) | |
| download | linux-fcbeb976d7ce783fd58e63e61c196d9a8912b3be.tar.gz linux-fcbeb976d7ce783fd58e63e61c196d9a8912b3be.tar.bz2 linux-fcbeb976d7ce783fd58e63e61c196d9a8912b3be.zip | |
net: introduce netdevice gso_min_segs attribute
Some TSO engines might have a too heavy setup cost, that impacts
performance on hosts sending small bursts (2 MSS per packet).
This patch adds a device gso_min_segs, allowing drivers to set
a minimum segment size for TSO packets, according to the NIC
performance.
Tested on a mlx4 NIC, this allows to get a ~110% increase of
throughput when sending 2 MSS per packet.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/linux/netdevice.h | 4 | ||||
| -rw-r--r-- | net/core/dev.c | 9 |
2 files changed, 9 insertions, 4 deletions
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 22d54b9b700d..2df86f50261c 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1416,6 +1416,8 @@ enum netdev_priv_flags { * @gso_max_size: Maximum size of generic segmentation offload * @gso_max_segs: Maximum number of segments that can be passed to the * NIC for GSO + * @gso_min_segs: Minimum number of segments that can be passed to the + * NIC for GSO * * @dcbnl_ops: Data Center Bridging netlink ops * @num_tc: Number of traffic classes in the net device @@ -1666,7 +1668,7 @@ struct net_device { unsigned int gso_max_size; #define GSO_MAX_SEGS 65535 u16 gso_max_segs; - + u16 gso_min_segs; #ifdef CONFIG_DCB const struct dcbnl_rtnl_ops *dcbnl_ops; #endif diff --git a/net/core/dev.c b/net/core/dev.c index 7d5691cc1f47..c1a4de275576 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2567,10 +2567,12 @@ static netdev_features_t harmonize_features(struct sk_buff *skb, netdev_features_t netif_skb_features(struct sk_buff *skb) { + const struct net_device *dev = skb->dev; + netdev_features_t features = dev->features; + u16 gso_segs = skb_shinfo(skb)->gso_segs; __be16 protocol = skb->protocol; - netdev_features_t features = skb->dev->features; - if (skb_shinfo(skb)->gso_segs > skb->dev->gso_max_segs) + if (gso_segs > dev->gso_max_segs || gso_segs < dev->gso_min_segs) features &= ~NETIF_F_GSO_MASK; if (protocol == htons(ETH_P_8021Q) || protocol == htons(ETH_P_8021AD)) { @@ -2581,7 +2583,7 @@ netdev_features_t netif_skb_features(struct sk_buff *skb) } features = netdev_intersect_features(features, - skb->dev->vlan_features | + dev->vlan_features | NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX); @@ -6661,6 +6663,7 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, dev->gso_max_size = GSO_MAX_SIZE; dev->gso_max_segs = GSO_MAX_SEGS; + dev->gso_min_segs = 0; INIT_LIST_HEAD(&dev->napi_list); INIT_LIST_HEAD(&dev->unreg_list); |