[PATCH net-next 1/2] net: introduce UDP GRO netdev feature

From: Alexander Lobakin
Date: Mon Jan 18 2021 - 14:42:59 EST


Introduce a new netdev_feature, NETIF_F_GRO_UDP, to allow user
to turn UDP GRO on and off when there is no socket, e.g. when
forwarding.
Defaults to off to not change current datapath.

Suggested-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: Alexander Lobakin <alobakin@xxxxx>
---
include/linux/netdev_features.h | 4 +++-
net/ethtool/common.c | 1 +
2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h
index 934de56644e7..c6526aa13684 100644
--- a/include/linux/netdev_features.h
+++ b/include/linux/netdev_features.h
@@ -84,6 +84,7 @@ enum {
NETIF_F_GRO_FRAGLIST_BIT, /* Fraglist GRO */

NETIF_F_HW_MACSEC_BIT, /* Offload MACsec operations */
+ NETIF_F_GRO_UDP_BIT, /* Enable UDP GRO */

/*
* Add your fresh new feature above and remember to update
@@ -157,6 +158,7 @@ enum {
#define NETIF_F_GRO_FRAGLIST __NETIF_F(GRO_FRAGLIST)
#define NETIF_F_GSO_FRAGLIST __NETIF_F(GSO_FRAGLIST)
#define NETIF_F_HW_MACSEC __NETIF_F(HW_MACSEC)
+#define NETIF_F_GRO_UDP __NETIF_F(GRO_UDP)

/* Finds the next feature with the highest number of the range of start till 0.
*/
@@ -234,7 +236,7 @@ static inline int find_next_netdev_feature(u64 feature, unsigned long start)
#define NETIF_F_SOFT_FEATURES (NETIF_F_GSO | NETIF_F_GRO)

/* Changeable features with no special hardware requirements that defaults to off. */
-#define NETIF_F_SOFT_FEATURES_OFF NETIF_F_GRO_FRAGLIST
+#define NETIF_F_SOFT_FEATURES_OFF (NETIF_F_GRO_FRAGLIST | NETIF_F_GRO_UDP)

#define NETIF_F_VLAN_FEATURES (NETIF_F_HW_VLAN_CTAG_FILTER | \
NETIF_F_HW_VLAN_CTAG_RX | \
diff --git a/net/ethtool/common.c b/net/ethtool/common.c
index 24036e3055a1..e45128882372 100644
--- a/net/ethtool/common.c
+++ b/net/ethtool/common.c
@@ -68,6 +68,7 @@ const char netdev_features_strings[NETDEV_FEATURE_COUNT][ETH_GSTRING_LEN] = {
[NETIF_F_HW_TLS_RX_BIT] = "tls-hw-rx-offload",
[NETIF_F_GRO_FRAGLIST_BIT] = "rx-gro-list",
[NETIF_F_HW_MACSEC_BIT] = "macsec-hw-offload",
+ [NETIF_F_GRO_UDP_BIT] = "rx-gro-udp",
};

const char
--
2.30.0