diff mbox series

igc: fix tunnel offloading

Message ID 20210817131620.566614-1-vinschen@redhat.com
State New
Headers show
Series igc: fix tunnel offloading | expand

Commit Message

Corinna Vinschen Aug. 17, 2021, 1:16 p.m. UTC
From: Paolo Abeni <pabeni@redhat.com>

Checking tunnel offloading, it turns out that offloading doesn't work
as expected.  The following script allows to reproduce the issue.
Call it as `testscript DEVICE LOCALIP REMOTEIP NETMASK'

Comments

Kraus, NechamaX Sept. 14, 2021, 10:42 a.m. UTC | #1
On 8/17/2021 16:16, Corinna Vinschen wrote:
> From: Paolo Abeni <pabeni@redhat.com>

> 

> Checking tunnel offloading, it turns out that offloading doesn't work

> as expected.  The following script allows to reproduce the issue.

> Call it as `testscript DEVICE LOCALIP REMOTEIP NETMASK'

> 

> === SNIP ===

> if [ $# -ne 4 ]

> then

>    echo "Usage $0 DEVICE LOCALIP REMOTEIP NETMASK"

>    exit 1

> fi

> DEVICE="$1"

> LOCAL_ADDRESS="$2"

> REMOTE_ADDRESS="$3"

> NWMASK="$4"

> echo "Driver: $(ethtool -i ${DEVICE} | awk '/^driver:/{print $2}') "

> ethtool -k "${DEVICE}" | grep tx-udp

> echo

> echo "Set up NIC and tunnel..."

> ip addr add "${LOCAL_ADDRESS}/${NWMASK}" dev "${DEVICE}"

> ip link set "${DEVICE}" up

> sleep 2

> ip link add vxlan1 type vxlan id 42 \

> 		   remote "${REMOTE_ADDRESS}" \

> 		   local "${LOCAL_ADDRESS}" \

> 		   dstport 0 \

> 		   dev "${DEVICE}"

> ip addr add fc00::1/64 dev vxlan1

> ip link set vxlan1 up

> sleep 2

> rm -f vxlan.pcap

> echo "Running tcpdump and iperf3..."

> ( nohup tcpdump -i any -w vxlan.pcap >/dev/null 2>&1 ) &

> sleep 2

> iperf3 -c fc00::2 >/dev/null

> pkill tcpdump

> echo

> echo -n "Max. Paket Size: "

> tcpdump -r vxlan.pcap -nnle 2>/dev/null \

> | grep "${LOCAL_ADDRESS}.*> ${REMOTE_ADDRESS}.*OTV" \

> | awk '{print $8}' | awk -F ':' '{print $1}' \

> | sort -n | tail -1

> echo

> ip link del vxlan1

> ip addr del ${LOCAL_ADDRESS}/${NWMASK} dev "${DEVICE}"

> === SNAP ===

> 

> The expected outcome is

> 

>    Max. Paket Size: 64904

> 

> This is what you see on igb, the code igc has been taken from.

> However, on igc the output is

> 

>    Max. Paket Size: 1516

> 

> so the GSO aggregate packets are segmented by the kernel before calling

> igc_xmit_frame.  Inside the subsequent call to igc_tso, the check for

> skb_is_gso(skb) fails and the function returns prematurely.

> 

> It turns out that this occurs because the feature flags aren't set

> entirely correctly in igc_probe.  In contrast to the original code

> from igb_probe, igc_probe neglects to set the flags required to allow

> tunnel offloading.

> 

> Setting the same flags as igb fixes the issue on igc.

> 

> Signed-off-by: Paolo Abeni <pabeni@redhat.com>

> Tested-by: Corinna Vinschen <vinschen@redhat.com>

> ---

>   drivers/net/ethernet/intel/igc/igc_main.c | 4 +++-

>   1 file changed, 3 insertions(+), 1 deletion(-)

> 

Tested-by: Nechama Kraus <nechamax.kraus@linux.intel.com>
diff mbox series

Patch

=== SNIP ===
if [ $# -ne 4 ]
then
  echo "Usage $0 DEVICE LOCALIP REMOTEIP NETMASK"
  exit 1
fi
DEVICE="$1"
LOCAL_ADDRESS="$2"
REMOTE_ADDRESS="$3"
NWMASK="$4"
echo "Driver: $(ethtool -i ${DEVICE} | awk '/^driver:/{print $2}') "
ethtool -k "${DEVICE}" | grep tx-udp
echo
echo "Set up NIC and tunnel..."
ip addr add "${LOCAL_ADDRESS}/${NWMASK}" dev "${DEVICE}"
ip link set "${DEVICE}" up
sleep 2
ip link add vxlan1 type vxlan id 42 \
		   remote "${REMOTE_ADDRESS}" \
		   local "${LOCAL_ADDRESS}" \
		   dstport 0 \
		   dev "${DEVICE}"
ip addr add fc00::1/64 dev vxlan1
ip link set vxlan1 up
sleep 2
rm -f vxlan.pcap
echo "Running tcpdump and iperf3..."
( nohup tcpdump -i any -w vxlan.pcap >/dev/null 2>&1 ) &
sleep 2
iperf3 -c fc00::2 >/dev/null
pkill tcpdump
echo
echo -n "Max. Paket Size: "
tcpdump -r vxlan.pcap -nnle 2>/dev/null \
| grep "${LOCAL_ADDRESS}.*> ${REMOTE_ADDRESS}.*OTV" \
| awk '{print $8}' | awk -F ':' '{print $1}' \
| sort -n | tail -1
echo
ip link del vxlan1
ip addr del ${LOCAL_ADDRESS}/${NWMASK} dev "${DEVICE}"
=== SNAP ===

The expected outcome is

  Max. Paket Size: 64904

This is what you see on igb, the code igc has been taken from.
However, on igc the output is

  Max. Paket Size: 1516

so the GSO aggregate packets are segmented by the kernel before calling
igc_xmit_frame.  Inside the subsequent call to igc_tso, the check for
skb_is_gso(skb) fails and the function returns prematurely.

It turns out that this occurs because the feature flags aren't set
entirely correctly in igc_probe.  In contrast to the original code
from igb_probe, igc_probe neglects to set the flags required to allow
tunnel offloading.

Setting the same flags as igb fixes the issue on igc.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Tested-by: Corinna Vinschen <vinschen@redhat.com>
---
 drivers/net/ethernet/intel/igc/igc_main.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index b7aab35c1132..79efb3e6a03e 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -6264,7 +6264,9 @@  static int igc_probe(struct pci_dev *pdev,
 	if (pci_using_dac)
 		netdev->features |= NETIF_F_HIGHDMA;
 
-	netdev->vlan_features |= netdev->features;
+	netdev->vlan_features |= netdev->features | NETIF_F_TSO_MANGLEID;
+	netdev->mpls_features |= NETIF_F_HW_CSUM;
+	netdev->hw_enc_features |= netdev->vlan_features;
 
 	/* MTU range: 68 - 9216 */
 	netdev->min_mtu = ETH_MIN_MTU;