diff mbox series

igc: fix tunnel offloading

Message ID 20210817131620.566614-1-vinschen@redhat.com
State Accepted
Delegated to: Anthony Nguyen
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'

=== 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(-)

Comments

Sasha Neftin Aug. 23, 2021, 5:46 a.m. UTC | #1
On 8/17/2021 16:42, Sasha Neftin wrote:
> 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(-)
>>
>> 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;
>Acked-by: Sasha Neftin <sasha.neftin@intel.com>
Kraus, NechamaX Sept. 14, 2021, 10:42 a.m. UTC | #2
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

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;