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2016-09-19gso: Support partial splitting at the frag_list pointerSteffen Klassert
Since commit 8a29111c7 ("net: gro: allow to build full sized skb") gro may build buffers with a frag_list. This can hurt forwarding because most NICs can't offload such packets, they need to be segmented in software. This patch splits buffers with a frag_list at the frag_list pointer into buffers that can be TSO offloaded. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Acked-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-20gso: Remove arbitrary checks for unsupported GSOTom Herbert
In several gso_segment functions there are checks of gso_type against a seemingly arbitrary list of SKB_GSO_* flags. This seems like an attempt to identify unsupported GSO types, but since the stack is the one that set these GSO types in the first place this seems unnecessary to do. If a combination isn't valid in the first place that stack should not allow setting it. This is a code simplication especially for add new GSO types. Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-14GSO: Support partial segmentation offloadAlexander Duyck
This patch adds support for something I am referring to as GSO partial. The basic idea is that we can support a broader range of devices for segmentation if we use fixed outer headers and have the hardware only really deal with segmenting the inner header. The idea behind the naming is due to the fact that everything before csum_start will be fixed headers, and everything after will be the region that is handled by hardware. With the current implementation it allows us to add support for the following GSO types with an inner TSO_MANGLEID or TSO6 offload: NETIF_F_GSO_GRE NETIF_F_GSO_GRE_CSUM NETIF_F_GSO_IPIP NETIF_F_GSO_SIT NETIF_F_UDP_TUNNEL NETIF_F_UDP_TUNNEL_CSUM In the case of hardware that already supports tunneling we may be able to extend this further to support TSO_TCPV4 without TSO_MANGLEID if the hardware can support updating inner IPv4 headers. Signed-off-by: Alexander Duyck <aduyck@mirantis.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-14GRO: Add support for TCP with fixed IPv4 ID field, limit tunnel IP ID valuesAlexander Duyck
This patch does two things. First it allows TCP to aggregate TCP frames with a fixed IPv4 ID field. As a result we should now be able to aggregate flows that were converted from IPv6 to IPv4. In addition this allows us more flexibility for future implementations of segmentation as we may be able to use a fixed IP ID when segmenting the flow. The second thing this does is that it places limitations on the outer IPv4 ID header in the case of tunneled frames. Specifically it forces the IP ID to be incrementing by 1 unless the DF bit is set in the outer IPv4 header. This way we can avoid creating overlapping series of IP IDs that could possibly be fragmented if the frame goes through GRO and is then resegmented via GSO. Signed-off-by: Alexander Duyck <aduyck@mirantis.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-14GSO: Add GSO type for fixed IPv4 IDAlexander Duyck
This patch adds support for TSO using IPv4 headers with a fixed IP ID field. This is meant to allow us to do a lossless GRO in the case of TCP flows that use a fixed IP ID such as those that convert IPv6 header to IPv4 headers. In addition I am adding a feature that for now I am referring to TSO with IP ID mangling. Basically when this flag is enabled the device has the option to either output the flow with incrementing IP IDs or with a fixed IP ID regardless of what the original IP ID ordering was. This is useful in cases where the DF bit is set and we do not care if the original IP ID value is maintained. Signed-off-by: Alexander Duyck <aduyck@mirantis.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-11net: Store checksum result for offloaded GSO checksumsAlexander Duyck
This patch makes it so that we can offload the checksums for a packet up to a certain point and then begin computing the checksums via software. Setting this up is fairly straight forward as all we need to do is reset the values stored in csum and csum_start for the GSO context block. One complication for this is remote checksum offload. In order to allow the inner checksums to be offloaded while computing the outer checksum manually we needed to have some way of indicating that the offload wasn't real. In order to do that I replaced CHECKSUM_PARTIAL with CHECKSUM_UNNECESSARY in the case of us computing checksums for the outer header while skipping computing checksums for the inner headers. We clean up the ip_summed flag and set it to either CHECKSUM_PARTIAL or CHECKSUM_NONE once we hand the packet off to the next lower level. Signed-off-by: Alexander Duyck <aduyck@mirantis.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-11tcp: reserve tcp_skb_mss() to tcp stackEric Dumazet
tcp_gso_segment() and tcp_gro_receive() are not strictly part of TCP stack. They should not assume tcp_skb_mss(skb) is in fact skb_shinfo(skb)->gso_size. This will allow us to change tcp_skb_mss() in following patches. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-28tcp: cleanup static functionsEric Dumazet
tcp_fastopen_create_child() is static and should not be exported. tcp4_gso_segment() and tcp6_gso_segment() should be static. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-05net: Remove MPLS GSO feature.Pravin B Shelar
Device can export MPLS GSO support in dev->mpls_features same way it export vlan features in dev->vlan_features. So it is safe to remove NETIF_F_GSO_MPLS redundant flag. Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
2014-11-05udp: Changes to udp_offload to support remote checksum offloadTom Herbert
Add a new GSO type, SKB_GSO_TUNNEL_REMCSUM, which indicates remote checksum offload being done (in this case inner checksum must not be offloaded to the NIC). Added logic in __skb_udp_tunnel_segment to handle remote checksum offload case. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-26net: Remove gso_send_check as an offload callbackTom Herbert
The send_check logic was only interesting in cases of TCP offload and UDP UFO where the checksum needed to be initialized to the pseudo header checksum. Now we've moved that logic into the related gso_segment functions so gso_send_check is no longer needed. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-26tcp: move logic out of tcp_v[64]_gso_send_checkTom Herbert
In tcp_v[46]_gso_send_check the TCP checksum is initialized to the pseudo header checksum using __tcp_v[46]_send_check. We can move this logic into new tcp[46]_gso_segment functions to be done when ip_summed != CHECKSUM_PARTIAL (ip_summed == CHECKSUM_PARTIAL should be the common case, possibly always true when taking GSO path). After this change tcp_v[46]_gso_send_check is no-op. Signed-off-by: Tom Herbert <therbert@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-24tcp: Call skb_gro_checksum_validateTom Herbert
In tcp[64]_gro_receive call skb_gro_checksum_validate to validate TCP checksum in the gro context. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-06net-timestamp: cumulative tcp timestamping fixesWillem de Bruijn
A set of small fixes pointed out just after the merge: - make tcp_tx_timestamp static - make tcp_gso_tstamp static - use before() to compare TCP seqno, instead of cast to u64 - add tstamp to tx_flags in GSO, instead of overwrite tx_flags - record skb_shinfo(skb)->tskey for all timestamps, also HW. - optimization in tcp_tx_timestamp: call sock_tx_timestamp only if a tstamp option is set. Signed-off-by: Willem de Bruijn <willemb@google.com> Fixes: 4ed2d765dfac ("net-timestamp: TCP timestamping") Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-05net-timestamp: TCP timestampingWillem de Bruijn
TCP timestamping extends SO_TIMESTAMPING to bytestreams. Bytestreams do not have a 1:1 relationship between send() buffers and network packets. The feature interprets a send call on a bytestream as a request for a timestamp for the last byte in that send() buffer. The choice corresponds to a request for a timestamp when all bytes in the buffer have been sent. That assumption depends on in-order kernel transmission. This is the common case. That said, it is possible to construct a traffic shaping tree that would result in reordering. The guarantee is strong, then, but not ironclad. This implementation supports send and sendpages (splice). GSO replaces one large packet with multiple smaller packets. This patch also copies the option into the correct smaller packet. This patch does not yet support timestamping on data in an initial TCP Fast Open SYN, because that takes a very different data path. If ID generation in ee_data is enabled, bytestream timestamps return a byte offset, instead of the packet counter for datagrams. The implementation supports a single timestamp per packet. It silenty replaces requests for previous timestamps. To avoid missing tstamps, flush the tcp queue by disabling Nagle, cork and autocork. Missing tstamps can be detected by offset when the ee_data ID is enabled. Implementation details: - On GSO, the timestamping code can be included in the main loop. I moved it into its own loop to reduce the impact on the common case to a single branch. - To avoid leaking the absolute seqno to userspace, the offset returned in ee_data must always be relative. It is an offset between an skb and sk field. The first is always set (also for GSO & ACK). The second must also never be uninitialized. Only allow the ID option on sockets in the ESTABLISHED state, for which the seqno is available. Never reset it to zero (instead, move it to the current seqno when reenabling the option). Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16net-gre-gro: Fix a bug that breaks the forwarding pathJerry Chu
Fixed a bug that was introduced by my GRE-GRO patch (bf5a755f5e9186406bbf50f4087100af5bd68e40 net-gre-gro: Add GRE support to the GRO stack) that breaks the forwarding path because various GSO related fields were not set. The bug will cause on the egress path either the GSO code to fail, or a GRE-TSO capable (NETIF_F_GSO_GRE) NICs to choke. The following fix has been tested for both cases. Signed-off-by: H.K. Jerry Chu <hkchu@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-04gre: Call gso_make_checksumTom Herbert
Call gso_make_checksum. This should have the benefit of using a checksum that may have been previously computed for the packet. This also adds NETIF_F_GSO_GRE_CSUM to differentiate devices that offload GRE GSO with and without the GRE checksum offloaed. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-04net: Add GSO support for UDP tunnels with checksumTom Herbert
Added a new netif feature for GSO_UDP_TUNNEL_CSUM. This indicates that a device is capable of computing the UDP checksum in the encapsulating header of a UDP tunnel. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-04tcp: Call gso_make_checksumTom Herbert
Call common gso_make_checksum when calculating checksum for a TCP GSO segment. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-14tcp: do not export tcp_gso_segment() and tcp_gro_receive()Eric Dumazet
tcp_gso_segment() and tcp_gro_receive() no longer need to be exported. IPv4 and IPv6 offloads are statically linked. Note that tcp_gro_complete() is still used by bnx2x, unfortunately. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-07net-gre-gro: Add GRE support to the GRO stackJerry Chu
This patch built on top of Commit 299603e8370a93dd5d8e8d800f0dff1ce2c53d36 ("net-gro: Prepare GRO stack for the upcoming tunneling support") to add the support of the standard GRE (RFC1701/RFC2784/RFC2890) to the GRO stack. It also serves as an example for supporting other encapsulation protocols in the GRO stack in the future. The patch supports version 0 and all the flags (key, csum, seq#) but will flush any pkt with the S (seq#) flag. This is because the S flag is not support by GSO, and a GRO pkt may end up in the forwarding path, thus requiring GSO support to break it up correctly. Currently the "packet_offload" structure only contains L3 (ETH_P_IP/ ETH_P_IPV6) GRO offload support so the encapped pkts are limited to IP pkts (i.e., w/o L2 hdr). But support for other protocol type can be easily added, so is the support for GRE variations like NVGRE. The patch also support csum offload. Specifically if the csum flag is on and the h/w is capable of checksumming the payload (CHECKSUM_COMPLETE), the code will take advantage of the csum computed by the h/w when validating the GRE csum. Note that commit 60769a5dcd8755715c7143b4571d5c44f01796f1 "ipv4: gre: add GRO capability" already introduces GRO capability to IPv4 GRE tunnels, using the gro_cells infrastructure. But GRO is done after GRE hdr has been removed (i.e., decapped). The following patch applies GRO when pkts first come in (before hitting the GRE tunnel code). There is some performance advantage for applying GRO as early as possible. Also this approach is transparent to other subsystem like Open vSwitch where GRE decap is handled outside of the IP stack hence making it harder for the gro_cells stuff to apply. On the other hand, some NICs are still not capable of hashing on the inner hdr of a GRE pkt (RSS). In that case the GRO processing of pkts from the same remote host will all happen on the same CPU and the performance may be suboptimal. I'm including some rough preliminary performance numbers below. Note that the performance will be highly dependent on traffic load, mix as usual. Moreover it also depends on NIC offload features hence the following is by no means a comprehesive study. Local testing and tuning will be needed to decide the best setting. All tests spawned 50 copies of netperf TCP_STREAM and ran for 30 secs. (super_netperf 50 -H 192.168.1.18 -l 30) An IP GRE tunnel with only the key flag on (e.g., ip tunnel add gre1 mode gre local 10.246.17.18 remote 10.246.17.17 ttl 255 key 123) is configured. The GRO support for pkts AFTER decap are controlled through the device feature of the GRE device (e.g., ethtool -K gre1 gro on/off). 1.1 ethtool -K gre1 gro off; ethtool -K eth0 gro off thruput: 9.16Gbps CPU utilization: 19% 1.2 ethtool -K gre1 gro on; ethtool -K eth0 gro off thruput: 5.9Gbps CPU utilization: 15% 1.3 ethtool -K gre1 gro off; ethtool -K eth0 gro on thruput: 9.26Gbps CPU utilization: 12-13% 1.4 ethtool -K gre1 gro on; ethtool -K eth0 gro on thruput: 9.26Gbps CPU utilization: 10% The following tests were performed on a different NIC that is capable of csum offload. I.e., the h/w is capable of computing IP payload csum (CHECKSUM_COMPLETE). 2.1 ethtool -K gre1 gro on (hence will use gro_cells) 2.1.1 ethtool -K eth0 gro off; csum offload disabled thruput: 8.53Gbps CPU utilization: 9% 2.1.2 ethtool -K eth0 gro off; csum offload enabled thruput: 8.97Gbps CPU utilization: 7-8% 2.1.3 ethtool -K eth0 gro on; csum offload disabled thruput: 8.83Gbps CPU utilization: 5-6% 2.1.4 ethtool -K eth0 gro on; csum offload enabled thruput: 8.98Gbps CPU utilization: 5% 2.2 ethtool -K gre1 gro off 2.2.1 ethtool -K eth0 gro off; csum offload disabled thruput: 5.93Gbps CPU utilization: 9% 2.2.2 ethtool -K eth0 gro off; csum offload enabled thruput: 5.62Gbps CPU utilization: 8% 2.2.3 ethtool -K eth0 gro on; csum offload disabled thruput: 7.69Gbps CPU utilization: 8% 2.2.4 ethtool -K eth0 gro on; csum offload enabled thruput: 8.96Gbps CPU utilization: 5-6% Signed-off-by: H.K. Jerry Chu <hkchu@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-12net-gro: Prepare GRO stack for the upcoming tunneling supportJerry Chu
This patch modifies the GRO stack to avoid the use of "network_header" and associated macros like ip_hdr() and ipv6_hdr() in order to allow an arbitary number of IP hdrs (v4 or v6) to be used in the encapsulation chain. This lays the foundation for various IP tunneling support (IP-in-IP, GRE, VXLAN, SIT,...) to be added later. With this patch, the GRO stack traversing now is mostly based on skb_gro_offset rather than special hdr offsets saved in skb (e.g., skb->network_header). As a result all but the top layer (i.e., the the transport layer) must have hdrs of the same length in order for a pkt to be considered for aggregation. Therefore when adding a new encap layer (e.g., for tunneling), one must check and skip flows (e.g., by setting NAPI_GRO_CB(p)->same_flow to 0) that have a different hdr length. Note that unlike the network header, the transport header can and will continue to be set by the GRO code since there will be at most one "transport layer" in the encap chain. Signed-off-by: H.K. Jerry Chu <hkchu@google.com> Suggested-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-23gro: Clean up tcpX_gro_receive checksum verificationHerbert Xu
This patch simplifies the checksum verification in tcpX_gro_receive by reusing the CHECKSUM_COMPLETE code for CHECKSUM_NONE. All it does for CHECKSUM_NONE is compute the partial checksum and then treat it as if it came from the hardware (CHECKSUM_COMPLETE). Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Cheers, Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-23gro: Only verify TCP checksums for candidatesHerbert Xu
In some cases we may receive IP packets that are longer than their stated lengths. Such packets are never merged in GRO. However, we may end up computing their checksums incorrectly and end up allowing packets with a bogus checksum enter our stack with the checksum status set as verified. Since such packets are rare and not performance-critical, this patch simply skips the checksum verification for them. Reported-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Alexander Duyck <alexander.h.duyck@intel.com> Thanks, Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/ethernet/emulex/benet/be.h drivers/net/netconsole.c net/bridge/br_private.h Three mostly trivial conflicts. The net/bridge/br_private.h conflict was a function signature (argument addition) change overlapping with the extern removals from Joe Perches. In drivers/net/netconsole.c we had one change adjusting a printk message whilst another changed "printk(KERN_INFO" into "pr_info(". Lastly, the emulex change was a new inline function addition overlapping with Joe Perches's extern removals. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-29tcp: gso: fix truesize trackingEric Dumazet
commit 6ff50cd55545 ("tcp: gso: do not generate out of order packets") had an heuristic that can trigger a warning in skb_try_coalesce(), because skb->truesize of the gso segments were exactly set to mss. This breaks the requirement that skb->truesize >= skb->len + truesizeof(struct sk_buff); It can trivially be reproduced by : ifconfig lo mtu 1500 ethtool -K lo tso off netperf As the skbs are looped into the TCP networking stack, skb_try_coalesce() warns us of these skb under-estimating their truesize. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-21ipv6: sit: add GSO/TSO supportEric Dumazet
Now ipv6_gso_segment() is stackable, its relatively easy to implement GSO/TSO support for SIT tunnels Performance results, when segmentation is done after tunnel device (as no NIC is yet enabled for TSO SIT support) : Before patch : lpq84:~# ./netperf -H 2002:af6:1153:: -Cc MIGRATED TCP STREAM TEST from ::0 (::) port 0 AF_INET6 to 2002:af6:1153:: () port 0 AF_INET6 Recv Send Send Utilization Service Demand Socket Socket Message Elapsed Send Recv Send Recv Size Size Size Time Throughput local remote local remote bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB 87380 16384 16384 10.00 3168.31 4.81 4.64 2.988 2.877 After patch : lpq84:~# ./netperf -H 2002:af6:1153:: -Cc MIGRATED TCP STREAM TEST from ::0 (::) port 0 AF_INET6 to 2002:af6:1153:: () port 0 AF_INET6 Recv Send Send Utilization Service Demand Socket Socket Message Elapsed Send Recv Send Recv Size Size Size Time Throughput local remote local remote bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB 87380 16384 16384 10.00 5525.00 7.76 5.17 2.763 1.840 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-19ipip: add GSO/TSO supportEric Dumazet
Now inet_gso_segment() is stackable, its relatively easy to implement GSO/TSO support for IPIP Performance results, when segmentation is done after tunnel device (as no NIC is yet enabled for TSO IPIP support) : Before patch : lpq83:~# ./netperf -H 7.7.9.84 -Cc MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.9.84 () port 0 AF_INET Recv Send Send Utilization Service Demand Socket Socket Message Elapsed Send Recv Send Recv Size Size Size Time Throughput local remote local remote bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB 87380 16384 16384 10.00 3357.88 5.09 3.70 2.983 2.167 After patch : lpq83:~# ./netperf -H 7.7.9.84 -Cc MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.9.84 () port 0 AF_INET Recv Send Send Utilization Service Demand Socket Socket Message Elapsed Send Recv Send Recv Size Size Size Time Throughput local remote local remote bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB 87380 16384 16384 10.00 7710.19 4.52 6.62 1.152 1.687 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-18tcp: rename tcp_tso_segment()Eric Dumazet
Rename tcp_tso_segment() to tcp_gso_segment(), to better reflect what is going on, and ease grep games. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-07net: tcp: move GRO/GSO functions to tcp_offloadDaniel Borkmann
Would be good to make things explicit and move those functions to a new file called tcp_offload.c, thus make this similar to tcpv6_offload.c. While moving all related functions into tcp_offload.c, we can also make some of them static, since they are only used there. Also, add an explicit registration function. Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>