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* net: igmp: Reduce Unsolicited report interval to 1s when using IGMPv3William Manley2013-08-091-3/+13
| | | | | | | | | | | | | | | | | | | | | | | | | If an IGMP join packet is lost you will not receive data sent to the multicast group so if no data arrives from that multicast group in a period of time after the IGMP join a second IGMP join will be sent. The delay between joins is the "IGMP Unsolicited Report Interval". Previously this value was hard coded to be chosen randomly between 0-10s. This can be too long for some use-cases, such as IPTV as it can cause channel change to be slow in the presence of packet loss. The value 10s has come from IGMPv2 RFC2236, which was reduced to 1s in IGMPv3 RFC3376. This patch makes the kernel use the 1s value from the later RFC if we are operating in IGMPv3 mode. IGMPv2 behaviour is unaffected. Tested with Wireshark and a simple program to join a (non-existent) multicast group. The distribution of timings for the second join differ based upon setting /proc/sys/net/ipv4/conf/eth0/force_igmp_version. Signed-off-by: William Manley <william.manley@youview.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Benjamin LaHaise <bcrl@kvack.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: add SNMP counters tracking incoming ECN bitsEric Dumazet2013-08-092-1/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | With GRO/LRO processing, there is a problem because Ip[6]InReceives SNMP counters do not count the number of frames, but number of aggregated segments. Its probably too late to change this now. This patch adds four new counters, tracking number of frames, regardless of LRO/GRO, and on a per ECN status basis, for IPv4 and IPv6. Ip[6]NoECTPkts : Number of packets received with NOECT Ip[6]ECT1Pkts : Number of packets received with ECT(1) Ip[6]ECT0Pkts : Number of packets received with ECT(0) Ip[6]CEPkts : Number of packets received with Congestion Experienced lph37:~# nstat | egrep "Pkts|InReceive" IpInReceives 1634137 0.0 Ip6InReceives 3714107 0.0 Ip6InNoECTPkts 19205 0.0 Ip6InECT0Pkts 52651828 0.0 IpExtInNoECTPkts 33630 0.0 IpExtInECT0Pkts 15581379 0.0 IpExtInCEPkts 6 0.0 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ip_tunnel: embed hash list headstephen hemminger2013-08-081-7/+6Star
| | | | | | | | | | | | | The IP tunnel hash heads can be embedded in the per-net structure since it is a fixed size. Reduce the size so that the total structure fits in a page size. The original size was overly large, even NETDEV_HASHBITS is only 8 bits! Also, add some white space for readability. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Acked-by: Pravin B Shelar <pshelar@nicira.com>. Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2013-08-043-3/+9
|\ | | | | | | | | | | | | Merge net into net-next to setup some infrastructure Eric Dumazet needs for usbnet changes. Signed-off-by: David S. Miller <davem@davemloft.net>
| * net: rtm_to_ifaddr: free ifa if ifa_cacheinfo processing failsDaniel Borkmann2013-08-021-1/+3
| | | | | | | | | | | | | | | | | | | | Commit 5c766d642 ("ipv4: introduce address lifetime") leaves the ifa resource that was allocated via inet_alloc_ifa() unfreed when returning the function with -EINVAL. Thus, free it first via inet_free_ifa(). Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Reviewed-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
| * fib_trie: potential out of bounds access in trie_show_stats()Jerry Snitselaar2013-07-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | With the <= max condition in the for loop, it will be always go 1 element further than needed. If the condition for the while loop is never met, then max is MAX_STAT_DEPTH, and for loop will walk off the end of nodesizes[]. Signed-off-by: Jerry Snitselaar <jerry.snitselaar@oracle.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| * sysctl net: Keep tcp_syn_retries inside the boundaryMichal Tesar2013-07-201-1/+5
| | | | | | | | | | | | | | | | Limit the min/max value passed to the /proc/sys/net/ipv4/tcp_syn_retries. Signed-off-by: Michal Tesar <mtesar@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | fib_rules: fix suppressor names and default valuesStefan Tomanek2013-08-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change brings the suppressor attribute names into line; it also changes the data types to provide a more consistent interface. While -1 indicates that the suppressor is not enabled, values >= 0 for suppress_prefixlen or suppress_ifgroup reject routing decisions violating the constraint. This changes the previously presented behaviour of suppress_prefixlen, where a prefix length _less_ than the attribute value was rejected. After this change, a prefix length less than *or* equal to the value is considered a violation of the rule constraint. It also changes the default values for default and newly added rules (disabling any suppression for those). Signed-off-by: Stefan Tomanek <stefan.tomanek@wertarbyte.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | fib_rules: add route suppression based on ifgroupStefan Tomanek2013-08-031-6/+17
| | | | | | | | | | | | | | | | | | This change adds the ability to suppress a routing decision based upon the interface group the selected interface belongs to. This allows it to exclude specific devices from a routing decision. Signed-off-by: Stefan Tomanek <stefan.tomanek@wertarbyte.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | fib_rules: add .suppress operationStefan Tomanek2013-08-011-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change adds a new operation to the fib_rules_ops struct; it allows the suppression of routing decisions if certain criteria are not met by its results. The first implemented constraint is a minimum prefix length added to the structures of routing rules. If a rule is added with a minimum prefix length >0, only routes meeting this threshold will be considered. Any other (more general) routing table entries will be ignored. When configuring a system with multiple network uplinks and default routes, it is often convinient to reference the main routing table multiple times - but omitting the default route. Using this patch and a modified "ip" utility, this can be achieved by using the following command sequence: $ ip route add table secuplink default via 10.42.23.1 $ ip rule add pref 100 table main prefixlength 1 $ ip rule add pref 150 fwmark 0xA table secuplink With this setup, packets marked 0xA will be processed by the additional routing table "secuplink", but only if no suitable route in the main routing table can be found. By using a minimal prefixlength of 1, the default route (/0) of the table "main" is hidden to packets processed by rule 100; packets traveling to destinations with more specific routing entries are processed as usual. Signed-off-by: Stefan Tomanek <stefan.tomanek@wertarbyte.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: split rt_genid for ipv4 and ipv6fan.du2013-07-311-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Current net name space has only one genid for both IPv4 and IPv6, it has below drawbacks: - Add/delete an IPv4 address will invalidate all IPv6 routing table entries. - Insert/remove XFRM policy will also invalidate both IPv4/IPv6 routing table entries even when the policy is only applied for one address family. Thus, this patch attempt to split one genid for two to cater for IPv4 and IPv6 separately in a fine granularity. Signed-off-by: Fan Du <fan.du@windriver.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: Remove unused tcpct declarations and commentsDmitry Popov2013-07-311-4/+0Star
| | | | | | | | | | | | | | | | | | Remove declaration, 4 defines and confusing comment that are no longer used since 1a2c6181c4 ("tcp: Remove TCPCT"). Signed-off-by: Dmitry Popov <dp@highloadlab.com> Acked-by: Christoph Paasch <christoph.paasch@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: remove an unneeded checkDan Carpenter2013-07-311-4/+1Star
| | | | | | | | | | | | | | | | | | "ifa->ifa_label" is an array inside the in_ifaddr struct. It can never be NULL so we can remove this check. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: add tcp_syncookies mode to allow unconditionally generation of syncookiesHannes Frederic Sowa2013-07-311-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | If you want to test which effects syncookies have to your | network connections you can set this knob to 2 to enable | unconditionally generation of syncookies. Original idea and first implementation by Eric Dumazet. Cc: Florian Westphal <fw@strlen.de> Cc: David Miller <davem@davemloft.net> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv4, ipv6: send igmpv3/mld packets with TC_PRIO_CONTROLHannes Frederic Sowa2013-07-281-0/+3
| | | | | | | | | | | | | | | | | | | | | | v2: a) Also send ipv4 igmp messages with TC_PRIO_CONTROL Cc: William Manley <william.manley@youview.com> Cc: Lukas Tribus <luky-37@hotmail.com> Acked-by: Benjamin LaHaise <bcrl@kvack.org> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* | pktgen: Add UDPCSUM flag to support UDP checksumsThomas Graf2013-07-281-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | UDP checksums are optional, hence pktgen has been omitting them in favour of performance. The optional flag UDPCSUM enables UDP checksumming. If the output device supports hardware checksumming the skb is prepared and marked CHECKSUM_PARTIAL, otherwise the checksum is generated in software. Signed-off-by: Thomas Graf <tgraf@suug.ch> Cc: Eric Dumazet <edumazet@google.com> Cc: Ben Greear <greearb@candelatech.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: TCP_NOTSENT_LOWAT socket optionEric Dumazet2013-07-254-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Idea of this patch is to add optional limitation of number of unsent bytes in TCP sockets, to reduce usage of kernel memory. TCP receiver might announce a big window, and TCP sender autotuning might allow a large amount of bytes in write queue, but this has little performance impact if a large part of this buffering is wasted : Write queue needs to be large only to deal with large BDP, not necessarily to cope with scheduling delays (incoming ACKS make room for the application to queue more bytes) For most workloads, using a value of 128 KB or less is OK to give applications enough time to react to POLLOUT events in time (or being awaken in a blocking sendmsg()) This patch adds two ways to set the limit : 1) Per socket option TCP_NOTSENT_LOWAT 2) A sysctl (/proc/sys/net/ipv4/tcp_notsent_lowat) for sockets not using TCP_NOTSENT_LOWAT socket option (or setting a zero value) Default value being UINT_MAX (0xFFFFFFFF), meaning this has no effect. This changes poll()/select()/epoll() to report POLLOUT only if number of unsent bytes is below tp->nosent_lowat Note this might increase number of sendmsg()/sendfile() calls when using non blocking sockets, and increase number of context switches for blocking sockets. Note this is not related to SO_SNDLOWAT (as SO_SNDLOWAT is defined as : Specify the minimum number of bytes in the buffer until the socket layer will pass the data to the protocol) Tested: netperf sessions, and watching /proc/net/protocols "memory" column for TCP With 200 concurrent netperf -t TCP_STREAM sessions, amount of kernel memory used by TCP buffers shrinks by ~55 % (20567 pages instead of 45458) lpq83:~# echo -1 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# (super_netperf 200 -t TCP_STREAM -H remote -l 90 &); sleep 60 ; grep TCP /proc/net/protocols TCPv6 1880 2 45458 no 208 yes ipv6 y y y y y y y y y y y y y n y y y y y TCP 1696 508 45458 no 208 yes kernel y y y y y y y y y y y y y n y y y y y lpq83:~# echo 131072 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# (super_netperf 200 -t TCP_STREAM -H remote -l 90 &); sleep 60 ; grep TCP /proc/net/protocols TCPv6 1880 2 20567 no 208 yes ipv6 y y y y y y y y y y y y y n y y y y y TCP 1696 508 20567 no 208 yes kernel y y y y y y y y y y y y y n y y y y y Using 128KB has no bad effect on the throughput or cpu usage of a single flow, although there is an increase of context switches. A bonus is that we hold socket lock for a shorter amount of time and should improve latencies of ACK processing. lpq83:~# echo -1 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# perf stat -e context-switches ./netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3 OMNI Send TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.7.84 () port 0 AF_INET : +/-2.500% @ 99% conf. Local Remote Local Elapsed Throughput Throughput Local Local Remote Remote Local Remote Service Send Socket Recv Socket Send Time Units CPU CPU CPU CPU Service Service Demand Size Size Size (sec) Util Util Util Util Demand Demand Units Final Final % Method % Method 1651584 6291456 16384 20.00 17447.90 10^6bits/s 3.13 S -1.00 U 0.353 -1.000 usec/KB Performance counter stats for './netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3': 412,514 context-switches 200.034645535 seconds time elapsed lpq83:~# echo 131072 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# perf stat -e context-switches ./netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3 OMNI Send TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.7.84 () port 0 AF_INET : +/-2.500% @ 99% conf. Local Remote Local Elapsed Throughput Throughput Local Local Remote Remote Local Remote Service Send Socket Recv Socket Send Time Units CPU CPU CPU CPU Service Service Demand Size Size Size (sec) Util Util Util Util Demand Demand Units Final Final % Method % Method 1593240 6291456 16384 20.00 17321.16 10^6bits/s 3.35 S -1.00 U 0.381 -1.000 usec/KB Performance counter stats for './netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3': 2,675,818 context-switches 200.029651391 seconds time elapsed Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-By: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: add sk_stream_is_writeable() helperEric Dumazet2013-07-251-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Several call sites use the hardcoded following condition : sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) Lets use a helper because TCP_NOTSENT_LOWAT support will change this condition for TCP sockets. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | vti: switch to new ip tunnel codeAmerigo Wang2013-07-241-476/+52Star
| | | | | | | | | | | | | | | | | | | | | | | | GRE tunnel and IPIP tunnel already switched to the new ip tunnel code, VTI tunnel can use it too. Cc: Pravin B Shelar <pshelar@nicira.com> Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: Saurabh Mohan <saurabh.mohan@vyatta.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Cong Wang <amwang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipmr: change the prototype of ip_mr_forward().Rami Rosen2013-07-241-8/+7Star
| | | | | | | | | | | | | | | | | | | | | | | | This patch changes the prototpye of the ip_mr_forward() method to return void instead of int. The ip_mr_forward() method always returns 0; moreover, the return value of this method is not checked anywhere. Signed-off-by: Rami Rosen <ramirose@gmail.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: convert resend IGMP to notifier eventJiri Pirko2013-07-241-6/+40
| | | | | | | | | | | | | | | | | | | | | | | | Until now, bond_resend_igmp_join_requests() looks for vlans attached to bonding device, bridge where bonding act as port manually. It does not care of other scenarios, like stacked bonds or team device above. Make this more generic and use netdev notifier to propagate the event to upper devices and to actually call ip_mc_rejoin_groups(). Signed-off-by: Jiri Pirko <jiri@resnulli.us> Acked-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: use RTT from SACK for RTOYuchung Cheng2013-07-231-9/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If RTT is not available because Karn's check has failed or no new packet is acked, use the RTT measured from SACK to estimate the RTO. The sender can continue to estimate the RTO during loss recovery or reordering event upon receiving non-partial ACKs. This also changes when the RTO is re-armed. Previously it is only re-armed when some data is cummulatively acknowledged (i.e., SND.UNA advances), but now it is re-armed whenever RTT estimator is updated. This feature is particularly useful to reduce spurious timeout for buffer bloat including cellular carriers [1], and RTT estimation on reordering events. [1] "An In-depth Study of LTE: Effect of Network Protocol and Application Behavior on Performance", In Proc. of SIGCOMM 2013 Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: measure RTT from new SACKYuchung Cheng2013-07-231-6/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Take RTT sample if an ACK selectively acks some sequences that have never been retransmitted. The Karn's algorithm does not apply even if that ACK (s)acks other retransmitted sequences, because it must been generated by an original but perhaps out-of-order packet. There is no ambiguity. In case when multiple blocks are newly sacked because of ACK losses the earliest block is used to measure RTT, similar to cummulative ACKs. Such RTT samples allow the sender to estimate the RTO during loss recovery and packet reordering events. It is still useful even with TCP timestamps. That's because during these events the SND.UNA may not advance preventing RTT samples from TS ECR (thus the FLAG_ACKED check before calling tcp_ack_update_rtt()). Therefore this new RTT source is complementary to existing ACK and TS RTT mechanisms. This patch does not update the RTO. It is done in the next patch. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: prefer packet timing to TS-ECR for RTTYuchung Cheng2013-07-231-49/+18Star
| | | | | | | | | | | | | | | | | | | | | | | | | | Prefer packet timings to TS-ecr for RTT measurements when both sources are available. That's because broken middle-boxes and remote peer can return packets with corrupted TS ECR fields. Similarly most congestion controls that require RTT signals favor timing-based sources as well. Also check for bad TS ECR values to avoid RTT blow-ups. It has happened on production Web servers. Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: consolidate SYNACK RTT samplingYuchung Cheng2013-07-233-10/+14
|/ | | | | | | | | | The first patch consolidates SYNACK and other RTT measurement to use a central function tcp_ack_update_rtt(). A (small) bonus is now SYNACK RTT measurement happens after PAWS check, potentially reducing the impact of RTO seeding on bad TCP timestamps values. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: set transport header earlierEric Dumazet2013-07-161-4/+3Star
| | | | | | | | | | | | | | | | | | | | | | | | | commit 45f00f99d6e ("ipv4: tcp: clean up tcp_v4_early_demux()") added a performance regression for non GRO traffic, basically disabling IP early demux. IPv6 stack resets transport header in ip6_rcv() before calling IP early demux in ip6_rcv_finish(), while IPv4 does this only in ip_local_deliver_finish(), _after_ IP early demux. GRO traffic happened to enable IP early demux because transport header is also set in inet_gro_receive() Instead of reverting the faulty commit, we can make IPv4/IPv6 behave the same : transport_header should be set in ip_rcv() instead of ip_local_deliver_finish() ip_local_deliver_finish() can also use skb_network_header_len() which is faster than ip_hdrlen() Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: account all retransmit failuresYuchung Cheng2013-07-131-3/+4
| | | | | | | | | | Change snmp RETRANSFAILS stat to include timeout retransmit failures in addition to other loss recoveries. Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* gre: Fix MTU sizing check for gretap tunnelsAlexander Duyck2013-07-121-1/+1
| | | | | | | | | | | | | | | | | | | This change fixes an MTU sizing issue seen with gretap tunnels when non-gso packets are sent from the interface. In my case I was able to reproduce the issue by simply sending a ping of 1421 bytes with the gretap interface created on a device with a standard 1500 mtu. This fix is based on the fact that the tunnel mtu is already adjusted by dev->hard_header_len so it would make sense that any packets being compared against that mtu should also be adjusted by hard_header_len and the tunnel header instead of just the tunnel header. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Reported-by: Cong Wang <amwang@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* gso: Update tunnel segmentation to support Tx checksum offloadAlexander Duyck2013-07-112-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change makes it so that the GRE and VXLAN tunnels can make use of Tx checksum offload support provided by some drivers via the hw_enc_features. Without this fix enabling GSO means sacrificing Tx checksum offload and this actually leads to a performance regression as shown below: Utilization Send Throughput local GSO 10^6bits/s % S state 6276.51 8.39 enabled 7123.52 8.42 disabled To resolve this it was necessary to address two items. First netif_skb_features needed to be updated so that it would correctly handle the Trans Ether Bridging protocol without impacting the need to check for Q-in-Q tagging. To do this it was necessary to update harmonize_features so that it used skb_network_protocol instead of just using the outer protocol. Second it was necessary to update the GRE and UDP tunnel segmentation offloads so that they would reset the encapsulation bit and inner header offsets after the offload was complete. As a result of this change I have seen the following results on a interface with Tx checksum enabled for encapsulated frames: Utilization Send Throughput local GSO 10^6bits/s % S state 7123.52 8.42 disabled 8321.75 5.43 enabled v2: Instead of replacing refrence to skb->protocol with skb_network_protocol just replace the protocol reference in harmonize_features to allow for double VLAN tag checks. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* inet: fix spacing in assignmentCamelia Groza2013-07-111-1/+1
| | | | | | | Found using checkpatch.pl Signed-off-by: Camelia Groza <camelia.groza@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: rename ll methods to busy-pollEliezer Tamir2013-07-112-2/+2
| | | | | | | | | | | Rename ndo_ll_poll to ndo_busy_poll. Rename sk_mark_ll to sk_mark_napi_id. Rename skb_mark_ll to skb_mark_napi_id. Correct all useres of these functions. Update comments and defines in include/net/busy_poll.h Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: rename include/net/ll_poll.h to include/net/busy_poll.hEliezer Tamir2013-07-113-3/+3
| | | | | | | Rename the file and correct all the places where it is included. Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds2013-07-1039-1709/+2236
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking updates from David Miller: "This is a re-do of the net-next pull request for the current merge window. The only difference from the one I made the other day is that this has Eliezer's interface renames and the timeout handling changes made based upon your feedback, as well as a few bug fixes that have trickeled in. Highlights: 1) Low latency device polling, eliminating the cost of interrupt handling and context switches. Allows direct polling of a network device from socket operations, such as recvmsg() and poll(). Currently ixgbe, mlx4, and bnx2x support this feature. Full high level description, performance numbers, and design in commit 0a4db187a999 ("Merge branch 'll_poll'") From Eliezer Tamir. 2) With the routing cache removed, ip_check_mc_rcu() gets exercised more than ever before in the case where we have lots of multicast addresses. Use a hash table instead of a simple linked list, from Eric Dumazet. 3) Add driver for Atheros CQA98xx 802.11ac wireless devices, from Bartosz Markowski, Janusz Dziedzic, Kalle Valo, Marek Kwaczynski, Marek Puzyniak, Michal Kazior, and Sujith Manoharan. 4) Support reporting the TUN device persist flag to userspace, from Pavel Emelyanov. 5) Allow controlling network device VF link state using netlink, from Rony Efraim. 6) Support GRE tunneling in openvswitch, from Pravin B Shelar. 7) Adjust SOCK_MIN_RCVBUF and SOCK_MIN_SNDBUF for modern times, from Daniel Borkmann and Eric Dumazet. 8) Allow controlling of TCP quickack behavior on a per-route basis, from Cong Wang. 9) Several bug fixes and improvements to vxlan from Stephen Hemminger, Pravin B Shelar, and Mike Rapoport. In particular, support receiving on multiple UDP ports. 10) Major cleanups, particular in the area of debugging and cookie lifetime handline, to the SCTP protocol code. From Daniel Borkmann. 11) Allow packets to cross network namespaces when traversing tunnel devices. From Nicolas Dichtel. 12) Allow monitoring netlink traffic via AF_PACKET sockets, in a manner akin to how we monitor real network traffic via ptype_all. From Daniel Borkmann. 13) Several bug fixes and improvements for the new alx device driver, from Johannes Berg. 14) Fix scalability issues in the netem packet scheduler's time queue, by using an rbtree. From Eric Dumazet. 15) Several bug fixes in TCP loss recovery handling, from Yuchung Cheng. 16) Add support for GSO segmentation of MPLS packets, from Simon Horman. 17) Make network notifiers have a real data type for the opaque pointer that's passed into them. Use this to properly handle network device flag changes in arp_netdev_event(). From Jiri Pirko and Timo Teräs. 18) Convert several drivers over to module_pci_driver(), from Peter Huewe. 19) tcp_fixup_rcvbuf() can loop 500 times over loopback, just use a O(1) calculation instead. From Eric Dumazet. 20) Support setting of explicit tunnel peer addresses in ipv6, just like ipv4. From Nicolas Dichtel. 21) Protect x86 BPF JIT against spraying attacks, from Eric Dumazet. 22) Prevent a single high rate flow from overruning an individual cpu during RX packet processing via selective flow shedding. From Willem de Bruijn. 23) Don't use spinlocks in TCP md5 signing fast paths, from Eric Dumazet. 24) Don't just drop GSO packets which are above the TBF scheduler's burst limit, chop them up so they are in-bounds instead. Also from Eric Dumazet. 25) VLAN offloads are missed when configured on top of a bridge, fix from Vlad Yasevich. 26) Support IPV6 in ping sockets. From Lorenzo Colitti. 27) Receive flow steering targets should be updated at poll() time too, from David Majnemer. 28) Fix several corner case regressions in PMTU/redirect handling due to the routing cache removal, from Timo Teräs. 29) We have to be mindful of ipv4 mapped ipv6 sockets in upd_v6_push_pending_frames(). From Hannes Frederic Sowa. 30) Fix L2TP sequence number handling bugs, from James Chapman." * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1214 commits) drivers/net: caif: fix wrong rtnl_is_locked() usage drivers/net: enic: release rtnl_lock on error-path vhost-net: fix use-after-free in vhost_net_flush net: mv643xx_eth: do not use port number as platform device id net: sctp: confirm route during forward progress virtio_net: fix race in RX VQ processing virtio: support unlocked queue poll net/cadence/macb: fix bug/typo in extracting gem_irq_read_clear bit Documentation: Fix references to defunct linux-net@vger.kernel.org net/fs: change busy poll time accounting net: rename low latency sockets functions to busy poll bridge: fix some kernel warning in multicast timer sfc: Fix memory leak when discarding scattered packets sit: fix tunnel update via netlink dt:net:stmmac: Add dt specific phy reset callback support. dt:net:stmmac: Add support to dwmac version 3.610 and 3.710 dt:net:stmmac: Allocate platform data only if its NULL. net:stmmac: fix memleak in the open method ipv6: rt6_check_neigh should successfully verify neigh if no NUD information are available net: ipv6: fix wrong ping_v6_sendmsg return value ...
| * net: rename low latency sockets functions to busy pollEliezer Tamir2013-07-091-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Rename functions in include/net/ll_poll.h to busy wait. Clarify documentation about expected power use increase. Rename POLL_LL to POLL_BUSY_LOOP. Add need_resched() testing to poll/select busy loops. Note, that in select and poll can_busy_poll is dynamic and is updated continuously to reflect the existence of supported sockets with valid queue information. Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2013-07-033-7/+11
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: drivers/net/ethernet/freescale/fec_main.c drivers/net/ethernet/renesas/sh_eth.c net/ipv4/gre.c The GRE conflict is between a bug fix (kfree_skb --> kfree_skb_list) and the splitting of the gre.c code into seperate files. The FEC conflict was two sets of changes adding ethtool support code in an "!CONFIG_M5272" CPP protected block. Finally the sh_eth.c conflict was between one commit add bits set in the .eesr_err_check mask whilst another commit removed the .tx_error_check member and assignments. Signed-off-by: David S. Miller <davem@davemloft.net>
| * | net: gre: move GSO functions to gre_offloadDaniel Borkmann2013-07-033-103/+131
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Similarly to TCP/UDP offloading, move all related GRE functions to gre_offload.c to make things more explicit and similar to the rest of the code. Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | ip_tunnels: Use skb-len to PMTU check.Pravin B Shelar2013-07-031-44/+55
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In path mtu check, ip header total length works for gre device but not for gre-tap device. Use skb len which is consistent for all tunneling types. This is old bug in gre. This also fixes mtu calculation bug introduced by commit c54419321455631079c7d (GRE: Refactor GRE tunneling code). Reported-by: Timo Teras <timo.teras@iki.fi> Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | ipv6: call udp_push_pending_frames when uncorking a socket with AF_INET ↵Hannes Frederic Sowa2013-07-021-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pending data We accidentally call down to ip6_push_pending_frames when uncorking pending AF_INET data on a ipv6 socket. This results in the following splat (from Dave Jones): skbuff: skb_under_panic: text:ffffffff816765f6 len:48 put:40 head:ffff88013deb6df0 data:ffff88013deb6dec tail:0x2c end:0xc0 dev:<NULL> ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:126! invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: dccp_ipv4 dccp 8021q garp bridge stp dlci mpoa snd_seq_dummy sctp fuse hidp tun bnep nfnetlink scsi_transport_iscsi rfcomm can_raw can_bcm af_802154 appletalk caif_socket can caif ipt_ULOG x25 rose af_key pppoe pppox ipx phonet irda llc2 ppp_generic slhc p8023 psnap p8022 llc crc_ccitt atm bluetooth +netrom ax25 nfc rfkill rds af_rxrpc coretemp hwmon kvm_intel kvm crc32c_intel snd_hda_codec_realtek ghash_clmulni_intel microcode pcspkr snd_hda_codec_hdmi snd_hda_intel snd_hda_codec snd_hwdep usb_debug snd_seq snd_seq_device snd_pcm e1000e snd_page_alloc snd_timer ptp snd pps_core soundcore xfs libcrc32c CPU: 2 PID: 8095 Comm: trinity-child2 Not tainted 3.10.0-rc7+ #37 task: ffff8801f52c2520 ti: ffff8801e6430000 task.ti: ffff8801e6430000 RIP: 0010:[<ffffffff816e759c>] [<ffffffff816e759c>] skb_panic+0x63/0x65 RSP: 0018:ffff8801e6431de8 EFLAGS: 00010282 RAX: 0000000000000086 RBX: ffff8802353d3cc0 RCX: 0000000000000006 RDX: 0000000000003b90 RSI: ffff8801f52c2ca0 RDI: ffff8801f52c2520 RBP: ffff8801e6431e08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffff88022ea0c800 R13: ffff88022ea0cdf8 R14: ffff8802353ecb40 R15: ffffffff81cc7800 FS: 00007f5720a10740(0000) GS:ffff880244c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000005862000 CR3: 000000022843c000 CR4: 00000000001407e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Stack: ffff88013deb6dec 000000000000002c 00000000000000c0 ffffffff81a3f6e4 ffff8801e6431e18 ffffffff8159a9aa ffff8801e6431e90 ffffffff816765f6 ffffffff810b756b 0000000700000002 ffff8801e6431e40 0000fea9292aa8c0 Call Trace: [<ffffffff8159a9aa>] skb_push+0x3a/0x40 [<ffffffff816765f6>] ip6_push_pending_frames+0x1f6/0x4d0 [<ffffffff810b756b>] ? mark_held_locks+0xbb/0x140 [<ffffffff81694919>] udp_v6_push_pending_frames+0x2b9/0x3d0 [<ffffffff81694660>] ? udplite_getfrag+0x20/0x20 [<ffffffff8162092a>] udp_lib_setsockopt+0x1aa/0x1f0 [<ffffffff811cc5e7>] ? fget_light+0x387/0x4f0 [<ffffffff816958a4>] udpv6_setsockopt+0x34/0x40 [<ffffffff815949f4>] sock_common_setsockopt+0x14/0x20 [<ffffffff81593c31>] SyS_setsockopt+0x71/0xd0 [<ffffffff816f5d54>] tracesys+0xdd/0xe2 Code: 00 00 48 89 44 24 10 8b 87 d8 00 00 00 48 89 44 24 08 48 8b 87 e8 00 00 00 48 c7 c7 c0 04 aa 81 48 89 04 24 31 c0 e8 e1 7e ff ff <0f> 0b 55 48 89 e5 0f 0b 55 48 89 e5 0f 0b 55 48 89 e5 0f 0b 55 RIP [<ffffffff816e759c>] skb_panic+0x63/0x65 RSP <ffff8801e6431de8> This patch adds a check if the pending data is of address family AF_INET and directly calls udp_push_ending_frames from udp_v6_push_pending_frames if that is the case. This bug was found by Dave Jones with trinity. (Also move the initialization of fl6 below the AF_INET check, even if not strictly necessary.) Cc: Dave Jones <davej@redhat.com> Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | ipip: fix a regression in ioctlCong Wang2013-07-021-5/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a regression introduced by commit fd58156e456d9f68fe0448 (IPIP: Use ip-tunneling code.) Similar to GRE tunnel, previously we only check the parameters for SIOCADDTUNNEL and SIOCCHGTUNNEL, after that commit, the check is moved for all commands. So, just check for SIOCADDTUNNEL and SIOCCHGTUNNEL. Also, the check for i_key, o_key etc. is suspicious too, which did not exist before, reset them before passing to ip_tunnel_ioctl(). Cc: Pravin B Shelar <pshelar@nicira.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Cong Wang <amwang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | vti: remove duplicated code to fix a memory leakCong Wang2013-07-021-7/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | vti module allocates dev->tstats twice: in vti_fb_tunnel_init() and in vti_tunnel_init(), this lead to a memory leak of dev->tstats. Just remove the duplicated operations in vti_fb_tunnel_init(). (candidate for -stable) Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: Saurabh Mohan <saurabh.mohan@vyatta.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Cong Wang <amwang@redhat.com> Acked-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | gre: fix a regression in ioctlCong Wang2013-07-021-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When testing GRE tunnel, I got: # ip tunnel show get tunnel gre0 failed: Invalid argument get tunnel gre1 failed: Invalid argument This is a regression introduced by commit c54419321455631079c7d ("GRE: Refactor GRE tunneling code.") because previously we only check the parameters for SIOCADDTUNNEL and SIOCCHGTUNNEL, after that commit, the check is moved for all commands. So, just check for SIOCADDTUNNEL and SIOCCHGTUNNEL. After this patch I got: # ip tunnel show gre0: gre/ip remote any local any ttl inherit nopmtudisc gre1: gre/ip remote 192.168.122.101 local 192.168.122.45 ttl inherit Cc: Pravin B Shelar <pshelar@nicira.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Cong Wang <amwang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | ipv4: use next hop exceptions also for input routesTimo Teräs2013-06-292-16/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit d2d68ba9 (ipv4: Cache input routes in fib_info nexthops) assmued that "locally destined, and routed packets, never trigger PMTU events or redirects that will be processed by us". However, it seems that tunnel devices do trigger PMTU events in certain cases. At least ip_gre, ip6_gre, sit, and ipip do use the inner flow's skb_dst(skb)->ops->update_pmtu to propage mtu information from the outer flows. These can cause the inner flow mtu to be decreased. If next hop exceptions are not consulted for pmtu, IP fragmentation will not be done properly for these routes. It also seems that we really need to have the PMTU information always for netfilter TCPMSS clamp-to-pmtu feature to work properly. So for the time being, cache separate copies of input routes for each next hop exception. Signed-off-by: Timo Teräs <timo.teras@iki.fi> Reviewed-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | netlink: fix splat in skb_clone with large messagesPablo Neira2013-06-281-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since (c05cdb1 netlink: allow large data transfers from user-space), netlink splats if it invokes skb_clone on large netlink skbs since: * skb_shared_info was not correctly initialized. * skb->destructor is not set in the cloned skb. This was spotted by trinity: [ 894.990671] BUG: unable to handle kernel paging request at ffffc9000047b001 [ 894.991034] IP: [<ffffffff81a212c4>] skb_clone+0x24/0xc0 [...] [ 894.991034] Call Trace: [ 894.991034] [<ffffffff81ad299a>] nl_fib_input+0x6a/0x240 [ 894.991034] [<ffffffff81c3b7e6>] ? _raw_read_unlock+0x26/0x40 [ 894.991034] [<ffffffff81a5f189>] netlink_unicast+0x169/0x1e0 [ 894.991034] [<ffffffff81a601e1>] netlink_sendmsg+0x251/0x3d0 Fix it by: 1) introducing a new netlink_skb_clone function that is used in nl_fib_input, that sets our special skb->destructor in the cloned skb. Moreover, handle the release of the large cloned skb head area in the destructor path. 2) not allowing large skbuffs in the netlink broadcast path. I cannot find any reasonable use of the large data transfer using netlink in that path, moreover this helps to skip extra skb_clone handling. I found two more netlink clients that are cloning the skbs, but they are not in the sendmsg path. Therefore, the sole client cloning that I found seems to be the fib frontend. Thanks to Eric Dumazet for helping to address this issue. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | sit: add support of x-netnsNicolas Dichtel2013-06-281-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch allows to switch the netns when packet is encapsulated or decapsulated. In other word, the encapsulated packet is received in a netns, where the lookup is done to find the tunnel. Once the tunnel is found, the packet is decapsulated and injecting into the corresponding interface which stands to another netns. When one of the two netns is removed, the tunnel is destroyed. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | sit: fix 4in4 + IPsec scenarioNicolas Dichtel2013-06-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit 32b8a8e59c9c "sit: add IPv4 over IPv4 support", tunnel->parms.iph.protocol is 0 when both 4in4 and 6in4 are setup, but xfrm_lookup() is called only when proto is != 0, thus we need to pass the real value. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | inet: frag , remove an empty ifdef.Rami Rosen2013-06-201-2/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch removes an empty ifdef from inet_frag_intern() in net/ipv4/inet_fragment.c. commit b67bfe0d42cac56c512dd5da4b1b347a23f4b70a (hlist: drop the node parameter from iterators) removed hlist from net/ipv4/inet_fragment.c, but did not remove the enclosing ifdef command, which is now empty. Signed-off-by: Rami Rosen <ramirose@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | tcp: introduce a per-route knob for quick ackCong Wang2013-06-202-3/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In previous discussions, I tried to find some reasonable heuristics for delayed ACK, however this seems not possible, according to Eric: "ACKS might also be delayed because of bidirectional traffic, and is more controlled by the application response time. TCP stack can not easily estimate it." "ACK can be incredibly useful to recover from losses in a short time. The vast majority of TCP sessions are small lived, and we send one ACK per received segment anyway at beginning or retransmits to let the sender smoothly increase its cwnd, so an auto-tuning facility wont help them that much." and according to David: "ACKs are the only information we have to detect loss. And, for the same reasons that TCP VEGAS is fundamentally broken, we cannot measure the pipe or some other receiver-side-visible piece of information to determine when it's "safe" to stretch ACK. And even if it's "safe", we should not do it so that losses are accurately detected and we don't spuriously retransmit. The only way to know when the bandwidth increases is to "test" it, by sending more and more packets until drops happen. That's why all successful congestion control algorithms must operate on explicited tested pieces of information. Similarly, it's not really possible to universally know if it's safe to stretch ACK or not." It still makes sense to enable or disable quick ack mode like what TCP_QUICK_ACK does. Similar to TCP_QUICK_ACK option, but for people who can't modify the source code and still wants to control TCP delayed ACK behavior. As David suggested, this should belong to per-path scope, since different pathes may want different behaviors. Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Rick Jones <rick.jones2@hp.com> Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Thomas Graf <tgraf@suug.ch> CC: David Laight <David.Laight@ACULAB.COM> Signed-off-by: Cong Wang <amwang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | tcp:typo unset should be unsentWeiping Pan2013-06-201-1/+1
| | | | | | | | | | | | | | | Signed-off-by: Weiping Pan <wpan@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | ip_tunnel: push generic protocol handling to ip_tunnel module.Pravin B Shelar2013-06-204-26/+47
| | | | | | | | | | | | | | | | | | | | | | | | Process skb tunnel header before sending packet to protocol handler. this allows code sharing between gre and ovs gre modules. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | ip_tunnels: extend iptunnel_xmit()Pravin B Shelar2013-06-203-30/+98
| | | | | | | | | | | | | | | | | | | | | | | | Refactor various ip tunnels xmit functions and extend iptunnel_xmit() so that there is more code sharing. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-07-12 07:56:11 +0200