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path: root/net/ipv4/tcp_ipv4.c
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2014-01-21tcp: delete redundant calls of tcp_mtup_init()Peter Pan(潘卫平)
As tcp_rcv_state_process() has already calls tcp_mtup_init() for non-fastopen sock, we can delete the redundant calls of tcp_mtup_init() in tcp_{v4,v6}_syn_recv_sock(). Signed-off-by: Weiping Pan <panweiping3@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-26ipv4: fix checkpatch error with foo * barWeilong Chen
Signed-off-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06net: Remove FLOWI_FLAG_CAN_SLEEPSteffen Klassert
FLOWI_FLAG_CAN_SLEEP was used to notify xfrm about the posibility to sleep until the needed states are resolved. This code is gone, so FLOWI_FLAG_CAN_SLEEP is not needed anymore. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2013-11-29inet: fix possible seqlock deadlocksEric Dumazet
In commit c9e9042994d3 ("ipv4: fix possible seqlock deadlock") I left another places where IP_INC_STATS_BH() were improperly used. udp_sendmsg(), ping_v4_sendmsg() and tcp_v4_connect() are called from process context, not from softirq context. This was detected by lockdep seqlock support. Reported-by: jongman heo <jongman.heo@samsung.com> Fixes: 584bdf8cbdf6 ("[IPV4]: Fix "ipOutNoRoutes" counter error for TCP and UDP") Fixes: c319b4d76b9e ("net: ipv4: add IPPROTO_ICMP socket kind") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-15seq_file: remove "%n" usage from seq_file usersTetsuo Handa
All seq_printf() users are using "%n" for calculating padding size, convert them to use seq_setwidth() / seq_pad() pair. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Joe Perches <joe@perches.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-05ipv4: introduce new IP_MTU_DISCOVER mode IP_PMTUDISC_INTERFACEHannes Frederic Sowa
Sockets marked with IP_PMTUDISC_INTERFACE won't do path mtu discovery, their sockets won't accept and install new path mtu information and they will always use the interface mtu for outgoing packets. It is guaranteed that the packet is not fragmented locally. But we won't set the DF-Flag on the outgoing frames. Florian Weimer had the idea to use this flag to ensure DNS servers are never generating outgoing fragments. They may well be fragmented on the path, but the server never stores or usees path mtu values, which could well be forged in an attack. (The root of the problem with path MTU discovery is that there is no reliable way to authenticate ICMP Fragmentation Needed But DF Set messages because they are sent from intermediate routers with their source addresses, and the IMCP payload will not always contain sufficient information to identify a flow.) Recent research in the DNS community showed that it is possible to implement an attack where DNS cache poisoning is feasible by spoofing fragments. This work was done by Amir Herzberg and Haya Shulman: <https://sites.google.com/site/hayashulman/files/fragmentation-poisoning.pdf> This issue was previously discussed among the DNS community, e.g. <http://www.ietf.org/mail-archive/web/dnsext/current/msg01204.html>, without leading to fixes. This patch depends on the patch "ipv4: fix DO and PROBE pmtu mode regarding local fragmentation with UFO/CORK" for the enforcement of the non-fragmentable checks. If other users than ip_append_page/data should use this semantic too, we have to add a new flag to IPCB(skb)->flags to suppress local fragmentation and check for this in ip_finish_output. Many thanks to Florian Weimer for the idea and feedback while implementing this patch. Cc: David S. Miller <davem@davemloft.net> Suggested-by: Florian Weimer <fweimer@redhat.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-21tcp_memcontrol: Remove the per netns control.Eric W. Biederman
The code that is implemented is per memory cgroup not per netns, and having per netns bits is just confusing. Remove the per netns bits to make it easier to see what is really going on. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-10inet: includes a sock_common in request_sockEric Dumazet
TCP listener refactoring, part 5 : We want to be able to insert request sockets (SYN_RECV) into main ehash table instead of the per listener hash table to allow RCU lookups and remove listener lock contention. This patch includes the needed struct sock_common in front of struct request_sock This means there is no more inet6_request_sock IPv6 specific structure. Following inet_request_sock fields were renamed as they became macros to reference fields from struct sock_common. Prefix ir_ was chosen to avoid name collisions. loc_port -> ir_loc_port loc_addr -> ir_loc_addr rmt_addr -> ir_rmt_addr rmt_port -> ir_rmt_port iif -> ir_iif Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-08tcp/dccp: remove twchainEric Dumazet
TCP listener refactoring, part 3 : Our goal is to hash SYN_RECV sockets into main ehash for fast lookup, and parallel SYN processing. Current inet_ehash_bucket contains two chains, one for ESTABLISH (and friend states) sockets, another for TIME_WAIT sockets only. As the hash table is sized to get at most one socket per bucket, it makes little sense to have separate twchain, as it makes the lookup slightly more complicated, and doubles hash table memory usage. If we make sure all socket types have the lookup keys at the same offsets, we can use a generic and faster lookup. It turns out TIME_WAIT and ESTABLISHED sockets already have common lookup fields for IPv4. [ INET_TW_MATCH() is no longer needed ] I'll provide a follow-up to factorize IPv6 lookup as well, to remove INET6_TW_MATCH() This way, SYN_RECV pseudo sockets will be supported the same. A new sock_gen_put() helper is added, doing either a sock_put() or inet_twsk_put() [ and will support SYN_RECV later ]. Note this helper should only be called in real slow path, when rcu lookup found a socket that was moved to another identity (freed/reused immediately), but could eventually be used in other contexts, like sock_edemux() Before patch : dmesg | grep "TCP established" TCP established hash table entries: 524288 (order: 11, 8388608 bytes) After patch : TCP established hash table entries: 524288 (order: 10, 4194304 bytes) Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-02tcp: sndbuf autotuning improvementsEric Dumazet
tcp_fixup_sndbuf() is underestimating initial send buffer requirements. It was not noticed because big GSO packets were escaping the limitation, but with smaller TSO packets (or TSO/GSO/SG off), application hits sk_sndbuf before having a chance to fill enough packets in socket write queue. - initial cwnd can be bigger than 10 for specific routes - SKB_TRUESIZE() is a bit under real needs in some cases, because of power-of-two rounding in kmalloc() - Fast Recovery (RFC 5681 3.2) : Cubic needs 70% factor - Extra cushion (application might react slowly to POLLOUT) tcp_v4_conn_req_fastopen() needs to call tcp_init_metrics() before calling tcp_init_buffer_space() Then we realize tcp_new_space() should call tcp_fixup_sndbuf() instead of duplicating this stuff. Rename tcp_fixup_sndbuf() to tcp_sndbuf_expand() to be more descriptive. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Maciej Żenczykowski <maze@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04tcp: Change return value of tcp_rcv_established()Vijay Subramanian
tcp_rcv_established() returns only one value namely 0. We change the return value to void (as suggested by David Miller). After commit 0c24604b (tcp: implement RFC 5961 4.2), we no longer send RSTs in response to SYNs. We can remove the check and processing on the return value of tcp_rcv_established(). We also fix jtcp_rcv_established() in tcp_probe.c to match that of tcp_rcv_established(). Signed-off-by: Vijay Subramanian <subramanian.vijay@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-20tcp: trivial: Remove nocache argument from tcp_v4_send_synackChristoph Paasch
The nocache-argument was used in tcp_v4_send_synack as an argument to inet_csk_route_req. However, since ba3f7f04ef2b (ipv4: Kill FLOWI_FLAG_RT_NOCACHE and associated code.) this is no more used. This patch removes the unsued argument from tcp_v4_send_synack. Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-15net: proc_fs: trivial: print UIDs as unsigned intFrancesco Fusco
UIDs are printed in the proc_fs as signed int, whereas they are unsigned int. Signed-off-by: Francesco Fusco <ffusco@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-10tcp: add server ip to encrypt cookie in fast openYuchung Cheng
Encrypt the cookie with both server and client IPv4 addresses, such that multi-homed server will grant different cookies based on both the source and destination IPs. No client change is needed since cookie is opaque to the client. Signed-off-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-30tcp: add tcp_syncookies mode to allow unconditionally generation of syncookiesHannes Frederic Sowa
| 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>
2013-07-24tcp: TCP_NOTSENT_LOWAT socket optionEric Dumazet
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>
2013-07-22tcp: consolidate SYNACK RTT samplingYuchung Cheng
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>
2013-07-10net: rename ll methods to busy-pollEliezer Tamir
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>
2013-07-10net: rename include/net/ll_poll.h to include/net/busy_poll.hEliezer Tamir
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>
2013-07-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
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>
2013-06-19ipv4: Fixed MD5 key lookups when adding/ removing MD5 to/ from TCP sockets.Aydin Arik
MD5 key lookups on a given TCP socket were being performed incorrectly. This fix alters parameter inputs to the MD5 lookup function tcp_md5_do_lookup, which is called by functions tcp_md5_do_add and tcp_md5_do_del. Specifically, the change now inputs the correct address and address family required to make a proper lookup. Signed-off-by: Aydin Arik <aydin.arik@alliedtelesis.co.nz> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-10tcp: add low latency socket poll support.Eliezer Tamir
Adds low latency socket poll support for TCP. In tcp_v[46]_rcv() add a call to sk_mark_ll() to copy the napi_id from the skb to the sk. In tcp_recvmsg(), when there is no data in the socket we busy-poll. This is a good example of how to add busy-poll support to more protocols. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Tested-by: Willem de Bruijn <willemb@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>
2013-05-20tcp: md5: remove spinlock usage in fast pathEric Dumazet
TCP md5 code uses per cpu variables but protects access to them with a shared spinlock, which is a contention point. [ tcp_md5sig_pool_lock is locked twice per incoming packet ] Makes things much simpler, by allocating crypto structures once, first time a socket needs md5 keys, and not deallocating them as they are really small. Next step would be to allow crypto allocations being done in a NUMA aware way. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull VFS updates from Al Viro, Misc cleanups all over the place, mainly wrt /proc interfaces (switch create_proc_entry to proc_create(), get rid of the deprecated create_proc_read_entry() in favor of using proc_create_data() and seq_file etc). 7kloc removed. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits) don't bother with deferred freeing of fdtables proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h proc: Make the PROC_I() and PDE() macros internal to procfs proc: Supply a function to remove a proc entry by PDE take cgroup_open() and cpuset_open() to fs/proc/base.c ppc: Clean up scanlog ppc: Clean up rtas_flash driver somewhat hostap: proc: Use remove_proc_subtree() drm: proc: Use remove_proc_subtree() drm: proc: Use minor->index to label things, not PDE->name drm: Constify drm_proc_list[] zoran: Don't print proc_dir_entry data in debug reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show() proc: Supply an accessor for getting the data from a PDE's parent airo: Use remove_proc_subtree() rtl8192u: Don't need to save device proc dir PDE rtl8187se: Use a dir under /proc/net/r8180/ proc: Add proc_mkdir_data() proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h} proc: Move PDE_NET() to fs/proc/proc_net.c ...
2013-04-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c drivers/net/ethernet/emulex/benet/be.h include/net/tcp.h net/mac802154/mac802154.h Most conflicts were minor overlapping stuff. The be2net driver brought in some fixes that added __vlan_put_tag calls, which in net-next take an additional argument. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-29net: Add MIB counters for checksum errorsEric Dumazet
Add MIB counters for checksum errors in IP layer, and TCP/UDP/ICMP layers, to help diagnose problems. $ nstat -a | grep Csum IcmpInCsumErrors 72 0.0 TcpInCsumErrors 382 0.0 UdpInCsumErrors 463221 0.0 Icmp6InCsumErrors 75 0.0 Udp6InCsumErrors 173442 0.0 IpExtInCsumErrors 10884 0.0 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-09procfs: new helper - PDE_DATA(inode)Al Viro
The only part of proc_dir_entry the code outside of fs/proc really cares about is PDE(inode)->data. Provide a helper for that; static inline for now, eventually will be moved to fs/proc, along with the knowledge of struct proc_dir_entry layout. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Pull in the 'net' tree to get Daniel Borkmann's flow dissector infrastructure change. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-18tcp: dont handle MTU reduction on LISTEN socketEric Dumazet
When an ICMP ICMP_FRAG_NEEDED (or ICMPV6_PKT_TOOBIG) message finds a LISTEN socket, and this socket is currently owned by the user, we set TCP_MTU_REDUCED_DEFERRED flag in listener tsq_flags. This is bad because if we clone the parent before it had a chance to clear the flag, the child inherits the tsq_flags value, and next tcp_release_cb() on the child will decrement sk_refcnt. Result is that we might free a live TCP socket, as reported by Dormando. IPv4: Attempt to release TCP socket in state 1 Fix this issue by testing sk_state against TCP_LISTEN early, so that we set TCP_MTU_REDUCED_DEFERRED on appropriate sockets (not a LISTEN one) This bug was introduced in commit 563d34d05786 (tcp: dont drop MTU reduction indications) Reported-by: dormando <dormando@rydia.net> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-17tcp: Remove TCPCTChristoph Paasch
TCPCT uses option-number 253, reserved for experimental use and should not be used in production environments. Further, TCPCT does not fully implement RFC 6013. As a nice side-effect, removing TCPCT increases TCP's performance for very short flows: Doing an apache-benchmark with -c 100 -n 100000, sending HTTP-requests for files of 1KB size. before this patch: average (among 7 runs) of 20845.5 Requests/Second after: average (among 7 runs) of 21403.6 Requests/Second Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-12tcp: Tail loss probe (TLP)Nandita Dukkipati
This patch series implement the Tail loss probe (TLP) algorithm described in http://tools.ietf.org/html/draft-dukkipati-tcpm-tcp-loss-probe-01. The first patch implements the basic algorithm. TLP's goal is to reduce tail latency of short transactions. It achieves this by converting retransmission timeouts (RTOs) occuring due to tail losses (losses at end of transactions) into fast recovery. TLP transmits one packet in two round-trips when a connection is in Open state and isn't receiving any ACKs. The transmitted packet, aka loss probe, can be either new or a retransmission. When there is tail loss, the ACK from a loss probe triggers FACK/early-retransmit based fast recovery, thus avoiding a costly RTO. In the absence of loss, there is no change in the connection state. PTO stands for probe timeout. It is a timer event indicating that an ACK is overdue and triggers a loss probe packet. The PTO value is set to max(2*SRTT, 10ms) and is adjusted to account for delayed ACK timer when there is only one oustanding packet. TLP Algorithm On transmission of new data in Open state: -> packets_out > 1: schedule PTO in max(2*SRTT, 10ms). -> packets_out == 1: schedule PTO in max(2*RTT, 1.5*RTT + 200ms) -> PTO = min(PTO, RTO) Conditions for scheduling PTO: -> Connection is in Open state. -> Connection is either cwnd limited or no new data to send. -> Number of probes per tail loss episode is limited to one. -> Connection is SACK enabled. When PTO fires: new_segment_exists: -> transmit new segment. -> packets_out++. cwnd remains same. no_new_packet: -> retransmit the last segment. Its ACK triggers FACK or early retransmit based recovery. ACK path: -> rearm RTO at start of ACK processing. -> reschedule PTO if need be. In addition, the patch includes a small variation to the Early Retransmit (ER) algorithm, such that ER and TLP together can in principle recover any N-degree of tail loss through fast recovery. TLP is controlled by the same sysctl as ER, tcp_early_retrans sysctl. tcp_early_retrans==0; disables TLP and ER. ==1; enables RFC5827 ER. ==2; delayed ER. ==3; TLP and delayed ER. [DEFAULT] ==4; TLP only. The TLP patch series have been extensively tested on Google Web servers. It is most effective for short Web trasactions, where it reduced RTOs by 15% and improved HTTP response time (average by 6%, 99th percentile by 10%). The transmitted probes account for <0.5% of the overall transmissions. Signed-off-by: Nandita Dukkipati <nanditad@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-07tcp: uninline tcp_prequeue()Eric Dumazet
tcp_prequeue() became too big to be inlined. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-27hlist: drop the node parameter from iteratorsSasha Levin
I'm not sure why, but the hlist for each entry iterators were conceived list_for_each_entry(pos, head, member) The hlist ones were greedy and wanted an extra parameter: hlist_for_each_entry(tpos, pos, head, member) Why did they need an extra pos parameter? I'm not quite sure. Not only they don't really need it, it also prevents the iterator from looking exactly like the list iterator, which is unfortunate. Besides the semantic patch, there was some manual work required: - Fix up the actual hlist iterators in linux/list.h - Fix up the declaration of other iterators based on the hlist ones. - A very small amount of places were using the 'node' parameter, this was modified to use 'obj->member' instead. - Coccinelle didn't handle the hlist_for_each_entry_safe iterator properly, so those had to be fixed up manually. The semantic patch which is mostly the work of Peter Senna Tschudin is here: @@ iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host; type T; expression a,c,d,e; identifier b; statement S; @@ -T b; <+... when != b ( hlist_for_each_entry(a, - b, c, d) S | hlist_for_each_entry_continue(a, - b, c) S | hlist_for_each_entry_from(a, - b, c) S | hlist_for_each_entry_rcu(a, - b, c, d) S | hlist_for_each_entry_rcu_bh(a, - b, c, d) S | hlist_for_each_entry_continue_rcu_bh(a, - b, c) S | for_each_busy_worker(a, c, - b, d) S | ax25_uid_for_each(a, - b, c) S | ax25_for_each(a, - b, c) S | inet_bind_bucket_for_each(a, - b, c) S | sctp_for_each_hentry(a, - b, c) S | sk_for_each(a, - b, c) S | sk_for_each_rcu(a, - b, c) S | sk_for_each_from -(a, b) +(a) S + sk_for_each_from(a) S | sk_for_each_safe(a, - b, c, d) S | sk_for_each_bound(a, - b, c) S | hlist_for_each_entry_safe(a, - b, c, d, e) S | hlist_for_each_entry_continue_rcu(a, - b, c) S | nr_neigh_for_each(a, - b, c) S | nr_neigh_for_each_safe(a, - b, c, d) S | nr_node_for_each(a, - b, c) S | nr_node_for_each_safe(a, - b, c, d) S | - for_each_gfn_sp(a, c, d, b) S + for_each_gfn_sp(a, c, d) S | - for_each_gfn_indirect_valid_sp(a, c, d, b) S + for_each_gfn_indirect_valid_sp(a, c, d) S | for_each_host(a, - b, c) S | for_each_host_safe(a, - b, c, d) S | for_each_mesh_entry(a, - b, c, d) S ) ...+> [akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c] [akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c] [akpm@linux-foundation.org: checkpatch fixes] [akpm@linux-foundation.org: fix warnings] [akpm@linux-foudnation.org: redo intrusive kvm changes] Tested-by: Peter Senna Tschudin <peter.senna@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-18net: proc: change proc_net_remove to remove_proc_entryGao feng
proc_net_remove is only used to remove proc entries that under /proc/net,it's not a general function for removing proc entries of netns. if we want to remove some proc entries which under /proc/net/stat/, we still need to call remove_proc_entry. this patch use remove_proc_entry to replace proc_net_remove. we can remove proc_net_remove after this patch. Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-13tcp: send packets with a socket timestampAndrey Vagin
A socket timestamp is a sum of the global tcp_time_stamp and a per-socket offset. A socket offset is added in places where externally visible tcp timestamp option is parsed/initialized. Connections in the SYN_RECV state are not supported, global tcp_time_stamp is used for them, because repair mode doesn't support this state. In a future it can be implemented by the similar way as for TIME_WAIT sockets. Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrey Vagin <avagin@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/ethernet/intel/e1000e/ethtool.c drivers/net/vmxnet3/vmxnet3_drv.c drivers/net/wireless/iwlwifi/dvm/tx.c net/ipv6/route.c The ipv6 route.c conflict is simple, just ignore the 'net' side change as we fixed the same problem in 'net-next' by eliminating cached neighbours from ipv6 routes. The e1000e conflict is an addition of a new statistic in the ethtool code, trivial. The vmxnet3 conflict is about one change in 'net' removing a guarding conditional, whilst in 'net-next' we had a netdev_info() conversion. The iwlwifi conflict is dealing with a WARN_ON() conversion in 'net-next' vs. a revert happening in 'net'. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-04tcp: Update MIB counters for dropsVijay Subramanian
This patch updates LINUX_MIB_LISTENDROPS in tcp_v4_conn_request() and tcp_v4_err(). tcp_v4_conn_request() in particular can drop SYNs for various reasons which are not currently tracked. Signed-off-by: Vijay Subramanian <subramanian.vijay@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-29tcp: Increment LISTENOVERFLOW and LISTENDROPS in tcp_v4_conn_request()Nivedita Singhvi
We drop a connection request if the accept backlog is full and there are sufficient packets in the syn queue to warrant starting drops. Increment the appropriate counters so this isn't silent, for accurate stats and help in debugging. This patch assumes LINUX_MIB_LISTENDROPS is a superset of/includes the counter LINUX_MIB_LISTENOVERFLOWS. Signed-off-by: Nivedita Singhvi <niv@us.ibm.com> Acked-by: Vijay Subramanian <subramanian.vijay@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-29Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Bring in the 'net' tree so that we can get some ipv4/ipv6 bug fixes that some net-next work will build upon. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-23soreuseport: TCP/IPv4 implementationTom Herbert
Allow multiple listener sockets to bind to the same port. Motivation for soresuseport would be something like a web server binding to port 80 running with multiple threads, where each thread might have it's own listener socket. This could be done as an alternative to other models: 1) have one listener thread which dispatches completed connections to workers. 2) accept on a single listener socket from multiple threads. In case #1 the listener thread can easily become the bottleneck with high connection turn-over rate. In case #2, the proportion of connections accepted per thread tends to be uneven under high connection load (assuming simple event loop: while (1) { accept(); process() }, wakeup does not promote fairness among the sockets. We have seen the disproportion to be as high as 3:1 ratio between thread accepting most connections and the one accepting the fewest. With so_reusport the distribution is uniform. Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-20tcp: fix incorrect LOCKDROPPEDICMPS counterEric Dumazet
commit 563d34d057 (tcp: dont drop MTU reduction indications) added an error leading to incorrect accounting of LINUX_MIB_LOCKDROPPEDICMPS If socket is owned by the user, we want to increment this SNMP counter, unless the message is a (ICMP_DEST_UNREACH,ICMP_FRAG_NEEDED) one. Reported-by: Maciej Żenczykowski <maze@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Signed-off-by: Maciej Żenczykowski <maze@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-06tcp: make sysctl_tcp_ecn namespace awareHannes Frederic Sowa
As per suggestion from Eric Dumazet this patch makes tcp_ecn sysctl namespace aware. The reason behind this patch is to ease the testing of ecn problems on the internet and allows applications to tune their own use of ecn. Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Miller <davem@davemloft.net> Cc: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-14inet: Fix kmemleak in tcp_v4/6_syn_recv_sock and dccp_v4/6_request_recv_sockChristoph Paasch
If in either of the above functions inet_csk_route_child_sock() or __inet_inherit_port() fails, the newsk will not be freed: unreferenced object 0xffff88022e8a92c0 (size 1592): comm "softirq", pid 0, jiffies 4294946244 (age 726.160s) hex dump (first 32 bytes): 0a 01 01 01 0a 01 01 02 00 00 00 00 a7 cc 16 00 ................ 02 00 03 01 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff8153d190>] kmemleak_alloc+0x21/0x3e [<ffffffff810ab3e7>] kmem_cache_alloc+0xb5/0xc5 [<ffffffff8149b65b>] sk_prot_alloc.isra.53+0x2b/0xcd [<ffffffff8149b784>] sk_clone_lock+0x16/0x21e [<ffffffff814d711a>] inet_csk_clone_lock+0x10/0x7b [<ffffffff814ebbc3>] tcp_create_openreq_child+0x21/0x481 [<ffffffff814e8fa5>] tcp_v4_syn_recv_sock+0x3a/0x23b [<ffffffff814ec5ba>] tcp_check_req+0x29f/0x416 [<ffffffff814e8e10>] tcp_v4_do_rcv+0x161/0x2bc [<ffffffff814eb917>] tcp_v4_rcv+0x6c9/0x701 [<ffffffff814cea9f>] ip_local_deliver_finish+0x70/0xc4 [<ffffffff814cec20>] ip_local_deliver+0x4e/0x7f [<ffffffff814ce9f8>] ip_rcv_finish+0x1fc/0x233 [<ffffffff814cee68>] ip_rcv+0x217/0x267 [<ffffffff814a7bbe>] __netif_receive_skb+0x49e/0x553 [<ffffffff814a7cc3>] netif_receive_skb+0x50/0x82 This happens, because sk_clone_lock initializes sk_refcnt to 2, and thus a single sock_put() is not enough to free the memory. Additionally, things like xfrm, memcg, cookie_values,... may have been initialized. We have to free them properly. This is fixed by forcing a call to tcp_done(), ending up in inet_csk_destroy_sock, doing the final sock_put(). tcp_done() is necessary, because it ends up doing all the cleanup on xfrm, memcg, cookie_values, xfrm,... Before calling tcp_done, we have to set the socket to SOCK_DEAD, to force it entering inet_csk_destroy_sock. To avoid the warning in inet_csk_destroy_sock, inet_num has to be set to 0. As inet_csk_destroy_sock does a dec on orphan_count, we first have to increase it. Calling tcp_done() allows us to remove the calls to tcp_clear_xmit_timer() and tcp_cleanup_congestion_control(). A similar approach is taken for dccp by calling dccp_done(). This is in the kernel since 093d282321 (tproxy: fix hash locking issue when using port redirection in __inet_inherit_port()), thus since version >= 2.6.37. Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-22ipv6: adapt connect for repair moveAndrey Vagin
This is work the same as for ipv4. All other hacks about tcp repair are in common code for ipv4 and ipv6, so this patch is enough for repairing ipv6 connections. Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrey Vagin <avagin@openvz.org> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c Minor conflict between the BCM_CNIC define removal in net-next and a bug fix added to net. Based upon a conflict resolution patch posted by Stephen Rothwell. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-03tcp: better retrans tracking for defer-acceptEric Dumazet
For passive TCP connections using TCP_DEFER_ACCEPT facility, we incorrectly increment req->retrans each time timeout triggers while no SYNACK is sent. SYNACK are not sent for TCP_DEFER_ACCEPT that were established (for which we received the ACK from client). Only the last SYNACK is sent so that we can receive again an ACK from client, to move the req into accept queue. We plan to change this later to avoid the useless retransmit (and potential problem as this SYNACK could be lost) TCP_INFO later gives wrong information to user, claiming imaginary retransmits. Decouple req->retrans field into two independent fields : num_retrans : number of retransmit num_timeout : number of timeouts num_timeout is the counter that is incremented at each timeout, regardless of actual SYNACK being sent or not, and used to compute the exponential timeout. Introduce inet_rtx_syn_ack() helper to increment num_retrans only if ->rtx_syn_ack() succeeded. Use inet_rtx_syn_ack() from tcp_check_req() to increment num_retrans when we re-send a SYNACK in answer to a (retransmitted) SYN. Prior to this patch, we were not counting these retransmits. Change tcp_v[46]_rtx_synack() to increment TCP_MIB_RETRANSSEGS only if a synack packet was successfully queued. Reported-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Julian Anastasov <ja@ssi.bg> Cc: Vijay Subramanian <subramanian.vijay@gmail.com> Cc: Elliott Hughes <enh@google.com> Cc: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-31tcp: make tcp_clear_md5_list staticstephen hemminger
Trivial. Only used in one file. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-23ipv4: tcp: clean up tcp_v4_early_demux()Eric Dumazet
Use same header helpers than tcp_v6_early_demux() because they are a bit faster, and as they make IPv4/IPv6 versions look the same. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-22tcp: add SYN/data info to TCP_INFOYuchung Cheng
Add a bit TCPI_OPT_SYN_DATA (32) to the socket option TCP_INFO:tcpi_options. It's set if the data in SYN (sent or received) is acked by SYN-ACK. Server or client application can use this information to check Fast Open success rate. 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>