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path: root/include/net/tcp.h
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2006-06-17[TCP]: Minimum congestion window consolidation.Stephen Hemminger
Many of the TCP congestion methods all just use ssthresh as the minimum congestion window on decrease. Rather than duplicating the code, just have that be the default if that handle in the ops structure is not set. Minor behaviour change to TCP compound. It probably wants to use this (ssthresh) as lower bound, rather than ssthresh/2 because the latter causes undershoot on loss. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17[I/OAT]: Add a sysctl for tuning the I/OAT offloaded I/O thresholdChris Leech
Any socket recv of less than this ammount will not be offloaded Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17[I/OAT]: Rename cleanup_rbuf to tcp_cleanup_rbuf and make non-staticChris Leech
Needed to be able to call tcp_cleanup_rbuf in tcp_input.c for I/OAT Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17[I/OAT]: Structure changes for TCP recv offload to I/OATChris Leech
Adds an async_wait_queue and some additional fields to tcp_sock, and a dma_cookie_t to sk_buff. Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-31[TCP]: Kill unused extern decl for tcp_v4_hash_connecting()David S. Miller
Noticed by Alan Menegotto. Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[NET]: {get|set}sockopt compatibility layerDmitry Mishin
This patch extends {get|set}sockopt compatibility layer in order to move protocol specific parts to their place and avoid huge universal net/compat.c file in the future. Signed-off-by: Dmitry Mishin <dim@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[TCP]: sysctl to allow TCP window > 32767 sans wscaleRick Jones
Back in the dark ages, we had to be conservative and only allow 15-bit window fields if the window scale option was not negotiated. Some ancient stacks used a signed 16-bit quantity for the window field of the TCP header and would get confused. Those days are long gone, so we can use the full 16-bits by default now. There is a sysctl added so that we can still interact with such old stacks Signed-off-by: Rick Jones <rick.jones2@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[TCP]: MTU probingJohn Heffner
Implementation of packetization layer path mtu discovery for TCP, based on the internet-draft currently found at <http://www.ietf.org/internet-drafts/draft-ietf-pmtud-method-05.txt>. Signed-off-by: John Heffner <jheffner@psc.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[TCP]: less inline'sStephen Hemminger
TCP inline usage cleanup: * get rid of inline in several places * replace __inline__ with inline where possible * move functions used in one file out of tcp.h * let compiler decide on used once cases On x86_64: text data bss dec hex filename 3594701 648348 567400 4810449 4966d1 vmlinux.orig 3593133 648580 567400 4809113 496199 vmlinux On sparc64: text data bss dec hex filename 2538278 406152 530392 3474822 350586 vmlinux.ORIG 2536382 406384 530392 3473158 34ff06 vmlinux Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[TCP]: Don't use __constant_htonl for a non const argArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[TWSK]: Introduce struct timewait_sock_opsArnaldo Carvalho de Melo
So that we can share several timewait sockets related functions and make the timewait mini sockets infrastructure closer to the request mini sockets one. Next changesets will take advantage of this, moving more code out of TCP and DCCP v4 and v6 to common infrastructure. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[ICSK]: Rename struct tcp_func to struct inet_connection_sock_af_opsArnaldo Carvalho de Melo
And move it to struct inet_connection_sock. DCCP will use it in the upcoming changesets. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-15[TCP]: More spelling fixes.Stephen Hemminger
From Joe Perches Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-10[TCP]: speed up SACK processingStephen Hemminger
Use "hints" to speed up the SACK processing. Various forms of this have been used by TCP developers (Web100, STCP, BIC) to avoid the 2x linear search of outstanding segments. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-10[TCP]: spelling fixesStephen Hemminger
Minor spelling fixes for TCP code. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-10[TCP]: Appropriate Byte Count supportStephen Hemminger
This is an updated version of the RFC3465 ABC patch originally for Linux 2.6.11-rc4 by Yee-Ting Li. ABC is a way of counting bytes ack'd rather than packets when updating congestion control. The orignal ABC described in the RFC applied to a Reno style algorithm. For advanced congestion control there is little change after leaving slow start. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-10[TCP]: add tcp_slow_start helperStephen Hemminger
Move all the code that does linear TCP slowstart to one inline function to ease later patch to add ABC support. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-10[TCP]: fix congestion window update when using TSO deferalStephen Hemminger
TCP peformance with TSO over networks with delay is awful. On a 100Mbit link with 150ms delay, we get 4Mbits/sec with TSO and 50Mbits/sec without TSO. The problem is with TSO, we intentionally do not keep the maximum number of packets in flight to fill the window, we hold out to until we can send a MSS chunk. But, we also don't update the congestion window unless we have filled, as per RFC2861. This patch replaces the check for the congestion window being full with something smarter that accounts for TSO. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-10[NET]: Detect hardware rx checksum faults correctlyHerbert Xu
Here is the patch that introduces the generic skb_checksum_complete which also checks for hardware RX checksum faults. If that happens, it'll call netdev_rx_csum_fault which currently prints out a stack trace with the device name. In future it can turn off RX checksum. I've converted every spot under net/ that does RX checksum checks to use skb_checksum_complete or __skb_checksum_complete with the exceptions of: * Those places where checksums are done bit by bit. These will call netdev_rx_csum_fault directly. * The following have not been completely checked/converted: ipmr ip_vs netfilter dccp This patch is based on patches and suggestions from Stephen Hemminger and David S. Miller. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-10-08[PATCH] gfp flags annotations - part 1Al Viro
- added typedef unsigned int __nocast gfp_t; - replaced __nocast uses for gfp flags with gfp_t - it gives exactly the same warnings as far as sparse is concerned, doesn't change generated code (from gcc point of view we replaced unsigned int with typedef) and documents what's going on far better. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-01[TCP]: Keep TSO enabled even during loss events.David S. Miller
All we need to do is resegment the queue so that we record SACK information accurately. The edges of the SACK blocks guide our resegmenting decisions. With help from Herbert Xu. Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NET]: Fix sparse warningsArnaldo Carvalho de Melo
Of this type, mostly: CHECK net/ipv6/netfilter.c net/ipv6/netfilter.c:96:12: warning: symbol 'ipv6_netfilter_init' was not declared. Should it be static? net/ipv6/netfilter.c:101:6: warning: symbol 'ipv6_netfilter_fini' was not declared. Should it be static? Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET_DIAG]: Move the tcp_diag interface to the proper placeArnaldo Carvalho de Melo
With this the previous setup is back, i.e. tcp_diag can be built as a module, as dccp_diag and both share the infrastructure available in inet_diag. If one selects CONFIG_INET_DIAG as module CONFIG_INET_TCP_DIAG will also be built as a module, as will CONFIG_INET_DCCP_DIAG, if CONFIG_IP_DCCP was selected static or as a module, if CONFIG_INET_DIAG is y, being statically linked CONFIG_INET_TCP_DIAG will follow suit and CONFIG_INET_DCCP_DIAG will be built in the same manner as CONFIG_IP_DCCP. Now to aim at UDP, converting it to use inet_hashinfo, so that we can use iproute2 for UDP sockets as well. Ah, just to show an example of this new infrastructure working for DCCP :-) [root@qemu ~]# ./ss -dane State Recv-Q Send-Q Local Address:Port Peer Address:Port LISTEN 0 0 *:5001 *:* ino:942 sk:cfd503a0 ESTAB 0 0 127.0.0.1:5001 127.0.0.1:32770 ino:943 sk:cfd50a60 ESTAB 0 0 127.0.0.1:32770 127.0.0.1:5001 ino:947 sk:cfd50700 TIME-WAIT 0 0 127.0.0.1:32769 127.0.0.1:5001 timer:(timewait,3.430ms,0) ino:0 sk:cf209620 Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[TCPDIAG]: Just rename everything to inet_diagArnaldo Carvalho de Melo
Next changeset will rename tcp_diag.[ch] to inet_diag.[ch]. I'm taking this longer route so as to easy review, making clear the changes made all along the way. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[ICSK]: Move TCP congestion avoidance members to icskArnaldo Carvalho de Melo
This changeset basically moves tcp_sk()->{ca_ops,ca_state,etc} to inet_csk(), minimal renaming/moving done in this changeset to ease review. Most of it is just changes of struct tcp_sock * to struct sock * parameters. With this we move to a state closer to two interesting goals: 1. Generalisation of net/ipv4/tcp_diag.c, becoming inet_diag.c, being used for any INET transport protocol that has struct inet_hashinfo and are derived from struct inet_connection_sock. Keeps the userspace API, that will just not display DCCP sockets, while newer versions of tools can support DCCP. 2. INET generic transport pluggable Congestion Avoidance infrastructure, using the current TCP CA infrastructure with DCCP. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[TIMEWAIT]: Move inet_timewait_death_row routines to ↵Arnaldo Carvalho de Melo
net/ipv4/inet_timewait_sock.c Also export the ones that will be used in the next changeset, when DCCP uses this infrastructure. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[TIMEWAIT]: Introduce inet_timewait_death_rowArnaldo Carvalho de Melo
That groups all of the tables and variables associated to the TCP timewait schedulling/recycling/killing code, that now can be isolated from the TCP specific code and used by other transport protocols, such as DCCP. Next changeset will move this code to net/ipv4/inet_timewait_sock.c Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[ICSK]: Move generalised functions from tcp to inet_connection_sockArnaldo Carvalho de Melo
This also improves reqsk_queue_prune and renames it to inet_csk_reqsk_queue_prune, as it deals with both inet_connection_sock and inet_request_sock objects, not just with request_sock ones thus belonging to inet_request_sock. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[ICSK]: Introduce reqsk_queue_prune from code in tcp_synack_timerArnaldo Carvalho de Melo
With this we're very close to getting all of the current TCP refactorings in my dccp-2.6 tree merged, next changeset will export some functions needed by the current DCCP code and then dccp-2.6.git will be born! Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[ICSK]: Generalise tcp_listen_{start,stop}Arnaldo Carvalho de Melo
This also moved inet_iif from tcp to inet_hashtables.h, as it is needed by the inet_lookup callers, perhaps this needs a bit of polishing, but for now seems fine. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NET]: Just move the inet_connection_sock function from tcp sourcesArnaldo Carvalho de Melo
Completing the previous changeset, this also generalises tcp_v4_synq_add, renaming it to inet_csk_reqsk_queue_hash_add, already geing used in the DCCP tree, which I plan to merge RSN. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NET]: Introduce inet_connection_sockArnaldo Carvalho de Melo
This creates struct inet_connection_sock, moving members out of struct tcp_sock that are shareable with other INET connection oriented protocols, such as DCCP, that in my private tree already uses most of these members. The functions that operate on these members were renamed, using a inet_csk_ prefix while not being moved yet to a new file, so as to ease the review of these changes. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Generalise tcp_tw_bucket, aka TIME_WAIT socketsArnaldo Carvalho de Melo
This paves the way to generalise the rest of the sock ID lookup routines and saves some bytes in TCPv4 TIME_WAIT sockets on distro kernels (where IPv6 is always built as a module): [root@qemu ~]# grep tw_sock /proc/slabinfo tw_sock_TCPv6 0 0 128 31 1 tw_sock_TCP 0 0 96 41 1 [root@qemu ~]# Now if a protocol wants to use the TIME_WAIT generic infrastructure it only has to set the sk_prot->twsk_obj_size field with the size of its inet_timewait_sock derived sock and proto_register will create sk_prot->twsk_slab, for now its only for INET sockets, but we can introduce timewait_sock later if some non INET transport protocolo wants to use this stuff. Next changesets will take advantage of this new infrastructure to generalise even more TCP code. [acme@toy net-2.6.14]$ grep built-in /tmp/before.size /tmp/after.size /tmp/before.size: 188646 11764 5068 205478 322a6 net/ipv4/built-in.o /tmp/after.size: 188144 11764 5068 204976 320b0 net/ipv4/built-in.o [acme@toy net-2.6.14]$ Tested with both IPv4 & IPv6 (::1 (localhost) & ::ffff:172.20.0.1 (qemu host)). Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[TCP]: Move the tcp sock states to net/tcp_states.hArnaldo Carvalho de Melo
Lots of places just needs the states, not even linux/tcp.h, where this enum was, needs it. This speeds up development of the refactorings as less sources are rebuilt when things get moved from net/tcp.h. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Generalise the tcp_listen_ lock routinesArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Move tcp_port_rover to inet_hashinfoArnaldo Carvalho de Melo
Also expose all of the tcp_hashinfo members, i.e. killing those tcp_ehash, etc macros, this will more clearly expose already generic functions and some that need just a bit of work to become generic, as we'll see in the upcoming changesets. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Generalise tcp_bind_hash & tcp_inherit_portArnaldo Carvalho de Melo
This required moving tcp_bucket_cachep to inet_hashinfo. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Move bind_hash from tcp_sk to inet_skArnaldo Carvalho de Melo
This should really be in a inet_connection_sock, but I'm leaving it for a later optimization, when some more fields common to INET transport protocols now in tcp_sk or inet_sk will be chunked out into inet_connection_sock, for now its better to concentrate on getting the changes in the core merged to leave the DCCP tree with only DCCP specific code. Next changesets will take advantage of this move to generalise things like tcp_bind_hash, tcp_put_port, tcp_inherit_port, making the later receive a inet_hashinfo parameter, and even __tcp_tw_hashdance, etc in the future, when tcp_tw_bucket gets transformed into the struct timewait_sock hierarchy. tcp_destroy_sock also is eligible as soon as tcp_orphan_count gets moved to sk_prot. A cascade of incremental changes will ultimately make the tcp_lookup functions be fully generic. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Move the TCP hashtable functions/structs to inet_hashtables.[ch]Arnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Just rename the TCP hashtable functions/structs to inet_Arnaldo Carvalho de Melo
This is to break down the complexity of the series of patches, making it very clear that this one just does: 1. renames tcp_ prefixed hashtable functions and data structures that were already mostly generic to inet_ to share it with DCCP and other INET transport protocols. 2. Removes not used functions (__tb_head & tb_head) 3. Removes some leftover prototypes in the headers (tcp_bucket_unlock & tcp_v4_build_header) Next changesets will move tcp_sk(sk)->bind_hash to inet_sock so that we can make functions such as tcp_inherit_port, __tcp_inherit_port, tcp_v4_get_port, __tcp_put_port, generic and get others like tcp_destroy_sock closer to generic (tcp_orphan_count will go to sk->sk_prot to allow this). Eventually most of these functions will be used passing the transport protocol inet_hashinfo structure. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[INET]: Introduce inet_sk_rebuild_headerArnaldo Carvalho de Melo
From tcp_v4_rebuild_header, that already was pretty generic, I only needed to use sk->sk_protocol instead of the hardcoded IPPROTO_TCP and establish the requirement that INET transport layer protocols that want to use this function map TCP_SYN_SENT to its equivalent state. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[SOCK]: Introduce sk_setup_capsArnaldo Carvalho de Melo
From tcp_v4_setup_caps, that always is preceded by a call to __sk_dst_set, so coalesce this sequence into sk_setup_caps, removing one call to a TCP function in the IP layer. Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29[NET]: Cleanup INET_REFCNT_DEBUG codeArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-30[NET]: Spelling mistakes threshoulds -> thresholdsBaruch Even
Just simple spelling mistake fixes. Signed-Off-By: Baruch Even <baruch@ev-en.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-08[NET]: Fix sparse warningsVictor Fusco
From: Victor Fusco <victor@cetuc.puc-rio.br> Fix the sparse warning "implicit cast to nocast type" Signed-off-by: Victor Fusco <victor@cetuc.puc-rio.br> Signed-off-by: Domen Puncer <domen@coderock.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-08[NET]: Transform skb_queue_len() binary tests into skb_queue_empty()David S. Miller
This is part of the grand scheme to eliminate the qlen member of skb_queue_head, and subsequently remove the 'list' member of sk_buff. Most users of skb_queue_len() want to know if the queue is empty or not, and that's trivially done with skb_queue_empty() which doesn't use the skb_queue_head->qlen member and instead uses the queue list emptyness as the test. Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05[TCP]: Move to new TSO segmenting scheme.David S. Miller
Make TSO segment transmit size decisions at send time not earlier. The basic scheme is that we try to build as large a TSO frame as possible when pulling in the user data, but the size of the TSO frame output to the card is determined at transmit time. This is guided by tp->xmit_size_goal. It is always set to a multiple of MSS and tells sendmsg/sendpage how large an SKB to try and build. Later, tcp_write_xmit() and tcp_push_one() chop up the packet if necessary and conditions warrant. These routines can also decide to "defer" in order to wait for more ACKs to arrive and thus allow larger TSO frames to be emitted. A general observation is that TSO elongates the pipe, thus requiring a larger congestion window and larger buffering especially at the sender side. Therefore, it is important that applications 1) get a large enough socket send buffer (this is accomplished by our dynamic send buffer expansion code) 2) do large enough writes. Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05[TCP]: Fix __tcp_push_pending_frames() 'nonagle' handling.David S. Miller
'nonagle' should be passed to the tcp_snd_test() function as 'TCP_NAGLE_PUSH' if we are checking an SKB not at the tail of the write_queue. This is because Nagle does not apply to such frames since we cannot possibly tack more data onto them. However, while doing this __tcp_push_pending_frames() makes all of the packets in the write_queue use this modified 'nonagle' value. Fix the bug and simplify this function by just calling tcp_write_xmit() directly if sk_send_head is non-NULL. As a result, we can now make tcp_data_snd_check() just call tcp_push_pending_frames() instead of the specialized __tcp_data_snd_check(). Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05[TCP]: Fix redundant calculations of tcp_current_mss()David S. Miller
tcp_write_xmit() uses tcp_current_mss(), but some of it's callers, namely __tcp_push_pending_frames(), already has this value available already. While we're here, fix the "cur_mss" argument to be "unsigned int" instead of plain "unsigned". Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05[TCP]: Kill extra cwnd validate in __tcp_push_pending_frames().David S. Miller
The tcp_cwnd_validate() function should only be invoked if we actually send some frames, yet __tcp_push_pending_frames() will always invoke it. tcp_write_xmit() does the call for us, so the call here can simply be removed. Also, tcp_write_xmit() can be marked static. Signed-off-by: David S. Miller <davem@davemloft.net>