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* [TCP]: Clear stale pred_flags when snd_wnd changesHerbert Xu2005-10-271-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This bug is responsible for causing the infamous "Treason uncloaked" messages that's been popping up everywhere since the printk was added. It has usually been blamed on foreign operating systems. However, some of those reports implicate Linux as both systems are running Linux or the TCP connection is going across the loopback interface. In fact, there really is a bug in the Linux TCP header prediction code that's been there since at least 2.1.8. This bug was tracked down with help from Dale Blount. The effect of this bug ranges from harmless "Treason uncloaked" messages to hung/aborted TCP connections. The details of the bug and fix is as follows. When snd_wnd is updated, we only update pred_flags if tcp_fast_path_check succeeds. When it fails (for example, when our rcvbuf is used up), we will leave pred_flags with an out-of-date snd_wnd value. When the out-of-date pred_flags happens to match the next incoming packet we will again hit the fast path and use the current snd_wnd which will be wrong. In the case of the treason messages, it just happens that the snd_wnd cached in pred_flags is zero while tp->snd_wnd is non-zero. Therefore when a zero-window packet comes in we incorrectly conclude that the window is non-zero. In fact if the peer continues to send us zero-window pure ACKs we will continue making the same mistake. It's only when the peer transmits a zero-window packet with data attached that we get a chance to snap out of it. This is what triggers the treason message at the next retransmit timeout. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
* [TCP]: Don't over-clamp window in tcp_clamp_window()Alexey Kuznetsov2005-09-291-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | From: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Handle better the case where the sender sends full sized frames initially, then moves to a mode where it trickles out small amounts of data at a time. This known problem is even mentioned in the comments above tcp_grow_window() in tcp_input.c, specifically: ... * The scheme does not work when sender sends good segments opening * window and then starts to feed us spagetti. But it should work * in common situations. Otherwise, we have to rely on queue collapsing. ... When the sender gives full sized frames, the "struct sk_buff" overhead from each packet is small. So we'll advertize a larger window. If the sender moves to a mode where small segments are sent, this ratio becomes tilted to the other extreme and we start overrunning the socket buffer space. tcp_clamp_window() tries to address this, but it's clamping of tp->window_clamp is a wee bit too aggressive for this particular case. Fix confirmed by Ion Badulescu. Signed-off-by: David S. Miller <davem@davemloft.net>
* [TCP]: Compute in_sacked properly when we split up a TSO frame.Herbert Xu2005-09-141-7/+9
| | | | | | | | | | | | | The problem is that the SACK fragmenting code may incorrectly call tcp_fragment() with a length larger than the skb->len. This happens when the skb on the transmit queue completely falls to the LHS of the SACK. And add a BUG() check to tcp_fragment() so we can spot this kind of error more quickly in the future. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TCP]: Keep TSO enabled even during loss events.David S. Miller2005-09-011-12/+24
| | | | | | | | | | 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>
* [NET]: Fix sparse warningsArnaldo Carvalho de Melo2005-08-291-1/+1
| | | | | | | | | | | 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>
* [NET]: Store skb->timestamp as offset to a base timestampPatrick McHardy2005-08-291-3/+7
| | | | | | | Reduces skb size by 8 bytes on 64-bit. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* [ICSK]: Move TCP congestion avoidance members to icskArnaldo Carvalho de Melo2005-08-291-99/+124
| | | | | | | | | | | | | | | | | | | | | 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>
* [ICSK]: Introduce reqsk_queue_prune from code in tcp_synack_timerArnaldo Carvalho de Melo2005-08-291-3/+8
| | | | | | | | | | 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>
* [NET]: Just move the inet_connection_sock function from tcp sourcesArnaldo Carvalho de Melo2005-08-291-4/+6
| | | | | | | | | 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>
* [NET]: Introduce inet_connection_sockArnaldo Carvalho de Melo2005-08-291-128/+138
| | | | | | | | | | | | | | 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>
* [NET]: Kill skb->listDavid S. Miller2005-08-291-13/+16
| | | | | | | | | | | | | | Remove the "list" member of struct sk_buff, as it is entirely redundant. All SKB list removal callers know which list the SKB is on, so storing this in sk_buff does nothing other than taking up some space. Two tricky bits were SCTP, which I took care of, and two ATM drivers which Francois Romieu <romieu@fr.zoreil.com> fixed up. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
* [NET]: Transform skb_queue_len() binary tests into skb_queue_empty()David S. Miller2005-07-081-6/+5
| | | | | | | | | | | | | 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>
* [TCP]: Move to new TSO segmenting scheme.David S. Miller2005-07-051-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* [TCP]: Break out send buffer expansion test.David S. Miller2005-07-051-4/+23
| | | | | | | This makes it easier to understand, and allows easier tweaking of the heuristic later on. Signed-off-by: David S. Miller <davem@davemloft.net>
* [TCP]: Do not call tcp_tso_acked() if no work to do.David S. Miller2005-07-051-1/+2
| | | | | | | In tcp_clean_rtx_queue(), if the TSO packet is not even partially acked, do not waste time calling tcp_tso_acked(). Signed-off-by: David S. Miller <davem@davemloft.net>
* [TCP]: Kill bogus comment above tcp_tso_acked().David S. Miller2005-07-051-9/+0
| | | | | | | | Everything stated there is out of data. tcp_trim_skb() does adjust the available socket send buffer space and skb->truesize now. Signed-off-by: David S. Miller <davem@davemloft.net>
* [TCP]: Fix __tcp_push_pending_frames() 'nonagle' handling.David S. Miller2005-07-051-10/+7
| | | | | | | | | | | | | | | | | | | | | '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>
* [TCP]: Move __tcp_data_snd_check into tcp_output.cDavid S. Miller2005-07-051-10/+0
| | | | | | | | It reimplements portions of tcp_snd_check(), so it we move it to tcp_output.c we can consolidate it's logic much easier in a later change. Signed-off-by: David S. Miller <davem@davemloft.net>
* [TCP]: Add pluggable congestion control algorithm infrastructure.Stephen Hemminger2005-06-231-684/+53
| | | | | | | | | | Allow TCP to have multiple pluggable congestion control algorithms. Algorithms are defined by a set of operations and can be built in or modules. The legacy "new RENO" algorithm is used as a starting point and fallback. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [TCP]: Fix stretch ACK performance killer when doing ucopy.David S. Miller2005-05-231-10/+1
| | | | | | | | | | | | | | | | When we are doing ucopy, we try to defer the ACK generation to cleanup_rbuf(). This works most of the time very well, but if the ucopy prequeue is large, this ACKing behavior kills performance. With TSO, it is possible to fill the prequeue so large that by the time the ACK is sent and gets back to the sender, most of the window has emptied of data and performance suffers significantly. This behavior does help in some cases, so we should think about re-enabling this trick in the future, using some kind of limit in order to avoid the bug case. Signed-off-by: David S. Miller <davem@davemloft.net>
* [PATCH] update Ross Biro bouncing email addressJesper Juhl2005-05-051-1/+1
| | | | | | | | | Ross moved. Remove the bad email address so people will find the correct one in ./CREDITS. Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [TCP]: Trivial tcp_data_queue() cleanupJames Morris2005-04-251-1/+0
| | | | | | | | This patch removes a superfluous intialization from tcp_data_queue(). Signed-off-by: James Morris <jmorris@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Linux-2.6.12-rc2Linus Torvalds2005-04-161-0/+4959
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!