tcp/dccp: remove icsk->icsk_ack.timeout

icsk->icsk_ack.timeout can be replaced by icsk->csk_delack_timer.expires

This saves 8 bytes in TCP/DCCP sockets and helps for better cache locality.

Signed-

tcp/dccp: remove icsk->icsk_ack.timeout

icsk->icsk_ack.timeout can be replaced by icsk->csk_delack_timer.expires

This saves 8 bytes in TCP/DCCP sockets and helps for better cache locality.

Signed-off-by: Eric Dumazet <[email protected]>
Reviewed-by: Kuniyuki Iwashima <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

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tcp/dccp: remove icsk->icsk_timeout

icsk->icsk_timeout can be replaced by icsk->icsk_retransmit_timer.expires

This saves 8 bytes in TCP/DCCP sockets and helps for better cache locality.

Signed-off

tcp/dccp: remove icsk->icsk_timeout

icsk->icsk_timeout can be replaced by icsk->icsk_retransmit_timer.expires

This saves 8 bytes in TCP/DCCP sockets and helps for better cache locality.

Signed-off-by: Eric Dumazet <[email protected]>
Reviewed-by: Kuniyuki Iwashima <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

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tcp: record last received ipv6 flowlabel

In order to better estimate whether a data packet has been
retransmitted or is the result of a TLP, we save the last received
ipv6 flowlabel.

To make space

tcp: record last received ipv6 flowlabel

In order to better estimate whether a data packet has been
retransmitted or is the result of a TLP, we save the last received
ipv6 flowlabel.

To make space for this field we resize the "ato" field in
inet_connection_sock as the current value of TCP_DELACK_MAX can be
fully contained in 8 bits and add a compile_time_assert ensuring this
field is the required size.

v2: addressed kernel bot feedback about dccp_delack_timer()
v3: addressed build error introduced by commit bbf80d713fe7 ("tcp:
derive delack_max from rto_min")

Signed-off-by: David Morley <[email protected]>
Signed-off-by: Neal Cardwell <[email protected]>
Signed-off-by: Yuchung Cheng <[email protected]>
Tested-by: David Morley <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Signed-off-by: Paolo Abeni <[email protected]>

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dccp: annotate lockless accesses to sk->sk_err_soft

This field can be read/written without lock synchronization.

Signed-off-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <da

dccp: annotate lockless accesses to sk->sk_err_soft

This field can be read/written without lock synchronization.

Signed-off-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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net: sock: introduce sk_error_report

This patch introduces a function wrapper to call the sk_error_report
callback. That will prepare to add additional handling whenever
sk_error_report is called, f

net: sock: introduce sk_error_report

This patch introduces a function wrapper to call the sk_error_report
callback. That will prepare to add additional handling whenever
sk_error_report is called, for example to trace socket errors.

Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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net: dccp: convert tasklets to use new tasklet_setup() API

In preparation for unconditionally passing the
struct tasklet_struct pointer to all tasklet
callbacks, switch to using the new tasklet_setu

net: dccp: convert tasklets to use new tasklet_setup() API

In preparation for unconditionally passing the
struct tasklet_struct pointer to all tasklet
callbacks, switch to using the new tasklet_setup()
and from_tasklet() to pass the tasklet pointer explicitly.

Signed-off-by: Romain Perier <[email protected]>
Signed-off-by: Allen Pais <[email protected]>
Signed-off-by: Jakub Kicinski <[email protected]>

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inet: remove icsk_ack.blocked

TCP has been using it to work around the possibility of tcp_delack_timer()
finding the socket owned by user.

After commit 6f458dfb4092 ("tcp: improve latencies of time

inet: remove icsk_ack.blocked

TCP has been using it to work around the possibility of tcp_delack_timer()
finding the socket owned by user.

After commit 6f458dfb4092 ("tcp: improve latencies of timer triggered events")
we added TCP_DELACK_TIMER_DEFERRED atomic bit for more immediate recovery,
so we can get rid of icsk_ack.blocked

This frees space that following patch will reuse.

Signed-off-by: Eric Dumazet <[email protected]>
Acked-by: Soheil Hassas Yeganeh <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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net: dccp: delete repeated words

Drop duplicated words in /net/dccp/.

Signed-off-by: Randy Dunlap <[email protected]>
Cc: Gerrit Renker <[email protected]>
Cc: [email protected]
Cc: "Dav

net: dccp: delete repeated words

Drop duplicated words in /net/dccp/.

Signed-off-by: Randy Dunlap <[email protected]>
Cc: Gerrit Renker <[email protected]>
Cc: [email protected]
Cc: "David S. Miller" <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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net: dccp: kerneldoc fixes

Simple fixes which require no deep knowledge of the code.

Cc: Gerrit Renker <[email protected]>
Signed-off-by: Andrew Lunn <[email protected]>
Signed-off-by: David S. Mi

net: dccp: kerneldoc fixes

Simple fixes which require no deep knowledge of the code.

Cc: Gerrit Renker <[email protected]>
Signed-off-by: Andrew Lunn <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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tcp: Refactor pingpong code

Instead of using pingpong as a single bit information, we refactor the
code to treat it as a counter. When interactive session is detected,
we set pingpong count to TCP_P

tcp: Refactor pingpong code

Instead of using pingpong as a single bit information, we refactor the
code to treat it as a counter. When interactive session is detected,
we set pingpong count to TCP_PINGPONG_THRESH. And when pingpong count
is >= TCP_PINGPONG_THRESH, we consider the session in pingpong mode.

This patch is a pure refactor and sets foundation for the next patch.
This patch itself does not change any pingpong logic.

Signed-off-by: Wei Wang <[email protected]>
Signed-off-by: Yuchung Cheng <[email protected]>
Signed-off-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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dccp: fix tasklet usage

syzbot reported a crash in tasklet_action_common() caused by dccp.

dccp needs to make sure socket wont disappear before tasklet handler
has completed.

This patch takes a re

dccp: fix tasklet usage

syzbot reported a crash in tasklet_action_common() caused by dccp.

dccp needs to make sure socket wont disappear before tasklet handler
has completed.

This patch takes a reference on the socket when arming the tasklet,
and moves the sock_put() from dccp_write_xmit_timer() to dccp_write_xmitlet()

kernel BUG at kernel/softirq.c:514!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
(ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.17.0-rc3+ #30
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:tasklet_action_common.isra.19+0x6db/0x700 kernel/softirq.c:515
RSP: 0018:ffff8801d9b3faf8 EFLAGS: 00010246
dccp_close: ABORT with 65423 bytes unread
RAX: 1ffff1003b367f6b RBX: ffff8801daf1f3f0 RCX: 0000000000000000
RDX: ffff8801cf895498 RSI: 0000000000000004 RDI: 0000000000000000
RBP: ffff8801d9b3fc40 R08: ffffed0039f12a95 R09: ffffed0039f12a94
dccp_close: ABORT with 65423 bytes unread
R10: ffffed0039f12a94 R11: ffff8801cf8954a3 R12: 0000000000000000
R13: ffff8801d9b3fc18 R14: dffffc0000000000 R15: ffff8801cf895490
FS: 0000000000000000(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2bc28000 CR3: 00000001a08a9000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
tasklet_action+0x1d/0x20 kernel/softirq.c:533
__do_softirq+0x2e0/0xaf5 kernel/softirq.c:285
dccp_close: ABORT with 65423 bytes unread
run_ksoftirqd+0x86/0x100 kernel/softirq.c:646
smpboot_thread_fn+0x417/0x870 kernel/smpboot.c:164
kthread+0x345/0x410 kernel/kthread.c:238
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
Code: 48 8b 85 e8 fe ff ff 48 8b 95 f0 fe ff ff e9 94 fb ff ff 48 89 95 f0 fe ff ff e8 81 53 6e 00 48 8b 95 f0 fe ff ff e9 62 fb ff ff <0f> 0b 48 89 cf 48 89 8d e8 fe ff ff e8 64 53 6e 00 48 8b 8d e8
RIP: tasklet_action_common.isra.19+0x6db/0x700 kernel/softirq.c:515 RSP: ffff8801d9b3faf8

Fixes: dc841e30eaea ("dccp: Extend CCID packet dequeueing interface")
Signed-off-by: Eric Dumazet <[email protected]>
Reported-by: syzbot <[email protected]>
Cc: Gerrit Renker <[email protected]>
Cc: [email protected]
Signed-off-by: David S. Miller <[email protected]>

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net: dccp: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()

net: dccp: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly. Adds a pointer back to the sock.

Cc: Gerrit Renker <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Soheil Hassas Yeganeh <[email protected]>
Cc: Hannes Frederic Sowa <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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inet/connection_sock: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and f

inet/connection_sock: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: "David S. Miller" <[email protected]>
Cc: Gerrit Renker <[email protected]>
Cc: Alexey Kuznetsov <[email protected]>
Cc: Hideaki YOSHIFUJI <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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net: rename NET_{ADD|INC}_STATS_BH()

Rename NET_INC_STATS_BH() to __NET_INC_STATS()
and NET_ADD_STATS_BH() to __NET_ADD_STATS()

Signed-off-by: Eric Dumazet <[email protected]>
Signed-off-by: Davi

net: rename NET_{ADD|INC}_STATS_BH()

Rename NET_INC_STATS_BH() to __NET_INC_STATS()
and NET_ADD_STATS_BH() to __NET_ADD_STATS()

Signed-off-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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dccp: rename DCCP_INC_STATS_BH()

Rename DCCP_INC_STATS_BH() to __DCCP_INC_STATS()

Signed-off-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

inet: get rid of central tcp/dccp listener timer

One of the major issue for TCP is the SYNACK rtx handling,
done by inet_csk_reqsk_queue_prune(), fired by the keepalive
timer of a TCP_LISTEN socket.

inet: get rid of central tcp/dccp listener timer

One of the major issue for TCP is the SYNACK rtx handling,
done by inet_csk_reqsk_queue_prune(), fired by the keepalive
timer of a TCP_LISTEN socket.

This function runs for awful long times, with socket lock held,
meaning that other cpus needing this lock have to spin for hundred of ms.

SYNACK are sent in huge bursts, likely to cause severe drops anyway.

This model was OK 15 years ago when memory was very tight.

We now can afford to have a timer per request sock.

Timer invocations no longer need to lock the listener,
and can be run from all cpus in parallel.

With following patch increasing somaxconn width to 32 bits,
I tested a listener with more than 4 million active request sockets,
and a steady SYNFLOOD of ~200,000 SYN per second.
Host was sending ~830,000 SYNACK per second.

This is ~100 times more what we could achieve before this patch.

Later, we will get rid of the listener hash and use ehash instead.

Signed-off-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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net/dccp/timer.c: use 'u64' instead of 's64' to avoid compiler's warning

'dccp_timestamp_seed' is initialized once by ktime_get_real() in
dccp_timestamping_init(). It is always less than ktime_get_r

net/dccp/timer.c: use 'u64' instead of 's64' to avoid compiler's warning

'dccp_timestamp_seed' is initialized once by ktime_get_real() in
dccp_timestamping_init(). It is always less than ktime_get_real()
in dccp_timestamp().

Then, ktime_us_delta() in dccp_timestamp() will always return positive
number. So can use manual type cast to let compiler and do_div() know
about it to avoid warning.

The related warning (with allmodconfig under unicore32):

CC [M] net/dccp/timer.o
net/dccp/timer.c: In function ‘dccp_timestamp’:
net/dccp/timer.c:285: warning: comparison of distinct pointer types lacks a cast

Signed-off-by: Chen Gang <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules

These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things

net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules

These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things won't break when we remove the implicit presence
of module.h from everywhere.

Signed-off-by: Paul Gortmaker <[email protected]>

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dccp: Refine the wait-for-ccid mechanism

This extends the existing wait-for-ccid routine so that it may be used with
different types of CCID, addressing the following problems:

1) The queue-drain

dccp: Refine the wait-for-ccid mechanism

This extends the existing wait-for-ccid routine so that it may be used with
different types of CCID, addressing the following problems:

1) The queue-drain mechanism only works with rate-based CCIDs. If CCID-2 for
example has a full TX queue and becomes network-limited just as the
application wants to close, then waiting for CCID-2 to become unblocked
could lead to an indefinite delay (i.e., application "hangs").
2) Since each TX CCID in turn uses a feedback mechanism, there may be changes
in its sending policy while the queue is being drained. This can lead to
further delays during which the application will not be able to terminate.
3) The minimum wait time for CCID-3/4 can be expected to be the queue length
times the current inter-packet delay. For example if tx_qlen=100 and a delay
of 15 ms is used for each packet, then the application would have to wait
for a minimum of 1.5 seconds before being allowed to exit.
4) There is no way for the user/application to control this behaviour. It would
be good to use the timeout argument of dccp_close() as an upper bound. Then
the maximum time that an application is willing to wait for its CCIDs to can
be set via the SO_LINGER option.

These problems are addressed by giving the CCID a grace period of up to the
`timeout' value.

The wait-for-ccid function is, as before, used when the application
(a) has read all the data in its receive buffer and
(b) if SO_LINGER was set with a non-zero linger time, or
(c) the socket is either in the OPEN (active close) or in the PASSIVE_CLOSEREQ
state (client application closes after receiving CloseReq).

In addition, there is a catch-all case of __skb_queue_purge() after waiting for
the CCID. This is necessary since the write queue may still have data when
(a) the host has been passively-closed,
(b) abnormal termination (unread data, zero linger time),
(c) wait-for-ccid could not finish within the given time limit.

Signed-off-by: Gerrit Renker <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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dccp: Extend CCID packet dequeueing interface

This extends the packet dequeuing interface of dccp_write_xmit() to allow
1. CCIDs to take care of timing when the next packet may be sent;
2. delayed

dccp: Extend CCID packet dequeueing interface

This extends the packet dequeuing interface of dccp_write_xmit() to allow
1. CCIDs to take care of timing when the next packet may be sent;
2. delayed sending (as before, with an inter-packet gap up to 65.535 seconds).

The main purpose is to take CCID-2 out of its polling mode (when it is network-
limited, it tries every millisecond to send, without interruption).

The mode of operation for (2) is as follows:
* new packet is enqueued via dccp_sendmsg() => dccp_write_xmit(),
* ccid_hc_tx_send_packet() detects that it may not send (e.g. window full),
* it signals this condition via `CCID_PACKET_WILL_DEQUEUE_LATER',
* dccp_write_xmit() returns without further action;
* after some time the wait-condition for CCID becomes true,
* that CCID schedules the tasklet,
* tasklet function calls ccid_hc_tx_send_packet() via dccp_write_xmit(),
* since the wait-condition is now true, ccid_hc_tx_packet() returns "send now",
* packet is sent, and possibly more (since dccp_write_xmit() loops).

Code reuse: the taskled function calls dccp_write_xmit(), the timer function
reduces to a wrapper around the same code.

Signed-off-by: Gerrit Renker <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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net: sk_dst_cache RCUification

With latest CONFIG_PROVE_RCU stuff, I felt more comfortable to make this
work.

sk->sk_dst_cache is currently protected by a rwlock (sk_dst_lock)

This rwlock is readl

net: sk_dst_cache RCUification

With latest CONFIG_PROVE_RCU stuff, I felt more comfortable to make this
work.

sk->sk_dst_cache is currently protected by a rwlock (sk_dst_lock)

This rwlock is readlocked for a very small amount of time, and dst
entries are already freed after RCU grace period. This calls for RCU
again :)

This patch converts sk_dst_lock to a spinlock, and use RCU for readers.

__sk_dst_get() is supposed to be called with rcu_read_lock() or if
socket locked by user, so use appropriate rcu_dereference_check()
condition (rcu_read_lock_held() || sock_owned_by_user(sk))

This patch avoids two atomic ops per tx packet on UDP connected sockets,
for example, and permits sk_dst_lock to be much less dirtied.

Signed-off-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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net: Fix for dst_negative_advice

dst_negative_advice() should check for changed dst and reset
sk_tx_queue_mapping accordingly. Pass sock to the callers of
dst_negative_advice.

(sk_reset_txq is defi

net: Fix for dst_negative_advice

dst_negative_advice() should check for changed dst and reset
sk_tx_queue_mapping accordingly. Pass sock to the callers of
dst_negative_advice.

(sk_reset_txq is defined just for use by dst_negative_advice. The
only way I could find to get around this is to move dst_negative_()
from dst.h to dst.c, include sock.h in dst.c, etc)

Signed-off-by: Krishna Kumar <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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dccp: Limit feature negotiation to connection setup phase

This patch limits feature (capability) negotation to the connection setup phase:

1. Although it is theoretically possible to perform featu

dccp: Limit feature negotiation to connection setup phase

This patch limits feature (capability) negotation to the connection setup phase:

1. Although it is theoretically possible to perform feature negotiation at any
time (and RFC 4340 supports this), in practice this is prohibitively complex,
as it requires to put traffic on hold for each new negotiation.
2. As a byproduct of restricting feature negotiation to connection setup, the
feature-negotiation retransmit timer is no longer required. This part is now
mapped onto the protocol-level retransmission.
Details indicating why timers are no longer needed can be found on
http://www.erg.abdn.ac.uk/users/gerrit/dccp/notes/feature_negotiation/\
implementation_notes.html

This patch disables anytime negotiation, subsequent patches work out full
feature negotiation support for connection setup.

Signed-off-by: Gerrit Renker <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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This reverts "Merge branch 'dccp' of git://eden-feed.erg.abdn.ac.uk/dccp_exp"
as it accentally contained the wrong set of patches. These will be
submitted separately.
Signed-off-by: Gerrit Renker <ge

This reverts "Merge branch 'dccp' of git://eden-feed.erg.abdn.ac.uk/dccp_exp"
as it accentally contained the wrong set of patches. These will be
submitted separately.
Signed-off-by: Gerrit Renker <[email protected]>

show more ...