Commit eab35989 authored by Soham Chakradeo's avatar Soham Chakradeo Committed by Jakub Kicinski
Browse files

selftests/net: packetdrill: import tcp/fast_recovery, tcp/nagle, tcp/timestamping 



Use the standard import and testing method, as described in the
import of tcp/ecn , tcp/close , tcp/sack , tcp/tcp_info.

Signed-off-by: default avatarWillem de Bruijn <willemb@google.com>
Signed-off-by: default avatarSoham Chakradeo <sohamch@google.com>
Link: https://patch.msgid.link/20241217185203.297935-3-sohamch.kernel@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 88395c07

tools/testing/selftests/net/packetdrill/tcp_fast_recovery_prr-ss-10pkt-lost-1.pkt

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// SPDX-License-Identifier: GPL-2.0

// Test PRR-slowstart implementation.

// In this variant we test a simple case where in-flight == ssthresh

// all the way through recovery, so during fast recovery we send one segment

// for each segment SACKed/ACKed.



// Set up config.

`./defaults.sh`



// Establish a connection.

    0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3

   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0

   +0 bind(3, ..., ...) = 0

   +0 listen(3, 1) = 0



  +.1 < S 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 7>

   +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8>

// RTT 100ms

  +.1 < . 1:1(0) ack 1 win 320

   +0 accept(3, ..., ...) = 4



// Send 10 data segments.

   +0 write(4, ..., 10000) = 10000

   +0 > P. 1:10001(10000) ack 1



// Lost packet 1:1001.

 +.11 < . 1:1(0) ack 1 win 320 <sack 1001:2001,nop,nop>

 +.01 < . 1:1(0) ack 1 win 320 <sack 1001:3001,nop,nop>

 +.01 < . 1:1(0) ack 1 win 320 <sack 1001:4001,nop,nop>

// Enter fast recovery.

   +0 > . 1:1001(1000) ack 1

 +.01 %{

assert tcpi_ca_state == TCP_CA_Recovery, tcpi_ca_state

assert tcpi_snd_cwnd == 7, tcpi_snd_cwnd

assert tcpi_snd_ssthresh == 7, tcpi_snd_ssthresh

}%



// Write some more, which we will send 1 MSS at a time,

// as in-flight segments are SACKed or ACKed.

 +.01 write(4, ..., 7000) = 7000



 +.01 < . 1:1(0) ack 1 win 320 <sack 1001:5001,nop,nop>

   +0 > . 10001:11001(1000) ack 1



 +.01 < . 1:1(0) ack 1 win 320 <sack 1001:6001,nop,nop>

   +0 > . 11001:12001(1000) ack 1



 +.01 < . 1:1(0) ack 1 win 320 <sack 1001:7001,nop,nop>

   +0 > . 12001:13001(1000) ack 1



 +.01 < . 1:1(0) ack 1 win 320 <sack 1001:8001,nop,nop>

   +0 > . 13001:14001(1000) ack 1



 +.01 < . 1:1(0) ack 1 win 320 <sack 1001:9001,nop,nop>

   +0 > . 14001:15001(1000) ack 1



 +.01 < . 1:1(0) ack 1 win 320 <sack 1001:10001,nop,nop>

   +0 > . 15001:16001(1000) ack 1



 +.02 < . 1:1(0) ack 10001 win 320

   +0 > P. 16001:17001(1000) ack 1

// Leave fast recovery.

 +.01 %{

assert tcpi_ca_state == TCP_CA_Open, tcpi_ca_state

assert tcpi_snd_cwnd == 7, tcpi_snd_cwnd

assert tcpi_snd_ssthresh == 7, tcpi_snd_ssthresh

}%



 +.03 < . 1:1(0) ack 12001 win 320

 +.02 < . 1:1(0) ack 14001 win 320

 +.02 < . 1:1(0) ack 16001 win 320

 +.02 < . 1:1(0) ack 17001 win 320

tools/testing/selftests/net/packetdrill/tcp_fast_recovery_prr-ss-30pkt-lost-1_4-11_16.pkt

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// SPDX-License-Identifier: GPL-2.0

// Test PRR-slowstart implementation. The sender sends 20 packets. Packet

// 1 to 4, and 11 to 16 are dropped.

`./defaults.sh`



// Establish a connection.

    0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3

   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0

   +0 bind(3, ..., ...) = 0

   +0 listen(3, 1) = 0



   +0 < S 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 7>

   +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8>



 +.01 < . 1:1(0) ack 1 win 320

   +0 accept(3, ..., ...) = 4



// Write 20 data segments.

   +0 write(4, ..., 20000) = 20000

   +0 > P. 1:10001(10000) ack 1



// Receive first DUPACK, entering PRR part

 +.01 < . 1:1(0) ack 1 win 320 <sack 4001:5001,nop,nop>

   +0 > . 10001:11001(1000) ack 1

+.002 < . 1:1(0) ack 1 win 320 <sack 4001:6001,nop,nop>

   +0 > . 11001:12001(1000) ack 1

+.002 < . 1:1(0) ack 1 win 320 <sack 4001:7001,nop,nop>

   +0 > . 1:1001(1000) ack 1

+.002 < . 1:1(0) ack 1 win 320 <sack 4001:8001,nop,nop>

   +0 > . 1001:2001(1000) ack 1

+.002 < . 1:1(0) ack 1 win 320 <sack 4001:9001,nop,nop>

   +0 > . 2001:3001(1000) ack 1

+.002 < . 1:1(0) ack 1 win 320 <sack 4001:10001,nop,nop>

   +0 > . 3001:4001(1000) ack 1

// Enter PRR CRB

+.002 < . 1:1(0) ack 1 win 320 <sack 4001:11001,nop,nop>

   +0 > . 12001:13001(1000) ack 1

+.002 < . 1:1(0) ack 1 win 320 <sack 4001:12001,nop,nop>

   +0 > . 13001:14001(1000) ack 1

// Enter PRR slow start

 +.01 < . 1:1(0) ack 1001 win 320 <sack 4001:12001,nop,nop>

   +0 > P. 14001:16001(2000) ack 1

+.002 < . 1:1(0) ack 1001 win 320 <sack 2001:12001,nop,nop>

   +0 > . 1001:2001(1000) ack 1

   +0 > . 16001:17001(1000) ack 1

// inflight reaches ssthresh, goes into packet conservation mode

+.002 < . 1:1(0) ack 1001 win 320 <sack 2001:13001,nop,nop>

   +0 > . 17001:18001(1000) ack 1

+.002 < . 1:1(0) ack 1001 win 320 <sack 2001:14001,nop,nop>

   +0 > . 18001:19001(1000) ack 1

tools/testing/selftests/net/packetdrill/tcp_fast_recovery_prr-ss-30pkt-lost1_4.pkt

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// SPDX-License-Identifier: GPL-2.0

// Test PRR-slowstart implementation. The sender sends 20 packets. Packet

// 1 to 4 are lost. The sender writes another 10 packets.

`./defaults.sh`



// Establish a connection.

    0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3

   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0

   +0 bind(3, ..., ...) = 0

   +0 listen(3, 1) = 0



   +0 < S 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 7>

   +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8>



 +.01 < . 1:1(0) ack 1 win 320

   +0 accept(3, ..., ...) = 4



// Send 20 data segments.

   +0 write(4, ..., 10000) = 10000

   +0 > P. 1:10001(10000) ack 1



// Lost packet 1,2,3,4

 +.01 < . 1:1(0) ack 1 win 320 <sack 4001:5001,nop,nop>

+.002 < . 1:1(0) ack 1 win 320 <sack 4001:6001,nop,nop>

   +0 < . 1:1(0) ack 1 win 320 <sack 4001:7001,nop,nop>

   +0 > . 1:1001(1000) ack 1

   +0 < . 1:1(0) ack 1 win 320 <sack 4001:8001,nop,nop>

   +0 > . 1001:2001(1000) ack 1

   +0 < . 1:1(0) ack 1 win 320 <sack 4001:9001,nop,nop>

   +0 > . 2001:3001(1000) ack 1

   +0 < . 1:1(0) ack 1 win 320 <sack 4001:10001,nop,nop>

   +0 > . 3001:4001(1000) ack 1



// Receiver ACKs all data.

 +.01 < . 1:1(0) ack 1001 win 320 <sack 4001:10001,nop,nop>

   +0 < . 1:1(0) ack 2001 win 320 <sack 4001:10001,nop,nop>

   +0 < . 1:1(0) ack 3001 win 320 <sack 4001:10001,nop,nop>

   +0 < . 1:1(0) ack 10001 win 320



// Writes another 10 packets, which the ssthresh*mss amount

// should be sent right away

 +.01 write(4, ..., 10000) = 10000

   +0 > . 10001:17001(7000) ack 1

tools/testing/selftests/net/packetdrill/tcp_fast_recovery_prr-ss-ack-below-snd_una-cubic.pkt

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// SPDX-License-Identifier: GPL-2.0

// Test PRR-slowstart implementation.

// In this variant we verify that the sender uses SACK info on an ACK

// below snd_una.



// Set up config.

`./defaults.sh`



// Establish a connection.

    0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3

   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0

   +0 bind(3, ..., ...) = 0

   +0 listen(3, 1) = 0



   +0 < S 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 8>

   +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8>

// RTT 10ms

 +.01 < . 1:1(0) ack 1 win 320

   +0 accept(3, ..., ...) = 4



// Send 10 data segments.

   +0 write(4, ..., 10000) = 10000

   +0 > P. 1:10001(10000) ack 1



// Lost packet 1:1001,4001:5001,7001:8001.

 +.01 < . 1:1(0) ack 1 win 320 <sack 1001:2001,nop,nop>

   +0 < . 1:1(0) ack 1 win 320 <sack 1001:3001,nop,nop>

   +0 < . 1:1(0) ack 1 win 320 <sack 1001:3001 8001:9001,nop,nop>

   +0 > . 1:1001(1000) ack 1



+.012 < . 1:1(0) ack 4001 win 320 <sack 8001:9001,nop,nop>

   +0 > . 4001:7001(3000) ack 1



   +0 write(4, ..., 10000) = 10000



// The following ACK was reordered - delayed so that it arrives with

// an ACK field below snd_una. Here we check that the newly-SACKed

// 2MSS at 5001:7001 cause us to send out 2 more MSS.

+.002 < . 1:1(0) ack 3001 win 320 <sack 5001:7001,nop,nop>

   +0 > . 7001:8001(1000) ack 1

   +0 > . 10001:11001(1000) ack 1

tools/testing/selftests/net/packetdrill/tcp_nagle_https_client.pkt

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// SPDX-License-Identifier: GPL-2.0

// This is a test inspired by an Android client app using SSL. This

// test verifies using TCP_NODELAY would save application latency

// (Perhaps even better with TCP_NAGLE).

//

`./defaults.sh

ethtool -K tun0 tso off gso off

./set_sysctls.py /proc/sys/net/ipv4/tcp_timestamps=0`



    0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 4

   +0 fcntl(4, F_SETFL, O_RDWR|O_NONBLOCK) = 0

   +0 setsockopt(4, SOL_TCP, TCP_NODELAY, [1], 4) = 0



   +0 connect(4, ..., ...) = -1 EINPROGRESS (Operation now in progress)

   +0 > S 0:0(0) <mss 1460,nop,nop,sackOK,nop,wscale 8>

  +.1 < S. 0:0(0) ack 1 win 5792 <mss 974,nop,nop,sackOK,nop,wscale 7>

   +0 > . 1:1(0) ack 1



// SSL handshake (resumed session)

   +0 write(4, ..., 517) = 517

   +0 > P. 1:518(517) ack 1

  +.1 < . 1:1(0) ack 518 win 229



   +0 < P. 1:144(143) ack 1 win 229

   +0 > . 518:518(0) ack 144

   +0 read(4, ..., 1000) = 143



// Application POST header (51B) and body (2002B)

   +0 write(4, ..., 51) = 51

   +0 > P. 518:569(51) ack 144

 +.03 write(4, ..., 2002) = 2002

   +0 > . 569:1543(974) ack 144

   +0 > P. 1543:2517(974) ack 144

// Without disabling Nagle, this packet will not happen until the remote ACK.

   +0 > P. 2517:2571(54) ack 144



  +.1 < . 1:1(0) ack 2571 win 229



// Reset sysctls

`/tmp/sysctl_restore_${PPID}.sh`