tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2// Fastopen server zerocopy test:
3//
4// send data with MSG_FASTOPEN | MSG_ZEROCOPY and verify that the
5// kernel returns the notification ID.
6
7`./defaults.sh
8 ./set_sysctls.py /proc/sys/net/ipv4/tcp_fastopen=0x207`
9
10// Set up a TFO server listening socket.
11 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
12 +.1 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
13 +0 bind(3, ..., ...) = 0
14 +0 listen(3, 1) = 0
15 +0 setsockopt(3, SOL_TCP, TCP_FASTOPEN, [2], 4) = 0
16 +0 setsockopt(3, SOL_SOCKET, SO_ZEROCOPY, [1], 4) = 0
17
18// Client sends a SYN with data.
19 +.1 < S 0:1000(1000) win 32792 <mss 1460,sackOK,nop,nop>
20 +0 > S. 0:0(0) ack 1001 <mss 1460,nop,nop,sackOK>
21
22// Server accepts and replies with data.
23+.005 accept(3, ..., ...) = 4
24 +0 read(4, ..., 1024) = 1000
25 +0 sendto(4, ..., 1000, MSG_ZEROCOPY, ..., ...) = 1000
26 +0 > P. 1:1001(1000) ack 1001
27 +.05 < . 1001:1001(0) ack 1001 win 32792
28
29// Read from error queue: now has first zerocopy notification
30 +0.1 recvmsg(4, {msg_name(...)=...,
31 msg_iov(1)=[{...,0}],
32 msg_flags=MSG_ERRQUEUE,
33 msg_control=[
34 {cmsg_level=CMSG_LEVEL_IP,
35 cmsg_type=CMSG_TYPE_RECVERR,
36 cmsg_data={ee_errno=0,
37 ee_origin=SO_EE_ORIGIN_ZEROCOPY,
38 ee_type=0,
39 ee_code=SO_EE_CODE_ZEROCOPY_COPIED,
40 ee_info=0,
41 ee_data=0}}
42 ]}, MSG_ERRQUEUE) = 0
43
44`/tmp/sysctl_restore_${PPID}.sh`