| // SPDX-License-Identifier: GPL-2.0 |
| // Test for blocking write. |
| --tolerance_usecs=10000 |
| |
| `./defaults.sh |
| ./set_sysctls.py /proc/sys/net/ipv4/tcp_min_tso_segs=10 |
| ` |
| |
| // 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 50000 <mss 1000,nop,wscale 0> |
| +0 > S. 0:0(0) ack 1 <mss 1460,nop,wscale 8> |
| +.1 < . 1:1(0) ack 1 win 50000 |
| +0 accept(3, ..., ...) = 4 |
| |
| // Kernel doubles our value -> sk->sk_sndbuf is set to 42000 |
| +0 setsockopt(4, SOL_SOCKET, SO_SNDBUF, [21000], 4) = 0 |
| +0 getsockopt(4, SOL_SOCKET, SO_SNDBUF, [42000], [4]) = 0 |
| |
| // A write of 60000 does not block. |
| +0...0.300 write(4, ..., 61000) = 61000 // this write() blocks |
| |
| +.1 < . 1:1(0) ack 10001 win 50000 |
| |
| +.1 < . 1:1(0) ack 30001 win 50000 |
| |
| // This ACK should wakeup the write(). An ACK of 35001 does not. |
| +.1 < . 1:1(0) ack 36001 win 50000 |
| |
| // Reset to sysctls defaults. |
| `/tmp/sysctl_restore_${PPID}.sh` |
