tools/testing/selftests/net/fin_ack_lat.c

Source file repositories/reference/linux-study-clean/tools/testing/selftests/net/fin_ack_lat.c

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/net/fin_ack_lat.c
Extension
.c
Size
3397 bytes
Lines
152
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0

#include <arpa/inet.h>
#include <errno.h>
#include <error.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <unistd.h>

static int child_pid;

static unsigned long timediff(struct timeval s, struct timeval e)
{
	unsigned long s_us, e_us;

	s_us = s.tv_sec * 1000000 + s.tv_usec;
	e_us = e.tv_sec * 1000000 + e.tv_usec;
	if (s_us > e_us)
		return 0;
	return e_us - s_us;
}

static void client(int port)
{
	int sock = 0;
	struct sockaddr_in addr, laddr;
	socklen_t len = sizeof(laddr);
	struct linger sl;
	int flag = 1;
	int buffer;
	struct timeval start, end;
	unsigned long lat, sum_lat = 0, nr_lat = 0;

	while (1) {
		gettimeofday(&start, NULL);

		sock = socket(AF_INET, SOCK_STREAM, 0);
		if (sock < 0)
			error(-1, errno, "socket creation");

		sl.l_onoff = 1;
		sl.l_linger = 0;
		if (setsockopt(sock, SOL_SOCKET, SO_LINGER, &sl, sizeof(sl)))
			error(-1, errno, "setsockopt(linger)");

		if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY,
					&flag, sizeof(flag)))
			error(-1, errno, "setsockopt(nodelay)");

		addr.sin_family = AF_INET;
		addr.sin_port = htons(port);

		if (inet_pton(AF_INET, "127.0.0.1", &addr.sin_addr) <= 0)
			error(-1, errno, "inet_pton");

		if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) < 0)
			error(-1, errno, "connect");

		send(sock, &buffer, sizeof(buffer), 0);
		if (read(sock, &buffer, sizeof(buffer)) == -1)
			error(-1, errno, "waiting read");

		gettimeofday(&end, NULL);
		lat = timediff(start, end);
		sum_lat += lat;
		nr_lat++;
		if (lat < 100000)
			goto close;

		if (getsockname(sock, (struct sockaddr *)&laddr, &len) == -1)
			error(-1, errno, "getsockname");
		printf("port: %d, lat: %lu, avg: %lu, nr: %lu\n",
				ntohs(laddr.sin_port), lat,
				sum_lat / nr_lat, nr_lat);
close:
		fflush(stdout);
		close(sock);
	}
}

static void server(int sock, struct sockaddr_in address)
{
	int accepted;
	int addrlen = sizeof(address);
	int buffer;

Annotation

Implementation Notes