samples/bpf/ibumad_user.c

Source file repositories/reference/linux-study-clean/samples/bpf/ibumad_user.c

File Facts

System
Linux kernel
Corpus path
samples/bpf/ibumad_user.c
Extension
.c
Size
3439 bytes
Lines
159
Domain
Support Tooling And Documentation
Bucket
samples
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

if (bpf_map_lookup_elem(fd, &key, &value)) {
			printf("failed to read key %u\n", key);
			continue;
		}
		if (value)
			printf("0x%02x : %llu\n", key, value);
	}
}

static void dump_all_counts(void)
{
	printf("Read 'Class : count'\n");
	dump_counts(map_fd[0]);
	printf("Write 'Class : count'\n");
	dump_counts(map_fd[1]);
}

static void dump_exit(int sig)
{
	dump_all_counts();
	/* Detach tracepoints */
	while (tp_cnt)
		bpf_link__destroy(tp_links[--tp_cnt]);

	bpf_object__close(obj);
	exit(0);
}

static const struct option long_options[] = {
	{"help",      no_argument,       NULL, 'h'},
	{"delay",     required_argument, NULL, 'd'},
};

static void usage(char *cmd)
{
	printf("eBPF test program to count packets from various IP addresses\n"
		"Usage: %s <options>\n"
		"       --help,   -h  this menu\n"
		"       --delay,  -d  <delay>  wait <delay> sec between prints [1 - 1000000]\n"
		, cmd
		);
}

int main(int argc, char **argv)
{
	struct bpf_program *prog;
	unsigned long delay = 5;
	char filename[256];
	int longindex = 0;
	int opt, err = -1;

	while ((opt = getopt_long(argc, argv, "hd:rSw",
				  long_options, &longindex)) != -1) {
		switch (opt) {
		case 'd':
			delay = strtoul(optarg, NULL, 0);
			if (delay == ULONG_MAX || delay < 0 ||
			    delay > 1000000) {
				fprintf(stderr, "ERROR: invalid delay : %s\n",
					optarg);
				usage(argv[0]);
				return 1;
			}
			break;
		default:
		case 'h':
			usage(argv[0]);
			return 1;
		}
	}

	/* Do one final dump when exiting */
	signal(SIGINT, dump_exit);
	signal(SIGTERM, dump_exit);

	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
	obj = bpf_object__open_file(filename, NULL);
	if (libbpf_get_error(obj)) {
		fprintf(stderr, "ERROR: opening BPF object file failed\n");
		return err;
	}

	/* load BPF program */
	if (bpf_object__load(obj)) {
		fprintf(stderr, "ERROR: loading BPF object file failed\n");
		goto cleanup;
	}

	map_fd[0] = bpf_object__find_map_fd_by_name(obj, "read_count");
	map_fd[1] = bpf_object__find_map_fd_by_name(obj, "write_count");

Annotation

Implementation Notes