1// SPDX-License-Identifier: GPL-2.0-only
  2#include <stdio.h>
  3#include <fcntl.h>
  4#include <poll.h>
  5#include <time.h>
  6#include <signal.h>
  7#include <bpf/libbpf.h>
  8
  9static __u64 time_get_ns(void)
 10{
 11	struct timespec ts;
 12
 13	clock_gettime(CLOCK_MONOTONIC, &ts);
 14	return ts.tv_sec * 1000000000ull + ts.tv_nsec;
 15}
 16
 17static __u64 start_time;
 18static __u64 cnt;
 19
 20#define MAX_CNT 100000ll
 21
 22static void print_bpf_output(void *ctx, int cpu, void *data, __u32 size)
 23{
 24	struct {
 25		__u64 pid;
 26		__u64 cookie;
 27	} *e = data;
 28
 29	if (e->cookie != 0x12345678) {
 30		printf("BUG pid %llx cookie %llx sized %d\n",
 31		       e->pid, e->cookie, size);
 32		return;
 33	}
 34
 35	cnt++;
 36
 37	if (cnt == MAX_CNT) {
 38		printf("recv %lld events per sec\n",
 39		       MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
 40		return;
 41	}
 42}
 43
 44int main(int argc, char **argv)
 45{
 46	struct perf_buffer_opts pb_opts = {};
 47	struct bpf_link *link = NULL;
 48	struct bpf_program *prog;
 49	struct perf_buffer *pb;
 50	struct bpf_object *obj;
 51	int map_fd, ret = 0;
 52	char filename[256];
 53	FILE *f;
 54
 55	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 56	obj = bpf_object__open_file(filename, NULL);
 57	if (libbpf_get_error(obj)) {
 58		fprintf(stderr, "ERROR: opening BPF object file failed\n");
 59		return 0;
 60	}
 61
 62	/* load BPF program */
 63	if (bpf_object__load(obj)) {
 64		fprintf(stderr, "ERROR: loading BPF object file failed\n");
 65		goto cleanup;
 66	}
 67
 68	map_fd = bpf_object__find_map_fd_by_name(obj, "my_map");
 69	if (map_fd < 0) {
 70		fprintf(stderr, "ERROR: finding a map in obj file failed\n");
 71		goto cleanup;
 72	}
 73
 74	prog = bpf_object__find_program_by_name(obj, "bpf_prog1");
 75	if (libbpf_get_error(prog)) {
 76		fprintf(stderr, "ERROR: finding a prog in obj file failed\n");
 77		goto cleanup;
 78	}
 79
 80	link = bpf_program__attach(prog);
 81	if (libbpf_get_error(link)) {
 82		fprintf(stderr, "ERROR: bpf_program__attach failed\n");
 83		link = NULL;
 84		goto cleanup;
 85	}
 86
 87	pb_opts.sample_cb = print_bpf_output;
 88	pb = perf_buffer__new(map_fd, 8, &pb_opts);
 89	ret = libbpf_get_error(pb);
 90	if (ret) {
 91		printf("failed to setup perf_buffer: %d\n", ret);
 92		return 1;
 93	}
 94
 95	f = popen("taskset 1 dd if=/dev/zero of=/dev/null", "r");
 96	(void) f;
 97
 98	start_time = time_get_ns();
 99	while ((ret = perf_buffer__poll(pb, 1000)) >= 0 && cnt < MAX_CNT) {
100	}
101	kill(0, SIGINT);
102
103cleanup:
104	bpf_link__destroy(link);
105	bpf_object__close(obj);
106	return ret;
107}