106 lines · c
1// SPDX-License-Identifier: GPL-2.0-only2#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 100000ll21 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 bpf_link *link = NULL;47 struct bpf_program *prog;48 struct perf_buffer *pb;49 struct bpf_object *obj;50 int map_fd, ret = 0;51 char filename[256];52 FILE *f;53 54 snprintf(filename, sizeof(filename), "%s.bpf.o", argv[0]);55 obj = bpf_object__open_file(filename, NULL);56 if (libbpf_get_error(obj)) {57 fprintf(stderr, "ERROR: opening BPF object file failed\n");58 return 0;59 }60 61 /* load BPF program */62 if (bpf_object__load(obj)) {63 fprintf(stderr, "ERROR: loading BPF object file failed\n");64 goto cleanup;65 }66 67 map_fd = bpf_object__find_map_fd_by_name(obj, "my_map");68 if (map_fd < 0) {69 fprintf(stderr, "ERROR: finding a map in obj file failed\n");70 goto cleanup;71 }72 73 prog = bpf_object__find_program_by_name(obj, "bpf_prog1");74 if (libbpf_get_error(prog)) {75 fprintf(stderr, "ERROR: finding a prog in obj file failed\n");76 goto cleanup;77 }78 79 link = bpf_program__attach(prog);80 if (libbpf_get_error(link)) {81 fprintf(stderr, "ERROR: bpf_program__attach failed\n");82 link = NULL;83 goto cleanup;84 }85 86 pb = perf_buffer__new(map_fd, 8, print_bpf_output, NULL, NULL, NULL);87 ret = libbpf_get_error(pb);88 if (ret) {89 printf("failed to setup perf_buffer: %d\n", ret);90 return 1;91 }92 93 f = popen("taskset 1 dd if=/dev/zero of=/dev/null", "r");94 (void) f;95 96 start_time = time_get_ns();97 while ((ret = perf_buffer__poll(pb, 1000)) >= 0 && cnt < MAX_CNT) {98 }99 kill(0, SIGINT);100 101cleanup:102 bpf_link__destroy(link);103 bpf_object__close(obj);104 return ret;105}106