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1// SPDX-License-Identifier: GPL-2.02#include <stdio.h>3#include <unistd.h>4#include <string.h>5#include <assert.h>6#include <bpf/libbpf.h>7#include <bpf/bpf.h>8#include "trace_helpers.h"9 10int main(int ac, char **argv)11{12 struct bpf_object *obj = NULL;13 struct bpf_link *links[20];14 long key, next_key, value;15 struct bpf_program *prog;16 int map_fd, i, j = 0;17 char filename[256];18 struct ksym *sym;19 20 if (load_kallsyms()) {21 printf("failed to process /proc/kallsyms\n");22 return 2;23 }24 25 snprintf(filename, sizeof(filename), "%s.bpf.o", argv[0]);26 obj = bpf_object__open_file(filename, NULL);27 if (libbpf_get_error(obj)) {28 fprintf(stderr, "ERROR: opening BPF object file failed\n");29 obj = NULL;30 goto cleanup;31 }32 33 /* load BPF program */34 if (bpf_object__load(obj)) {35 fprintf(stderr, "ERROR: loading BPF object file failed\n");36 goto cleanup;37 }38 39 map_fd = bpf_object__find_map_fd_by_name(obj, "my_map");40 if (map_fd < 0) {41 fprintf(stderr, "ERROR: finding a map in obj file failed\n");42 goto cleanup;43 }44 45 bpf_object__for_each_program(prog, obj) {46 links[j] = bpf_program__attach(prog);47 if (libbpf_get_error(links[j])) {48 fprintf(stderr, "bpf_program__attach failed\n");49 links[j] = NULL;50 goto cleanup;51 }52 j++;53 }54 55 for (i = 0; i < 5; i++) {56 key = 0;57 printf("kprobing funcs:");58 while (bpf_map_get_next_key(map_fd, &key, &next_key) == 0) {59 bpf_map_lookup_elem(map_fd, &next_key, &value);60 assert(next_key == value);61 sym = ksym_search(value);62 key = next_key;63 if (!sym) {64 printf("ksym not found. Is kallsyms loaded?\n");65 continue;66 }67 68 printf(" %s", sym->name);69 }70 if (key)71 printf("\n");72 key = 0;73 while (bpf_map_get_next_key(map_fd, &key, &next_key) == 0)74 bpf_map_delete_elem(map_fd, &next_key);75 sleep(1);76 }77 78cleanup:79 for (j--; j >= 0; j--)80 bpf_link__destroy(links[j]);81 82 bpf_object__close(obj);83 return 0;84}85