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// SPDX-License-Identifier: GPL-2.0
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <assert.h>
#include <sys/resource.h>
#include <bpf/libbpf.h>
#include <bpf/bpf.h>
#include "trace_helpers.h"
int main(int ac, char **argv)
{
struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
char filename[256], symbol[256];
struct bpf_object *obj = NULL;
struct bpf_link *links[20];
long key, next_key, value;
struct bpf_program *prog;
int map_fd, i, j = 0;
const char *section;
struct ksym *sym;
if (setrlimit(RLIMIT_MEMLOCK, &r)) {
perror("setrlimit(RLIMIT_MEMLOCK)");
return 1;
}
if (load_kallsyms()) {
printf("failed to process /proc/kallsyms\n");
return 2;
}
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");
obj = NULL;
goto cleanup;
}
/* load BPF program */
if (bpf_object__load(obj)) {
fprintf(stderr, "ERROR: loading BPF object file failed\n");
goto cleanup;
}
map_fd = bpf_object__find_map_fd_by_name(obj, "my_map");
if (map_fd < 0) {
fprintf(stderr, "ERROR: finding a map in obj file failed\n");
goto cleanup;
}
bpf_object__for_each_program(prog, obj) {
section = bpf_program__section_name(prog);
if (sscanf(section, "kprobe/%s", symbol) != 1)
continue;
/* Attach prog only when symbol exists */
if (ksym_get_addr(symbol)) {
links[j] = bpf_program__attach(prog);
if (libbpf_get_error(links[j])) {
fprintf(stderr, "bpf_program__attach failed\n");
links[j] = NULL;
goto cleanup;
}
j++;
}
}
for (i = 0; i < 5; i++) {
key = 0;
printf("kprobing funcs:");
while (bpf_map_get_next_key(map_fd, &key, &next_key) == 0) {
bpf_map_lookup_elem(map_fd, &next_key, &value);
assert(next_key == value);
sym = ksym_search(value);
key = next_key;
if (!sym) {
printf("ksym not found. Is kallsyms loaded?\n");
continue;
}
printf(" %s", sym->name);
}
if (key)
printf("\n");
key = 0;
while (bpf_map_get_next_key(map_fd, &key, &next_key) == 0)
bpf_map_delete_elem(map_fd, &next_key);
sleep(1);
}
cleanup:
for (j--; j >= 0; j--)
bpf_link__destroy(links[j]);
bpf_object__close(obj);
return 0;
}
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