1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2016 Facebook
10 #include <linux/perf_event.h>
14 #include <sys/resource.h>
17 #include "trace_helpers.h"
19 #define PRINT_RAW_ADDR 0
21 static void print_ksym(__u64 addr)
27 sym = ksym_search(addr);
29 printf("ksym not found. Is kallsyms loaded?\n");
34 printf("%s/%llx;", sym->name, addr);
36 printf("%s;", sym->name);
39 #define TASK_COMM_LEN 16
42 char waker[TASK_COMM_LEN];
43 char target[TASK_COMM_LEN];
48 static void print_stack(struct key_t *key, __u64 count)
50 __u64 ip[PERF_MAX_STACK_DEPTH] = {};
54 printf("%s;", key->target);
55 if (bpf_map_lookup_elem(map_fd[3], &key->tret, ip) != 0) {
58 for (i = PERF_MAX_STACK_DEPTH - 1; i >= 0; i--)
62 if (bpf_map_lookup_elem(map_fd[3], &key->wret, ip) != 0) {
65 for (i = 0; i < PERF_MAX_STACK_DEPTH; i++)
68 printf(";%s %lld\n", key->waker, count);
70 if ((key->tret == -EEXIST || key->wret == -EEXIST) && !warned) {
71 printf("stackmap collisions seen. Consider increasing size\n");
73 } else if (((int)(key->tret) < 0 || (int)(key->wret) < 0)) {
74 printf("err stackid %d %d\n", key->tret, key->wret);
78 static void print_stacks(int fd)
80 struct key_t key = {}, next_key;
83 while (bpf_map_get_next_key(fd, &key, &next_key) == 0) {
84 bpf_map_lookup_elem(fd, &next_key, &value);
85 print_stack(&next_key, value);
90 static void int_exit(int sig)
92 print_stacks(map_fd[0]);
96 int main(int argc, char **argv)
98 struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
102 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
103 setrlimit(RLIMIT_MEMLOCK, &r);
105 signal(SIGINT, int_exit);
106 signal(SIGTERM, int_exit);
108 if (load_kallsyms()) {
109 printf("failed to process /proc/kallsyms\n");
113 if (load_bpf_file(filename)) {
114 printf("%s", bpf_log_buf);
119 delay = atoi(argv[1]);
121 print_stacks(map_fd[0]);