stacktrace_ips.c

 1// SPDX-License-Identifier: GPL-2.0
 2// Copyright (c) 2018 Facebook
 3
 4#include <vmlinux.h>
 5#include <bpf/bpf_helpers.h>
 6#include <bpf/bpf_tracing.h>
 7
 8#ifndef PERF_MAX_STACK_DEPTH
 9#define PERF_MAX_STACK_DEPTH         127
10#endif
11
12typedef __u64 stack_trace_t[PERF_MAX_STACK_DEPTH];
13
14struct {
15	__uint(type, BPF_MAP_TYPE_STACK_TRACE);
16	__uint(max_entries, 16384);
17	__type(key, __u32);
18	__type(value, stack_trace_t);
19} stackmap SEC(".maps");
20
21extern bool CONFIG_UNWINDER_ORC __kconfig __weak;
22
23/*
24 * This function is here to have CONFIG_UNWINDER_ORC
25 * used and added to object BTF.
26 */
27int unused(void)
28{
29	return CONFIG_UNWINDER_ORC ? 0 : 1;
30}
31
32__u32 stack_key;
33
34SEC("kprobe.multi")
35int kprobe_multi_test(struct pt_regs *ctx)
36{
37	stack_key = bpf_get_stackid(ctx, &stackmap, 0);
38	return 0;
39}
40
41SEC("raw_tp/bpf_testmod_test_read")
42int rawtp_test(void *ctx)
43{
44	/* Skip ebpf program entry in the stack. */
45	stack_key = bpf_get_stackid(ctx, &stackmap, 0);
46	return 0;
47}
48
49char _license[] SEC("license") = "GPL";