summaryrefslogtreecommitdiff
path: root/samples/bpf/syscall_tp_kern.c
blob: 1d78819ffef19075bfc29adfa903c16b6d05e55e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2017 Facebook
 */
#include <uapi/linux/bpf.h>
#include "bpf_helpers.h"

struct syscalls_enter_open_args {
	unsigned long long unused;
	long syscall_nr;
	long filename_ptr;
	long flags;
	long mode;
};

struct syscalls_exit_open_args {
	unsigned long long unused;
	long syscall_nr;
	long ret;
};

struct bpf_map_def SEC("maps") enter_open_map = {
	.type = BPF_MAP_TYPE_ARRAY,
	.key_size = sizeof(u32),
	.value_size = sizeof(u32),
	.max_entries = 1,
};

struct bpf_map_def SEC("maps") exit_open_map = {
	.type = BPF_MAP_TYPE_ARRAY,
	.key_size = sizeof(u32),
	.value_size = sizeof(u32),
	.max_entries = 1,
};

static __always_inline void count(void *map)
{
	u32 key = 0;
	u32 *value, init_val = 1;

	value = bpf_map_lookup_elem(map, &key);
	if (value)
		*value += 1;
	else
		bpf_map_update_elem(map, &key, &init_val, BPF_NOEXIST);
}

SEC("tracepoint/syscalls/sys_enter_open")
int trace_enter_open(struct syscalls_enter_open_args *ctx)
{
	count((void *)&enter_open_map);
	return 0;
}

SEC("tracepoint/syscalls/sys_exit_open")
int trace_enter_exit(struct syscalls_exit_open_args *ctx)
{
	count((void *)&exit_open_map);
	return 0;
}