1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) 2023. Huawei Technologies Co., Ltd */
3 #include <vmlinux.h>
4 #include <bpf/bpf_tracing.h>
5 #include <bpf/bpf_helpers.h>
6
7 #include "bpf_experimental.h"
8
9 struct bin_data {
10 char data[256];
11 struct bpf_spin_lock lock;
12 };
13
14 struct map_value {
15 struct bin_data __kptr * data;
16 };
17
18 struct {
19 __uint(type, BPF_MAP_TYPE_ARRAY);
20 __type(key, int);
21 __type(value, struct map_value);
22 __uint(max_entries, 2048);
23 } array SEC(".maps");
24
25 char _license[] SEC("license") = "GPL";
26
27 bool nomem_err = false;
28
29 static int del_array(unsigned int i, int *from)
30 {
31 struct map_value *value;
32 struct bin_data *old;
33
34 value = bpf_map_lookup_elem(&array, from);
35 if (!value)
36 return 1;
37
38 old = bpf_kptr_xchg(&value->data, NULL);
39 if (old)
40 bpf_obj_drop(old);
41
42 (*from)++;
43 return 0;
44 }
45
46 static int add_array(unsigned int i, int *from)
47 {
48 struct bin_data *old, *new;
49 struct map_value *value;
50
51 value = bpf_map_lookup_elem(&array, from);
52 if (!value)
53 return 1;
54
55 new = bpf_obj_new(typeof(*new));
56 if (!new) {
57 nomem_err = true;
58 return 1;
59 }
60
61 old = bpf_kptr_xchg(&value->data, new);
62 if (old)
63 bpf_obj_drop(old);
64
65 (*from)++;
66 return 0;
67 }
68
69 static void del_then_add_array(int from)
70 {
71 int i;
72
73 i = from;
74 bpf_loop(512, del_array, &i, 0);
75
76 i = from;
77 bpf_loop(512, add_array, &i, 0);
78 }
79
80 SEC("fentry/bpf_fentry_test1")
81 int BPF_PROG2(test0, int, a)
82 {
83 del_then_add_array(0);
84 return 0;
85 }
86
87 SEC("fentry/bpf_fentry_test2")
88 int BPF_PROG2(test1, int, a, u64, b)
89 {
90 del_then_add_array(512);
91 return 0;
92 }
93
94 SEC("fentry/bpf_fentry_test3")
95 int BPF_PROG2(test2, char, a, int, b, u64, c)
96 {
97 del_then_add_array(1024);
98 return 0;
99 }
100
101 SEC("fentry/bpf_fentry_test4")
102 int BPF_PROG2(test3, void *, a, char, b, int, c, u64, d)
103 {
104 del_then_add_array(1536);
105 return 0;
106 }
107
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