xref: /linux/tools/testing/selftests/bpf/progs/wq.c (revision 001821b0e79716c4e17c71d8e053a23599a7a508)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2024 Benjamin Tissoires
3  */
4 
5 #include "bpf_experimental.h"
6 #include <bpf/bpf_helpers.h>
7 #include "bpf_misc.h"
8 #include "../bpf_testmod/bpf_testmod_kfunc.h"
9 
10 char _license[] SEC("license") = "GPL";
11 
12 struct hmap_elem {
13 	int counter;
14 	struct bpf_timer timer; /* unused */
15 	struct bpf_spin_lock lock; /* unused */
16 	struct bpf_wq work;
17 };
18 
19 struct {
20 	__uint(type, BPF_MAP_TYPE_HASH);
21 	__uint(max_entries, 1000);
22 	__type(key, int);
23 	__type(value, struct hmap_elem);
24 } hmap SEC(".maps");
25 
26 struct {
27 	__uint(type, BPF_MAP_TYPE_HASH);
28 	__uint(map_flags, BPF_F_NO_PREALLOC);
29 	__uint(max_entries, 1000);
30 	__type(key, int);
31 	__type(value, struct hmap_elem);
32 } hmap_malloc SEC(".maps");
33 
34 struct elem {
35 	struct bpf_wq w;
36 };
37 
38 struct {
39 	__uint(type, BPF_MAP_TYPE_ARRAY);
40 	__uint(max_entries, 2);
41 	__type(key, int);
42 	__type(value, struct elem);
43 } array SEC(".maps");
44 
45 struct {
46 	__uint(type, BPF_MAP_TYPE_LRU_HASH);
47 	__uint(max_entries, 4);
48 	__type(key, int);
49 	__type(value, struct elem);
50 } lru SEC(".maps");
51 
52 __u32 ok;
53 __u32 ok_sleepable;
54 
55 static int test_elem_callback(void *map, int *key,
56 		int (callback_fn)(void *map, int *key, struct bpf_wq *wq))
57 {
58 	struct elem init = {}, *val;
59 	struct bpf_wq *wq;
60 
61 	if ((ok & (1 << *key) ||
62 	    (ok_sleepable & (1 << *key))))
63 		return -22;
64 
65 	if (map == &lru &&
66 	    bpf_map_update_elem(map, key, &init, 0))
67 		return -1;
68 
69 	val = bpf_map_lookup_elem(map, key);
70 	if (!val)
71 		return -2;
72 
73 	wq = &val->w;
74 	if (bpf_wq_init(wq, map, 0) != 0)
75 		return -3;
76 
77 	if (bpf_wq_set_callback(wq, callback_fn, 0))
78 		return -4;
79 
80 	if (bpf_wq_start(wq, 0))
81 		return -5;
82 
83 	return 0;
84 }
85 
86 static int test_hmap_elem_callback(void *map, int *key,
87 		int (callback_fn)(void *map, int *key, struct bpf_wq *wq))
88 {
89 	struct hmap_elem init = {}, *val;
90 	struct bpf_wq *wq;
91 
92 	if ((ok & (1 << *key) ||
93 	    (ok_sleepable & (1 << *key))))
94 		return -22;
95 
96 	if (bpf_map_update_elem(map, key, &init, 0))
97 		return -1;
98 
99 	val = bpf_map_lookup_elem(map, key);
100 	if (!val)
101 		return -2;
102 
103 	wq = &val->work;
104 	if (bpf_wq_init(wq, map, 0) != 0)
105 		return -3;
106 
107 	if (bpf_wq_set_callback(wq, callback_fn, 0))
108 		return -4;
109 
110 	if (bpf_wq_start(wq, 0))
111 		return -5;
112 
113 	return 0;
114 }
115 
116 /* callback for non sleepable workqueue */
117 static int wq_callback(void *map, int *key, struct bpf_wq *work)
118 {
119 	bpf_kfunc_common_test();
120 	ok |= (1 << *key);
121 	return 0;
122 }
123 
124 /* callback for sleepable workqueue */
125 static int wq_cb_sleepable(void *map, int *key, struct bpf_wq *work)
126 {
127 	bpf_kfunc_call_test_sleepable();
128 	ok_sleepable |= (1 << *key);
129 	return 0;
130 }
131 
132 SEC("tc")
133 /* test that workqueues can be used from an array */
134 __retval(0)
135 long test_call_array_sleepable(void *ctx)
136 {
137 	int key = 0;
138 
139 	return test_elem_callback(&array, &key, wq_cb_sleepable);
140 }
141 
142 SEC("syscall")
143 /* Same test than above but from a sleepable context. */
144 __retval(0)
145 long test_syscall_array_sleepable(void *ctx)
146 {
147 	int key = 1;
148 
149 	return test_elem_callback(&array, &key, wq_cb_sleepable);
150 }
151 
152 SEC("tc")
153 /* test that workqueues can be used from a hashmap */
154 __retval(0)
155 long test_call_hash_sleepable(void *ctx)
156 {
157 	int key = 2;
158 
159 	return test_hmap_elem_callback(&hmap, &key, wq_callback);
160 }
161 
162 SEC("tc")
163 /* test that workqueues can be used from a hashmap with NO_PREALLOC. */
164 __retval(0)
165 long test_call_hash_malloc_sleepable(void *ctx)
166 {
167 	int key = 3;
168 
169 	return test_hmap_elem_callback(&hmap_malloc, &key, wq_callback);
170 }
171 
172 SEC("tc")
173 /* test that workqueues can be used from a LRU map */
174 __retval(0)
175 long test_call_lru_sleepable(void *ctx)
176 {
177 	int key = 4;
178 
179 	return test_elem_callback(&lru, &key, wq_callback);
180 }
181