xref: /linux/tools/testing/selftests/bpf/progs/wq.c (revision a1ff5a7d78a036d6c2178ee5acd6ba4946243800)
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 	int ok_offset;
36 	struct bpf_wq w;
37 };
38 
39 struct {
40 	__uint(type, BPF_MAP_TYPE_ARRAY);
41 	__uint(max_entries, 2);
42 	__type(key, int);
43 	__type(value, struct elem);
44 } array SEC(".maps");
45 
46 struct {
47 	__uint(type, BPF_MAP_TYPE_LRU_HASH);
48 	__uint(max_entries, 4);
49 	__type(key, int);
50 	__type(value, struct elem);
51 } lru SEC(".maps");
52 
53 __u32 ok;
54 __u32 ok_sleepable;
55 
test_elem_callback(void * map,int * key,int (callback_fn)(void * map,int * key,void * value))56 static int test_elem_callback(void *map, int *key,
57 		int (callback_fn)(void *map, int *key, void *value))
58 {
59 	struct elem init = {}, *val;
60 	struct bpf_wq *wq;
61 
62 	if ((ok & (1 << *key) ||
63 	    (ok_sleepable & (1 << *key))))
64 		return -22;
65 
66 	if (map == &lru &&
67 	    bpf_map_update_elem(map, key, &init, 0))
68 		return -1;
69 
70 	val = bpf_map_lookup_elem(map, key);
71 	if (!val)
72 		return -2;
73 
74 	val->ok_offset = *key;
75 
76 	wq = &val->w;
77 	if (bpf_wq_init(wq, map, 0) != 0)
78 		return -3;
79 
80 	if (bpf_wq_set_callback(wq, callback_fn, 0))
81 		return -4;
82 
83 	if (bpf_wq_start(wq, 0))
84 		return -5;
85 
86 	return 0;
87 }
88 
test_hmap_elem_callback(void * map,int * key,int (callback_fn)(void * map,int * key,void * value))89 static int test_hmap_elem_callback(void *map, int *key,
90 		int (callback_fn)(void *map, int *key, void *value))
91 {
92 	struct hmap_elem init = {}, *val;
93 	struct bpf_wq *wq;
94 
95 	if ((ok & (1 << *key) ||
96 	    (ok_sleepable & (1 << *key))))
97 		return -22;
98 
99 	if (bpf_map_update_elem(map, key, &init, 0))
100 		return -1;
101 
102 	val = bpf_map_lookup_elem(map, key);
103 	if (!val)
104 		return -2;
105 
106 	wq = &val->work;
107 	if (bpf_wq_init(wq, map, 0) != 0)
108 		return -3;
109 
110 	if (bpf_wq_set_callback(wq, callback_fn, 0))
111 		return -4;
112 
113 	if (bpf_wq_start(wq, 0))
114 		return -5;
115 
116 	return 0;
117 }
118 
119 /* callback for non sleepable workqueue */
wq_callback(void * map,int * key,void * value)120 static int wq_callback(void *map, int *key, void *value)
121 {
122 	bpf_kfunc_common_test();
123 	ok |= (1 << *key);
124 	return 0;
125 }
126 
127 /* callback for sleepable workqueue */
wq_cb_sleepable(void * map,int * key,void * value)128 static int wq_cb_sleepable(void *map, int *key, void *value)
129 {
130 	struct elem *data = (struct elem *)value;
131 	int offset = data->ok_offset;
132 
133 	if (*key != offset)
134 		return 0;
135 
136 	bpf_kfunc_call_test_sleepable();
137 	ok_sleepable |= (1 << offset);
138 	return 0;
139 }
140 
141 SEC("tc")
142 /* test that workqueues can be used from an array */
143 __retval(0)
test_call_array_sleepable(void * ctx)144 long test_call_array_sleepable(void *ctx)
145 {
146 	int key = 0;
147 
148 	return test_elem_callback(&array, &key, wq_cb_sleepable);
149 }
150 
151 SEC("syscall")
152 /* Same test than above but from a sleepable context. */
153 __retval(0)
test_syscall_array_sleepable(void * ctx)154 long test_syscall_array_sleepable(void *ctx)
155 {
156 	int key = 1;
157 
158 	return test_elem_callback(&array, &key, wq_cb_sleepable);
159 }
160 
161 SEC("tc")
162 /* test that workqueues can be used from a hashmap */
163 __retval(0)
test_call_hash_sleepable(void * ctx)164 long test_call_hash_sleepable(void *ctx)
165 {
166 	int key = 2;
167 
168 	return test_hmap_elem_callback(&hmap, &key, wq_callback);
169 }
170 
171 SEC("tc")
172 /* test that workqueues can be used from a hashmap with NO_PREALLOC. */
173 __retval(0)
test_call_hash_malloc_sleepable(void * ctx)174 long test_call_hash_malloc_sleepable(void *ctx)
175 {
176 	int key = 3;
177 
178 	return test_hmap_elem_callback(&hmap_malloc, &key, wq_callback);
179 }
180 
181 SEC("tc")
182 /* test that workqueues can be used from a LRU map */
183 __retval(0)
test_call_lru_sleepable(void * ctx)184 long test_call_lru_sleepable(void *ctx)
185 {
186 	int key = 4;
187 
188 	return test_elem_callback(&lru, &key, wq_callback);
189 }
190