xref: /linux/tools/testing/selftests/bpf/progs/cpumask_common.h (revision 71e0ad345163c150ea15434b37036b0678d5f6f4)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */
3 
4 #ifndef _CPUMASK_COMMON_H
5 #define _CPUMASK_COMMON_H
6 
7 #include "errno.h"
8 #include <stdbool.h>
9 
10 /* Should use BTF_FIELDS_MAX, but it is not always available in vmlinux.h,
11  * so use the hard-coded number as a workaround.
12  */
13 #define CPUMASK_KPTR_FIELDS_MAX 11
14 
15 int err;
16 
17 #define private(name) SEC(".bss." #name) __attribute__((aligned(8)))
18 private(MASK) static struct bpf_cpumask __kptr * global_mask;
19 
20 struct __cpumask_map_value {
21 	struct bpf_cpumask __kptr * cpumask;
22 };
23 
24 struct array_map {
25 	__uint(type, BPF_MAP_TYPE_ARRAY);
26 	__type(key, int);
27 	__type(value, struct __cpumask_map_value);
28 	__uint(max_entries, 1);
29 } __cpumask_map SEC(".maps");
30 
31 struct bpf_cpumask *bpf_cpumask_create(void) __ksym __weak;
32 void bpf_cpumask_release(struct bpf_cpumask *cpumask) __ksym __weak;
33 struct bpf_cpumask *bpf_cpumask_acquire(struct bpf_cpumask *cpumask) __ksym __weak;
34 u32 bpf_cpumask_first(const struct cpumask *cpumask) __ksym __weak;
35 u32 bpf_cpumask_first_zero(const struct cpumask *cpumask) __ksym __weak;
36 u32 bpf_cpumask_first_and(const struct cpumask *src1,
37 			  const struct cpumask *src2) __ksym __weak;
38 void bpf_cpumask_set_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym __weak;
39 void bpf_cpumask_clear_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym __weak;
40 bool bpf_cpumask_test_cpu(u32 cpu, const struct cpumask *cpumask) __ksym __weak;
41 bool bpf_cpumask_test_and_set_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym __weak;
42 bool bpf_cpumask_test_and_clear_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym __weak;
43 void bpf_cpumask_setall(struct bpf_cpumask *cpumask) __ksym __weak;
44 void bpf_cpumask_clear(struct bpf_cpumask *cpumask) __ksym __weak;
45 bool bpf_cpumask_and(struct bpf_cpumask *cpumask,
46 		     const struct cpumask *src1,
47 		     const struct cpumask *src2) __ksym __weak;
48 void bpf_cpumask_or(struct bpf_cpumask *cpumask,
49 		    const struct cpumask *src1,
50 		    const struct cpumask *src2) __ksym __weak;
51 void bpf_cpumask_xor(struct bpf_cpumask *cpumask,
52 		     const struct cpumask *src1,
53 		     const struct cpumask *src2) __ksym __weak;
54 bool bpf_cpumask_equal(const struct cpumask *src1, const struct cpumask *src2) __ksym __weak;
55 bool bpf_cpumask_intersects(const struct cpumask *src1, const struct cpumask *src2) __ksym __weak;
56 bool bpf_cpumask_subset(const struct cpumask *src1, const struct cpumask *src2) __ksym __weak;
57 bool bpf_cpumask_empty(const struct cpumask *cpumask) __ksym __weak;
58 bool bpf_cpumask_full(const struct cpumask *cpumask) __ksym __weak;
59 void bpf_cpumask_copy(struct bpf_cpumask *dst, const struct cpumask *src) __ksym __weak;
60 u32 bpf_cpumask_any_distribute(const struct cpumask *src) __ksym __weak;
61 u32 bpf_cpumask_any_and_distribute(const struct cpumask *src1,
62 				   const struct cpumask *src2) __ksym __weak;
63 u32 bpf_cpumask_weight(const struct cpumask *cpumask) __ksym __weak;
64 
65 void bpf_rcu_read_lock(void) __ksym __weak;
66 void bpf_rcu_read_unlock(void) __ksym __weak;
67 
68 static inline const struct cpumask *cast(struct bpf_cpumask *cpumask)
69 {
70 	return (const struct cpumask *)cpumask;
71 }
72 
73 static inline struct bpf_cpumask *create_cpumask(void)
74 {
75 	struct bpf_cpumask *cpumask;
76 
77 	cpumask = bpf_cpumask_create();
78 	if (!cpumask) {
79 		err = 1;
80 		return NULL;
81 	}
82 
83 	if (!bpf_cpumask_empty(cast(cpumask))) {
84 		err = 2;
85 		bpf_cpumask_release(cpumask);
86 		return NULL;
87 	}
88 
89 	return cpumask;
90 }
91 
92 static inline struct __cpumask_map_value *cpumask_map_value_lookup(void)
93 {
94 	u32 key = 0;
95 
96 	return bpf_map_lookup_elem(&__cpumask_map, &key);
97 }
98 
99 static inline int cpumask_map_insert(struct bpf_cpumask *mask)
100 {
101 	struct __cpumask_map_value local, *v;
102 	long status;
103 	struct bpf_cpumask *old;
104 	u32 key = 0;
105 
106 	local.cpumask = NULL;
107 	status = bpf_map_update_elem(&__cpumask_map, &key, &local, 0);
108 	if (status) {
109 		bpf_cpumask_release(mask);
110 		return status;
111 	}
112 
113 	v = bpf_map_lookup_elem(&__cpumask_map, &key);
114 	if (!v) {
115 		bpf_cpumask_release(mask);
116 		return -ENOENT;
117 	}
118 
119 	old = bpf_kptr_xchg(&v->cpumask, mask);
120 	if (old) {
121 		bpf_cpumask_release(old);
122 		return -EEXIST;
123 	}
124 
125 	return 0;
126 }
127 
128 #endif /* _CPUMASK_COMMON_H */
129