xref: /kvm-unit-tests/lib/cpumask.h (revision 27e44c5d3f4faeebb3b68937629808c7ab28e56f)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Simple cpumask implementation
4  *
5  * Copyright (C) 2015, Red Hat Inc, Andrew Jones <drjones@redhat.com>
6  */
7 #ifndef _CPUMASK_H_
8 #define _CPUMASK_H_
9 #include <bitops.h>
10 #include <limits.h>
11 #include <asm/setup.h>
12 
13 #define CPUMASK_NR_LONGS ((NR_CPUS + BITS_PER_LONG - 1) / BITS_PER_LONG)
14 
15 typedef struct cpumask {
16 	unsigned long bits[CPUMASK_NR_LONGS];
17 } cpumask_t;
18 
19 #define cpumask_bits(maskp) ((maskp)->bits)
20 
21 static inline void cpumask_set_cpu(int cpu, cpumask_t *mask)
22 {
23 	assert(cpu >= 0 && cpu < nr_cpus);
24 	set_bit(cpu, cpumask_bits(mask));
25 }
26 
27 static inline void cpumask_clear_cpu(int cpu, cpumask_t *mask)
28 {
29 	assert(cpu >= 0 && cpu < nr_cpus);
30 	clear_bit(cpu, cpumask_bits(mask));
31 }
32 
33 static inline int cpumask_test_cpu(int cpu, const cpumask_t *mask)
34 {
35 	assert(cpu >= 0 && cpu < nr_cpus);
36 	return test_bit(cpu, cpumask_bits(mask));
37 }
38 
39 static inline int cpumask_test_and_set_cpu(int cpu, cpumask_t *mask)
40 {
41 	assert(cpu >= 0 && cpu < nr_cpus);
42 	return test_and_set_bit(cpu, cpumask_bits(mask));
43 }
44 
45 static inline int cpumask_test_and_clear_cpu(int cpu, cpumask_t *mask)
46 {
47 	assert(cpu >= 0 && cpu < nr_cpus);
48 	return test_and_clear_bit(cpu, cpumask_bits(mask));
49 }
50 
51 static inline void cpumask_setall(cpumask_t *mask)
52 {
53 	memset(mask, 0xff, sizeof(*mask));
54 }
55 
56 static inline void cpumask_clear(cpumask_t *mask)
57 {
58 	memset(mask, 0, sizeof(*mask));
59 }
60 
61 /* true if src1 is a subset of src2 */
62 static inline bool cpumask_subset(const struct cpumask *src1, const struct cpumask *src2)
63 {
64 	unsigned long lastmask = BIT_MASK(nr_cpus) - 1;
65 	int i;
66 
67 	for (i = 0; i < BIT_WORD(nr_cpus); ++i) {
68 		if (cpumask_bits(src1)[i] & ~cpumask_bits(src2)[i])
69 			return false;
70 	}
71 
72 	return !lastmask || !((cpumask_bits(src1)[i] & ~cpumask_bits(src2)[i]) & lastmask);
73 }
74 
75 static inline bool cpumask_empty(const cpumask_t *mask)
76 {
77 	unsigned long lastmask = BIT_MASK(nr_cpus) - 1;
78 
79 	for (int i = 0; i < BIT_WORD(nr_cpus); ++i)
80 		if (cpumask_bits(mask)[i])
81 			return false;
82 
83 	return !lastmask || !(cpumask_bits(mask)[BIT_WORD(nr_cpus)] & lastmask);
84 }
85 
86 static inline bool cpumask_full(const cpumask_t *mask)
87 {
88 	unsigned long lastmask = BIT_MASK(nr_cpus) - 1;
89 
90 	for (int i = 0; i < BIT_WORD(nr_cpus); ++i)
91 		if (cpumask_bits(mask)[i] != ULONG_MAX)
92 			return false;
93 
94 	return !lastmask || (cpumask_bits(mask)[BIT_WORD(nr_cpus)] & lastmask) == lastmask;
95 }
96 
97 static inline int cpumask_weight(const cpumask_t *mask)
98 {
99 	int w = 0, i;
100 
101 	for (i = 0; i < nr_cpus; ++i)
102 		if (cpumask_test_cpu(i, mask))
103 			++w;
104 	return w;
105 }
106 
107 static inline void cpumask_copy(cpumask_t *dst, const cpumask_t *src)
108 {
109 	memcpy(cpumask_bits(dst), cpumask_bits(src),
110 			CPUMASK_NR_LONGS * sizeof(long));
111 }
112 
113 static inline int cpumask_next(int cpu, const cpumask_t *mask)
114 {
115 	while (++cpu < nr_cpus && !cpumask_test_cpu(cpu, mask))
116 		;
117 	return cpu;
118 }
119 
120 #define for_each_cpu(cpu, mask)					\
121 	for ((cpu) = cpumask_next(-1, mask);			\
122 			(cpu) < nr_cpus; 			\
123 			(cpu) = cpumask_next(cpu, mask))
124 
125 extern cpumask_t cpu_present_mask;
126 extern cpumask_t cpu_online_mask;
127 extern cpumask_t cpu_idle_mask;
128 #define cpu_present(cpu)		cpumask_test_cpu(cpu, &cpu_present_mask)
129 #define cpu_online(cpu)			cpumask_test_cpu(cpu, &cpu_online_mask)
130 #define cpu_idle(cpu)			cpumask_test_cpu(cpu, &cpu_idle_mask)
131 #define for_each_present_cpu(cpu)	for_each_cpu(cpu, &cpu_present_mask)
132 #define for_each_online_cpu(cpu)	for_each_cpu(cpu, &cpu_online_mask)
133 
134 static inline void set_cpu_present(int cpu, bool present)
135 {
136 	if (present)
137 		cpumask_set_cpu(cpu, &cpu_present_mask);
138 	else
139 		cpumask_clear_cpu(cpu, &cpu_present_mask);
140 }
141 
142 static inline void set_cpu_online(int cpu, bool online)
143 {
144 	if (online)
145 		cpumask_set_cpu(cpu, &cpu_online_mask);
146 	else
147 		cpumask_clear_cpu(cpu, &cpu_online_mask);
148 }
149 
150 static inline void set_cpu_idle(int cpu, bool idle)
151 {
152 	if (idle)
153 		cpumask_set_cpu(cpu, &cpu_idle_mask);
154 	else
155 		cpumask_clear_cpu(cpu, &cpu_idle_mask);
156 }
157 
158 #endif /* _CPUMASK_H_ */
159