1 #ifndef _PERF_LINUX_BITOPS_H_
2 #define _PERF_LINUX_BITOPS_H_
3
4 #include <linux/kernel.h>
5 #include <linux/compiler.h>
6 #include <asm/hweight.h>
7
8 #ifdef __APPLE__
9 #define __SIZEOF_LONG__ 4
10 #endif
11
12 #ifndef __WORDSIZE
13 #define __WORDSIZE (__SIZEOF_LONG__ * 8)
14 #endif
15
16 #define BITS_PER_LONG __WORDSIZE
17 #define BITS_PER_BYTE 8
18 #define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
19 #define BITS_TO_U64(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(u64))
20 #define BITS_TO_U32(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(u32))
21 #define BITS_TO_BYTES(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE)
22
23 #define for_each_set_bit(bit, addr, size) \
24 for ((bit) = find_first_bit((addr), (size)); \
25 (bit) < (size); \
26 (bit) = find_next_bit((addr), (size), (bit) + 1))
27
28 /* same as for_each_set_bit() but use bit as value to start with */
29 #define for_each_set_bit_from(bit, addr, size) \
30 for ((bit) = find_next_bit((addr), (size), (bit)); \
31 (bit) < (size); \
32 (bit) = find_next_bit((addr), (size), (bit) + 1))
33
set_bit(int nr,unsigned long * addr)34 static inline void set_bit(int nr, unsigned long *addr)
35 {
36 addr[nr / BITS_PER_LONG] |= 1UL << (nr % BITS_PER_LONG);
37 }
38
clear_bit(int nr,unsigned long * addr)39 static inline void clear_bit(int nr, unsigned long *addr)
40 {
41 addr[nr / BITS_PER_LONG] &= ~(1UL << (nr % BITS_PER_LONG));
42 }
43
test_bit(unsigned int nr,const unsigned long * addr)44 static __always_inline int test_bit(unsigned int nr, const unsigned long *addr)
45 {
46 return ((1UL << (nr % BITS_PER_LONG)) &
47 (((unsigned long *)addr)[nr / BITS_PER_LONG])) != 0;
48 }
49
hweight_long(unsigned long w)50 static inline unsigned long hweight_long(unsigned long w)
51 {
52 return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
53 }
54
55 #define BITOP_WORD(nr) ((nr) / BITS_PER_LONG)
56
57 /**
58 * __ffs - find first bit in word.
59 * @word: The word to search
60 *
61 * Undefined if no bit exists, so code should check against 0 first.
62 */
__ffs(unsigned long word)63 static __always_inline unsigned long __ffs(unsigned long word)
64 {
65 int num = 0;
66
67 #if BITS_PER_LONG == 64
68 if ((word & 0xffffffff) == 0) {
69 num += 32;
70 word >>= 32;
71 }
72 #endif
73 if ((word & 0xffff) == 0) {
74 num += 16;
75 word >>= 16;
76 }
77 if ((word & 0xff) == 0) {
78 num += 8;
79 word >>= 8;
80 }
81 if ((word & 0xf) == 0) {
82 num += 4;
83 word >>= 4;
84 }
85 if ((word & 0x3) == 0) {
86 num += 2;
87 word >>= 2;
88 }
89 if ((word & 0x1) == 0)
90 num += 1;
91 return num;
92 }
93
94 /*
95 * Find the first set bit in a memory region.
96 */
97 static inline unsigned long
find_first_bit(const unsigned long * addr,unsigned long size)98 find_first_bit(const unsigned long *addr, unsigned long size)
99 {
100 const unsigned long *p = addr;
101 unsigned long result = 0;
102 unsigned long tmp;
103
104 while (size & ~(BITS_PER_LONG-1)) {
105 if ((tmp = *(p++)))
106 goto found;
107 result += BITS_PER_LONG;
108 size -= BITS_PER_LONG;
109 }
110 if (!size)
111 return result;
112
113 tmp = (*p) & (~0UL >> (BITS_PER_LONG - size));
114 if (tmp == 0UL) /* Are any bits set? */
115 return result + size; /* Nope. */
116 found:
117 return result + __ffs(tmp);
118 }
119
120 /*
121 * Find the next set bit in a memory region.
122 */
123 static inline unsigned long
find_next_bit(const unsigned long * addr,unsigned long size,unsigned long offset)124 find_next_bit(const unsigned long *addr, unsigned long size, unsigned long offset)
125 {
126 const unsigned long *p = addr + BITOP_WORD(offset);
127 unsigned long result = offset & ~(BITS_PER_LONG-1);
128 unsigned long tmp;
129
130 if (offset >= size)
131 return size;
132 size -= result;
133 offset %= BITS_PER_LONG;
134 if (offset) {
135 tmp = *(p++);
136 tmp &= (~0UL << offset);
137 if (size < BITS_PER_LONG)
138 goto found_first;
139 if (tmp)
140 goto found_middle;
141 size -= BITS_PER_LONG;
142 result += BITS_PER_LONG;
143 }
144 while (size & ~(BITS_PER_LONG-1)) {
145 if ((tmp = *(p++)))
146 goto found_middle;
147 result += BITS_PER_LONG;
148 size -= BITS_PER_LONG;
149 }
150 if (!size)
151 return result;
152 tmp = *p;
153
154 found_first:
155 tmp &= (~0UL >> (BITS_PER_LONG - size));
156 if (tmp == 0UL) /* Are any bits set? */
157 return result + size; /* Nope. */
158 found_middle:
159 return result + __ffs(tmp);
160 }
161
162 #endif
163