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