1 #ifndef _PERF_LINUX_BITOPS_H_
2 #define _PERF_LINUX_BITOPS_H_
4 #include <linux/kernel.h>
5 #include <linux/compiler.h>
6 #include <asm/hweight.h>
9 #define __WORDSIZE (__SIZEOF_LONG__ * 8)
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)
19 #define for_each_set_bit(bit, addr, size) \
20 for ((bit) = find_first_bit((addr), (size)); \
22 (bit) = find_next_bit((addr), (size), (bit) + 1))
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)); \
28 (bit) = find_next_bit((addr), (size), (bit) + 1))
30 static inline void set_bit(int nr, unsigned long *addr)
32 addr[nr / BITS_PER_LONG] |= 1UL << (nr % BITS_PER_LONG);
35 static inline void clear_bit(int nr, unsigned long *addr)
37 addr[nr / BITS_PER_LONG] &= ~(1UL << (nr % BITS_PER_LONG));
40 static __always_inline int test_bit(unsigned int nr, const unsigned long *addr)
42 return ((1UL << (nr % BITS_PER_LONG)) &
43 (((unsigned long *)addr)[nr / BITS_PER_LONG])) != 0;
46 static inline unsigned long hweight_long(unsigned long w)
48 return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
51 #define BITOP_WORD(nr) ((nr) / BITS_PER_LONG)
54 * __ffs - find first bit in word.
55 * @word: The word to search
57 * Undefined if no bit exists, so code should check against 0 first.
59 static __always_inline unsigned long __ffs(unsigned long word)
63 #if BITS_PER_LONG == 64
64 if ((word & 0xffffffff) == 0) {
69 if ((word & 0xffff) == 0) {
73 if ((word & 0xff) == 0) {
77 if ((word & 0xf) == 0) {
81 if ((word & 0x3) == 0) {
85 if ((word & 0x1) == 0)
91 * Find the first set bit in a memory region.
93 static inline unsigned long
94 find_first_bit(const unsigned long *addr, unsigned long size)
96 const unsigned long *p = addr;
97 unsigned long result = 0;
100 while (size & ~(BITS_PER_LONG-1)) {
103 result += BITS_PER_LONG;
104 size -= BITS_PER_LONG;
109 tmp = (*p) & (~0UL >> (BITS_PER_LONG - size));
110 if (tmp == 0UL) /* Are any bits set? */
111 return result + size; /* Nope. */
113 return result + __ffs(tmp);
117 * Find the next set bit in a memory region.
119 static inline unsigned long
120 find_next_bit(const unsigned long *addr, unsigned long size, unsigned long offset)
122 const unsigned long *p = addr + BITOP_WORD(offset);
123 unsigned long result = offset & ~(BITS_PER_LONG-1);
129 offset %= BITS_PER_LONG;
132 tmp &= (~0UL << offset);
133 if (size < BITS_PER_LONG)
137 size -= BITS_PER_LONG;
138 result += BITS_PER_LONG;
140 while (size & ~(BITS_PER_LONG-1)) {
143 result += BITS_PER_LONG;
144 size -= BITS_PER_LONG;
151 tmp &= (~0UL >> (BITS_PER_LONG - size));
152 if (tmp == 0UL) /* Are any bits set? */
153 return result + size; /* Nope. */
155 return result + __ffs(tmp);