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>
8 #define BITS_PER_LONG __WORDSIZE
9 #define BITS_PER_BYTE 8
10 #define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
11 #define BITS_TO_U64(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(u64))
12 #define BITS_TO_U32(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(u32))
14 #define for_each_set_bit(bit, addr, size) \
15 for ((bit) = find_first_bit((addr), (size)); \
17 (bit) = find_next_bit((addr), (size), (bit) + 1))
19 /* same as for_each_set_bit() but use bit as value to start with */
20 #define for_each_set_bit_from(bit, addr, size) \
21 for ((bit) = find_next_bit((addr), (size), (bit)); \
23 (bit) = find_next_bit((addr), (size), (bit) + 1))
25 static inline void set_bit(int nr, unsigned long *addr)
27 addr[nr / BITS_PER_LONG] |= 1UL << (nr % BITS_PER_LONG);
30 static inline void clear_bit(int nr, unsigned long *addr)
32 addr[nr / BITS_PER_LONG] &= ~(1UL << (nr % BITS_PER_LONG));
35 static __always_inline int test_bit(unsigned int nr, const unsigned long *addr)
37 return ((1UL << (nr % BITS_PER_LONG)) &
38 (((unsigned long *)addr)[nr / BITS_PER_LONG])) != 0;
41 static inline unsigned long hweight_long(unsigned long w)
43 return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
46 #define BITOP_WORD(nr) ((nr) / BITS_PER_LONG)
49 * __ffs - find first bit in word.
50 * @word: The word to search
52 * Undefined if no bit exists, so code should check against 0 first.
54 static __always_inline unsigned long __ffs(unsigned long word)
58 #if BITS_PER_LONG == 64
59 if ((word & 0xffffffff) == 0) {
64 if ((word & 0xffff) == 0) {
68 if ((word & 0xff) == 0) {
72 if ((word & 0xf) == 0) {
76 if ((word & 0x3) == 0) {
80 if ((word & 0x1) == 0)
86 * Find the first set bit in a memory region.
88 static inline unsigned long
89 find_first_bit(const unsigned long *addr, unsigned long size)
91 const unsigned long *p = addr;
92 unsigned long result = 0;
95 while (size & ~(BITS_PER_LONG-1)) {
98 result += BITS_PER_LONG;
99 size -= BITS_PER_LONG;
104 tmp = (*p) & (~0UL >> (BITS_PER_LONG - size));
105 if (tmp == 0UL) /* Are any bits set? */
106 return result + size; /* Nope. */
108 return result + __ffs(tmp);
112 * Find the next set bit in a memory region.
114 static inline unsigned long
115 find_next_bit(const unsigned long *addr, unsigned long size, unsigned long offset)
117 const unsigned long *p = addr + BITOP_WORD(offset);
118 unsigned long result = offset & ~(BITS_PER_LONG-1);
124 offset %= BITS_PER_LONG;
127 tmp &= (~0UL << offset);
128 if (size < BITS_PER_LONG)
132 size -= BITS_PER_LONG;
133 result += BITS_PER_LONG;
135 while (size & ~(BITS_PER_LONG-1)) {
138 result += BITS_PER_LONG;
139 size -= BITS_PER_LONG;
146 tmp &= (~0UL >> (BITS_PER_LONG - size));
147 if (tmp == 0UL) /* Are any bits set? */
148 return result + size; /* Nope. */
150 return result + __ffs(tmp);