LXR linux/tools/include/linux/bitmap.h

   1#ifndef _PERF_BITOPS_H
   2#define _PERF_BITOPS_H
   3
   4#include <string.h>
   5#include <linux/bitops.h>
   6
   7#define DECLARE_BITMAP(name,bits) \
   8        unsigned long name[BITS_TO_LONGS(bits)]
   9
  10int __bitmap_weight(const unsigned long *bitmap, int bits);
  11void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
  12                 const unsigned long *bitmap2, int bits);
  13
  14#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1)))
  15
  16#define BITMAP_LAST_WORD_MASK(nbits)                                    \
  17(                                                                       \
  18        ((nbits) % BITS_PER_LONG) ?                                     \
  19                (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL               \
  20)
  21
  22#define small_const_nbits(nbits) \
  23        (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG)
  24
  25static inline void bitmap_zero(unsigned long *dst, int nbits)
  26{
  27        if (small_const_nbits(nbits))
  28                *dst = 0UL;
  29        else {
  30                int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
  31                memset(dst, 0, len);
  32        }
  33}
  34
  35static inline int bitmap_weight(const unsigned long *src, int nbits)
  36{
  37        if (small_const_nbits(nbits))
  38                return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
  39        return __bitmap_weight(src, nbits);
  40}
  41
  42static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
  43                             const unsigned long *src2, int nbits)
  44{
  45        if (small_const_nbits(nbits))
  46                *dst = *src1 | *src2;
  47        else
  48                __bitmap_or(dst, src1, src2, nbits);
  49}
  50
  51/**
  52 * test_and_set_bit - Set a bit and return its old value
  53 * @nr: Bit to set
  54 * @addr: Address to count from
  55 */
  56static inline int test_and_set_bit(int nr, unsigned long *addr)
  57{
  58        unsigned long mask = BIT_MASK(nr);
  59        unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
  60        unsigned long old;
  61
  62        old = *p;
  63        *p = old | mask;
  64
  65        return (old & mask) != 0;
  66}
  67
  68#endif /* _PERF_BITOPS_H */
  69