LXR linux/include/asm-generic/bitops/sched.h

   1#ifndef _ASM_GENERIC_BITOPS_SCHED_H_
   2#define _ASM_GENERIC_BITOPS_SCHED_H_
   3
   4#include <linux/compiler.h>     /* unlikely() */
   5#include <asm/types.h>
   6
   7/*
   8 * Every architecture must define this function. It's the fastest
   9 * way of searching a 100-bit bitmap.  It's guaranteed that at least
  10 * one of the 100 bits is cleared.
  11 */
  12static inline int sched_find_first_bit(const unsigned long *b)
  13{
  14#if BITS_PER_LONG == 64
  15        if (b[0])
  16                return __ffs(b[0]);
  17        return __ffs(b[1]) + 64;
  18#elif BITS_PER_LONG == 32
  19        if (b[0])
  20                return __ffs(b[0]);
  21        if (b[1])
  22                return __ffs(b[1]) + 32;
  23        if (b[2])
  24                return __ffs(b[2]) + 64;
  25        return __ffs(b[3]) + 96;
  26#else
  27#error BITS_PER_LONG not defined
  28#endif
  29}
  30
  31#endif /* _ASM_GENERIC_BITOPS_SCHED_H_ */
  32