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#ifndef _ASM_GENERIC_BITOPS_SCHED_H_
#define _ASM_GENERIC_BITOPS_SCHED_H_
#include <linux/compiler.h> /* unlikely() */
#include <asm/types.h>
/*
* Every architecture must define this function. It's the fastest
* way of searching a 140-bit bitmap where the first 100 bits are
* unlikely to be set. It's guaranteed that at least one of the 140
* bits is cleared.
*/
static inline int sched_find_first_bit(const unsigned long *b)
{
#if BITS_PER_LONG == 64
if (unlikely(b[0]))
return __ffs(b[0]);
if (likely(b[1]))
return __ffs(b[1]) + 64;
return __ffs(b[2]) + 128;
#elif BITS_PER_LONG == 32
if (unlikely(b[0]))
return __ffs(b[0]);
if (unlikely(b[1]))
return __ffs(b[1]) + 32;
if (unlikely(b[2]))
return __ffs(b[2]) + 64;
if (b[3])
return __ffs(b[3]) + 96;
return __ffs(b[4]) + 128;
#else
#error BITS_PER_LONG not defined
#endif
}
#endif /* _ASM_GENERIC_BITOPS_SCHED_H_ */
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