diff options
Diffstat (limited to 'tools/perf/util/include/linux/bitops.h')
| -rw-r--r-- | tools/perf/util/include/linux/bitops.h | 118 | 
1 files changed, 118 insertions, 0 deletions
diff --git a/tools/perf/util/include/linux/bitops.h b/tools/perf/util/include/linux/bitops.h index 305c8484f20..62cdee78db7 100644 --- a/tools/perf/util/include/linux/bitops.h +++ b/tools/perf/util/include/linux/bitops.h @@ -9,6 +9,17 @@  #define BITS_PER_BYTE           8  #define BITS_TO_LONGS(nr)       DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long)) +#define for_each_set_bit(bit, addr, size) \ +	for ((bit) = find_first_bit((addr), (size));		\ +	     (bit) < (size);					\ +	     (bit) = find_next_bit((addr), (size), (bit) + 1)) + +/* same as for_each_set_bit() but use bit as value to start with */ +#define for_each_set_bit_cont(bit, addr, size) \ +	for ((bit) = find_next_bit((addr), (size), (bit));	\ +	     (bit) < (size);					\ +	     (bit) = find_next_bit((addr), (size), (bit) + 1)) +  static inline void set_bit(int nr, unsigned long *addr)  {  	addr[nr / BITS_PER_LONG] |= 1UL << (nr % BITS_PER_LONG); @@ -30,4 +41,111 @@ static inline unsigned long hweight_long(unsigned long w)  	return sizeof(w) == 4 ? hweight32(w) : hweight64(w);  } +#define BITOP_WORD(nr)		((nr) / BITS_PER_LONG) + +/** + * __ffs - find first bit in word. + * @word: The word to search + * + * Undefined if no bit exists, so code should check against 0 first. + */ +static __always_inline unsigned long __ffs(unsigned long word) +{ +	int num = 0; + +#if BITS_PER_LONG == 64 +	if ((word & 0xffffffff) == 0) { +		num += 32; +		word >>= 32; +	} +#endif +	if ((word & 0xffff) == 0) { +		num += 16; +		word >>= 16; +	} +	if ((word & 0xff) == 0) { +		num += 8; +		word >>= 8; +	} +	if ((word & 0xf) == 0) { +		num += 4; +		word >>= 4; +	} +	if ((word & 0x3) == 0) { +		num += 2; +		word >>= 2; +	} +	if ((word & 0x1) == 0) +		num += 1; +	return num; +} + +/* + * Find the first set bit in a memory region. + */ +static inline unsigned long +find_first_bit(const unsigned long *addr, unsigned long size) +{ +	const unsigned long *p = addr; +	unsigned long result = 0; +	unsigned long tmp; + +	while (size & ~(BITS_PER_LONG-1)) { +		if ((tmp = *(p++))) +			goto found; +		result += BITS_PER_LONG; +		size -= BITS_PER_LONG; +	} +	if (!size) +		return result; + +	tmp = (*p) & (~0UL >> (BITS_PER_LONG - size)); +	if (tmp == 0UL)		/* Are any bits set? */ +		return result + size;	/* Nope. */ +found: +	return result + __ffs(tmp); +} + +/* + * Find the next set bit in a memory region. + */ +static inline unsigned long +find_next_bit(const unsigned long *addr, unsigned long size, unsigned long offset) +{ +	const unsigned long *p = addr + BITOP_WORD(offset); +	unsigned long result = offset & ~(BITS_PER_LONG-1); +	unsigned long tmp; + +	if (offset >= size) +		return size; +	size -= result; +	offset %= BITS_PER_LONG; +	if (offset) { +		tmp = *(p++); +		tmp &= (~0UL << offset); +		if (size < BITS_PER_LONG) +			goto found_first; +		if (tmp) +			goto found_middle; +		size -= BITS_PER_LONG; +		result += BITS_PER_LONG; +	} +	while (size & ~(BITS_PER_LONG-1)) { +		if ((tmp = *(p++))) +			goto found_middle; +		result += BITS_PER_LONG; +		size -= BITS_PER_LONG; +	} +	if (!size) +		return result; +	tmp = *p; + +found_first: +	tmp &= (~0UL >> (BITS_PER_LONG - size)); +	if (tmp == 0UL)		/* Are any bits set? */ +		return result + size;	/* Nope. */ +found_middle: +	return result + __ffs(tmp); +} +  #endif  |