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bitops: remove "optimizations"

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The mapsize optimizations which were moved from x86 to the generic
code in commit 64970b68d2 increased the
binary size on non x86 architectures.

Looking into the real effects of the "optimizations" it turned out
that they are not used in find_next_bit() and find_next_zero_bit().

The ones in find_first_bit() and find_first_zero_bit() are used in a
couple of places but none of them is a real hot path.

Remove the "optimizations" all together and call the library functions
unconditionally.

Boot-tested on x86 and compile tested on every cross compiler I have.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Thomas Gleixner 2008-04-29 12:01:02 +02:00 • committed by Linus Torvalds
parent 8972331292
commit fee4b19fb3
2 changed files with 19 additions and 112 deletions
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22
lib/find_next_bit.c
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@ -20,8 +20,8 @@
/*
* Find the next set bit in a memory region.
*/
unsigned long __find_next_bit(const unsigned long *addr,
unsigned long size, unsigned long offset)
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);
@ -58,14 +58,14 @@ found_first:
found_middle:
return result + __ffs(tmp);
}
EXPORT_SYMBOL(__find_next_bit);
EXPORT_SYMBOL(find_next_bit);
/*
* This implementation of find_{first,next}_zero_bit was stolen from
* Linus' asm-alpha/bitops.h.
*/
unsigned long __find_next_zero_bit(const unsigned long *addr,
unsigned long size, unsigned long offset)
unsigned long find_next_zero_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);
@ -102,15 +102,14 @@ found_first:
found_middle:
return result + ffz(tmp);
}
EXPORT_SYMBOL(__find_next_zero_bit);
EXPORT_SYMBOL(find_next_zero_bit);
#endif /* CONFIG_GENERIC_FIND_NEXT_BIT */
#ifdef CONFIG_GENERIC_FIND_FIRST_BIT
/*
* Find the first set bit in a memory region.
*/
unsigned long __find_first_bit(const unsigned long *addr,
unsigned long size)
unsigned long find_first_bit(const unsigned long *addr, unsigned long size)
{
const unsigned long *p = addr;
unsigned long result = 0;
@ -131,13 +130,12 @@ unsigned long __find_first_bit(const unsigned long *addr,
found:
return result + __ffs(tmp);
}
EXPORT_SYMBOL(__find_first_bit);
EXPORT_SYMBOL(find_first_bit);
/*
* Find the first cleared bit in a memory region.
*/
unsigned long __find_first_zero_bit(const unsigned long *addr,
unsigned long size)
unsigned long find_first_zero_bit(const unsigned long *addr, unsigned long size)
{
const unsigned long *p = addr;
unsigned long result = 0;
@ -158,7 +156,7 @@ unsigned long __find_first_zero_bit(const unsigned long *addr,
found:
return result + ffz(tmp);
}
EXPORT_SYMBOL(__find_first_zero_bit);
EXPORT_SYMBOL(find_first_zero_bit);
#endif /* CONFIG_GENERIC_FIND_FIRST_BIT */
#ifdef __BIG_ENDIAN