From 840620a1596a90636a44d6a593db4041bb28d52e Mon Sep 17 00:00:00 2001 From: Yury Norov Date: Thu, 16 Apr 2015 12:43:19 -0700 Subject: lib: rename lib/find_next_bit.c to lib/find_bit.c This file contains implementation for all find_*_bit{,_le} So giving it more generic name looks reasonable. Signed-off-by: Yury Norov Reviewed-by: Rasmus Villemoes Reviewed-by: George Spelvin Cc: Alexey Klimov Cc: David S. Miller Cc: Daniel Borkmann Cc: Hannes Frederic Sowa Cc: Lai Jiangshan Cc: Mark Salter Cc: AKASHI Takahiro Cc: Thomas Graf Cc: Valentin Rothberg Cc: Chris Wilson Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/Makefile | 2 +- lib/find_bit.c | 193 ++++++++++++++++++++++++++++++++++++++++++++++++++++ lib/find_next_bit.c | 193 ---------------------------------------------------- 3 files changed, 194 insertions(+), 194 deletions(-) create mode 100644 lib/find_bit.c delete mode 100644 lib/find_next_bit.c diff --git a/lib/Makefile b/lib/Makefile index 05f8fa56a1bc..da6116b21555 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -25,7 +25,7 @@ obj-y += lockref.o obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \ bust_spinlocks.o kasprintf.o bitmap.o scatterlist.o \ gcd.o lcm.o list_sort.o uuid.o flex_array.o iov_iter.o clz_ctz.o \ - bsearch.o find_next_bit.o llist.o memweight.o kfifo.o \ + bsearch.o find_bit.o llist.o memweight.o kfifo.o \ percpu-refcount.o percpu_ida.o rhashtable.o reciprocal_div.o obj-y += string_helpers.o obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o diff --git a/lib/find_bit.c b/lib/find_bit.c new file mode 100644 index 000000000000..18072ea9c20e --- /dev/null +++ b/lib/find_bit.c @@ -0,0 +1,193 @@ +/* bit search implementation + * + * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * Copyright (C) 2008 IBM Corporation + * 'find_last_bit' is written by Rusty Russell + * (Inspired by David Howell's find_next_bit implementation) + * + * Rewritten by Yury Norov to decrease + * size and improve performance, 2015. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include +#include +#include +#include + +#if !defined(find_next_bit) || !defined(find_next_zero_bit) + +/* + * This is a common helper function for find_next_bit and + * find_next_zero_bit. The difference is the "invert" argument, which + * is XORed with each fetched word before searching it for one bits. + */ +static unsigned long _find_next_bit(const unsigned long *addr, + unsigned long nbits, unsigned long start, unsigned long invert) +{ + unsigned long tmp; + + if (!nbits || start >= nbits) + return nbits; + + tmp = addr[start / BITS_PER_LONG] ^ invert; + + /* Handle 1st word. */ + tmp &= BITMAP_FIRST_WORD_MASK(start); + start = round_down(start, BITS_PER_LONG); + + while (!tmp) { + start += BITS_PER_LONG; + if (start >= nbits) + return nbits; + + tmp = addr[start / BITS_PER_LONG] ^ invert; + } + + return min(start + __ffs(tmp), nbits); +} +#endif + +#ifndef find_next_bit +/* + * Find the next set bit in a memory region. + */ +unsigned long find_next_bit(const unsigned long *addr, unsigned long size, + unsigned long offset) +{ + return _find_next_bit(addr, size, offset, 0UL); +} +EXPORT_SYMBOL(find_next_bit); +#endif + +#ifndef find_next_zero_bit +unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size, + unsigned long offset) +{ + return _find_next_bit(addr, size, offset, ~0UL); +} +EXPORT_SYMBOL(find_next_zero_bit); +#endif + +#ifndef 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 idx; + + for (idx = 0; idx * BITS_PER_LONG < size; idx++) { + if (addr[idx]) + return min(idx * BITS_PER_LONG + __ffs(addr[idx]), size); + } + + return size; +} +EXPORT_SYMBOL(find_first_bit); +#endif + +#ifndef find_first_zero_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 idx; + + for (idx = 0; idx * BITS_PER_LONG < size; idx++) { + if (addr[idx] != ~0UL) + return min(idx * BITS_PER_LONG + ffz(addr[idx]), size); + } + + return size; +} +EXPORT_SYMBOL(find_first_zero_bit); +#endif + +#ifndef find_last_bit +unsigned long find_last_bit(const unsigned long *addr, unsigned long size) +{ + if (size) { + unsigned long val = BITMAP_LAST_WORD_MASK(size); + unsigned long idx = (size-1) / BITS_PER_LONG; + + do { + val &= addr[idx]; + if (val) + return idx * BITS_PER_LONG + __fls(val); + + val = ~0ul; + } while (idx--); + } + return size; +} +EXPORT_SYMBOL(find_last_bit); +#endif + +#ifdef __BIG_ENDIAN + +/* include/linux/byteorder does not support "unsigned long" type */ +static inline unsigned long ext2_swab(const unsigned long y) +{ +#if BITS_PER_LONG == 64 + return (unsigned long) __swab64((u64) y); +#elif BITS_PER_LONG == 32 + return (unsigned long) __swab32((u32) y); +#else +#error BITS_PER_LONG not defined +#endif +} + +#if !defined(find_next_bit_le) || !defined(find_next_zero_bit_le) +static unsigned long _find_next_bit_le(const unsigned long *addr, + unsigned long nbits, unsigned long start, unsigned long invert) +{ + unsigned long tmp; + + if (!nbits || start >= nbits) + return nbits; + + tmp = addr[start / BITS_PER_LONG] ^ invert; + + /* Handle 1st word. */ + tmp &= ext2_swab(BITMAP_FIRST_WORD_MASK(start)); + start = round_down(start, BITS_PER_LONG); + + while (!tmp) { + start += BITS_PER_LONG; + if (start >= nbits) + return nbits; + + tmp = addr[start / BITS_PER_LONG] ^ invert; + } + + return min(start + __ffs(ext2_swab(tmp)), nbits); +} +#endif + +#ifndef find_next_zero_bit_le +unsigned long find_next_zero_bit_le(const void *addr, unsigned + long size, unsigned long offset) +{ + return _find_next_bit_le(addr, size, offset, ~0UL); +} +EXPORT_SYMBOL(find_next_zero_bit_le); +#endif + +#ifndef find_next_bit_le +unsigned long find_next_bit_le(const void *addr, unsigned + long size, unsigned long offset) +{ + return _find_next_bit_le(addr, size, offset, 0UL); +} +EXPORT_SYMBOL(find_next_bit_le); +#endif + +#endif /* __BIG_ENDIAN */ diff --git a/lib/find_next_bit.c b/lib/find_next_bit.c deleted file mode 100644 index 18072ea9c20e..000000000000 --- a/lib/find_next_bit.c +++ /dev/null @@ -1,193 +0,0 @@ -/* bit search implementation - * - * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - * - * Copyright (C) 2008 IBM Corporation - * 'find_last_bit' is written by Rusty Russell - * (Inspired by David Howell's find_next_bit implementation) - * - * Rewritten by Yury Norov to decrease - * size and improve performance, 2015. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - */ - -#include -#include -#include -#include - -#if !defined(find_next_bit) || !defined(find_next_zero_bit) - -/* - * This is a common helper function for find_next_bit and - * find_next_zero_bit. The difference is the "invert" argument, which - * is XORed with each fetched word before searching it for one bits. - */ -static unsigned long _find_next_bit(const unsigned long *addr, - unsigned long nbits, unsigned long start, unsigned long invert) -{ - unsigned long tmp; - - if (!nbits || start >= nbits) - return nbits; - - tmp = addr[start / BITS_PER_LONG] ^ invert; - - /* Handle 1st word. */ - tmp &= BITMAP_FIRST_WORD_MASK(start); - start = round_down(start, BITS_PER_LONG); - - while (!tmp) { - start += BITS_PER_LONG; - if (start >= nbits) - return nbits; - - tmp = addr[start / BITS_PER_LONG] ^ invert; - } - - return min(start + __ffs(tmp), nbits); -} -#endif - -#ifndef find_next_bit -/* - * Find the next set bit in a memory region. - */ -unsigned long find_next_bit(const unsigned long *addr, unsigned long size, - unsigned long offset) -{ - return _find_next_bit(addr, size, offset, 0UL); -} -EXPORT_SYMBOL(find_next_bit); -#endif - -#ifndef find_next_zero_bit -unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size, - unsigned long offset) -{ - return _find_next_bit(addr, size, offset, ~0UL); -} -EXPORT_SYMBOL(find_next_zero_bit); -#endif - -#ifndef 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 idx; - - for (idx = 0; idx * BITS_PER_LONG < size; idx++) { - if (addr[idx]) - return min(idx * BITS_PER_LONG + __ffs(addr[idx]), size); - } - - return size; -} -EXPORT_SYMBOL(find_first_bit); -#endif - -#ifndef find_first_zero_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 idx; - - for (idx = 0; idx * BITS_PER_LONG < size; idx++) { - if (addr[idx] != ~0UL) - return min(idx * BITS_PER_LONG + ffz(addr[idx]), size); - } - - return size; -} -EXPORT_SYMBOL(find_first_zero_bit); -#endif - -#ifndef find_last_bit -unsigned long find_last_bit(const unsigned long *addr, unsigned long size) -{ - if (size) { - unsigned long val = BITMAP_LAST_WORD_MASK(size); - unsigned long idx = (size-1) / BITS_PER_LONG; - - do { - val &= addr[idx]; - if (val) - return idx * BITS_PER_LONG + __fls(val); - - val = ~0ul; - } while (idx--); - } - return size; -} -EXPORT_SYMBOL(find_last_bit); -#endif - -#ifdef __BIG_ENDIAN - -/* include/linux/byteorder does not support "unsigned long" type */ -static inline unsigned long ext2_swab(const unsigned long y) -{ -#if BITS_PER_LONG == 64 - return (unsigned long) __swab64((u64) y); -#elif BITS_PER_LONG == 32 - return (unsigned long) __swab32((u32) y); -#else -#error BITS_PER_LONG not defined -#endif -} - -#if !defined(find_next_bit_le) || !defined(find_next_zero_bit_le) -static unsigned long _find_next_bit_le(const unsigned long *addr, - unsigned long nbits, unsigned long start, unsigned long invert) -{ - unsigned long tmp; - - if (!nbits || start >= nbits) - return nbits; - - tmp = addr[start / BITS_PER_LONG] ^ invert; - - /* Handle 1st word. */ - tmp &= ext2_swab(BITMAP_FIRST_WORD_MASK(start)); - start = round_down(start, BITS_PER_LONG); - - while (!tmp) { - start += BITS_PER_LONG; - if (start >= nbits) - return nbits; - - tmp = addr[start / BITS_PER_LONG] ^ invert; - } - - return min(start + __ffs(ext2_swab(tmp)), nbits); -} -#endif - -#ifndef find_next_zero_bit_le -unsigned long find_next_zero_bit_le(const void *addr, unsigned - long size, unsigned long offset) -{ - return _find_next_bit_le(addr, size, offset, ~0UL); -} -EXPORT_SYMBOL(find_next_zero_bit_le); -#endif - -#ifndef find_next_bit_le -unsigned long find_next_bit_le(const void *addr, unsigned - long size, unsigned long offset) -{ - return _find_next_bit_le(addr, size, offset, 0UL); -} -EXPORT_SYMBOL(find_next_bit_le); -#endif - -#endif /* __BIG_ENDIAN */ -- cgit v1.2.3