lib: rename lib/find_next_bit.c to lib/find_bit.c
authorYury Norov <yury.norov@gmail.com>
Thu, 16 Apr 2015 19:43:19 +0000 (12:43 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 17 Apr 2015 13:03:54 +0000 (09:03 -0400)
This file contains implementation for all find_*_bit{,_le}
So giving it more generic name looks reasonable.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
lib/Makefile
lib/find_bit.c [new file with mode: 0644]
lib/find_next_bit.c [deleted file]

index 05f8fa56a1bcdbaf3e305a25090fa831773f5b09..da6116b21555583864e2eadd7ae5615d46878d84 100644 (file)
@@ -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 (file)
index 0000000..18072ea
--- /dev/null
@@ -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 <rusty@rustcorp.com.au>
+ * (Inspired by David Howell's find_next_bit implementation)
+ *
+ * Rewritten by Yury Norov <yury.norov@gmail.com> 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 <linux/bitops.h>
+#include <linux/bitmap.h>
+#include <linux/export.h>
+#include <linux/kernel.h>
+
+#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 (file)
index 18072ea..0000000
+++ /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 <rusty@rustcorp.com.au>
- * (Inspired by David Howell's find_next_bit implementation)
- *
- * Rewritten by Yury Norov <yury.norov@gmail.com> 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 <linux/bitops.h>
-#include <linux/bitmap.h>
-#include <linux/export.h>
-#include <linux/kernel.h>
-
-#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 */