linux-kernel - [PATCH 2/2] lib/bitmap.c: Elide bitmap_copy

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Date:	Wed, 31 Dec 2014 03:13:32 +0100
From:	Rasmus Villemoes <linux@...musvillemoes.dk>
To:	Andrew Morton <akpm@...ux-foundation.org>
Cc:	Rasmus Villemoes <linux@...musvillemoes.dk>,
	linux-kernel@...r.kernel.org
Subject: [PATCH 2/2] lib/bitmap.c: Elide bitmap_copy_le on little-endian

On little-endian, there's no reason to have an extra, presumably less
efficient, way of copying a bitmap.

Signed-off-by: Rasmus Villemoes <linux@...musvillemoes.dk>
---
 include/linux/bitmap.h | 4 ++++
 lib/bitmap.c           | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index bd1748919872..a1977e153e63 100644
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -170,7 +170,11 @@ extern void bitmap_fold(unsigned long *dst, const unsigned long *orig,
 extern int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order);
 extern void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order);
 extern int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order);
+#ifdef __BIG_ENDIAN
 extern void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits);
+#else
+#define bitmap_copy_le bitmap_copy
+#endif
 extern int bitmap_ord_to_pos(const unsigned long *bitmap, int n, int bits);
 extern int bitmap_print_to_pagebuf(bool list, char *buf,
 				   const unsigned long *maskp, int nmaskbits);
diff --git a/lib/bitmap.c b/lib/bitmap.c
index 5ded9180528b..8014996b1531 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -1207,6 +1207,7 @@ EXPORT_SYMBOL(bitmap_allocate_region);
  *
  * Require nbits % BITS_PER_LONG == 0.
  */
+#ifdef __BIG_ENDIAN
 void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits)
 {
 	unsigned int i;
@@ -1219,3 +1220,4 @@ void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int n
 	}
 }
 EXPORT_SYMBOL(bitmap_copy_le);
+#endif
-- 
2.1.3

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