lib/find_bit.c: join _find_next_bit{_le}

_find_next_bit and _find_next_bit_le are very similar functions.  It's
possible to join them by adding 1 parameter and a couple of simple
checks.  It's simplify maintenance and make possible to shrink the size
of .text by un-inlining the unified function (in the following patch).

Link: http://lkml.kernel.org/r/20200103202846.21616-2-yury.norov@gmail.com
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Cc: Allison Randal <allison@lohutok.net>
Cc: Joe Perches <joe@perches.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/lib/find_bit.c b/lib/find_bit.c
index 06e503c339f377bbe96d4929a317aed809295da1..c897c127316da2dc9bb97230ff94cb0ef74d080e 100644 (file)
--- a/lib/find_bit.c
+++ b/lib/find_bit.c
@@ -17,9 +17,9 @@
 #include <linux/export.h>
 #include <linux/kernel.h>
 
-#if !defined(find_next_bit) || !defined(find_next_zero_bit) || \
-               !defined(find_next_and_bit)
-
+#if !defined(find_next_bit) || !defined(find_next_zero_bit) ||                 \
+       !defined(find_next_bit_le) || !defined(find_next_zero_bit_le) ||        \
+       !defined(find_next_and_bit)
 /*
  * This is a common helper function for find_next_bit, find_next_zero_bit, and
  * find_next_and_bit. The differences are:
@@ -29,9 +29,9 @@
  */
 static inline unsigned long _find_next_bit(const unsigned long *addr1,
                const unsigned long *addr2, unsigned long nbits,
-               unsigned long start, unsigned long invert)
+               unsigned long start, unsigned long invert, unsigned long le)
 {
-       unsigned long tmp;
+       unsigned long tmp, mask;
 
        if (unlikely(start >= nbits))
                return nbits;
@@ -42,7 +42,12 @@ static inline unsigned long _find_next_bit(const unsigned long *addr1,
        tmp ^= invert;
 
        /* Handle 1st word. */
-       tmp &= BITMAP_FIRST_WORD_MASK(start);
+       mask = BITMAP_FIRST_WORD_MASK(start);
+       if (le)
+               mask = swab(mask);
+
+       tmp &= mask;
+
        start = round_down(start, BITS_PER_LONG);
 
        while (!tmp) {
@@ -56,6 +61,9 @@ static inline unsigned long _find_next_bit(const unsigned long *addr1,
                tmp ^= invert;
        }
 
+       if (le)
+               tmp = swab(tmp);
+
        return min(start + __ffs(tmp), nbits);
 }
 #endif
@@ -67,7 +75,7 @@ static inline unsigned long _find_next_bit(const unsigned long *addr1,
 unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
                            unsigned long offset)
 {
-       return _find_next_bit(addr, NULL, size, offset, 0UL);
+       return _find_next_bit(addr, NULL, size, offset, 0UL, 0);
 }
 EXPORT_SYMBOL(find_next_bit);
 #endif
@@ -76,7 +84,7 @@ EXPORT_SYMBOL(find_next_bit);
 unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
                                 unsigned long offset)
 {
-       return _find_next_bit(addr, NULL, size, offset, ~0UL);
+       return _find_next_bit(addr, NULL, size, offset, ~0UL, 0);
 }
 EXPORT_SYMBOL(find_next_zero_bit);
 #endif
@@ -86,7 +94,7 @@ unsigned long find_next_and_bit(const unsigned long *addr1,
                const unsigned long *addr2, unsigned long size,
                unsigned long offset)
 {
-       return _find_next_bit(addr1, addr2, size, offset, 0UL);
+       return _find_next_bit(addr1, addr2, size, offset, 0UL, 0);
 }
 EXPORT_SYMBOL(find_next_and_bit);
 #endif
@@ -149,45 +157,11 @@ EXPORT_SYMBOL(find_last_bit);
 
 #ifdef __BIG_ENDIAN
 
-#if !defined(find_next_bit_le) || !defined(find_next_zero_bit_le)
-static inline unsigned long _find_next_bit_le(const unsigned long *addr1,
-               const unsigned long *addr2, unsigned long nbits,
-               unsigned long start, unsigned long invert)
-{
-       unsigned long tmp;
-
-       if (unlikely(start >= nbits))
-               return nbits;
-
-       tmp = addr1[start / BITS_PER_LONG];
-       if (addr2)
-               tmp &= addr2[start / BITS_PER_LONG];
-       tmp ^= invert;
-
-       /* Handle 1st word. */
-       tmp &= 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 = addr1[start / BITS_PER_LONG];
-               if (addr2)
-                       tmp &= addr2[start / BITS_PER_LONG];
-               tmp ^= invert;
-       }
-
-       return min(start + __ffs(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, NULL, size, offset, ~0UL);
+       return _find_next_bit(addr, NULL, size, offset, ~0UL, 1);
 }
 EXPORT_SYMBOL(find_next_zero_bit_le);
 #endif
@@ -196,7 +170,7 @@ EXPORT_SYMBOL(find_next_zero_bit_le);
 unsigned long find_next_bit_le(const void *addr, unsigned
                long size, unsigned long offset)
 {
-       return _find_next_bit_le(addr, NULL, size, offset, 0UL);
+       return _find_next_bit(addr, NULL, size, offset, 0UL, 1);
 }
 EXPORT_SYMBOL(find_next_bit_le);
 #endif