[PATCH 1/2] bitops: make asm-generic/bitops/find.h more generic

[PATCH 1/2] bitops: make asm-generic/bitops/find.h more generic

[Akinobu Mita]

asm-generic/bitops/find.h has the extern declarations of find_next_bit()
and find_next_zero_bit() and the macro definitions of find_first_bit()
and find_first_zero_bit(). It is only usable by the architectures which
enables CONFIG_GENERIC_FIND_NEXT_BIT and disables
CONFIG_GENERIC_FIND_FIRST_BIT.

x86 and tile enable both CONFIG_GENERIC_FIND_NEXT_BIT and
CONFIG_GENERIC_FIND_FIRST_BIT. These architectures cannot include
asm-generic/bitops/find.h in their asm/bitops.h. So ifdefed extern
declarations of find_first_bit and find_first_zero_bit() are put in
linux/bitops.h.

This makes asm-generic/bitops/find.h usable by these architectures
and use it. Also this change is needed for the forthcoming duplicated
extern declarations cleanup.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Chris Metcalf <cmetcalf@tilera.com>
---
 arch/tile/include/asm/bitops.h    |    1 +
 arch/x86/include/asm/bitops.h     |    2 ++
 include/asm-generic/bitops/find.h |   25 +++++++++++++++++++++++++
 include/linux/bitops.h            |   22 ----------------------
 4 files changed, 28 insertions(+), 22 deletions(-)

diff --git a/arch/tile/include/asm/bitops.h b/arch/tile/include/asm/bitops.h
index 6832b4b..6d4f0ff 100644
--- a/arch/tile/include/asm/bitops.h
+++ b/arch/tile/include/asm/bitops.h
@@ -120,6 +120,7 @@ static inline unsigned long __arch_hweight64(__u64 w)
 
 #include <asm-generic/bitops/const_hweight.h>
 #include <asm-generic/bitops/lock.h>
+#include <asm-generic/bitops/find.h>
 #include <asm-generic/bitops/sched.h>
 #include <asm-generic/bitops/ext2-non-atomic.h>
 #include <asm-generic/bitops/minix.h>
diff --git a/arch/x86/include/asm/bitops.h b/arch/x86/include/asm/bitops.h
index bafd80d..903683b 100644
--- a/arch/x86/include/asm/bitops.h
+++ b/arch/x86/include/asm/bitops.h
@@ -440,6 +440,8 @@ static inline int fls(int x)
 
 #ifdef __KERNEL__
 
+#include <asm-generic/bitops/find.h>
+
 #include <asm-generic/bitops/sched.h>
 
 #define ARCH_HAS_FAST_MULTIPLIER 1
diff --git a/include/asm-generic/bitops/find.h b/include/asm-generic/bitops/find.h
index 1914e97..30afec0 100644
--- a/include/asm-generic/bitops/find.h
+++ b/include/asm-generic/bitops/find.h
@@ -9,7 +9,32 @@ extern unsigned long find_next_zero_bit(const unsigned long *addr, unsigned
 		long size, unsigned long offset);
 #endif
 
+#ifdef CONFIG_GENERIC_FIND_FIRST_BIT
+
+/**
+ * find_first_bit - find the first set bit in a memory region
+ * @addr: The address to start the search at
+ * @size: The maximum size to search
+ *
+ * Returns the bit number of the first set bit.
+ */
+extern unsigned long find_first_bit(const unsigned long *addr,
+				    unsigned long size);
+
+/**
+ * find_first_zero_bit - find the first cleared bit in a memory region
+ * @addr: The address to start the search at
+ * @size: The maximum size to search
+ *
+ * Returns the bit number of the first cleared bit.
+ */
+extern unsigned long find_first_zero_bit(const unsigned long *addr,
+					 unsigned long size);
+#else /* CONFIG_GENERIC_FIND_FIRST_BIT */
+
 #define find_first_bit(addr, size) find_next_bit((addr), (size), 0)
 #define find_first_zero_bit(addr, size) find_next_zero_bit((addr), (size), 0)
 
+#endif /* CONFIG_GENERIC_FIND_FIRST_BIT */
+
 #endif /*_ASM_GENERIC_BITOPS_FIND_H_ */
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index fc68053..adb0f11 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -136,28 +136,6 @@ static inline unsigned long __ffs64(u64 word)
 }
 
 #ifdef __KERNEL__
-#ifdef CONFIG_GENERIC_FIND_FIRST_BIT
-
-/**
- * find_first_bit - find the first set bit in a memory region
- * @addr: The address to start the search at
- * @size: The maximum size to search
- *
- * Returns the bit number of the first set bit.
- */
-extern unsigned long find_first_bit(const unsigned long *addr,
-				    unsigned long size);
-
-/**
- * find_first_zero_bit - find the first cleared bit in a memory region
- * @addr: The address to start the search at
- * @size: The maximum size to search
- *
- * Returns the bit number of the first cleared bit.
- */
-extern unsigned long find_first_zero_bit(const unsigned long *addr,
-					 unsigned long size);
-#endif /* CONFIG_GENERIC_FIND_FIRST_BIT */
 
 #ifdef CONFIG_GENERIC_FIND_LAST_BIT
 /**
-- 
1.7.1.231.gd0b16

[PATCH 2/2] bitops: remove duplicated extern declarations

[Akinobu Mita]

If CONFIG_GENERIC_FIND_NEXT_BIT is enabled, find_next_bit() and
find_next_zero_bit() are doubly declared in asm-generic/bitops/find.h
and linux/bitops.h.

asm/bitops.h includes asm-generic/bitops/find.h if and only if the
architecture enables CONFIG_GENERIC_FIND_NEXT_BIT. And asm/bitops.h
is included by linux/bitops.h

So we can just remove the extern declarations of find_next_bit() and
find_next_zero_bit() in linux/bitops.h.

Also we can remove unneeded #ifndef CONFIG_GENERIC_FIND_NEXT_BIT in
asm-generic/bitops/find.h.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
---
 include/asm-generic/bitops/find.h |   14 ++++++++++++--
 include/linux/bitops.h            |   23 -----------------------
 2 files changed, 12 insertions(+), 25 deletions(-)

diff --git a/include/asm-generic/bitops/find.h b/include/asm-generic/bitops/find.h
index 30afec0..110fa70 100644
--- a/include/asm-generic/bitops/find.h
+++ b/include/asm-generic/bitops/find.h
@@ -1,13 +1,23 @@
 #ifndef _ASM_GENERIC_BITOPS_FIND_H_
 #define _ASM_GENERIC_BITOPS_FIND_H_
 
-#ifndef CONFIG_GENERIC_FIND_NEXT_BIT
+/**
+ * find_next_bit - find the next set bit in a memory region
+ * @addr: The address to base the search on
+ * @offset: The bitnumber to start searching at
+ * @size: The bitmap size in bits
+ */
 extern unsigned long find_next_bit(const unsigned long *addr, unsigned long
 		size, unsigned long offset);
 
+/**
+ * find_next_zero_bit - find the next cleared bit in a memory region
+ * @addr: The address to base the search on
+ * @offset: The bitnumber to start searching at
+ * @size: The bitmap size in bits
+ */
 extern unsigned long find_next_zero_bit(const unsigned long *addr, unsigned
 		long size, unsigned long offset);
-#endif
 
 #ifdef CONFIG_GENERIC_FIND_FIRST_BIT
 
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index adb0f11..827cc95 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -149,28 +149,5 @@ extern unsigned long find_last_bit(const unsigned long *addr,
 				   unsigned long size);
 #endif /* CONFIG_GENERIC_FIND_LAST_BIT */
 
-#ifdef CONFIG_GENERIC_FIND_NEXT_BIT
-
-/**
- * find_next_bit - find the next set bit in a memory region
- * @addr: The address to base the search on
- * @offset: The bitnumber to start searching at
- * @size: The bitmap size in bits
- */
-extern unsigned long find_next_bit(const unsigned long *addr,
-				   unsigned long size, unsigned long offset);
-
-/**
- * find_next_zero_bit - find the next cleared bit in a memory region
- * @addr: The address to base the search on
- * @offset: The bitnumber to start searching at
- * @size: The bitmap size in bits
- */
-
-extern unsigned long find_next_zero_bit(const unsigned long *addr,
-					unsigned long size,
-					unsigned long offset);
-
-#endif /* CONFIG_GENERIC_FIND_NEXT_BIT */
 #endif /* __KERNEL__ */
 #endif
-- 
1.7.1.231.gd0b16

Re: [PATCH 1/2] bitops: make asm-generic/bitops/find.h more generic

[Chris Metcalf]

 On 9/29/2010 5:08 AM, Akinobu Mita wrote:
> asm-generic/bitops/find.h has the extern declarations of find_next_bit()
> and find_next_zero_bit() and the macro definitions of find_first_bit()
> and find_first_zero_bit(). It is only usable by the architectures which
> enables CONFIG_GENERIC_FIND_NEXT_BIT and disables
> CONFIG_GENERIC_FIND_FIRST_BIT.
>
> x86 and tile enable both CONFIG_GENERIC_FIND_NEXT_BIT and
> CONFIG_GENERIC_FIND_FIRST_BIT. These architectures cannot include
> asm-generic/bitops/find.h in their asm/bitops.h. So ifdefed extern
> declarations of find_first_bit and find_first_zero_bit() are put in
> linux/bitops.h.
>
> This makes asm-generic/bitops/find.h usable by these architectures
> and use it. Also this change is needed for the forthcoming duplicated
> extern declarations cleanup.

This looks good, thanks.

Acked-by: Chris Metcalf <cmetcalf@tilera.com>

-- 
Chris Metcalf, Tilera Corp.
http://www.tilera.com