Commit 2cf8d82d authored by Andrew Morton's avatar Andrew Morton Committed by Linus Torvalds
Browse files

[PATCH] make local_t signed 



local_t's were defined to be unsigned.  This increases confusion because
atomic_t's are signed.  The patch goes through and changes all implementations
to use signed longs throughout.

Also, x86-64 was using 32-bit quantities for the value passed into local_add()
and local_sub().  Fixed.

All (actually, both) existing users have been audited.

(Also s/__inline__/inline/ in x86_64/local.h)

Cc: Andi Kleen <ak@muc.de>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Kyle McMartin <kyle@parisc-linux.org>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 09ce3512

include/asm-generic/local.h

+10 −3
Original line number Diff line number Diff line
@@ -7,8 +7,15 @@ 
#include <asm/atomic.h>

#include <asm/types.h>



/* An unsigned long type for operations which are atomic for a single

 * CPU.  Usually used in combination with per-cpu variables. */

/*

 * A signed long type for operations which are atomic for a single CPU.

 * Usually used in combination with per-cpu variables.

 *

 * This is the default implementation, which uses atomic_long_t.  Which is

 * rather pointless.  The whole point behind local_t is that some processors

 * can perform atomic adds and subtracts in a manner which is atomic wrt IRQs

 * running on this CPU.  local_t allows exploitation of such capabilities.

 */



/* Implement in terms of atomics. */
@@ -20,7 +27,7 @@ typedef struct 


#define LOCAL_INIT(i)	{ ATOMIC_LONG_INIT(i) }



#define local_read(l)	((unsigned long)atomic_long_read(&(l)->a))

#define local_read(l)	atomic_long_read(&(l)->a)

#define local_set(l,i)	atomic_long_set((&(l)->a),(i))

#define local_inc(l)	atomic_long_inc(&(l)->a)

#define local_dec(l)	atomic_long_dec(&(l)->a)

include/asm-i386/local.h

+3 −3
Original line number Diff line number Diff line
@@ -5,7 +5,7 @@ 


typedef struct

{

	volatile unsigned long counter;

	volatile long counter;

} local_t;



#define LOCAL_INIT(i)	{ (i) }
@@ -29,7 +29,7 @@ static __inline__ void local_dec(local_t *v) 
		:"m" (v->counter));

}



static __inline__ void local_add(unsigned long i, local_t *v)

static __inline__ void local_add(long i, local_t *v)

{

	__asm__ __volatile__(

		"addl %1,%0"
@@ -37,7 +37,7 @@ static __inline__ void local_add(unsigned long i, local_t *v) 
		:"ir" (i), "m" (v->counter));

}



static __inline__ void local_sub(unsigned long i, local_t *v)

static __inline__ void local_sub(long i, local_t *v)

{

	__asm__ __volatile__(

		"subl %1,%0"

include/asm-x86_64/local.h

+5 −5
Original line number Diff line number Diff line
@@ -5,7 +5,7 @@ 


typedef struct

{

	volatile unsigned long counter;

	volatile long counter;

} local_t;



#define LOCAL_INIT(i)	{ (i) }
@@ -13,7 +13,7 @@ typedef struct 
#define local_read(v)	((v)->counter)

#define local_set(v,i)	(((v)->counter) = (i))



static __inline__ void local_inc(local_t *v)

static inline void local_inc(local_t *v)

{

	__asm__ __volatile__(

		"incq %0"
@@ -21,7 +21,7 @@ static __inline__ void local_inc(local_t *v) 
		:"m" (v->counter));

}



static __inline__ void local_dec(local_t *v)

static inline void local_dec(local_t *v)

{

	__asm__ __volatile__(

		"decq %0"
@@ -29,7 +29,7 @@ static __inline__ void local_dec(local_t *v) 
		:"m" (v->counter));

}



static __inline__ void local_add(unsigned int i, local_t *v)

static inline void local_add(long i, local_t *v)

{

	__asm__ __volatile__(

		"addq %1,%0"
@@ -37,7 +37,7 @@ static __inline__ void local_add(unsigned int i, local_t *v) 
		:"ir" (i), "m" (v->counter));

}



static __inline__ void local_sub(unsigned int i, local_t *v)

static inline void local_sub(long i, local_t *v)

{

	__asm__ __volatile__(

		"subq %1,%0"

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