Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 7b631c2d authored by Mathieu Desnoyers's avatar Mathieu Desnoyers Committed by Linus Torvalds
Browse files

New cmpxchg_local (optimized for UP case) for m32r 



Add __xchg_local, xchg_local (define), __cmpxchg_local_u32, __cmpxchg_local,
cmpxchg_local(macro).

cmpxchg_local and cmpxchg64_local will use the architecture specific
__cmpxchg_local_u32 for 32 bits arguments, and use the generic
__cmpxchg_local_generic for 8, 16 and 64 bits arguments.

Signed-off-by: default avatarMathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: default avatarHirokazu Takata <takata@linux-m32r.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 4b78fff6

include/asm-m32r/system.h

+101 −10
Original line number Diff line number Diff line
@@ -123,6 +123,9 @@ static inline void local_irq_disable(void) 


#define xchg(ptr, x)							\

	((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))

#define xchg_local(ptr, x)						\

	((__typeof__(*(ptr)))__xchg_local((unsigned long)(x), (ptr),	\

			sizeof(*(ptr))))



#ifdef CONFIG_SMP

extern void  __xchg_called_with_bad_pointer(void);
@@ -196,6 +199,42 @@ __xchg(unsigned long x, volatile void * ptr, int size) 
	return (tmp);

}



static __always_inline unsigned long

__xchg_local(unsigned long x, volatile void *ptr, int size)

{

	unsigned long flags;

	unsigned long tmp = 0;



	local_irq_save(flags);



	switch (size) {

	case 1:

		__asm__ __volatile__ (

			"ldb	%0, @%2 \n\t"

			"stb	%1, @%2 \n\t"

			: "=&r" (tmp) : "r" (x), "r" (ptr) : "memory");

		break;

	case 2:

		__asm__ __volatile__ (

			"ldh	%0, @%2 \n\t"

			"sth	%1, @%2 \n\t"

			: "=&r" (tmp) : "r" (x), "r" (ptr) : "memory");

		break;

	case 4:

		__asm__ __volatile__ (

			"ld	%0, @%2 \n\t"

			"st	%1, @%2 \n\t"

			: "=&r" (tmp) : "r" (x), "r" (ptr) : "memory");

		break;

	default:

		__xchg_called_with_bad_pointer();

	}



	local_irq_restore(flags);



	return (tmp);

}



#define __HAVE_ARCH_CMPXCHG	1



static inline unsigned long
@@ -228,6 +267,37 @@ __cmpxchg_u32(volatile unsigned int *p, unsigned int old, unsigned int new) 
	return retval;

}



static inline unsigned long

__cmpxchg_local_u32(volatile unsigned int *p, unsigned int old,

			unsigned int new)

{

	unsigned long flags;

	unsigned int retval;



	local_irq_save(flags);

	__asm__ __volatile__ (

			DCACHE_CLEAR("%0", "r4", "%1")

			"ld %0, @%1;		\n"

		"	bne	%0, %2, 1f;	\n"

			"st %3, @%1;		\n"

		"	bra	2f;		\n"

		"       .fillinsn		\n"

		"1:"

			"st %0, @%1;		\n"

		"       .fillinsn		\n"

		"2:"

			: "=&r" (retval)

			: "r" (p), "r" (old), "r" (new)

			: "cbit", "memory"

#ifdef CONFIG_CHIP_M32700_TS1

			, "r4"

#endif  /* CONFIG_CHIP_M32700_TS1 */

		);

	local_irq_restore(flags);



	return retval;

}



/* This function doesn't exist, so you'll get a linker error

   if something tries to do an invalid cmpxchg().  */

extern void __cmpxchg_called_with_bad_pointer(void);
@@ -248,12 +318,33 @@ __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size) 
}



#define cmpxchg(ptr, o, n)						 \

  ({									 \

     __typeof__(*(ptr)) _o_ = (o);					 \

     __typeof__(*(ptr)) _n_ = (n);					 \

     (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,		 \

				    (unsigned long)_n_, sizeof(*(ptr))); \

  })

	((__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)(o),	 \

			(unsigned long)(n), sizeof(*(ptr))))



#include <asm-generic/cmpxchg-local.h>



static inline unsigned long __cmpxchg_local(volatile void *ptr,

				      unsigned long old,

				      unsigned long new, int size)

{

	switch (size) {

	case 4:

		return __cmpxchg_local_u32(ptr, old, new);

	default:

		return __cmpxchg_local_generic(ptr, old, new, size);

	}



	return old;

}



/*

 * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make

 * them available.

 */

#define cmpxchg_local(ptr, o, n)				  	    \

	((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o),	    \

			(unsigned long)(n), sizeof(*(ptr))))

#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))



#endif  /* __KERNEL__ */