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

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
......@@ -121,8 +121,11 @@ static inline void local_irq_disable(void)
#define nop() __asm__ __volatile__ ("nop" : : )
#define xchg(ptr,x) \
((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
#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);
......@@ -146,7 +149,7 @@ extern void __xchg_called_with_bad_pointer(void);
#endif /* CONFIG_CHIP_M32700_TS1 */
static __always_inline unsigned long
__xchg(unsigned long x, volatile void * ptr, int size)
__xchg(unsigned long x, volatile void *ptr, int size)
{
unsigned long flags;
unsigned long tmp = 0;
......@@ -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);
......@@ -247,13 +317,34 @@ __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
return old;
}
#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))); \
})
#define cmpxchg(ptr, o, n) \
((__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__ */
......
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