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: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/asm-m32r/system.h b/include/asm-m32r/system.h
index 2365de5..7e7eb37 100644
--- a/include/asm-m32r/system.h
+++ b/include/asm-m32r/system.h
@@ -121,8 +121,11 @@
#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 @@
#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 @@
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 @@
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 @@
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__ */