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authorHirokazu Takata <takata@linux-m32r.org>2005-11-28 13:43:59 -0800
committerLinus Torvalds <torvalds@g5.osdl.org>2005-11-28 14:42:24 -0800
commit0332db5aff3eec73eead6d991782b0dee1376dc0 (patch)
treebc3299c3be9f5a64591dbe1a3ab5b86991c847b3 /include/asm-m32r
parent91f4ab056d85d23fa6955927fdeb1558673e8cd1 (diff)
[PATCH] m32r: Introduce atomic_cmpxchg and atomic_inc_not_zero operations
Introduce atomic_cmpxchg and atomic_inc_not_zero operations for m32r. Signed-off-by: Hayato Fujiwara <fujiwara@linux-m32r.org> Signed-off-by: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'include/asm-m32r')
-rw-r--r--include/asm-m32r/atomic.h21
-rw-r--r--include/asm-m32r/system.h64
2 files changed, 83 insertions, 2 deletions
diff --git a/include/asm-m32r/atomic.h b/include/asm-m32r/atomic.h
index bfff69a4993..ef1fb8ea472 100644
--- a/include/asm-m32r/atomic.h
+++ b/include/asm-m32r/atomic.h
@@ -242,6 +242,27 @@ static __inline__ int atomic_dec_return(atomic_t *v)
*/
#define atomic_add_negative(i,v) (atomic_add_return((i), (v)) < 0)
+#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
+
+/**
+ * atomic_add_unless - add unless the number is a given value
+ * @v: pointer of type atomic_t
+ * @a: the amount to add to v...
+ * @u: ...unless v is equal to u.
+ *
+ * Atomically adds @a to @v, so long as it was not @u.
+ * Returns non-zero if @v was not @u, and zero otherwise.
+ */
+#define atomic_add_unless(v, a, u) \
+({ \
+ int c, old; \
+ c = atomic_read(v); \
+ while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c) \
+ c = old; \
+ c != (u); \
+})
+#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+
static __inline__ void atomic_clear_mask(unsigned long mask, atomic_t *addr)
{
unsigned long flags;
diff --git a/include/asm-m32r/system.h b/include/asm-m32r/system.h
index 73348c3f858..5eee832b73a 100644
--- a/include/asm-m32r/system.h
+++ b/include/asm-m32r/system.h
@@ -11,6 +11,7 @@
*/
#include <linux/config.h>
+#include <asm/assembler.h>
#ifdef __KERNEL__
@@ -132,8 +133,6 @@ static inline void local_irq_disable(void)
!(flags & 0x40); \
})
-#endif /* __KERNEL__ */
-
#define nop() __asm__ __volatile__ ("nop" : : )
#define xchg(ptr,x) \
@@ -213,6 +212,67 @@ static __inline__ unsigned long __xchg(unsigned long x, volatile void * ptr,
return (tmp);
}
+#define __HAVE_ARCH_CMPXCHG 1
+
+static __inline__ unsigned long
+__cmpxchg_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")
+ M32R_LOCK" %0, @%1; \n"
+ " bne %0, %2, 1f; \n"
+ M32R_UNLOCK" %3, @%1; \n"
+ " bra 2f; \n"
+ " .fillinsn \n"
+ "1:"
+ M32R_UNLOCK" %2, @%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);
+
+static __inline__ unsigned long
+__cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
+{
+ switch (size) {
+ case 4:
+ return __cmpxchg_u32(ptr, old, new);
+#if 0 /* we don't have __cmpxchg_u64 */
+ case 8:
+ return __cmpxchg_u64(ptr, old, new);
+#endif /* 0 */
+ }
+ __cmpxchg_called_with_bad_pointer();
+ 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))); \
+ })
+
+#endif /* __KERNEL__ */
+
/*
* Memory barrier.
*