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Diffstat (limited to 'arch/arm/include/asm/atomic.h')
-rw-r--r--arch/arm/include/asm/atomic.h49
1 files changed, 40 insertions, 9 deletions
diff --git a/arch/arm/include/asm/atomic.h b/arch/arm/include/asm/atomic.h
index 62d2cb53b069..3040359094d9 100644
--- a/arch/arm/include/asm/atomic.h
+++ b/arch/arm/include/asm/atomic.h
@@ -60,6 +60,7 @@ static inline int atomic_add_return(int i, atomic_t *v)
int result;
smp_mb();
+ prefetchw(&v->counter);
__asm__ __volatile__("@ atomic_add_return\n"
"1: ldrex %0, [%3]\n"
@@ -99,6 +100,7 @@ static inline int atomic_sub_return(int i, atomic_t *v)
int result;
smp_mb();
+ prefetchw(&v->counter);
__asm__ __volatile__("@ atomic_sub_return\n"
"1: ldrex %0, [%3]\n"
@@ -121,6 +123,7 @@ static inline int atomic_cmpxchg(atomic_t *ptr, int old, int new)
unsigned long res;
smp_mb();
+ prefetchw(&ptr->counter);
do {
__asm__ __volatile__("@ atomic_cmpxchg\n"
@@ -138,6 +141,33 @@ static inline int atomic_cmpxchg(atomic_t *ptr, int old, int new)
return oldval;
}
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
+{
+ int oldval, newval;
+ unsigned long tmp;
+
+ smp_mb();
+ prefetchw(&v->counter);
+
+ __asm__ __volatile__ ("@ atomic_add_unless\n"
+"1: ldrex %0, [%4]\n"
+" teq %0, %5\n"
+" beq 2f\n"
+" add %1, %0, %6\n"
+" strex %2, %1, [%4]\n"
+" teq %2, #0\n"
+" bne 1b\n"
+"2:"
+ : "=&r" (oldval), "=&r" (newval), "=&r" (tmp), "+Qo" (v->counter)
+ : "r" (&v->counter), "r" (u), "r" (a)
+ : "cc");
+
+ if (oldval != u)
+ smp_mb();
+
+ return oldval;
+}
+
#else /* ARM_ARCH_6 */
#ifdef CONFIG_SMP
@@ -186,10 +216,6 @@ static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
return ret;
}
-#endif /* __LINUX_ARM_ARCH__ */
-
-#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
-
static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
@@ -200,6 +226,10 @@ static inline int __atomic_add_unless(atomic_t *v, int a, int u)
return c;
}
+#endif /* __LINUX_ARM_ARCH__ */
+
+#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+
#define atomic_inc(v) atomic_add(1, v)
#define atomic_dec(v) atomic_sub(1, v)
@@ -211,11 +241,6 @@ static inline int __atomic_add_unless(atomic_t *v, int a, int u)
#define atomic_add_negative(i,v) (atomic_add_return(i, v) < 0)
-#define smp_mb__before_atomic_dec() smp_mb()
-#define smp_mb__after_atomic_dec() smp_mb()
-#define smp_mb__before_atomic_inc() smp_mb()
-#define smp_mb__after_atomic_inc() smp_mb()
-
#ifndef CONFIG_GENERIC_ATOMIC64
typedef struct {
long long counter;
@@ -299,6 +324,7 @@ static inline long long atomic64_add_return(long long i, atomic64_t *v)
unsigned long tmp;
smp_mb();
+ prefetchw(&v->counter);
__asm__ __volatile__("@ atomic64_add_return\n"
"1: ldrexd %0, %H0, [%3]\n"
@@ -340,6 +366,7 @@ static inline long long atomic64_sub_return(long long i, atomic64_t *v)
unsigned long tmp;
smp_mb();
+ prefetchw(&v->counter);
__asm__ __volatile__("@ atomic64_sub_return\n"
"1: ldrexd %0, %H0, [%3]\n"
@@ -364,6 +391,7 @@ static inline long long atomic64_cmpxchg(atomic64_t *ptr, long long old,
unsigned long res;
smp_mb();
+ prefetchw(&ptr->counter);
do {
__asm__ __volatile__("@ atomic64_cmpxchg\n"
@@ -388,6 +416,7 @@ static inline long long atomic64_xchg(atomic64_t *ptr, long long new)
unsigned long tmp;
smp_mb();
+ prefetchw(&ptr->counter);
__asm__ __volatile__("@ atomic64_xchg\n"
"1: ldrexd %0, %H0, [%3]\n"
@@ -409,6 +438,7 @@ static inline long long atomic64_dec_if_positive(atomic64_t *v)
unsigned long tmp;
smp_mb();
+ prefetchw(&v->counter);
__asm__ __volatile__("@ atomic64_dec_if_positive\n"
"1: ldrexd %0, %H0, [%3]\n"
@@ -436,6 +466,7 @@ static inline int atomic64_add_unless(atomic64_t *v, long long a, long long u)
int ret = 1;
smp_mb();
+ prefetchw(&v->counter);
__asm__ __volatile__("@ atomic64_add_unless\n"
"1: ldrexd %0, %H0, [%4]\n"