#ifndef __ASM_ARM_ATOMIC_H
#define __ASM_ARM_ATOMIC_H
-#include <linux/config.h>
+#include <linux/compiler.h>
typedef struct { volatile int counter; } atomic_t;
: "cc");
}
-static inline void atomic_add(int i, atomic_t *v)
+static inline int atomic_add_return(int i, atomic_t *v)
{
- unsigned long tmp, tmp2;
+ unsigned long tmp;
+ int result;
- __asm__ __volatile__("@ atomic_add\n"
+ __asm__ __volatile__("@ atomic_add_return\n"
"1: ldrex %0, [%2]\n"
" add %0, %0, %3\n"
" strex %1, %0, [%2]\n"
" teq %1, #0\n"
" bne 1b"
- : "=&r" (tmp), "=&r" (tmp2)
+ : "=&r" (result), "=&r" (tmp)
: "r" (&v->counter), "Ir" (i)
: "cc");
-}
-static inline void atomic_sub(int i, atomic_t *v)
-{
- unsigned long tmp, tmp2;
-
- __asm__ __volatile__("@ atomic_sub\n"
-"1: ldrex %0, [%2]\n"
-" sub %0, %0, %3\n"
-" strex %1, %0, [%2]\n"
-" teq %1, #0\n"
-" bne 1b"
- : "=&r" (tmp), "=&r" (tmp2)
- : "r" (&v->counter), "Ir" (i)
- : "cc");
+ return result;
}
-#define atomic_inc(v) atomic_add(1, v)
-#define atomic_dec(v) atomic_sub(1, v)
-
-static inline int atomic_dec_and_test(atomic_t *v)
+static inline int atomic_sub_return(int i, atomic_t *v)
{
unsigned long tmp;
int result;
- __asm__ __volatile__("@ atomic_dec_and_test\n"
+ __asm__ __volatile__("@ atomic_sub_return\n"
"1: ldrex %0, [%2]\n"
-" sub %0, %0, #1\n"
+" sub %0, %0, %3\n"
" strex %1, %0, [%2]\n"
" teq %1, #0\n"
" bne 1b"
: "=&r" (result), "=&r" (tmp)
- : "r" (&v->counter)
+ : "r" (&v->counter), "Ir" (i)
: "cc");
- return result == 0;
+ return result;
}
-static inline int atomic_add_negative(int i, atomic_t *v)
+static inline int atomic_cmpxchg(atomic_t *ptr, int old, int new)
{
- unsigned long tmp;
- int result;
-
- __asm__ __volatile__("@ atomic_add_negative\n"
-"1: ldrex %0, [%2]\n"
-" add %0, %0, %3\n"
-" strex %1, %0, [%2]\n"
-" teq %1, #0\n"
-" bne 1b"
- : "=&r" (result), "=&r" (tmp)
- : "r" (&v->counter), "Ir" (i)
- : "cc");
-
- return result < 0;
+ unsigned long oldval, res;
+
+ do {
+ __asm__ __volatile__("@ atomic_cmpxchg\n"
+ "ldrex %1, [%2]\n"
+ "mov %0, #0\n"
+ "teq %1, %3\n"
+ "strexeq %0, %4, [%2]\n"
+ : "=&r" (res), "=&r" (oldval)
+ : "r" (&ptr->counter), "Ir" (old), "r" (new)
+ : "cc");
+ } while (res);
+
+ return oldval;
}
static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
#define atomic_set(v,i) (((v)->counter) = (i))
-static inline void atomic_add(int i, atomic_t *v)
-{
- unsigned long flags;
-
- local_irq_save(flags);
- v->counter += i;
- local_irq_restore(flags);
-}
-
-static inline void atomic_sub(int i, atomic_t *v)
+static inline int atomic_add_return(int i, atomic_t *v)
{
unsigned long flags;
+ int val;
- local_irq_save(flags);
- v->counter -= i;
- local_irq_restore(flags);
-}
-
-static inline void atomic_inc(atomic_t *v)
-{
- unsigned long flags;
-
- local_irq_save(flags);
- v->counter += 1;
- local_irq_restore(flags);
-}
-
-static inline void atomic_dec(atomic_t *v)
-{
- unsigned long flags;
+ raw_local_irq_save(flags);
+ val = v->counter;
+ v->counter = val += i;
+ raw_local_irq_restore(flags);
- local_irq_save(flags);
- v->counter -= 1;
- local_irq_restore(flags);
+ return val;
}
-static inline int atomic_dec_and_test(atomic_t *v)
+static inline int atomic_sub_return(int i, atomic_t *v)
{
unsigned long flags;
int val;
- local_irq_save(flags);
+ raw_local_irq_save(flags);
val = v->counter;
- v->counter = val -= 1;
- local_irq_restore(flags);
+ v->counter = val -= i;
+ raw_local_irq_restore(flags);
- return val == 0;
+ return val;
}
-static inline int atomic_add_negative(int i, atomic_t *v)
+static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
{
+ int ret;
unsigned long flags;
- int val;
- local_irq_save(flags);
- val = v->counter;
- v->counter = val += i;
- local_irq_restore(flags);
+ raw_local_irq_save(flags);
+ ret = v->counter;
+ if (likely(ret == old))
+ v->counter = new;
+ raw_local_irq_restore(flags);
- return val < 0;
+ return ret;
}
static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
{
unsigned long flags;
- local_irq_save(flags);
+ raw_local_irq_save(flags);
*addr &= ~mask;
- local_irq_restore(flags);
+ raw_local_irq_restore(flags);
}
#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;
+
+ c = atomic_read(v);
+ while (c != u && (old = atomic_cmpxchg((v), c, c + a)) != c)
+ c = old;
+ return c != u;
+}
+#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+
+#define atomic_add(i, v) (void) atomic_add_return(i, v)
+#define atomic_inc(v) (void) atomic_add_return(1, v)
+#define atomic_sub(i, v) (void) atomic_sub_return(i, v)
+#define atomic_dec(v) (void) atomic_sub_return(1, v)
+
+#define atomic_inc_and_test(v) (atomic_add_return(1, v) == 0)
+#define atomic_dec_and_test(v) (atomic_sub_return(1, v) == 0)
+#define atomic_inc_return(v) (atomic_add_return(1, v))
+#define atomic_dec_return(v) (atomic_sub_return(1, v))
+#define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0)
+
+#define atomic_add_negative(i,v) (atomic_add_return(i, v) < 0)
+
/* Atomic operations are already serializing on ARM */
#define smp_mb__before_atomic_dec() barrier()
#define smp_mb__after_atomic_dec() barrier()
#define smp_mb__before_atomic_inc() barrier()
#define smp_mb__after_atomic_inc() barrier()
+#include <asm-generic/atomic.h>
#endif
#endif
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