#ifndef _ASM_GENERIC_LOCAL_H
#define _ASM_GENERIC_LOCAL_H
-#include <linux/config.h>
#include <linux/percpu.h>
-#include <linux/hardirq.h>
+#include <asm/atomic.h>
#include <asm/types.h>
-/* An unsigned long type for operations which are atomic for a single
- * CPU. Usually used in combination with per-cpu variables. */
+/*
+ * A signed long type for operations which are atomic for a single CPU.
+ * Usually used in combination with per-cpu variables.
+ *
+ * This is the default implementation, which uses atomic_long_t. Which is
+ * rather pointless. The whole point behind local_t is that some processors
+ * can perform atomic adds and subtracts in a manner which is atomic wrt IRQs
+ * running on this CPU. local_t allows exploitation of such capabilities.
+ */
-#if BITS_PER_LONG == 32
/* Implement in terms of atomics. */
/* Don't use typedef: don't want them to be mixed with atomic_t's. */
typedef struct
{
- atomic_t a;
+ atomic_long_t a;
} local_t;
-#define LOCAL_INIT(i) { ATOMIC_INIT(i) }
+#define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) }
+
+#define local_read(l) atomic_long_read(&(l)->a)
+#define local_set(l,i) atomic_long_set((&(l)->a),(i))
+#define local_inc(l) atomic_long_inc(&(l)->a)
+#define local_dec(l) atomic_long_dec(&(l)->a)
+#define local_add(i,l) atomic_long_add((i),(&(l)->a))
+#define local_sub(i,l) atomic_long_sub((i),(&(l)->a))
-#define local_read(l) ((unsigned long)atomic_read(&(l)->a))
-#define local_set(l,i) atomic_set((&(l)->a),(i))
-#define local_inc(l) atomic_inc(&(l)->a)
-#define local_dec(l) atomic_dec(&(l)->a)
-#define local_add(i,l) atomic_add((i),(&(l)->a))
-#define local_sub(i,l) atomic_sub((i),(&(l)->a))
+#define local_sub_and_test(i, l) atomic_long_sub_and_test((i), (&(l)->a))
+#define local_dec_and_test(l) atomic_long_dec_and_test(&(l)->a)
+#define local_inc_and_test(l) atomic_long_inc_and_test(&(l)->a)
+#define local_add_negative(i, l) atomic_long_add_negative((i), (&(l)->a))
+#define local_add_return(i, l) atomic_long_add_return((i), (&(l)->a))
+#define local_sub_return(i, l) atomic_long_sub_return((i), (&(l)->a))
+#define local_inc_return(l) atomic_long_inc_return(&(l)->a)
+
+#define local_cmpxchg(l, o, n) atomic_long_cmpxchg((&(l)->a), (o), (n))
+#define local_xchg(l, n) atomic_long_xchg((&(l)->a), (n))
+#define local_add_unless(l, _a, u) atomic_long_add_unless((&(l)->a), (_a), (u))
+#define local_inc_not_zero(l) atomic_long_inc_not_zero(&(l)->a)
/* Non-atomic variants, ie. preemption disabled and won't be touched
* in interrupt, etc. Some archs can optimize this case well. */
#define __local_add(i,l) local_set((l), local_read(l) + (i))
#define __local_sub(i,l) local_set((l), local_read(l) - (i))
-#else /* ... can't use atomics. */
-/* Implement in terms of three variables.
- Another option would be to use local_irq_save/restore. */
-
-typedef struct
-{
- /* 0 = in hardirq, 1 = in softirq, 2 = usermode. */
- unsigned long v[3];
-} local_t;
-
-#define _LOCAL_VAR(l) ((l)->v[!in_interrupt() + !in_irq()])
-
-#define LOCAL_INIT(i) { { (i), 0, 0 } }
-
-static inline unsigned long local_read(local_t *l)
-{
- return l->v[0] + l->v[1] + l->v[2];
-}
-
-static inline void local_set(local_t *l, unsigned long v)
-{
- l->v[0] = v;
- l->v[1] = l->v[2] = 0;
-}
-
-static inline void local_inc(local_t *l)
-{
- preempt_disable();
- _LOCAL_VAR(l)++;
- preempt_enable();
-}
-
-static inline void local_dec(local_t *l)
-{
- preempt_disable();
- _LOCAL_VAR(l)--;
- preempt_enable();
-}
-
-static inline void local_add(unsigned long v, local_t *l)
-{
- preempt_disable();
- _LOCAL_VAR(l) += v;
- preempt_enable();
-}
-
-static inline void local_sub(unsigned long v, local_t *l)
-{
- preempt_disable();
- _LOCAL_VAR(l) -= v;
- preempt_enable();
-}
-
-/* Non-atomic variants, ie. preemption disabled and won't be touched
- * in interrupt, etc. Some archs can optimize this case well. */
-#define __local_inc(l) ((l)->v[0]++)
-#define __local_dec(l) ((l)->v[0]--)
-#define __local_add(i,l) ((l)->v[0] += (i))
-#define __local_sub(i,l) ((l)->v[0] -= (i))
-
-#endif /* Non-atomic implementation */
-
/* Use these for per-cpu local_t variables: on some archs they are
* much more efficient than these naive implementations. Note they take
* a variable (eg. mystruct.foo), not an address.
*/
-#define cpu_local_read(v) local_read(&__get_cpu_var(v))
-#define cpu_local_set(v, i) local_set(&__get_cpu_var(v), (i))
-#define cpu_local_inc(v) local_inc(&__get_cpu_var(v))
-#define cpu_local_dec(v) local_dec(&__get_cpu_var(v))
-#define cpu_local_add(i, v) local_add((i), &__get_cpu_var(v))
-#define cpu_local_sub(i, v) local_sub((i), &__get_cpu_var(v))
+#define cpu_local_read(l) local_read(&__get_cpu_var(l))
+#define cpu_local_set(l, i) local_set(&__get_cpu_var(l), (i))
+#define cpu_local_inc(l) local_inc(&__get_cpu_var(l))
+#define cpu_local_dec(l) local_dec(&__get_cpu_var(l))
+#define cpu_local_add(i, l) local_add((i), &__get_cpu_var(l))
+#define cpu_local_sub(i, l) local_sub((i), &__get_cpu_var(l))
/* Non-atomic increments, ie. preemption disabled and won't be touched
* in interrupt, etc. Some archs can optimize this case well.
*/
-#define __cpu_local_inc(v) __local_inc(&__get_cpu_var(v))
-#define __cpu_local_dec(v) __local_dec(&__get_cpu_var(v))
-#define __cpu_local_add(i, v) __local_add((i), &__get_cpu_var(v))
-#define __cpu_local_sub(i, v) __local_sub((i), &__get_cpu_var(v))
+#define __cpu_local_inc(l) __local_inc(&__get_cpu_var(l))
+#define __cpu_local_dec(l) __local_dec(&__get_cpu_var(l))
+#define __cpu_local_add(i, l) __local_add((i), &__get_cpu_var(l))
+#define __cpu_local_sub(i, l) __local_sub((i), &__get_cpu_var(l))
#endif /* _ASM_GENERIC_LOCAL_H */
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