0001-ARM64-add-support-for-atomic-operations.patch

From 6e0a3975a66fb14d7b5d029d3e460dc5410f1621 Mon Sep 17 00:00:00 2001
From: Adam Oleksy <adam.oleksy@nokia.com>
Date: Tue, 6 Sep 2016 11:53:09 +0200
Subject: [PATCH] ARM64: add support for atomic operations

---
 arch/arm/include/asm/atomic.h | 43 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)

diff --git a/arch/arm/include/asm/atomic.h b/arch/arm/include/asm/atomic.h
index 9b79506..bc9f717 100644
--- a/arch/arm/include/asm/atomic.h
+++ b/arch/arm/include/asm/atomic.h
@@ -29,6 +29,8 @@ typedef struct { volatile int counter; } atomic_t;

 #define atomic_read(v)	((v)->counter)
 #define atomic_set(v,i)	(((v)->counter) = (i))
+#define atomic64_read(v)	atomic_read(v)
+#define atomic64_set(v,i)	atomic_set(v,i)

 static inline void atomic_add(int i, volatile atomic_t *v)
 {
@@ -101,6 +103,47 @@ static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
 	local_irq_restore(flags);
 }

+#if BITS_PER_LONG == 32
+typedef struct { volatile long long counter; } atomic64_t;
+static inline void atomic64_sub(long long i, volatile atomic64_t *v)
+{
+	unsigned long flags = 0;
+
+	local_irq_save(flags);
+	v->counter -= i;
+	local_irq_restore(flags);
+}
+#else /* BIT_PER_LONG == 32 */
+typedef struct { volatile long counter; } atomic64_t;
+
+static inline void atomic64_sub(long i, volatile atomic64_t *v)
+{
+	unsigned long flags = 0;
+
+	local_irq_save(flags);
+	v->counter -= i;
+	local_irq_restore(flags);
+}
+#endif
+
+static inline void atomic64_inc(volatile atomic64_t *v)
+{
+	unsigned long flags = 0;
+
+	local_irq_save(flags);
+	v->counter += 1;
+	local_irq_restore(flags);
+}
+
+static inline void atomic64_dec(volatile atomic64_t *v)
+{
+	unsigned long flags = 0;
+
+	local_irq_save(flags);
+	v->counter -= 1;
+	local_irq_restore(flags);
+}
+
 /* Atomic operations are already serializing on ARM */
 #define smp_mb__before_atomic_dec()	barrier()
 #define smp_mb__after_atomic_dec()	barrier()
--
2.6.2