[PATCH 1/1] lib:atomic64 using raw_spin_lock_irq[save|resotre] for atomicity

[Shan Hai]

The spin_lock_irq[save|restore] could break the atomicity of the
atomic64_* operations in the PREEMPT-RT configuration, because
the spin_lock_irq[save|restore] themselves are preemptable in the
PREEMPT-RT, using raw variant of the spin lock could provide the
atomicity that atomic64_* need.

Signed-off-by: Shan Hai <haishan.bai@xxxxxxxxx>
---
 lib/atomic64.c |   40 ++++++++++++++++++++--------------------
 1 files changed, 20 insertions(+), 20 deletions(-)

diff --git a/lib/atomic64.c b/lib/atomic64.c
index e12ae0d..26f524a 100644
--- a/lib/atomic64.c
+++ b/lib/atomic64.c
@@ -48,9 +48,9 @@ long long atomic64_read(const atomic64_t *v)
 	spinlock_t *lock = lock_addr(v);
 	long long val;
 
-	spin_lock_irqsave(lock, flags);
+	raw_spin_lock_irqsave(lock, flags);
 	val = v->counter;
-	spin_unlock_irqrestore(lock, flags);
+	raw_spin_unlock_irqrestore(lock, flags);
 	return val;
 }
 EXPORT_SYMBOL(atomic64_read);
@@ -60,9 +60,9 @@ void atomic64_set(atomic64_t *v, long long i)
 	unsigned long flags;
 	spinlock_t *lock = lock_addr(v);
 
-	spin_lock_irqsave(lock, flags);
+	raw_spin_lock_irqsave(lock, flags);
 	v->counter = i;
-	spin_unlock_irqrestore(lock, flags);
+	raw_spin_unlock_irqrestore(lock, flags);
 }
 EXPORT_SYMBOL(atomic64_set);
 
@@ -71,9 +71,9 @@ void atomic64_add(long long a, atomic64_t *v)
 	unsigned long flags;
 	spinlock_t *lock = lock_addr(v);
 
-	spin_lock_irqsave(lock, flags);
+	raw_spin_lock_irqsave(lock, flags);
 	v->counter += a;
-	spin_unlock_irqrestore(lock, flags);
+	raw_spin_unlock_irqrestore(lock, flags);
 }
 EXPORT_SYMBOL(atomic64_add);
 
@@ -83,9 +83,9 @@ long long atomic64_add_return(long long a, atomic64_t *v)
 	spinlock_t *lock = lock_addr(v);
 	long long val;
 
-	spin_lock_irqsave(lock, flags);
+	raw_spin_lock_irqsave(lock, flags);
 	val = v->counter += a;
-	spin_unlock_irqrestore(lock, flags);
+	raw_spin_unlock_irqrestore(lock, flags);
 	return val;
 }
 EXPORT_SYMBOL(atomic64_add_return);
@@ -95,9 +95,9 @@ void atomic64_sub(long long a, atomic64_t *v)
 	unsigned long flags;
 	spinlock_t *lock = lock_addr(v);
 
-	spin_lock_irqsave(lock, flags);
+	raw_spin_lock_irqsave(lock, flags);
 	v->counter -= a;
-	spin_unlock_irqrestore(lock, flags);
+	raw_spin_unlock_irqrestore(lock, flags);
 }
 EXPORT_SYMBOL(atomic64_sub);
 
@@ -107,9 +107,9 @@ long long atomic64_sub_return(long long a, atomic64_t *v)
 	spinlock_t *lock = lock_addr(v);
 	long long val;
 
-	spin_lock_irqsave(lock, flags);
+	raw_spin_lock_irqsave(lock, flags);
 	val = v->counter -= a;
-	spin_unlock_irqrestore(lock, flags);
+	raw_spin_unlock_irqrestore(lock, flags);
 	return val;
 }
 EXPORT_SYMBOL(atomic64_sub_return);
@@ -120,11 +120,11 @@ long long atomic64_dec_if_positive(atomic64_t *v)
 	spinlock_t *lock = lock_addr(v);
 	long long val;
 
-	spin_lock_irqsave(lock, flags);
+	raw_spin_lock_irqsave(lock, flags);
 	val = v->counter - 1;
 	if (val >= 0)
 		v->counter = val;
-	spin_unlock_irqrestore(lock, flags);
+	raw_spin_unlock_irqrestore(lock, flags);
 	return val;
 }
 EXPORT_SYMBOL(atomic64_dec_if_positive);
@@ -135,11 +135,11 @@ long long atomic64_cmpxchg(atomic64_t *v, long long o, long long n)
 	spinlock_t *lock = lock_addr(v);
 	long long val;
 
-	spin_lock_irqsave(lock, flags);
+	raw_spin_lock_irqsave(lock, flags);
 	val = v->counter;
 	if (val == o)
 		v->counter = n;
-	spin_unlock_irqrestore(lock, flags);
+	raw_spin_unlock_irqrestore(lock, flags);
 	return val;
 }
 EXPORT_SYMBOL(atomic64_cmpxchg);
@@ -150,10 +150,10 @@ long long atomic64_xchg(atomic64_t *v, long long new)
 	spinlock_t *lock = lock_addr(v);
 	long long val;
 
-	spin_lock_irqsave(lock, flags);
+	raw_spin_lock_irqsave(lock, flags);
 	val = v->counter;
 	v->counter = new;
-	spin_unlock_irqrestore(lock, flags);
+	raw_spin_unlock_irqrestore(lock, flags);
 	return val;
 }
 EXPORT_SYMBOL(atomic64_xchg);
@@ -164,12 +164,12 @@ int atomic64_add_unless(atomic64_t *v, long long a, long long u)
 	spinlock_t *lock = lock_addr(v);
 	int ret = 0;
 
-	spin_lock_irqsave(lock, flags);
+	raw_spin_lock_irqsave(lock, flags);
 	if (v->counter != u) {
 		v->counter += a;
 		ret = 1;
 	}
-	spin_unlock_irqrestore(lock, flags);
+	raw_spin_unlock_irqrestore(lock, flags);
 	return ret;
 }
 EXPORT_SYMBOL(atomic64_add_unless);
-- 
1.7.4.1

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