Messages in this thread Patch in this message | | | From | Shan Hai <> | Subject | [PATCH 1/1] lib:atomic64 using raw_spin_lock_irq[save|resotre] for atomicity | Date | Thu, 1 Sep 2011 09:28:00 +0800 |
| |
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@gmail.com> --- 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
| |