locking,arch: Rewrite generic atomic support
Rewrite generic atomic support to only require cmpxchg(), generate all
other primitives from that.
Furthermore reduce the endless repetition for all these primitives to
a few CPP macros. This way we get more for less lines.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140508135852.940119622@infradead.org
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/lib/atomic64.c b/lib/atomic64.c
index 08a4f06..1298c05e 100644
--- a/lib/atomic64.c
+++ b/lib/atomic64.c
@@ -70,53 +70,42 @@
}
EXPORT_SYMBOL(atomic64_set);
-void atomic64_add(long long a, atomic64_t *v)
-{
- unsigned long flags;
- raw_spinlock_t *lock = lock_addr(v);
+#define ATOMIC64_OP(op, c_op) \
+void atomic64_##op(long long a, atomic64_t *v) \
+{ \
+ unsigned long flags; \
+ raw_spinlock_t *lock = lock_addr(v); \
+ \
+ raw_spin_lock_irqsave(lock, flags); \
+ v->counter c_op a; \
+ raw_spin_unlock_irqrestore(lock, flags); \
+} \
+EXPORT_SYMBOL(atomic64_##op);
- raw_spin_lock_irqsave(lock, flags);
- v->counter += a;
- raw_spin_unlock_irqrestore(lock, flags);
-}
-EXPORT_SYMBOL(atomic64_add);
+#define ATOMIC64_OP_RETURN(op, c_op) \
+long long atomic64_##op##_return(long long a, atomic64_t *v) \
+{ \
+ unsigned long flags; \
+ raw_spinlock_t *lock = lock_addr(v); \
+ long long val; \
+ \
+ raw_spin_lock_irqsave(lock, flags); \
+ val = (v->counter c_op a); \
+ raw_spin_unlock_irqrestore(lock, flags); \
+ return val; \
+} \
+EXPORT_SYMBOL(atomic64_##op##_return);
-long long atomic64_add_return(long long a, atomic64_t *v)
-{
- unsigned long flags;
- raw_spinlock_t *lock = lock_addr(v);
- long long val;
+#define ATOMIC64_OPS(op, c_op) \
+ ATOMIC64_OP(op, c_op) \
+ ATOMIC64_OP_RETURN(op, c_op)
- raw_spin_lock_irqsave(lock, flags);
- val = v->counter += a;
- raw_spin_unlock_irqrestore(lock, flags);
- return val;
-}
-EXPORT_SYMBOL(atomic64_add_return);
+ATOMIC64_OPS(add, +=)
+ATOMIC64_OPS(sub, -=)
-void atomic64_sub(long long a, atomic64_t *v)
-{
- unsigned long flags;
- raw_spinlock_t *lock = lock_addr(v);
-
- raw_spin_lock_irqsave(lock, flags);
- v->counter -= a;
- raw_spin_unlock_irqrestore(lock, flags);
-}
-EXPORT_SYMBOL(atomic64_sub);
-
-long long atomic64_sub_return(long long a, atomic64_t *v)
-{
- unsigned long flags;
- raw_spinlock_t *lock = lock_addr(v);
- long long val;
-
- raw_spin_lock_irqsave(lock, flags);
- val = v->counter -= a;
- raw_spin_unlock_irqrestore(lock, flags);
- return val;
-}
-EXPORT_SYMBOL(atomic64_sub_return);
+#undef ATOMIC64_OPS
+#undef ATOMIC64_OP_RETURN
+#undef ATOMIC64_OP
long long atomic64_dec_if_positive(atomic64_t *v)
{