diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2014-04-23 16:12:30 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2014-08-14 12:48:14 +0200 |
| commit | 560cb12a4080a48b84da8b96878cafbd193c4d64 (patch) | |
| tree | e0b28be89d66e8a01b164b7c6123e918cafcc79c /lib/atomic64.c | |
| parent | d4608dd5b4ec13855680b89f719d8d4b2da92411 (diff) | |
| download | lwn-560cb12a4080a48b84da8b96878cafbd193c4d64.tar.gz lwn-560cb12a4080a48b84da8b96878cafbd193c4d64.zip | |
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>
Diffstat (limited to 'lib/atomic64.c')
| -rw-r--r-- | lib/atomic64.c | 83 |
1 files changed, 36 insertions, 47 deletions
diff --git a/lib/atomic64.c b/lib/atomic64.c index 08a4f068e61e..1298c05ef528 100644 --- a/lib/atomic64.c +++ b/lib/atomic64.c @@ -70,53 +70,42 @@ void atomic64_set(atomic64_t *v, long long i) } EXPORT_SYMBOL(atomic64_set); -void atomic64_add(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_add); - -long long atomic64_add_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_add_return); - -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); +#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); + +#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); + +#define ATOMIC64_OPS(op, c_op) \ + ATOMIC64_OP(op, c_op) \ + ATOMIC64_OP_RETURN(op, c_op) + +ATOMIC64_OPS(add, +=) +ATOMIC64_OPS(sub, -=) + +#undef ATOMIC64_OPS +#undef ATOMIC64_OP_RETURN +#undef ATOMIC64_OP long long atomic64_dec_if_positive(atomic64_t *v) { |