On Tue, Apr 16, 2019 at 06:01:13PM +0200, Peter Zijlstra wrote:
> @@ -794,34 +770,38 @@ static inline int __down_read_trylock(st
> */
> static inline void __down_write(struct rw_semaphore *sem)
> {
> - if (unlikely(atomic_long_cmpxchg_acquire(&sem->count, 0,
> - RWSEM_WRITER_LOCKED)))
> - rwsem_down_write_failed(sem);
> + long tmp = RWSEM_UNLOCKED_VALUE;
> +
> + if (unlikely(atomic_long_try_cmpxchg_acquire(&sem->count, &tmp,
> + RWSEM_WRITER_LOCKED)))
!
> + rwsem_down_write_slow(sem, TASK_UNINTERRUPTIBLE);
> rwsem_set_owner(sem);
> }
>
> static inline int __down_write_killable(struct rw_semaphore *sem)
> {
> - if (unlikely(atomic_long_cmpxchg_acquire(&sem->count, 0,
> - RWSEM_WRITER_LOCKED)))
> - if (IS_ERR(rwsem_down_write_failed_killable(sem)))
> + long tmp = RWSEM_UNLOCKED_VALUE;
> +
> + if (unlikely(atomic_long_try_cmpxchg_acquire(&sem->count, &tmp,
> + RWSEM_WRITER_LOCKED))) {
also !
> + if (IS_ERR(rwsem_down_write_slow(sem, TASK_KILLABLE)))
> return -EINTR;
> + }
> rwsem_set_owner(sem);
> return 0;
> }
I'm having a great day it seems, it's like back in uni, trying to find
all the missing - signs in this page-long DE.
