On Wed 11-05-16 10:44:01, Peter Zijlstra wrote: [...] > @@ -504,6 +502,18 @@ __rwsem_down_write_failed_common(struct rw_semaphore > *sem, int state) > raw_spin_unlock_irq(&sem->wait_lock); > > return ret; > + > +out_nolock: > + __set_current_state(TASK_RUNNING); > + raw_spin_lock_irq(&sem->wait_lock); > + list_del(&waiter.list); > + if (list_empty(&sem->wait_list)) > + rwsem_atomic_update(-RWSEM_WAITING_BIAS, sem); > + else > + __rwsem_do_wake(sem, RWSEM_WAKE_READERS); > + raw_spin_unlock_irq(&sem->wait_lock); > + > + return ERR_PTR(-EINTR); > }
Looks much better but don't we have to check the count for potentially pending writers? -- Michal Hocko SUSE Labs
