On 2020-05-28 03:06:55 [+0000], Lai Jiangshan wrote: > So that put_unbound_pool() can ensure all workers in idle, > no unfinished manager. And it doens't need to wait any manager > and can go to delete all the idle workers straight away. > > Also removes manager waitqueue, because it is unneeded and as > Sebastian Andrzej Siewior said: > > The workqueue code has it's internal spinlock (pool::lock) and also > implicit spinlock usage in the wq_manager waitqueue. These spinlocks > are converted to 'sleeping' spinlocks on a RT-kernel. > > Workqueue functions can be invoked from contexts which are truly atomic > even on a PREEMPT_RT enabled kernel. Taking sleeping locks from such > contexts is forbidden. > > pool::lock can be converted to a raw spinlock as the lock held times > are short. But the workqueue manager waitqueue is handled inside of > pool::lock held regions which again violates the lock nesting rules > of raw and regular spinlocks.
This seems to work for my test case I had test my chance. And lockdep didn't complain so… If you prefer this over my 1/2 what do we do about 2/2? Do you want me to repost it? Sebastian
