Re: gpiolib gpio_chrdev_release duration is about 30 ms

[Maxim Kochetkov <fido_max@xxxxxxxx>]

I need a small userspace program to do some GPIO magic to communicate 
other hardware like devmem. This program takes about 2,5 seconds just to 
find GPIO lines by name.

replacing synchronize_rcu to synchronize_rcu_expedited in 
atomic_notifier_chain_unregister gives the same boost as removing 
synchronize_rcu

17.07.2020 16:37, Linus Walleij пишет:
> Are you just testing because
> curious or do you need to meet a design objective?