On Wednesday, November 16, 2016 4:20:47 PM CET Linus Walleij wrote:

On Wed, Nov 16, 2016 at 1:46 PM, Rafael J. Wysocki [off-list ref] wrote:

quoted

Well, we had a session at the KS regarding usage of the freezer on
kernel threads and the conclusion was to get rid of that (as opposed
to freezing user space, which is necessary IMO).  So this change would
go in the opposite direction. 

Aha so I should not make this thread look like everyone else, instead
everyone else should look like this thread, haha 

Ah well, I'll just drop it.

It would still be good to remove the semaphore and do something else,
as we also want to remove all semaphores. ;-)

We could check "mq->flags & MMC_QUEUE_SUSPENDED" in the kthread to see
if the queue is currently suspended, and otherwise go to sleep there,
and then call wake_up() in the resume function.

While looking at that code, I just noticed that access to 
mq->flags is racy and should be fixed as well.

	Arnd