Oleg Nesterov <[email protected]> writes: > On 09/17, Rafael J. Wysocki wrote: >> >> On Fri, Sep 14, 2018 at 6:21 PM Oleg Nesterov <[email protected]> wrote: >> > >> > > > Since you are adding the notifier anyway, what about designing it to >> > > > make >> > > > the thread wait on _PREPARE until the notifier kicks it again on exit >> > > > fron suspend/hibernation? >> > >> > Well. I agree that freezable kthreads are not nice, but it seems you are >> > going to add another questionable interface ;) >> >> Why would it be questionable? >> >> The watchdog needs to be disarmed somehow before tasks are frozen and >> re-armed after they have been thawed or it may report false-positives >> on the way out. PM notifiers can be used for that. > > Or watchdog() can simply use set_freezable/freezing interface we already > have, without additional complications. > > Yes, this is not "before tasks are frozen", but probably should work? > > OK, I won't argue.
I was hoping you and Rafael will come to an agreement but the discussion just died ... so where do we stand on this? I see the following options: 1) The v1 patch is good, no freezing/disabling/parking required. 2) Make the kthread freezable (btw, I tested your patch and it seems to work). 3) kthread_stop/kthread_run() (as you said 'no parking'). 4) Drop the patch and wait for the root cause (increasing jiffies) to dissolve. 5) ??? Ideas? -- Vitaly
