> > > It's been some time since I have looked into this code so bear with me. > > > One thing is not really clear to me. Why does it help to exclude this > > > particular task from the freezer > > > > we don't exclude it, > > > > > when it is not sleeping in the freezer. > > > > Yes, it is not sleeping in __refrigerator(), but it does > > > > schedule(); > > freezer_count(); > > > > so it will enter __refrigerator() right after wakeup. If it won't be > woken > > up we do not care, we can consider it "frozen". > > Right, but this is just silencing the freezing code to exclude this > task, right? > > > > I can see how other threads need to be zapped and TASK_WAKEKILL > doesn't > > > do that but shouldn't we fix that instead? > > > > Not sure I understand, but unlikely we can (or want) to make > __refrigerator() > > killable. > > Why would that be a problem. If the kill is fatal then why to keep the > killed task in the fridge? > Is it different between 'the killed task is frozen' and '__refrigerator() is killable'? >From a general '__refrigerator()' implementation point of view I know that it should not be killable. > > Otherwise, how can we fix that? > > We can mark all threads PF_NOFREEZE and wake them up. This would require > some more changes of course but wouldn't that be a more appropriate > solution? Do we want to block exec for ever just because some threads > are in the fridge? > IMHO, It seems to be difficult and buggy to control with PF_NOFREEZE. Because, The sub-thread can freeze and receive SIG_KILL before the marking of PF_NOFREEZE and it should be freezable in other cases. I don't understand why it isn't appropriate for exec to block. The exec can freeze. When tasks are thawed, the killed sub-thread will die and wake de_thread(). The exec will continue to work from resume. Chanho
