On Fri, Oct 31, 2014 at 10:38:02PM +0100, Oleg Nesterov wrote: > On 10/31, Peter Zijlstra wrote: > > > > Provide better implementations of wait_event_freezable() APIs. > > > > The problem is with freezer_do_not_count(), it hides the thread from > > the freezer, even though this thread might not actually freeze/sleep > > at all. > > I agree, wait_event_freezable() is awful. But could you clarify "at all" ? > > Sure, the task can be preempted right after it sets, it can do a lot > of things before it calls schedule(), it can be woken after that and > it can run again and do something else before freezer_count() calls > try_to_freeze(), etc. > > Is this what you meant?
Yes. > > +#define __wait_event_freezable(wq, condition) > > \ > > + (void)___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ > > + schedule(); try_to_freeze()) > > I don't think this can work. Yeah, that was horribly broken. defconfig didn't seem to find a usage site. Wu's robot offered a .config quickly enough though ;-) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
