On 01/17, Preeti U Murthy wrote: > > On 01/16/2013 05:32 PM, Ivo Sieben wrote: > > > > I don't have a problem that there is a context switch to the high > > priority process: it has a higher priority, so it probably is more > > important. > > My problem is that even when the waitqueue is empty, the high priority > > thread has a risk to block on the spinlock needlessly (causing context > > switches to low priority task and back to the high priority task) > > > Fair enough Ivo.I think you should go ahead with merging the > waitqueue_active() > wake_up() > logic into the wake_up() variants. This is not easy. We can't simply change wake_up*() helpers or modify __wake_up(). I can't understand why do you dislike Ivo's simple patch. There are a lot of "if (waitqueue_active) wake_up" examples. Even if we add the new helpers (personally I don't think this makes sense) , we can do this later. Why should we delay this fix? Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
