On Wed, Nov 18, 2009 at 22:33, Matthew Garrett <mjg59@xxxxxxxxxxxxx> wrote: > On Wed, Nov 18, 2009 at 10:06:33PM +0100, Kay Sievers wrote: > >> That's true, but I think there is a significant difference between >> polling every one or two seconds for media changes, and usually one or >> two minutes for a disk idle. It's not that we poll in a rather hight >> frequency, in an arbitrary interval, and check if some condition is >> met. > > My use cases are on the order of a second. > >> I still don't think that we should add new event interfaces which are >> single-subscriber only, and use global values for a specific user. >> What if there will be another independent user for this, which might >> want a different timeout? They fight over the trigger value to set in >> sysfs? > > You can trivially multiplex without any additional wakeups. Something > like devkit-disks can simply trigger on the lowest requested time and > then schedule wakeups for subscribers who want a different timeout. No, it can't do this race-free. And it's far from trivial. It can not know when something changes the single global value. Kay -- To unsubscribe from this list: send the line "unsubscribe linux-hotplug" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
