[$] Juggling software interrupts and realtime tasks

The software-interrupt mechanism is one of the oldest parts in the kernel;arguably, the basic design behind it predates Linux itself. Softwareinterrupts can get in the way of other work so, for almost aslong as they have existed, developers have wished that theycould be made to go away. That has never happened, though, and doesn'tlook imminent. Instead, Android systems have long carried a patch thattries to minimize the impact of software interrupts, at least in somesituations. John Stultz is now postingthat work, which contains contributions from a number of authors, inthe hope of getting it into the mainline kernel.