The realtime preemption mini-summit

“There is one part of the threaded interrupt code which remains
outside of the mainline: the piece which forces all drivers to use
threaded handlers. There are no plans to move that code into the
mainline; instead, it’s going to be a matter of persuasion to get
driver writers to switch to the newer way of doing things.

“Uptake in the mainline is small so far; few drivers are
actually using this feature. That is beginning to change, though;
the SCSI layer is one example. SCSI has always featured relatively
heavyweight interrupt-handling code and work done in
single-threaded workqueues. This code could move fairly naturally
to process context; the SCSI developers are said to be evaluating a
possible move toward threaded interrupt handlers in the near
future. There have also been suggestions that the network stack
might eventually move in that direction.”

Complete Story