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

Related Stories:

• Selecting and Tuning a Scheduler(May 11, 2009)
• That massive filesystem thread(Apr 16, 2009)
• Interview: the return of the realtime preemption tree(Feb 27, 2009)
• Kernel Space: The Enterprise Real-Time Feud(Dec 12, 2007)