Re: [patch] Real-Time Preemption, -RT-2.6.10-rc2-mm3-V0.7.32-6

[Steven Rostedt <rostedt@goodmis.org>]

On Thu, 2004-12-09 at 12:10 -0600, Mark_H_Johnson@raytheon.com wrote:
> >but you never want your real application be delayed by things like IDE
> >processing or networking workloads, correct?
> For the most part, that I/O workload IS because I have the RT application
> running. That was one of my points. I cannot reliably starve any of
> those activities. The disk reads in my real application simulate a disk
> read from a real world device. That data is needed for RT processing
> in the simulated system. Some of the network traffic is also RT since
> we generate a data stream that is interpreted in real time by other
> systems.

[RFC]  Has there been previously any thought of adding priority
inheriting wait queues. With the IRQs that run as threads, have hooks in
the code that allows a driver or socket layer to attach a thread to a
wait queue, and when a RT priority task waits on the queue, a function
is call to increase (if needed) the priority of the attached thread. I
know that this would take some work, and would make the normal kernel
and RT diverge more, but it would really help to solve the problem of a
high priority process waiting for an interrupt that can be starved by
other high priority processes.

Just a thought.

-- Steve