RTLinux

By Wikipedia, the free encyclopedia

http://en.wikipedia.org/wiki/RTLinux

RTLinux or RTCore is a hard realtime RTOS microkernel that runs the entire Linux operating system as a fully preemptive process.

It was developed by Victor Yodaiken (Yodaiken 1999), Michael Barabanov (Barabanov 1996), Cort Dougan and others at the New Mexico Institute of Mining and Technology and then as a commercial product at FSMLabs. Wind River Systems acquired FSMLabs embedded technology in February 2007 and now makes a version available as Wind River Real-Time Core for Wind River Linux.

RTLinux was based on a lightweight virtual machine where the Linux "guest" was given a virtualized interrupt controller and timer - and all other hardware access was direct. From the point of view of the real-time "host", the Linux kernel is a thread. Interrupts needed for deterministic processing are processed by the real-time core, while other interrupts are forwarded to Linux, which runs at a lower priority than realtime threads. Linux drivers handle almost all I/O. First-In-First-Out pipes (FIFOs) or shared memory can be used to share data between the operating system and RTCore.

Source: http://en.wikipedia.org/wiki/RTLinux