Hi
I write code for microcontroller I want to write my own scheduler for microcontroller. But I am not getting any idea even after searching a lot
scheduling is process by which operating system decide which one task will be next on processor
keep in mind I am not asking code I am looking someone who can help me to design tiny co operative scheduler
What kind of things do we put in scheduler in context of programming
No idea what you were searching for, but there's plenty to be found.
An introduction to schedulers:Co-operative and pre-emptive scheduling ~ 8051 microcontrollers
7 steps to writing a simple cooperative scheduler
> scheduling is process by which operating system decide which one task will be next on processor
That's the thing about co-operative, the OS doesn't decide.
If a task decides to not co-operate, there's nothing the OS can do.
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
If at first you don't succeed, try writing your phone number on the exam paper.
I think the first thing to do would be to figure out how context switching is going to work.
Write yourself a set of functions that do the absolute minimum scheduling: round-robin.
- Tasks are added to the end of a list through some interface. (task_add(function-pointer))
- Tasks execute until they voluntarily call "next_task()" or some such.
- Tasks can remove themselves from the list through some interface. (task_exit() or something)
- When "next_task()" is called, your code has to save the registers, save the stack, look up the next task in the list, set up the new stack, set up the registers, and return control to the new task.
That code isn't going to change much if you decide to go in a different direction with your scheduling algorithm (priorities, real-time, interrupt service, etc.)
