[Feature Request] Dynamic Prioritization

[svenbieg]

The problem is to define the priority on a task-level. Every task can call a critical function, so the priority has to be raised there.

My solution is a task-lock that works with a mutex. The task is marked exclusive, so interrupts are kept disabled after the task-switch until the task-lock is released.

You can take a look at the heap for example. It is used by every task and is a critical function. I'm using a task-lock there.

Best regards,

Sven Bieg

[aggarg]

Please create a post in the FreeRTOS Forums explaining your feature request in more detail, possibly with sequence diagrams to help us understand your request.

[svenbieg]

This time i'm sorry. You can find the detais here:

https://github.com/svenbieg/Scheduler

I'm happy to see You again, looking forward to my Christmas holidays. My kernel took me two weeks, it's really easy with know-how.
Your vTaskSuspendAll is too expensive, You need a mutex there that can be locked up to high priority.

Good luck, to the whole FreeRTOS-team!

I'm really sorry i don't have time at the moment,

Sven Bieg

[aggarg]

Thank you for sharing your implementation. I assume you do not need anything from FreeRTOS for your implementation as your implementation does not depend on FreeRTOS.

[svenbieg]

Semaphore sounds like a german joke.
"Seh'ma vor" is bavarian dialect for "we foresee". Mutex meaning is obvious, mutual exclusive.

[svenbieg]

You are right, exclusive mutual exclusion may sound funny at first, but it is exactly what You are missing.
If we have 100 tasks, access the heap, a high priority task is waiting, and the system timer interrupts, the high priority task has to wait for 100 task-switches.
What about mutex_lock, mutex_lock_shared and mutex_lock_up?

[svenbieg]

FIFO-task-management

[svenbieg]

Okay, i keep interrupts enabled and only block the scheduler when You call Mutex::Lock(TaskPriority::High).

https://github.com/svenbieg/Scheduler