Whether the event in the queue of scheduler have different priority?

RE: Whether the event in the queue of scheduler have different priority?

Chaoyue Ying — Thu, 29 Feb 2024 00:21:17 GMT

Hi,

I only need a small number of different priorities.

The method that with three levels is seem suitable for me.But how to realize three queues?If I need to change the code of schedule?Or just by other ways?

RE: Whether the event in the queue of scheduler have different priority?

Daniel Chisholm — Wed, 28 Feb 2024 13:13:37 GMT

Hi, do you need to have a large number of different priorities, or do you only need a small number of different priorities?

(Forgive me if I am mixing up Zephyr message queues with the "app scheduler" queue..)

If you need say three different priority levels ("low, medium, high"), what about creating three queues:

when you queue an item, put it in the desired queue
when your servicing routine is available to process work, take the next available item from the highest-priority queue

RE: Whether the event in the queue of scheduler have different priority?

Einar Thorsrud — Wed, 28 Feb 2024 11:34:57 GMT

I suspect it will be more work than just adding a few fuctions, but this will be up to you. I do not have any advice on how to implement it. (My suggestion is to use an existing RTOS scheduler like what you have in FreeRTOS if you need these features).

RE: Whether the event in the queue of scheduler have different priority?

Chaoyue Ying — Wed, 28 Feb 2024 08:04:07 GMT

So the method that I break up earlier can be done by add some functions?

RE: Whether the event in the queue of scheduler have different priority?

Einar Thorsrud — Wed, 28 Feb 2024 08:00:06 GMT

I see. My recomendation would be to use an existing RTOS scheduler if that is what you need instead of implementing yourself (which this will be in practice, though you plan to start of with the app scueduler library we provde). You are of course free to do this, but it will be up to you.

RE: Whether the event in the queue of scheduler have different priority?

Chaoyue Ying — Wed, 28 Feb 2024 00:14:34 GMT

After call app_sched_pause(),I want to operate m_queue_event_data and m_queue_event_headers to add schedule as app_sched_event_put(),but the data write at the head of queue.So that when I restart scheduler,app_sched_execute() will deal the data that I write first.

RE: Whether the event in the queue of scheduler have different priority?

Einar Thorsrud — Tue, 27 Feb 2024 08:19:01 GMT

I am not sure I understand what you mean and how this will give you something like priorities? But regarding pausing the scheduler, the app scheduler is run by calling app_sched_execute(). If you don't call it, the scheduler will not run. When called, all task are run, but you can call app_sched_pause() to stop processing at any time (call app_sched_resume() to resume it).

RE: Whether the event in the queue of scheduler have different priority?

Chaoyue Ying — Tue, 27 Feb 2024 00:19:18 GMT

Whether We can operate the queue of scheduler to save data and handler ? Maybe I can pause schedule and write data into the header,then restart schedule to realize similar to the effect of priority?

RE: Whether the event in the queue of scheduler have different priority?

Einar Thorsrud — Mon, 26 Feb 2024 08:17:48 GMT

Not in what we provide, no. I know you wrote that you don't want to use FreeRTOS, but a scheduler with priorities is the most important feature of an RTOS, so if you really need it, I would consider an RTOS. If you have not gotten far with your development, I woudl also take the opportunity to consider using the nRF Connect SDK insted of the old nRF5 SDK (see also nRF Connect SDK and nRF5 SDK statement).

RE: Whether the event in the queue of scheduler have different priority?

Chaoyue Ying — Mon, 26 Feb 2024 00:08:43 GMT

Hi,

if there have method to dupport for priorities?I need a method to realize it.

RE: Whether the event in the queue of scheduler have different priority?

Einar Thorsrud — Fri, 23 Feb 2024 13:40:54 GMT

Hi,

The app scheduler does not have support for priorities. You can think of it as a simple FIFO with a function pointer and some metadata. The sole pruprose of this scheduler library is to move ececutions from interrupts to the main context.