[ECOS] Multi-Threaded Program in eCos

[ECOS] Multi-Threaded Program in eCos

[Timothy Chow]

Hello,

I am working on a custom SA1100-based device running
eCos. I have some problem with multi-threaded
programs.

I usually have 4 or more threads in a program. Some of
them are threads for device drivers, so usually they
are all endless loops (i.e. while(1) {...}).

I have the same priority for every thread, but
difference thread delay for the while loop in each
thread. Even if a thread/loop needs to run
continuously, I will add "cyg_thread_delay(1)" after
each loop to let the scheduler run.

The problem is, some threads with greater thread delay
will stop totally after a while, and only those
threads with smaller delay will keep running. The
funny thing is those "stopped" threads will "resume"
and run like the normal way after being stopped for a
while. And the cycle goes on ...

Any suggestions?


Thanks,
Tim

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Re: [ECOS] Multi-Threaded Program in eCos

[Rafael Rodríguez Velilla]

Timothy Chow wrote:

> Hello,
>
> I am working on a custom SA1100-based device running
> eCos. I have some problem with multi-threaded
> programs.
>
> I usually have 4 or more threads in a program. Some of
> them are threads for device drivers, so usually they
> are all endless loops (i.e. while(1) {...}).
>
> I have the same priority for every thread, but
> difference thread delay for the while loop in each
> thread. Even if a thread/loop needs to run
> continuously, I will add "cyg_thread_delay(1)" after
> each loop to let the scheduler run.

  Why don't you use cyg_thread_yield() instead of cyg_thread_delay. In this
way, once a thread has completed its work it will rotate in the queue of
threads of the same priority.