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Re: Thread suspend when scheduler is locked.
Nick Garnett <nickg@calivar.com> writes:
> On 21/06/12 12:51, Sergei Organov wrote:
>> Nick Garnett <nickg@calivar.com> writes:
>
>>> Essentially locking the scheduler yourself is like running in a DSR,
>>> there is only a limited number of calls it makes sense to use, and their
>>> effects may be deferred until the scheduler lock returns to zero.
>>
>> So, there is no way in eCos to just disable _preemption_? I.e.,
>> (temporarily) switch from preemptive to cooperative multi-threading?
>
> Not really. You could try implementing a new scheduler that only did
> context switches when a yield function is called. If you disable
> timeslicing and run all your threads at the same priority they will
> essentially run round-robin and only lose the CPU when they explicitly
> suspend, although higher priority threads will still preempt.
No, I need full-featured preemptive scheduling with multiple real-time
thread priorities. I thought "disable preemption" feature is pretty
standard among RTOSes and have it in my RTOS abstraction layer,
implemented as a call to cyg_scheduler_lock() in eCos as disabling
preemption is what description of the call claims.
In fact I use this feature for very special purpose and can re-design my
code to avoid it.
-- Sergei.
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