From: Sergei Organov <osv@javad.com>
To: ecos-discuss@sources.redhat.com
Subject: [ECOS] Re: Thread suspend when scheduler is locked.
Date: Thu, 21 Jun 2012 11:51:00 -0000 [thread overview]
Message-ID: <jrv1rp$2t0$1@dough.gmane.org> (raw)
In-Reply-To: <4FE2F84F.2040801@calivar.com>
Nick Garnett <nickg@calivar.com> writes:
> On 21/06/12 10:00, Sergei Organov wrote:
>> A few clarifications below.
>>
>> Sergei Organov <osv@javad.com> writes:
>>> Hello,
>>>
>>> In the following sequence:
>>>
>>> cyg_scheduler_lock();
>>> cyg_thread_suspend(thread);
>>>
>>> the second call returns immediately that is very surprising. Is it a bug
>>> or fature?
>>
>> 1. 'thread' is the current thread being executed so the suspend call asks
>> thread for suspending itself.
>>
>> 2. cyg_thread_delay(delay) returns immediately no matter what is 'delay'
>> value.
>>
>> 3. On the other hand, waiting on a primitive such as closed semaphore
>> works fine.
>>
>> Looks like a bug to me.
>
>
[...]
> 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?
-- Sergei.
--
Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos
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next prev parent reply other threads:[~2012-06-21 11:51 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-20 18:23 [ECOS] " Sergei Organov
2012-06-21 9:00 ` [ECOS] " Sergei Organov
2012-06-21 10:33 ` Nick Garnett
2012-06-21 11:51 ` Sergei Organov [this message]
2012-06-21 12:48 ` Nick Garnett
2012-06-21 14:57 ` Sergei Organov
2012-07-01 2:45 ` Jonathan Larmour
2012-07-02 10:13 ` Sergei Organov
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