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Re: What means of word 'quesue' in this RTOS description?

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Tim Wescott wrote:
> On Fri, 24 Jul 2015 20:52:51 -0500, Les Cargill wrote:
>
>> Tim Wescott wrote:
>>> On Fri, 24 Jul 2015 04:12:23 -0700, Robert Willy wrote:
>>>
>>>> Hi,
>>>>
>>>> I read an online tutorial on RTOS, see below dot line please.
>>>> I am not clear about what is for the word 'queue' in the first line.
>>>> Does it mean a task queue?
>>>>
>>>>
>>>> Thanks in advance.
>>>> ....................
>>>> The use of a queue allows the medium priority task to block until an
>>>> event causes data to be available - and then immediately jump to the
>>>> relevant
>>>>    function to handle the event. This prevents wasted processor cycles
>>>>    -
>>>>    in contrast to the infinite loop implementation whereby an event
>>>>    will only be processed once the loop cycles to the appropriate
>>>>    handler.
>>>
>>> I'm not sure what you mean by "task queue".
>>>
>>> Generally, RTOS implementations don't bind a queue to any specific
>>> task. Rather, the developer does so: anything can put messages into a
>>> queue, anything can take messages off of a queue, and anything can pend
>>> on a queue.  If the developer is wise, only one task takes things off
>>> the queue, and there is a well-defined, small number (one is best) of
>>> sources that put things on the queue.
>>>
>>> You arrange things so that the task that depends on the queue needs to
>>> run if and only if there's a message on the queue, and you have the
>>> task pend on the queue having a message available.
>>>
>>>
>> One common method of referring to task/thread eligibility to run is to
>> have a "ready queue" or a "waiting queue". This may not actually be a
>> queue; it can be nothing more than a state in the set of task control
>> blocks.
>>
>> Vhttp://www.qnx.com/developers/docs/660/index.jsp?topic=%
> 2Fcom.qnx.doc.neutrino.prog%2Ftopic%2Foverview_Ready_queue.html
>
> That's not what the OP is talking about,


Then I have no hope of finding what he's talking about.

1) "The use of a queue allows the medium priority task to block until
an event causes data to be available" - mention of blocking, which is
very much a "waiting queue"/"ready queue" sort of thing, although
you have to wonder why medium priority matters.

The big ambiguity is whether or not the queue is a data source/buffer
or simply a wait/block structure.

2) The compare/contrast with The Big Loop.

wait/ready queuing is as close as I can get with that mess.

 > but yes, I had forgotten that
> terminology (please, please do not ask me why).
>

:)

-- 
Les Cargill

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Thread

What means of word 'quesue' in this RTOS description? Robert Willy <rxjwg98@gmail.com> - 2015-07-24 04:12 -0700
  Re: What means of word 'quesue' in this RTOS description? Les Cargill <lcargill99@comcast.com> - 2015-07-24 07:47 -0500
  Re: What means of word 'quesue' in this RTOS description? Tim Wescott <seemywebsite@myfooter.really> - 2015-07-24 13:59 -0500
    Re: What means of word 'quesue' in this RTOS description? Grant Edwards <invalid@invalid.invalid> - 2015-07-24 19:34 +0000
    Re: What means of word 'quesue' in this RTOS description? Les Cargill <lcargill99@comcast.com> - 2015-07-24 20:52 -0500
      Re: What means of word 'quesue' in this RTOS description? Tim Wescott <seemywebsite@myfooter.really> - 2015-07-24 22:18 -0500
        Re: What means of word 'quesue' in this RTOS description? Les Cargill <lcargill99@comcast.com> - 2015-07-26 09:27 -0500
          Re: What means of word 'quesue' in this RTOS description? Don Y <this@is.not.me.com> - 2015-07-26 08:51 -0700
          Re: What means of word 'quesue' in this RTOS description? Tim Wescott <seemywebsite@myfooter.really> - 2015-07-26 16:23 -0500
    Re: What means of word 'quesue' in this RTOS description? upsidedown@downunder.com - 2015-07-25 08:57 +0300
  Re: What means of word 'quesue' in this RTOS description? Don Y <this@is.not.me.com> - 2015-07-24 12:34 -0700
    Re: What means of word 'quesue' in this RTOS description? Robert Willy <rxjwg98@gmail.com> - 2015-07-24 14:03 -0700
      Re: What means of word 'quesue' in this RTOS description? Don Y <this@is.not.me.com> - 2015-07-24 14:37 -0700

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