From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: STM32F4 Discovery, communication and libraries
Date: Mon, 1 Sep 2014 18:42:23 +0200
Date: 2014-09-01T18:42:23+02:00 [thread overview]
Message-ID: <1mjah4ljimdm3$.u606f5alc3hx$.dlg@40tude.net> (raw)
In-Reply-To: XY0Nv.192696$4%3.170932@fx10.iad
On Mon, 01 Sep 2014 10:15:52 -0600, Brad Moore wrote:
> On 2014-08-31 10:15 AM, Dmitry A. Kazakov wrote:
>> On Sun, 31 Aug 2014 09:44:26 -0600, Brad Moore wrote:
>>
>>> On 2014-08-31 1:02 AM, Dmitry A. Kazakov wrote:
>>
>>>> When I evaluated Ravenscar for our middleware (long ago), the concern was
>>>> publisher/subscriber services. I/O queue viewed as one of them. I didn't
>>>> consider a solution like yours because the requirement was that more than
>>>> one task could await for same I/O event. You reserve the event for single
>>>> task and other publisher/subscriber services (e.g. the data logger, network
>>>> data server, health monitor etc) may not use it because of
>>>> Max_Protected_Entries = 1. The event cannot propagate because of
>>>> No_Requeue_Statements. Tasks could flood the queue with their
>>>> requests/events but they cannot do that for more than one queue.
>>>
>>> I don't see this is an obstacle for Ravenscar. The clients could
>>> register their interest in an event type by passing in a reference to
>>> their IO_Response_T object, and when an event of that type occurs, the
>>> server could call 'Set' on the list of all registered IO_Response_T
>>> objects associated with that I/O event type.
>>
>> You mean one request queued in several queues? This would have a race
>> condition and also have no guarantee that no event is lost. The schema has
>> a procedure to pulse the event, as the entry is already spent. So the stuff
>> will leak.
>
> No, I mean one request queued in one queue, where the processing of that
> request involves calling registered callbacks in some callback list for
> other clients that are interested in hearing about the servicing of that
> request.
OK. You don't need to care about Ravenscar if you use synchronous
callbacks.
--
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de
next prev parent reply other threads:[~2014-09-01 16:42 UTC|newest]
Thread overview: 93+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-08-26 22:38 STM32F4 Discovery, communication and libraries roy.emmerich
2014-08-27 2:40 ` Luke A. Guest
2014-08-27 12:35 ` Roy Emmerich
2014-08-27 7:41 ` Dmitry A. Kazakov
2014-08-27 13:35 ` Roy Emmerich
2014-08-27 16:00 ` Dmitry A. Kazakov
2014-08-27 13:08 ` Dennis Lee Bieber
2014-08-27 15:44 ` Roy Emmerich
2014-08-28 1:37 ` Dennis Lee Bieber
2014-08-27 16:03 ` Roy Emmerich
2014-08-28 1:48 ` Dennis Lee Bieber
2014-08-28 10:12 ` Roy Emmerich
2014-08-28 13:00 ` Dmitry A. Kazakov
2014-08-28 16:28 ` Mike Silva
2014-08-28 17:03 ` Roy Emmerich
2014-08-28 20:09 ` Dmitry A. Kazakov
2014-08-28 20:34 ` embeddedrelatedmike
2014-08-29 7:34 ` Dmitry A. Kazakov
2014-08-29 15:59 ` Niklas Holsti
2014-08-29 16:59 ` [OT] Ravenscar (the place, not profile), was: " Simon Clubley
2014-08-29 17:18 ` Niklas Holsti
2014-08-29 17:31 ` Simon Clubley
2014-08-30 14:55 ` Dennis Lee Bieber
2014-08-29 17:59 ` Jeffrey Carter
2014-08-29 23:30 ` Randy Brukardt
2014-08-30 11:25 ` Simon Clubley
2014-08-31 11:09 ` Phil Thornley
2014-08-30 12:36 ` Peter Chapin
2014-08-31 18:37 ` Dirk Craeynest
2014-08-31 19:38 ` Simon Clubley
2014-08-29 17:24 ` Mike Silva
2014-08-29 23:35 ` Randy Brukardt
2014-08-29 13:06 ` Dennis Lee Bieber
2014-08-29 16:52 ` Niklas Holsti
2014-08-31 0:49 ` Shark8
2014-08-28 21:17 ` Niklas Holsti
2014-08-29 0:07 ` Roy Emmerich
2014-08-29 17:58 ` Niklas Holsti
2014-08-29 7:41 ` Dmitry A. Kazakov
2014-08-29 16:31 ` Niklas Holsti
2014-08-29 16:47 ` Roy Emmerich
2014-08-29 19:41 ` Niklas Holsti
2014-08-30 22:00 ` Roy Emmerich
2014-08-31 10:08 ` Simon Wright
2014-09-01 20:15 ` Niklas Holsti
2014-09-01 21:11 ` Jeffrey Carter
2014-08-31 4:54 ` gvdschoot
2014-09-09 19:17 ` Roy Emmerich
2014-09-09 20:20 ` Mike Silva
[not found] ` <a54dcc42-d4e2-4d53-b381-2bb7a0eef1ee@googlegroups.com>
2014-09-10 1:41 ` Dennis Lee Bieber
2014-09-10 8:52 ` Roy Emmerich
2014-09-10 13:05 ` Dennis Lee Bieber
2014-09-10 17:16 ` Simon Wright
[not found] ` <a2e59fce-751c-46a0-90f3-80430c627732@googlegroups.com>
2014-09-10 7:22 ` Dmitry A. Kazakov
2014-09-10 9:35 ` Roy Emmerich
2014-09-10 14:11 ` Stephen Leake
2014-09-10 17:46 ` Jeffrey Carter
2014-09-10 18:37 ` Dmitry A. Kazakov
2014-09-11 9:53 ` Stephen Leake
2014-09-11 17:19 ` Jeffrey Carter
2014-09-10 20:58 ` Brian Drummond
2014-09-10 23:40 ` Dennis Lee Bieber
2014-08-29 16:58 ` Niklas Holsti
2014-08-31 7:02 ` Dmitry A. Kazakov
2014-08-31 15:44 ` Brad Moore
2014-08-31 16:15 ` Dmitry A. Kazakov
2014-09-01 16:15 ` Brad Moore
2014-09-01 16:42 ` Dmitry A. Kazakov [this message]
2014-08-31 18:41 ` Niklas Holsti
2014-09-01 16:42 ` Dmitry A. Kazakov
2014-09-01 17:21 ` G.B.
2014-09-02 8:21 ` Dmitry A. Kazakov
2014-09-02 13:04 ` G.B.
2014-09-02 14:18 ` Dmitry A. Kazakov
2014-09-02 16:44 ` Jeffrey Carter
2014-09-02 19:02 ` Niklas Holsti
2014-09-02 23:19 ` Randy Brukardt
2014-09-03 1:40 ` gdotone
2014-09-04 9:26 ` Roy Emmerich
2014-09-04 17:58 ` Niklas Holsti
2014-09-05 11:47 ` Simon Clubley
2014-09-09 19:04 ` Roy Emmerich
2014-09-01 18:39 ` Niklas Holsti
2014-09-02 8:19 ` Dmitry A. Kazakov
2014-08-28 13:10 ` Dennis Lee Bieber
2014-08-29 2:52 ` Dennis Lee Bieber
2014-09-20 20:50 ` David Thompson
2014-08-27 16:17 ` Mike Silva
2014-08-27 16:36 ` Roy Emmerich
2014-08-27 16:58 ` Simon Clubley
2014-08-29 19:36 ` johnscpg
2014-08-30 15:06 ` Stephen Leake
2014-09-02 21:40 ` rrr.eee.27
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