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Re: RE: Reentrancy of the ecos drivers
- From: Gary Thomas <gary at mlbassoc dot com>
- To: harbonne marc <marc dot harbonne at silicomp dot fr>
- Cc: ecos-discuss at ecos dot sourceware dot org
- Date: Tue, 18 Jul 2006 06:26:20 -0600
- Subject: Re: [ECOS] RE: Reentrancy of the ecos drivers
- References: <200607181146.k6IBkVVP015282@smtp.silicomp.fr>
harbonne marc wrote:
Hi all,
My question is quite general, I cannot see in any ecos drivers provided with
the last version of ecos, a way to protect the shared resources.
As example, if you look at any display driver, we cannot see a semaphore
that will protect from a second task to access to the resource by
pre-empting the one which has the resource.
The only call I can see is a cyg_scheduler_lock and unlock to get/release
the resource.
But in many drivers such mechanism does not exist.
Can you tell me why?
In most cases, such resource management (if it's required) is handled
at a level higher than the physical device driver.
What driver(s) are you concerned about?
--
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Gary Thomas | Consulting for the
MLB Associates | Embedded world
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