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Re: Ctrl-c interrupt priority
- From: "Enrico Piria" <epiria at libero dot it>
- To: "ecos-discuss" <ecos-discuss at sourceware dot org>
- Cc: "nickg" <nickg at ecoscentric dot com>
- Date: Wed, 27 Apr 2005 15:44:34 +0200
- Subject: Re: [ECOS] Ctrl-c interrupt priority
>
> > Hello.
> >
> > On architectures supporting interrupt priority levels, at which
> > priority should the Ctrl-c ISR (the one used to bring up GDB stub)
> > be run, and why?
>
> I don't think it matters very much. Making it high priority would
> allow it to preempt any other interrupts. But to be honest, if you
> have so many lower priority interrupts firing that this actually makes
> a difference, then you probably have something seriously wrong
> somewhere.
>
The answer I gave myself, instead, was the following: the ISR should be run
at the highest maskable priority. This avoids race conditions on the
hal_saved_interrupt_state variable, that otherwise could be
rewritten by the architecture HAL interrupt handling code, during
higher priority interrupts.
Is this true?
Thanks
Enrico Piria
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