Re: OpenGL-based framebuffer concepts

From: Pavel Machek
Date: Thu Jun 01 2006 - 18:21:29 EST


On Ät 01-06-06 17:48:57, Jon Smirl wrote:
> On 6/1/06, Antonino A. Daplas <adaplas@xxxxxxxxx> wrote:
> >Jon Smirl wrote:
> >> On 6/1/06, Antonino A. Daplas <adaplas@xxxxxxxxx> wrote:
> >>> Jon Smirl wrote:
> >>> > On 6/1/06, D. Hazelton <dhazelton@xxxxxxxxx> wrote:
> >>> >
> >>>
> >>> Console writes are done with the console semaphore held. printk will
> >also
> >>> just write to the log buffer and defer the actual console printing
> >>> for later, by the next or current process that will grab the semaphore.
> >>
> >> That was my original position too. But Alan Cox has drilled it into me
> >> that this is not acceptable for printks in interrupt context, they
> >> need to print there and not be deferred.
> >>
> >
> >Just to clarify, it's not my position, that's how the current printk code
> >works.
>
> I haven't looked at the code, but if there is just normal console
> running and nothing like X is around, doesn't the console system
> always have the semaphore?

Not if foreground code is already printing something. Fortunately we
do not spend most of time printing text; that's why printk from
interrupt usually works.

Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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