Re: RTLinux patch (was RE: [microblaze-uclinux] Implementing FAT on uCLinux)

[Alejandro Lucero <alucero@xxxxxxxxx>]

On Tuesday 16 January 2007 08:57, Brettschneider Falk wrote:
> Hi Alejandro,
> thanks for your reply.
> It sounds like with this stuff, a user program can't use poll() to wait for
> interrupt "events" but gets interrupt notification directly by the RTLinux
> management, passed around the kernel, right? 

User programs can use whatever they use with usual Linux systems, since the 
virtualizarion is hidden to Linux. Other thing is the time lapsed since the 
interrupt occurs until program user "knows" that. With RTLinux/Linux you can 
have RT drivers and Linux drivers. Although you can have the same device 
working for RT and Linux, this is not the usual case and it has some 
drawbacks to take into account. 

> My impression of your detailed 
> description: The kernel (drivers) shouldn't be used for connecting
> interrupts to the user program, but only for slow and not time-critical
> stuff because it's constantly scheduled as task with the lowest priority in
> the whole system. Right? Yes, I should read some docu...
> CU, F@lk

Yes, you are right.

Regards.

>
> Alejandro Lucero wrote (January 10, 2007 4:49 PM)
>
> > It's necessary to make the difference between RTLinux and
> > real time Linux
> > patches.
>
> ...8<.....8<.....8<...
>
> > I hope this explanation can help you.
>
> ___________________________
> microblaze-uclinux mailing list
> microblaze-uclinux@xxxxxxxxxxxxxx
> Project Home Page : http://www.itee.uq.edu.au/~jwilliams/mblaze-uclinux
> Mailing List Archive :
> http://www.itee.uq.edu.au/~listarch/microblaze-uclinux/

-- 
Alejandro Lucero
Director Técnico
+34 665 68 71 68
Valencia (SPAIN)
www.os3sl.com

___________________________
microblaze-uclinux mailing list
microblaze-uclinux@xxxxxxxxxxxxxx
Project Home Page : http://www.itee.uq.edu.au/~jwilliams/mblaze-uclinux
Mailing List Archive : http://www.itee.uq.edu.au/~listarch/microblaze-uclinux/