27 Nov
2005
27 Nov
'05
2:45 p.m.
On 27/11/05, Mark Knecht <markknecht(a)gmail.com> wrote:
On 11/27/05, Pete Leigh <pete.leigh(a)gmail.com>
wrote:
> Didn't Clemens Ladisch write a (now outdated)
patch to re-assign
> APIC priorities in software, and a program to change PIC interrupt
> priorities?
For APIC - yes
For PIC - no
Oh, perhaps I misread at
http://users.informaik.uni-halle.de/~ladischc/pic_priorities.html
where he says:
(quote on)
To configure the PIC, use the following little program:
set8259priorities.c (source code only).
[...]
The above example configuration with interrupt 5 at the
top can be set with "set8259priorities 5 8". For interrupt 11
at the top, run "set8259priorities 2 11".
(quote off)
Or perhaps I didn't understand what he was saying. It seems
to be saying that the PIC controller can be programmed to
some extent from software, at least in principle (perhaps it
needs some hardware support?)
> Is the latter an intrinsically inferior solution?
I didn't follow. Sorry.
I meant to ask: is using the irq handling thread priority control
from the rt kernel patches necessarily a worse way to go about
things than hardware re-prioritisation?
Cheers,
- Pete.