PPP2 driver interface_pp.c overhaul

[Bas Rijniersce]

Hi,

Peter Pregler wrote:
 
> On 29-Aug-99 Peter Pregler wrote:

> > That is true. There is a busy-wait in the kernel-code (the WHILE_OUT macro).
> > I
> > have a patch that utilizes the scheduler task-queu. Note that
> > interrupt-driven
> > code is not the solution here. The busy wait is while waiting for data on the
> > parallel port and not while waiting for a picture. Unfortunatly my code has
> > still some problem if interrupted (I am new to kernel-hacking ;). I will
> > debug
> > this and than send the patch to the list. This should happen until Tuesday
> > this
> > week.
 
> Okay, here is the patch as promised. The patch is against the original
> cpia-0.2. It is using a timer and not a task queue but who cares. I was not able
> to crash my machine anymore. So it might be stable. Use at your own risk and
> don't assume it is SMP-safe. Has anyone a good description about programming
> kernel-modules that are SMP-safe? That chapter is empty in the kernel-module
> programming guide.

Ofcourse I just closed my eyes and applied the patch... Now the CPU
usage is down to 9-10% in top. I don't notice any slowdowns at all.
Thanx !!
I'll try to merge your patch with Scott's patch and let it run for a
while, so if it stable... When that's all stable i'll try to hack a
small program together that writes an image to file every few seconds so
that I can run it as a webcam ;-)

 > As for resource consumption: I had a closer look and the numbers were
about 9%
> in kernel mode for reading data and about 30% in user-mode decoding. All done
> on a PII-350 with linux-2.2.12, size cif, thresholds set to 10, autocompression
> resulting in about 4 fps. So there was pretty much data going over the parport.

On my dual celeron 500, linux-2.2.12 with the same settings also a
framerate of 4-5 fps.
 
> Greetings, Peter

Bas

----
Bas Rijniersce                       Phone +31 341 550545
Oude Telgterweg 81                   Fax +31 341 562940
3851 EA  Ermelo                      http://www.brijn.nu
The Netherlands                      bas@brijn.nu
-----------------------------------------------------------------------------
To unsubscribe from this mailinglist, send the line "unsubscribe vision-webcam" in the
body of a message to "majordomo@errors.no".