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[linux-dvb] Re: Losless Section Demux version 1.4



Emard wrote:
Crc check can't be done there because the crc engine cannot access
system ram but only demux ram. memcopy wasn't used to always copy a
complete section before, but it didn't copy more than one section. A
quick grep shows me, that our driver is the only one available that uses
the hardware acceleration callbacks. If we keep the current situation,
then we could just remove these callbacks because they were rendered
useless.

OK, let's dig out old code and I'll browse my files for
the oldcode fix patch and we can keep both versions in the kernel, with the nodule option which one to use.

modprobe dvb-core old_section_demux=1
No, please fix the code. Either the new or the old one. Otherwise we have two broken imeplementations to choose from.

The memcpy() issue should not be too hard to resolve, just never copy more than a complete section and reset the crc seed appropriatly. The performance impact should be negligible.


The new code reduces the number of memcopy's. Depending on TS stream,
it could sometimes deliver many sections with a single memcopy.
And that's what broke the hardware accel callbacks. And remember you are
using those PCI cards which probably sit in a system with GHz Pentiums.
Think about embedded systems like ours with 66 MHz where doing crc32 in
software really slows things down.

OK, let's have both of them codes and allow too choose
nope.

Holger



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