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Subjectqueuing & scheduling hints needed
Linux kernel I have:
2.0.x - I can upgrade if needed
device:
PCI bus to VME bus adaptor of bit3 ( model 617 ) for physics
problem:
writing driver for the device with mmap & DMA together, when DMA
demands cease of all the other activities on the device ( on the
bus-to-bus cable ) incl interrupts.
my experience:
SunOs drivers for different SPARCS ,also for VME adaptors on SPARC.
Slow control & data acquisition for physics
Linux Kernel Beginner
my question:
asking good hints in queuing & scheduling & process control
------------------------------------------------------------
Dear Linux Gurus,
I have a device which is nice to write a driver to, except
for one thing. The device has it's own DMA engine.For the
duration of it's DMA all the other activity have to cease.
On the other side, the device allows to build VME bus access
on PC, using mmap for slow control access ( several addresses)
and read/write DMA access over several base VME spaces with
lseek to set the DMA address.

I can get the table of my user-processes collected them from the
open/mmap calls in my driver. My question is how to put them to
a short nap during my DMA in the most linux-like elegant way.

After a bit more reading of kernel I can hack my way with
the ax through tq_xxx queues of the sched.c, may be copying
a bit of code. May be I will learn on time how to (un)mark them
as awaiting I/O. I would like the kernel to do most of the job.
Certainly you can give me a hint how to achieve my goal by
something elegant & quick. I would also welcome recommendation
of a good book concerning kernel services. I am using the kernel
code and Linux Kernel Hacker's guide if Michael K.Johnson
obtained from the net (+ several articles found also there).
It's good, but I miss the index.

Sincere greetings from your Linux Kernel Beginner
Nata


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