Re: [Fwd: Re: [patch] Real-Time Preemption, -RT-2.6.9-mm1-V0.4]

From: Ingo Molnar
Date: Fri Oct 29 2004 - 11:34:41 EST



* Ingo Molnar <mingo@xxxxxxx> wrote:

> the BKL can generate arbitrary latencies. Anything up to 100-200
> milliseconds. Rui, Florian, could you try the quick hack below?

hm, this alone probably wont work, because the audio layer does
unlock_kernel() in many places.

could you try another hack in addition to the ioctl.c hack, save the
attached script, and do this in your Linux source tree:

cd sound
~/changeall-tree "unlock_kernel()" ""
~/changeall-tree "lock_kernel()" ""

(in strictly this order.) This gets rid of the BKL from the sound
subsystem in quite drastic ways... Totally untested, so be careful ...

Ingo

#!/bin/bash

if [ $# -lt "2" ]; then
echo 'usage: changeall <from> <to>'
exit -1;
fi

echo "changing $N => $N"

for N in `find . -type f`; do
echo $N;
cat $N | sed "s/$1/$2/g" > .tmp; mv .tmp $N;
done