On 2/10/07, Curran, Dominic <dcurran@xxxxxx> wrote:
>
> > Hello. I have written a netfilter kernel module and I want some code
> > to run periodically, ie a function in the module should run every 5
> > seconds.
> >
> > I have researched and implemented a kernel work queue however this
> > does not have the capability of being periodic from my assessment.
> > Can anyone point me in the right direction?
> >
>
> i've read all messages in this thread and seems the only way proposed
> is using timers...
>
> i've implemented a very similar kernel module, using netfilter to
track
> connections, and i created a kernel tread that detect inactivity in a
> loop, and sleeping for a while in between.
>
> this solutions will work for you? :)
>
> or maybe i'm doing a very ugly thing? :(
>
The original poster asked for code to run periodically. From that I
assumed he meant every X number of jiffies.
Using timers will give him pretty good accuracy in that respect.
What mechanism are you using to sleep and wake yourself up within your
thread ?
If you are using schedule() to sleep and then testing if > X jiffies has
passed then this will also work.
e.g.
while( !exit )
{
start = jiffies;
do {
schedule();
} while( jiffies - start < X );
Use time_after/time_before, as this direct comparison will miss wraps.
Thanks,
Nish
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