Re: RT and timers

[Thomas Gleixner]

On Thu, 2005-06-09 at 18:36 -0700, George Anzinger wrote:
> > I'm mainly concerned because that loop never breaks . It seems like there 
> > could be a condition when the loop never stops. For instance , a very 
> > accurate timer interrupt, and timers that continually reset themselves.
> 
> As I recall, it is not possible to put a timer in the list for the current time. 
>   It will be put in the next tick slot or, with HRT, be passed to the hrt code. 
>   The only case this might fail is if a kernel hrt user restarts his timer for 
> "now" or prior to "now".  This is bad and hard to correct.  The posix-timers 
> code does not restart timers until the signal is delivered and then from the 
> user thread, not the softirq context.
> 
> Did I miss something here?

No, you're right. Expired timers are inserted into the next slot, so the
loop is not able to starve itself.


tglx


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