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Re: timer irqs when no preemption

2007/2/5, Rajat Jain <rajat.noida.india@xxxxxxxxx>: 
> > Another question - the irqs are disabled at times (like when a
> > spinlock is held). Does this cause any lost timer ticks?
> >
>
> I guess so.
>

Won't this mean a wrong value of "jiffies"?



Yes. I guess so. But I think this does not matter. The frequency of
losing timer interrupt is too low to affect the function of jiffies as
a counter. The system time is obtained from xtime (rahter than
jiffies), which is updated according to a free-source timer at each
tick, not simply added with a fixed value.

I make the above conclusion based on my own understanding. Maybe
someone more familiar with this can give more confident answer. :-)


Regards,

Rajat


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