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Subject[QUESTION] Micro-Second timers in kernel ?

I'm wondering what is the lowest resolution of timers that can
be get in Linux across all platforms. The goal : I need to do
microsecond resolution delay in the hard_xmit function of the IrDA-USB
driver, and don't want to just grab the CPU.

The function sys_nanosleep() seems to indicate that under 2ms,
we should not even bother using a timer. Well, on a modern CPU, 2ms is
a very long time (on the other hand, it seems OK for PDAs).
The definition of "tick" in timer.c indicate that the timer_bh
is called at a maximum of HZ time per second (which is consistent with
the definition of jiffies). On i386, this would be one tick every
Well... I'm stuck. 10ms is a very long time at 4Mb/s. So, I
guess I'll continue to busy wait before sending each packet. Ugh !


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