timing of inb/outb, cpu dependent ?

Paul Barton-Davis (pbd@Op.Net)
Tue, 21 Jul 1998 16:13:08 -0400

is the elapsed time for an inb or outb operation CPU dependent, or a
function purely of bus speed ? I have a loop which looks like:

for (i = 0; i < current_cpu_data.loops_per_sec/SOME_CONSTANT; i++) {
if (inb (port) == SOME_VALUE) {
break;
}
}

clearly, the iterative part of the loop is completely CPU dependent,
hence to use of current_cpu_data.loops_per_sec, but I'm unclear on how
much the elapsed time of this loop might vary according to the time it
takes to run inb/outb.
--pbd

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