"Chris" == Chris Friesen <[EMAIL PROTECTED]> writes:
Chris> Most cpus have some way of getting at a counter or decrementer Chris> of various frequencies. Usually it requires low-level hardware Chris> knowledge and often it needs assembly code.
As a device driver is inside the linux kernel (unless you're writein a user-mode device driver :-)) you can use the getcycles() macro that's defined for most architectures. It provides a snapshot of the cycle-counter.
For ppc this only gives 32-bit values, which overflow every 129 seconds on my G5. Depending on how long you're trying to time, this could be a problem.
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