Re: early printk timings way off

From: Tim Schmielau
Date: Fri Sep 16 2005 - 12:25:31 EST


On Fri, 16 Sep 2005, Tim Schmielau wrote:

> So, one jump (probably the first) happens when time_init sets use_tsc.
> Do we understand the other jump as well?

OK, looking at the numbers we have just one time-jump:

> [4294667.296000] CPU 0 irqstacks, hard=c03d2000 soft=c03d1000
> [4294667.296000] PID hash table entries: 2048 (order: 11, 32768 bytes)
> [ 0.000000] Detected 1400.279 MHz processor.
> [ 27.121583] Using tsc for high-res timesource
> [ 27.121620] Console: colour dummy device 80x25
> [ 27.122909] Dentry cache hash table entries: 131072 (order: 7, 524288

The "Detected 1400.279 MHz processor." line just happens to be written
_during_ time_init, when use_tsc is already set, but cycles_2_ns is not
yet initialized.

So I think everything is well-understood. It's just a matter of whether
it's worth fixing.

Tim
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