On 03/16/2012 02:48 AM, Thomas Gleixner wrote: >> >> Perhaps we should use the same kind of multiply-and-shift tricks we're >> doing for jiffies conversion? If nothing else it ought to perform better. > > It's not a hotpath where performance matters, but divide by zero does :) Doing the inverse multiply wouldn't have a divide by zero problem. What perhaps is more important (and the reason we went to shift-multiply) is that in addition to being faster, it also avoids unnnecessary overflows. I would really like to figure out how to do proper shift-multiply for the 64-bit jiffy conversions too. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf. -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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