On 06/13/2011 05:39 PM, Kent Borg wrote: > I was assuming that drivers, responding to an interrupt from some > external event, would want to make this call. > Such as a network driver. Those already are doing this. > Two points: > > 1. Why look at the high-order bits? How are they going to have values > that cannot be inferred? If you are looking for entropy, the low-order > bits is where they're going keep it. (Think Willie Sutton.) If looking > at the low-byte is cheaper, then let's be cheap. If, however, if > looking at more bytes *is* as cheap, then there is no harm. But in any > case let's keep the code lean enough that it can be called from an > interrupt service routine. Consider the case where the TSC is running in steps of 64 and you're using the low 6 bits. -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-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
