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From: Rainer Weikusat <rweikusat@mssgmbh.com>
Newsgroups: comp.unix.programmer,comp.programming
Subject: Re: weighted-fair queuing
Date: Fri, 21 Oct 2011 00:51:20 +0100
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"Mark" <mark_cruzNOTFORSPAM@hotmail.com> writes:

[...]

> Weights that can be assigned by user from upper layer software are in range 
> 1-32, the max weight value in h/w is 131072, therefore I need some way to 
> scale down input value (1-32) to properly fit in the hardware.

This looks rather as if you would need to scale it up. Given that you
need to map a value in the range (1, 2^5) [2^5 ::= 2 to the fifth
power] to the range (0, 2^17), an obvious idea would be

static inline unsigned map_weight(unsigned weight)
{
	return weight * (1 << 12);
}

(since 2^17/2^5 = 2^12, 131072 / 32 = 4096).