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Subject: Re: [RFC] mac80211: use rhashtable for station table
From: Johannes Berg <johannes@sipsolutions.net>
To: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Cc: "linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>,
	Thomas Graf <tgraf@suug.ch>
Date: Mon, 23 Feb 2015 23:01:36 +0100
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On Mon, 2015-02-23 at 22:52 +0100, Johannes Berg wrote:

> We also can't rely on 4-byte alignment though, so perhaps we should do
> something like
> 
> u32 sta_info_hash(void *addr, u32 len, u32 seed)
> {
> 	u16 *a = addr;
> 
> 	return jhash_3words(a[0], a[1], a[2], seed);
> }

Or better do

	return jhash_2words(addr[0], (addr[1] << 16) | addr[2], seed);

since I have no idea how the missing high 16 bits would behave.
(we can rely on 2-byte alignment, but not 4-byte)

johannes