netdev - Re: [PATCH] net/core/flow.c: compare data with memcmp

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Date:	Mon, 01 Jan 2007 00:49:05 -0800 (PST)
From:	David Miller <davem@...emloft.net>
To:	daniel.marjamaki@...il.com
Subject: Re: [PATCH] net/core/flow.c: compare data with memcmp

From: "Daniel_Marjamäki" <daniel.marjamaki@...il.com>
Date: Mon, 1 Jan 2007 08:47:48 +0100

> So you mean that in this particular case it's faster with a handcoded
> comparison than memcmp? Because both key1 and key2 are located at
> word-aligned addresses?
> That's fascinating.

Essentially, yes.

However, I wonder.  GCC should be able to see this also, and
if it expands the memset() inline the code emitted should be
very similar.

It is something to investigate on a few cpu types, for sure.
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