Message-ID: <20010920032040.14252.qmail@web11507.mail.yahoo.com>
Date: Wed, 19 Sep 2001 20:20:40 -0700 (PDT)
From: Guilhem Tardy <guilhem_tardy@yahoo.com>
Subject: Re: 3c59x.c modified for time measurement / code included
To: Donald Becker <becker@scyld.com>
Cc: netdev@oss.sgi.com, andrewm@uow.edu.au, greearb@candelatech.com
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> If you are accessing a 32 bit number, you should use a "naturally
> aligned" address.  In your previous example you were using
> (int *)(base + 21)
> If "base" is aligned, base+21 will be misaligned for all but byte accesses.

Then I should be fine, as my original code read:
*(((unsigned int *) (skb->data+20)) + 1)

I was under the assumption that int was 16 bits on x86, but Rene corrected me
("int = 32Bit @ linux"). I will test the code modified with u16 first thing in
the morning tomorrow. In all cases, the "+1" above refers to a pointer of
unsigned int, then alignment should be OK, right?

Thanks for the input. I hope not to bother anyone with that after tomorrow. :)
As a last resort, I will add some heuristic to find the port number in the
packet and start from there.

Guilhem.


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