From mboxrd@z Thu Jan  1 00:00:00 1970
From: Johann Baudy <johann.baudy@gnu-log.net>
Subject: Re: [PATCH] TX_RING and packet mmap
Date: Tue, 21 Apr 2009 23:13:22 +0200
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To: Christoph Lameter <cl@linux.com>
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> Doesnt the kernel need some way to synchronize the two
> transitions made by the kernel? From "send request" to "sending" and then
> to "available"? Otherwise the kernel may set the request to "available"
> before the change from "send request" to "sending" is complete.

This synchronization is performed through skb mechanism.
"send request" to "sending" is done before submitting skb to device.
"sending" to "available" will be performed in skb destructor.