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Message-ID: <da8150af0803100331l23aa0ac3lcd7f184156a20a56@mail.gmail.com>
Date: Mon, 10 Mar 2008 11:31:56 +0100
From: "Pierre Falda" <darkstuff@gmail.com>
To: linux-kernel@vger.kernel.org
Subject: dev_queue_xmit question
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Hi,

I apologize whether this question has been asked already, however I
performed a check on the archives and didn't find anything suitable to
my case.

I would like some enlightenment about dev_queue_xmit use:

The man page explains that the buffer is being 'consumed', however I
can increase the reference count value in order to attempt a resend.

Does this mean that I should proceed this way (see code below) in case
I am willing to send the same skb more than once (ie, multiple times)?



***********************************************************************
...
...

while(i want to send this skb)
{

       skb_get(skb)

       skb->dev = output_device;

       skb->packet_type = PACKET_OUTGOING;

        xmit_rvalue = dev_queue_xmit(skb)

        if(xmit_rvalue) /* != 0 not successful send */

                goto error;

}

       return (0);

error:

     dev_kfree_skb(skb);

     return (-1);

***********************************************************************

So, is it okay or this piece of code and technique should be used only
in case of skb transmission error?

In short, what I would like to obtain is avoiding a (p)skb_copy
overhead before the dev_queue_xmit call.

Thank you in advance :)

Pierre