From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] net_tx_action: Call trace_consume_skb() instead of
 trace_kfree_skb()
Date: Wed, 12 Sep 2012 15:39:49 +0200
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	davem@davemloft.net
To: Shawn Bohrer <sbohrer@rgmadvisors.com>
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On Wed, 2012-09-12 at 08:20 -0500, Shawn Bohrer wrote:

> But I guess your question is who puts the skb on the completion_queue.
> In my case it looks like:
> 
> dev_kfree_skb_irq()
> dev_kfree_skb_any()
> mlx4_en_free_tx_desc()
> mlx4_en_process_tx_cq()
> mlx4_en_xmit()
> dev_hard_start_xmit()
> # from here up the stack there seems to be several paths one of which is
> dev_queue_xmit()
> ip_finish_output()

> Does this answer your question about how I'm hitting this tracepoint?

Yes : this driver can do TX completion from its start_xmit() as well...


We need to add new helpers for dev_kfree_skb_any() and
dev_kfree_skb_irq(), but its quite a lot of work.

An alternative would be to set a bit in skb (skb->consumed)