pskb_copy() in tcp_transmit_skb()

Hi,

I'm trying to understand the reason for the possible call to pskb_copy() in 
tcp_transmit_skb().
I don't find, where we may have a cloned skb entering tcp_transmit_skb().

The original pskb_copy() came from tcp_retransmit_skb() (commit 
dfb4b9dceb35c567a595ae5e9d035cfda044a103).
But from that point, the git-history does not show where the pskb_copy() is 
coming from.


Does somebody has an idea, how a cloned skb can be passed to 
tcp_transmit_skb() and thus trigger this call to pskb_copy().


Thanks for your help,
Christoph


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Christoph Paasch
PhD Student

IP Networking Lab --- http://inl.info.ucl.ac.be
MultiPath TCP in the Linux Kernel --- http://inl.info.ucl.ac.be/mptcp
Université Catholique de Louvain

www.rollerbulls.be
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