07e1d6b3e0
Vasily Averin says:
====================
skbuff: introduce skb_expand_head()
currently if skb does not have enough headroom skb_realloc_headrom is called.
It is not optimal because it creates new skb.
this patch set introduces new helper skb_expand_head()
Unlike skb_realloc_headroom, it does not allocate a new skb if possible;
copies skb->sk on new skb when as needed and frees original skb in case of failures.
This helps to simplify ip[6]_finish_output2(), ip6_xmit() and few other
functions in vrf, ax25 and bpf.
There are few other cases where this helper can be used
but it requires an additional investigations.
v3 changes:
- ax25 compilation warning fixed
- v5.14-rc4 rebase
- now it does not depend on non-committed pathces
v2 changes:
- helper's name was changed to skb_expand_head
- fixed few mistakes inside skb_expand_head():
skb_set_owner_w should set sk on nskb
kfree was replaced by kfree_skb()
improved warning message
- added minor refactoring in changed functions in vrf and bpf patches
- removed kfree_skb() in ax25_rt_build_path caller ax25_ip_xmit
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
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