help me to know when ethernet header added to packet by eth_header function

help me to know when ethernet header added to packet by eth_header function

[linux lover]

Hello,
      Can anybody explain me how ethernet header is
added to every packet outgoing? I check eth.c file and
found eth_header that is used for adding ethernet
header on skbuff packet. But does each packet calls
this function? I think not as theres a cache header
function used that cache ethernet header entry.
      So my main question is that when my machine
first contacted to any other pc in LAN does it calls
eth_header and when require to send any type of packet
to same machine i thnik eth_cache_header is used is
that right???
      Then can it be possible that if my machine not
contacted to any cached entry machine then eth_header
will be called again to build eth header for that
machine?
      In an all when functions in eth.c will be
called/not called
eth_header,eth_header_cache,eth_header_parse,eth_header_cache_update???
      Please kindly help me to identify it.
Thanks in advance.
regards,
linux_lover.


	
		
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