• Eyal Birger's avatar
    net: move skb->dropcount to skb->cb[] · 744d5a3e
    Eyal Birger authored
    Commit 97775007 ("af_packet: add interframe drop cmsg (v6)")
    unionized skb->mark and skb->dropcount in order to allow recording
    of the socket drop count while maintaining struct sk_buff size.
    
    skb->dropcount was introduced since there was no available room
    in skb->cb[] in packet sockets. However, its introduction led to
    the inability to export skb->mark, or any other aliased field to
    userspace if so desired.
    
    Moving the dropcount metric to skb->cb[] eliminates this problem
    at the expense of 4 bytes less in skb->cb[] for protocol families
    using it.
    Signed-off-by: default avatarEyal Birger <eyal.birger@gmail.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    744d5a3e
socket.c 81.7 KB