• Patrick Ohly's avatar
    net: new user space API for time stamping of incoming and outgoing packets · cb9eff09
    Patrick Ohly authored
    User space can request hardware and/or software time stamping.
    Reporting of the result(s) via a new control message is enabled
    separately for each field in the message because some of the
    fields may require additional computation and thus cause overhead.
    User space can tell the different kinds of time stamps apart
    and choose what suits its needs.
    
    When a TX timestamp operation is requested, the TX skb will be cloned
    and the clone will be time stamped (in hardware or software) and added
    to the socket error queue of the skb, if the skb has a socket
    associated with it.
    
    The actual TX timestamp will reach userspace as a RX timestamp on the
    cloned packet. If timestamping is requested and no timestamping is
    done in the device driver (potentially this may use hardware
    timestamping), it will be done in software after the device's
    start_hard_xmit routine.
    Signed-off-by: default avatarPatrick Ohly <patrick.ohly@intel.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    cb9eff09
socket.h 1.37 KB