• Johannes Berg's avatar
    mac80211: add fast-rx path · 49ddf8e6
    Johannes Berg authored
    The regular RX path has a lot of code, but with a few
    assumptions on the hardware it's possible to reduce the
    amount of code significantly. Currently the assumptions
    on the driver are the following:
     * hardware/driver reordering buffer (if supporting aggregation)
     * hardware/driver decryption & PN checking (if using encryption)
     * hardware/driver did de-duplication
     * hardware/driver did A-MSDU deaggregation
     * AP_LINK_PS is used (in AP mode)
     * no client powersave handling in mac80211 (in client mode)
    of which some are actually checked per packet:
     * de-duplication
     * PN checking
     * decryption
    and additionally packets must
     * not be A-MSDU (have been deaggregated by driver/device)
     * be data packets
     * not be fragmented
     * be unicast
     * have RFC 1042 header
    Additionally dynamically we assume:
     * no encryption or CCMP/GCMP, TKIP/WEP/other not allowed
     * station must be authorized
     * 4-addr format not enabled
    Some data needed for the RX path is cached in a new per-station
    "fast_rx" structure, so that we only need to look at this and
    the packet, no other memory when processing packets on the fast
    RX path.
    After doing the above per-packet checks, the data path collapses
    down to a pretty simple conversion function taking advantage of
    the data cached in the small fast_rx struct.
    This should speed up the RX processing, and will make it easier
    to reason about parallelizing RX (for which statistics will need
    to be per-CPU still.)
    Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
mlme.c 143 KB