• Joe Stringer's avatar
    openvswitch: Add support for unique flow IDs. · 74ed7ab9
    Joe Stringer authored
    Previously, flows were manipulated by userspace specifying a full,
    unmasked flow key. This adds significant burden onto flow
    serialization/deserialization, particularly when dumping flows.
    
    This patch adds an alternative way to refer to flows using a
    variable-length "unique flow identifier" (UFID). At flow setup time,
    userspace may specify a UFID for a flow, which is stored with the flow
    and inserted into a separate table for lookup, in addition to the
    standard flow table. Flows created using a UFID must be fetched or
    deleted using the UFID.
    
    All flow dump operations may now be made more terse with OVS_UFID_F_*
    flags. For example, the OVS_UFID_F_OMIT_KEY flag allows responses to
    omit the flow key from a datapath operation if the flow has a
    corresponding UFID. This significantly reduces the time spent assembling
    and transacting netlink messages. With all OVS_UFID_F_OMIT_* flags
    enabled, the datapath only returns the UFID and statistics for each flow
    during flow dump, increasing ovs-vswitchd revalidator performance by 40%
    or more.
    Signed-off-by: 's avatarJoe Stringer <joestringer@nicira.com>
    Acked-by: 's avatarPravin B Shelar <pshelar@nicira.com>
    Signed-off-by: 's avatarDavid S. Miller <davem@davemloft.net>
    74ed7ab9