• Jon Paul Maloy's avatar
    tipc: reduce locking scope during packet reception · d999297c
    Jon Paul Maloy authored
    We convert packet/message reception according to the same principle
    we have been using for message sending and timeout handling:
    
    We move the function tipc_rcv() to node.c, hence handling the initial
    packet reception at the link aggregation level. The function grabs
    the node lock, selects the receiving link, and accesses it via a new
    call tipc_link_rcv(). This function appends buffers to the input
    queue for delivery upwards, but it may also append outgoing packets
    to the xmit queue, just as we do during regular message sending. The
    latter will happen when buffers are forwarded from the link backlog,
    or when retransmission is requested.
    
    Upon return of this function, and after having released the node lock,
    tipc_rcv() delivers/tranmsits the contents of those queues, but it may
    also perform actions such as link activation or reset, as indicated by
    the return flags from the link.
    
    This reduces the number of cpu cycles spent inside the node spinlock,
    and reduces contention on that lock.
    Reviewed-by: default avatarYing Xue <ying.xue@windriver.com>
    Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    d999297c
node.c 24.8 KB