• Chuck Lever's avatar
    xprtrdma: Use new CQ API for RPC-over-RDMA client send CQs · 2fa8f88d
    Chuck Lever authored
    Calling ib_poll_cq() to sort through WCs during a completion is a
    common pattern amongst RDMA consumers. Since commit 14d3a3b2
    ("IB: add a proper completion queue abstraction"), WC sorting can
    be handled by the IB core.
    
    By converting to this new API, xprtrdma is made a better neighbor to
    other RDMA consumers, as it allows the core to schedule the delivery
    of completions more fairly amongst all active consumers.
    
    Because each ib_cqe carries a pointer to a completion method, the
    core can now post its own operations on a consumer's QP, and handle
    the completions itself, without changes to the consumer.
    
    Send completions were previously handled entirely in the completion
    upcall handler (ie, deferring to a process context is unneeded).
    Thus IB_POLL_SOFTIRQ is a direct replacement for the current
    xprtrdma send code path.
    Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
    Reviewed-by: default avatarDevesh Sharma <devesh.sharma@broadcom.com>
    Reviewed-by: default avatarSagi Grimberg <sagig@mellanox.com>
    Signed-off-by: default avatarAnna Schumaker <Anna.Schumaker@Netapp.com>
    2fa8f88d
xprt_rdma.h 17 KB