From dd04e43d46ad7a4e625a9ff3b270dc0db9abe81d Mon Sep 17 00:00:00 2001 From: Mike Marciniszyn Date: Mon, 10 Jan 2011 17:42:22 -0800 Subject: [PATCH] IB/qib: Unnecessary delayed completions on RC connection Currently on receipt of a response message (ACKs, RDMA Response, Atomic Responses etc.) if the SDMA completion counter is not advanced the driver delays the completion of the WQE. In most cases this is overly pessimistic as the response (ACK) to a previously transmitted send implies that the send is complete. Ensure that SDMA queue is progressed appropriately before determining if a send has delayed completions. Signed-off-by: Mike Marciniszyn Signed-off-by: Roland Dreier --- drivers/infiniband/hw/qib/qib_rc.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/drivers/infiniband/hw/qib/qib_rc.c b/drivers/infiniband/hw/qib/qib_rc.c index 955fb715779..8245237b67c 100644 --- a/drivers/infiniband/hw/qib/qib_rc.c +++ b/drivers/infiniband/hw/qib/qib_rc.c @@ -1407,6 +1407,7 @@ static void qib_rc_rcv_resp(struct qib_ibport *ibp, struct qib_ctxtdata *rcd) { struct qib_swqe *wqe; + struct qib_pportdata *ppd = ppd_from_ibp(ibp); enum ib_wc_status status; unsigned long flags; int diff; @@ -1414,6 +1415,29 @@ static void qib_rc_rcv_resp(struct qib_ibport *ibp, u32 aeth; u64 val; + if (opcode != OP(RDMA_READ_RESPONSE_MIDDLE)) { + /* + * If ACK'd PSN on SDMA busy list try to make progress to + * reclaim SDMA credits. + */ + if ((qib_cmp24(psn, qp->s_sending_psn) >= 0) && + (qib_cmp24(qp->s_sending_psn, qp->s_sending_hpsn) <= 0)) { + + /* + * If send tasklet not running attempt to progress + * SDMA queue. + */ + if (!(qp->s_flags & QIB_S_BUSY)) { + /* Acquire SDMA Lock */ + spin_lock_irqsave(&ppd->sdma_lock, flags); + /* Invoke sdma make progress */ + qib_sdma_make_progress(ppd); + /* Release SDMA Lock */ + spin_unlock_irqrestore(&ppd->sdma_lock, flags); + } + } + } + spin_lock_irqsave(&qp->s_lock, flags); /* Ignore invalid responses. */