RDMA/cxgb3: QP flush fixes
- Flush the QP only after the HW disables the connection. Currently
we flush the QP when transitioning to CLOSING. This exposes a race
condition where the HW can complete a RECV WR, for instance, -and-
the SW can flush that same WR.
- Only call CQ event handlers on flush IFF we actually flushed something.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/hw/cxgb3/iwch_qp.c b/drivers/infiniband/hw/cxgb3/iwch_qp.c
index 9b4be88..79dbe5b 100644
--- a/drivers/infiniband/hw/cxgb3/iwch_qp.c
+++ b/drivers/infiniband/hw/cxgb3/iwch_qp.c
@@ -655,6 +655,7 @@
{
struct iwch_cq *rchp, *schp;
int count;
+ int flushed;
rchp = get_chp(qhp->rhp, qhp->attr.rcq);
schp = get_chp(qhp->rhp, qhp->attr.scq);
@@ -669,20 +670,22 @@
spin_lock(&qhp->lock);
cxio_flush_hw_cq(&rchp->cq);
cxio_count_rcqes(&rchp->cq, &qhp->wq, &count);
- cxio_flush_rq(&qhp->wq, &rchp->cq, count);
+ flushed = cxio_flush_rq(&qhp->wq, &rchp->cq, count);
spin_unlock(&qhp->lock);
spin_unlock_irqrestore(&rchp->lock, *flag);
- (*rchp->ibcq.comp_handler)(&rchp->ibcq, rchp->ibcq.cq_context);
+ if (flushed)
+ (*rchp->ibcq.comp_handler)(&rchp->ibcq, rchp->ibcq.cq_context);
/* locking heirarchy: cq lock first, then qp lock. */
spin_lock_irqsave(&schp->lock, *flag);
spin_lock(&qhp->lock);
cxio_flush_hw_cq(&schp->cq);
cxio_count_scqes(&schp->cq, &qhp->wq, &count);
- cxio_flush_sq(&qhp->wq, &schp->cq, count);
+ flushed = cxio_flush_sq(&qhp->wq, &schp->cq, count);
spin_unlock(&qhp->lock);
spin_unlock_irqrestore(&schp->lock, *flag);
- (*schp->ibcq.comp_handler)(&schp->ibcq, schp->ibcq.cq_context);
+ if (flushed)
+ (*schp->ibcq.comp_handler)(&schp->ibcq, schp->ibcq.cq_context);
/* deref */
if (atomic_dec_and_test(&qhp->refcnt))
@@ -880,7 +883,6 @@
ep = qhp->ep;
get_ep(&ep->com);
}
- flush_qp(qhp, &flag);
break;
case IWCH_QP_STATE_TERMINATE:
qhp->attr.state = IWCH_QP_STATE_TERMINATE;
@@ -911,6 +913,7 @@
}
switch (attrs->next_state) {
case IWCH_QP_STATE_IDLE:
+ flush_qp(qhp, &flag);
qhp->attr.state = IWCH_QP_STATE_IDLE;
qhp->attr.llp_stream_handle = NULL;
put_ep(&qhp->ep->com);