iw_cxgb4: Atomically flush per QP HW CQEs
When a CQ is shared by multiple QPs, c4iw_flush_hw_cq() needs to acquire
corresponding QP lock before moving the CQEs into its corresponding SW
queue and accessing the SQ contents for completing a WR.
Ignore CQEs if corresponding QP is already flushed.
Cc: stable@vger.kernel.org
Signed-off-by: Potnuri Bharat Teja <bharat@chelsio.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/infiniband/hw/cxgb4/cq.c b/drivers/infiniband/hw/cxgb4/cq.c
index 6f2b261..2be2e1a 100644
--- a/drivers/infiniband/hw/cxgb4/cq.c
+++ b/drivers/infiniband/hw/cxgb4/cq.c
@@ -315,7 +315,7 @@ static void advance_oldest_read(struct t4_wq *wq)
* Deal with out-of-order and/or completions that complete
* prior unsignalled WRs.
*/
-void c4iw_flush_hw_cq(struct c4iw_cq *chp)
+void c4iw_flush_hw_cq(struct c4iw_cq *chp, struct c4iw_qp *flush_qhp)
{
struct t4_cqe *hw_cqe, *swcqe, read_cqe;
struct c4iw_qp *qhp;
@@ -339,6 +339,13 @@ void c4iw_flush_hw_cq(struct c4iw_cq *chp)
if (qhp == NULL)
goto next_cqe;
+ if (flush_qhp != qhp) {
+ spin_lock(&qhp->lock);
+
+ if (qhp->wq.flushed == 1)
+ goto next_cqe;
+ }
+
if (CQE_OPCODE(hw_cqe) == FW_RI_TERMINATE)
goto next_cqe;
@@ -390,6 +397,8 @@ void c4iw_flush_hw_cq(struct c4iw_cq *chp)
next_cqe:
t4_hwcq_consume(&chp->cq);
ret = t4_next_hw_cqe(&chp->cq, &hw_cqe);
+ if (qhp && flush_qhp != qhp)
+ spin_unlock(&qhp->lock);
}
}