IB/hfi1: Remove dependence on qp->s_hdrwords

The s_hdrwords variable was used to indicate whether a
packet was already built on a previous iteration of the
send engine. This variable assumed the protection of the
QP's RVT_S_BUSY flag, which was required since the the
QP's s_lock was dropped just prior to the packet being
queued on the one of the egress mechanisms.

Support for multiple send engine instantiations require
that the field not be used due to concurency issues.
The ps.txreq signals the "already built" without the
potential concurency issues.

Fix by getting rid of all s_hdrword usage.   A wrapper
is added to test for the already built case that used to
use s_hdrwords.

What used to be stored in s_hdrwords is now in the txreq.
The PBC is not counted, but is added in the pio/sdma code
paths prior to posting the packet.

Reviewed-by: Don Hiatt <don.hiatt@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/hfi1/verbs_txreq.h b/drivers/infiniband/hw/hfi1/verbs_txreq.h
index cec7a4b34d16..729244c3086c 100644
--- a/drivers/infiniband/hw/hfi1/verbs_txreq.h
+++ b/drivers/infiniband/hw/hfi1/verbs_txreq.h
@@ -113,6 +113,13 @@ static inline struct verbs_txreq *get_waiting_verbs_txreq(struct rvt_qp *qp)
 	return NULL;
 }
 
+static inline bool verbs_txreq_queued(struct rvt_qp *qp)
+{
+	struct hfi1_qp_priv *priv = qp->priv;
+
+	return iowait_packet_queued(&priv->s_iowait);
+}
+
 void hfi1_put_txreq(struct verbs_txreq *tx);
 int verbs_txreq_init(struct hfi1_ibdev *dev);
 void verbs_txreq_exit(struct hfi1_ibdev *dev);