IB/qib: Decode path MTU optimization

Store both the encoded and decoded MTU in the QP structure as a minor
optimization for UC/RC receive routines.

Signed-off-by: Mike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

diff --git a/drivers/infiniband/hw/qib/qib_qp.c b/drivers/infiniband/hw/qib/qib_qp.c
index e16751f..9d094f9 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_qp.c
+++ b/drivers/infiniband/hw/qib/qib_qp.c
@@ -765,8 +765,10 @@ int qib_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
                }
        }
 
-       if (attr_mask & IB_QP_PATH_MTU)
+       if (attr_mask & IB_QP_PATH_MTU) {
                qp->path_mtu = pmtu;
+               qp->pmtu = ib_mtu_enum_to_int(pmtu);
+       }
 
        if (attr_mask & IB_QP_RETRY_CNT) {
                qp->s_retry_cnt = attr->retry_cnt;

diff --git a/drivers/infiniband/hw/qib/qib_rc.c b/drivers/infiniband/hw/qib/qib_rc.c
index 5c1c49b..5d77cb8 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_rc.c
+++ b/drivers/infiniband/hw/qib/qib_rc.c
@@ -239,7 +239,7 @@ int qib_make_rc_req(struct qib_qp *qp)
        u32 len;
        u32 bth0;
        u32 bth2;
-       u32 pmtu = ib_mtu_enum_to_int(qp->path_mtu);
+       u32 pmtu = qp->pmtu;
        char newreq;
        unsigned long flags;
        int ret = 0;
@@ -1732,7 +1732,7 @@ static int qib_rc_rcv_error(struct qib_other_headers *ohdr,
                 * same request.
                 */
                offset = ((psn - e->psn) & QIB_PSN_MASK) *
-                       ib_mtu_enum_to_int(qp->path_mtu);
+                       qp->pmtu;
                len = be32_to_cpu(reth->length);
                if (unlikely(offset + len != e->rdma_sge.sge_length))
                        goto unlock_done;
@@ -1876,7 +1876,7 @@ void qib_rc_rcv(struct qib_ctxtdata *rcd, struct qib_ib_header *hdr,
        u32 psn;
        u32 pad;
        struct ib_wc wc;
-       u32 pmtu = ib_mtu_enum_to_int(qp->path_mtu);
+       u32 pmtu = qp->pmtu;
        int diff;
        struct ib_reth *reth;
        unsigned long flags;

diff --git a/drivers/infiniband/hw/qib/qib_uc.c b/drivers/infiniband/hw/qib/qib_uc.c
index d31f33a..9a4630f 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_uc.c
+++ b/drivers/infiniband/hw/qib/qib_uc.c
@@ -51,7 +51,7 @@ int qib_make_uc_req(struct qib_qp *qp)
        u32 hwords;
        u32 bth0;
        u32 len;
-       u32 pmtu = ib_mtu_enum_to_int(qp->path_mtu);
+       u32 pmtu = qp->pmtu;
        int ret = 0;
 
        spin_lock_irqsave(&qp->s_lock, flags);
@@ -249,7 +249,7 @@ void qib_uc_rcv(struct qib_ibport *ibp, struct qib_ib_header *hdr,
        u32 psn;
        u32 pad;
        struct ib_wc wc;
-       u32 pmtu = ib_mtu_enum_to_int(qp->path_mtu);
+       u32 pmtu = qp->pmtu;
        struct ib_reth *reth;
        int ret;
 

diff --git a/drivers/infiniband/hw/qib/qib_verbs.h b/drivers/infiniband/hw/qib/qib_verbs.h
index 95e5b47..ec3711f 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_verbs.h
+++ b/drivers/infiniband/hw/qib/qib_verbs.h
@@ -485,6 +485,7 @@ struct qib_qp {
        u8 alt_timeout;         /* Alternate path timeout for this QP */
        u8 port_num;
        enum ib_mtu path_mtu;
+       u32 pmtu;               /* decoded from path_mtu */
        u32 remote_qpn;
        u32 qkey;               /* QKEY for this QP (for UD or RD) */
        u32 s_size;             /* send work queue size */