IB/{rdmavt, hfi1, qib}: Add a counter for credit waits

This patch adds a counter for credit waits to assist field debugging.

Link: https://lore.kernel.org/r/20190911113047.126040.10857.stgit@awfm-01.aw.intel.com
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@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>

diff --git a/drivers/infiniband/hw/hfi1/chip.c b/drivers/infiniband/hw/hfi1/chip.c
index 67052dc..9b1fb84 100644 (file)
--- a/drivers/infiniband/hw/hfi1/chip.c
+++ b/drivers/infiniband/hw/hfi1/chip.c
@@ -4101,6 +4101,7 @@ def_access_ibp_counter(rc_dupreq);
 def_access_ibp_counter(rdma_seq);
 def_access_ibp_counter(unaligned);
 def_access_ibp_counter(seq_naks);
+def_access_ibp_counter(rc_crwaits);
 
 static struct cntr_entry dev_cntrs[DEV_CNTR_LAST] = {
 [C_RCV_OVF] = RXE32_DEV_CNTR_ELEM(RcvOverflow, RCV_BUF_OVFL_CNT, CNTR_SYNTH),
@@ -5119,6 +5120,7 @@ static struct cntr_entry port_cntrs[PORT_CNTR_LAST] = {
 [C_SW_IBP_RDMA_SEQ] = SW_IBP_CNTR(RdmaSeq, rdma_seq),
 [C_SW_IBP_UNALIGNED] = SW_IBP_CNTR(Unaligned, unaligned),
 [C_SW_IBP_SEQ_NAK] = SW_IBP_CNTR(SeqNak, seq_naks),
+[C_SW_IBP_RC_CRWAITS] = SW_IBP_CNTR(RcCrWait, rc_crwaits),
 [C_SW_CPU_RC_ACKS] = CNTR_ELEM("RcAcks", 0, 0, CNTR_NORMAL,
                               access_sw_cpu_rc_acks),
 [C_SW_CPU_RC_QACKS] = CNTR_ELEM("RcQacks", 0, 0, CNTR_NORMAL,

diff --git a/drivers/infiniband/hw/hfi1/chip.h b/drivers/infiniband/hw/hfi1/chip.h
index b76cf81..4ca5ac8 100644 (file)
--- a/drivers/infiniband/hw/hfi1/chip.h
+++ b/drivers/infiniband/hw/hfi1/chip.h
@@ -1245,6 +1245,7 @@ enum {
        C_SW_IBP_RDMA_SEQ,
        C_SW_IBP_UNALIGNED,
        C_SW_IBP_SEQ_NAK,
+       C_SW_IBP_RC_CRWAITS,
        C_SW_CPU_RC_ACKS,
        C_SW_CPU_RC_QACKS,
        C_SW_CPU_RC_DELAYED_COMP,

diff --git a/drivers/infiniband/hw/hfi1/rc.c b/drivers/infiniband/hw/hfi1/rc.c
index eeca08d..513a8aa 100644 (file)
--- a/drivers/infiniband/hw/hfi1/rc.c
+++ b/drivers/infiniband/hw/hfi1/rc.c
@@ -595,11 +595,8 @@ check_s_state:
                case IB_WR_SEND_WITH_IMM:
                case IB_WR_SEND_WITH_INV:
                        /* If no credit, return. */
-                       if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT) &&
-                           rvt_cmp_msn(wqe->ssn, qp->s_lsn + 1) > 0) {
-                               qp->s_flags |= RVT_S_WAIT_SSN_CREDIT;
+                       if (!rvt_rc_credit_avail(qp, wqe))
                                goto bail;
-                       }
                        if (len > pmtu) {
                                qp->s_state = OP(SEND_FIRST);
                                len = pmtu;
@@ -632,11 +629,8 @@ check_s_state:
                        goto no_flow_control;
                case IB_WR_RDMA_WRITE_WITH_IMM:
                        /* If no credit, return. */
-                       if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT) &&
-                           rvt_cmp_msn(wqe->ssn, qp->s_lsn + 1) > 0) {
-                               qp->s_flags |= RVT_S_WAIT_SSN_CREDIT;
+                       if (!rvt_rc_credit_avail(qp, wqe))
                                goto bail;
-                       }
 no_flow_control:
                        put_ib_reth_vaddr(
                                wqe->rdma_wr.remote_addr,

diff --git a/drivers/infiniband/hw/qib/qib_rc.c b/drivers/infiniband/hw/qib/qib_rc.c
index 1d5e2d4..aaf7438 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_rc.c
+++ b/drivers/infiniband/hw/qib/qib_rc.c
@@ -313,11 +313,8 @@ int qib_make_rc_req(struct rvt_qp *qp, unsigned long *flags)
                case IB_WR_SEND:
                case IB_WR_SEND_WITH_IMM:
                        /* If no credit, return. */
-                       if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT) &&
-                           rvt_cmp_msn(wqe->ssn, qp->s_lsn + 1) > 0) {
-                               qp->s_flags |= RVT_S_WAIT_SSN_CREDIT;
+                       if (!rvt_rc_credit_avail(qp, wqe))
                                goto bail;
-                       }
                        if (len > pmtu) {
                                qp->s_state = OP(SEND_FIRST);
                                len = pmtu;
@@ -344,11 +341,8 @@ int qib_make_rc_req(struct rvt_qp *qp, unsigned long *flags)
                        goto no_flow_control;
                case IB_WR_RDMA_WRITE_WITH_IMM:
                        /* If no credit, return. */
-                       if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT) &&
-                           rvt_cmp_msn(wqe->ssn, qp->s_lsn + 1) > 0) {
-                               qp->s_flags |= RVT_S_WAIT_SSN_CREDIT;
+                       if (!rvt_rc_credit_avail(qp, wqe))
                                goto bail;
-                       }
 no_flow_control:
                        ohdr->u.rc.reth.vaddr =
                                cpu_to_be64(wqe->rdma_wr.remote_addr);

diff --git a/drivers/infiniband/hw/qib/qib_sysfs.c b/drivers/infiniband/hw/qib/qib_sysfs.c
index 905206a..3926be7 100644 (file)
--- a/drivers/infiniband/hw/qib/qib_sysfs.c
+++ b/drivers/infiniband/hw/qib/qib_sysfs.c
@@ -436,6 +436,7 @@ QIB_DIAGC_ATTR(dmawait);
 QIB_DIAGC_ATTR(unaligned);
 QIB_DIAGC_ATTR(rc_dupreq);
 QIB_DIAGC_ATTR(rc_seqnak);
+QIB_DIAGC_ATTR(rc_crwaits);
 
 static struct attribute *diagc_default_attributes[] = {
        &qib_diagc_attr_rc_resends.attr,
@@ -453,6 +454,7 @@ static struct attribute *diagc_default_attributes[] = {
        &qib_diagc_attr_unaligned.attr,
        &qib_diagc_attr_rc_dupreq.attr,
        &qib_diagc_attr_rc_seqnak.attr,
+       &qib_diagc_attr_rc_crwaits.attr,
        NULL
 };
 

diff --git a/include/rdma/rdma_vt.h b/include/rdma/rdma_vt.h
index 525848e..ac5a943 100644 (file)
--- a/include/rdma/rdma_vt.h
+++ b/include/rdma/rdma_vt.h
@@ -116,6 +116,7 @@ struct rvt_ibport {
        u64 n_unaligned;
        u64 n_rc_dupreq;
        u64 n_rc_seqnak;
+       u64 n_rc_crwaits;
        u16 pkey_violations;
        u16 qkey_violations;
        u16 mkey_violations;

diff --git a/include/rdma/rdmavt_qp.h b/include/rdma/rdmavt_qp.h
index e06c77d..b550ae8 100644 (file)
--- a/include/rdma/rdmavt_qp.h
+++ b/include/rdma/rdmavt_qp.h
@@ -973,6 +973,41 @@ static inline void rvt_free_rq(struct rvt_rq *rq)
        rq->wq = NULL;
 }
 
+/**
+ * rvt_to_iport - Get the ibport pointer
+ * @qp: the qp pointer
+ *
+ * This function returns the ibport pointer from the qp pointer.
+ */
+static inline struct rvt_ibport *rvt_to_iport(struct rvt_qp *qp)
+{
+       struct rvt_dev_info *rdi = ib_to_rvt(qp->ibqp.device);
+
+       return rdi->ports[qp->port_num - 1];
+}
+
+/**
+ * rvt_rc_credit_avail - Check if there are enough RC credits for the request
+ * @qp: the qp
+ * @wqe: the request
+ *
+ * This function returns false when there are not enough credits for the given
+ * request and true otherwise.
+ */
+static inline bool rvt_rc_credit_avail(struct rvt_qp *qp, struct rvt_swqe *wqe)
+{
+       lockdep_assert_held(&qp->s_lock);
+       if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT) &&
+           rvt_cmp_msn(wqe->ssn, qp->s_lsn + 1) > 0) {
+               struct rvt_ibport *rvp = rvt_to_iport(qp);
+
+               qp->s_flags |= RVT_S_WAIT_SSN_CREDIT;
+               rvp->n_rc_crwaits++;
+               return false;
+       }
+       return true;
+}
+
 struct rvt_qp_iter *rvt_qp_iter_init(struct rvt_dev_info *rdi,
                                     u64 v,
                                     void (*cb)(struct rvt_qp *qp, u64 v));