diff options
Diffstat (limited to 'drivers/infiniband/hw/cxgb4/qp.c')
-rw-r--r-- | drivers/infiniband/hw/cxgb4/qp.c | 51 |
1 files changed, 50 insertions, 1 deletions
diff --git a/drivers/infiniband/hw/cxgb4/qp.c b/drivers/infiniband/hw/cxgb4/qp.c index 5f940ae..beec667 100644 --- a/drivers/infiniband/hw/cxgb4/qp.c +++ b/drivers/infiniband/hw/cxgb4/qp.c @@ -34,6 +34,10 @@ #include "iw_cxgb4.h" +static int db_delay_usecs = 1; +module_param(db_delay_usecs, int, 0644); +MODULE_PARM_DESC(db_delay_usecs, "Usecs to delay awaiting db fifo to drain"); + static int ocqp_support = 1; module_param(ocqp_support, int, 0644); MODULE_PARM_DESC(ocqp_support, "Support on-chip SQs (default=1)"); @@ -1128,6 +1132,29 @@ out: return ret; } +/* + * Called by the library when the qp has user dbs disabled due to + * a DB_FULL condition. This function will single-thread all user + * DB rings to avoid overflowing the hw db-fifo. + */ +static int ring_kernel_db(struct c4iw_qp *qhp, u32 qid, u16 inc) +{ + int delay = db_delay_usecs; + + mutex_lock(&qhp->rhp->db_mutex); + do { + if (cxgb4_dbfifo_count(qhp->rhp->rdev.lldi.ports[0], 1) < 768) { + writel(V_QID(qid) | V_PIDX(inc), qhp->wq.db); + break; + } + set_current_state(TASK_UNINTERRUPTIBLE); + schedule_timeout(usecs_to_jiffies(delay)); + delay = min(delay << 1, 200000); + } while (1); + mutex_unlock(&qhp->rhp->db_mutex); + return 0; +} + int c4iw_modify_qp(struct c4iw_dev *rhp, struct c4iw_qp *qhp, enum c4iw_qp_attr_mask mask, struct c4iw_qp_attributes *attrs, @@ -1176,6 +1203,15 @@ int c4iw_modify_qp(struct c4iw_dev *rhp, struct c4iw_qp *qhp, qhp->attr = newattr; } + if (mask & C4IW_QP_ATTR_SQ_DB) { + ret = ring_kernel_db(qhp, qhp->wq.sq.qid, attrs->sq_db_inc); + goto out; + } + if (mask & C4IW_QP_ATTR_RQ_DB) { + ret = ring_kernel_db(qhp, qhp->wq.rq.qid, attrs->rq_db_inc); + goto out; + } + if (!(mask & C4IW_QP_ATTR_NEXT_STATE)) goto out; if (qhp->attr.state == attrs->next_state) @@ -1469,7 +1505,11 @@ struct ib_qp *c4iw_create_qp(struct ib_pd *pd, struct ib_qp_init_attr *attrs, init_waitqueue_head(&qhp->wait); atomic_set(&qhp->refcnt, 1); - ret = insert_handle(rhp, &rhp->qpidr, qhp, qhp->wq.sq.qid); + spin_lock_irq(&rhp->lock); + if (rhp->db_state != NORMAL) + t4_disable_wq_db(&qhp->wq); + ret = insert_handle_nolock(rhp, &rhp->qpidr, qhp, qhp->wq.sq.qid); + spin_unlock_irq(&rhp->lock); if (ret) goto err2; @@ -1613,6 +1653,15 @@ int c4iw_ib_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr, C4IW_QP_ATTR_ENABLE_RDMA_WRITE | C4IW_QP_ATTR_ENABLE_RDMA_BIND) : 0; + /* + * Use SQ_PSN and RQ_PSN to pass in IDX_INC values for + * ringing the queue db when we're in DB_FULL mode. + */ + attrs.sq_db_inc = attr->sq_psn; + attrs.rq_db_inc = attr->rq_psn; + mask |= (attr_mask & IB_QP_SQ_PSN) ? C4IW_QP_ATTR_SQ_DB : 0; + mask |= (attr_mask & IB_QP_RQ_PSN) ? C4IW_QP_ATTR_RQ_DB : 0; + return c4iw_modify_qp(rhp, qhp, mask, &attrs, 0); } |