From 23cd4716b7e2792f1fdc31b83feb9e9a9812c25f Mon Sep 17 00:00:00 2001 From: Vennila Megavannan Date: Wed, 3 Feb 2016 14:34:23 -0800 Subject: [PATCH] staging/rdma/hfi1: Allow a fair scheduling of QPs This patch fixes the fairness issues in QP scheduling - the timeout for cond_resched is changed to a ratio of qp->timeout_jiffies - workqueue_congested is used to determine if qp needs to reschedule itself Reviewed-by: Mike Marciniszyn Signed-off-by: Vennila Megavannan Signed-off-by: Jubin John Signed-off-by: Doug Ledford --- drivers/staging/rdma/hfi1/ruc.c | 52 ++++++++++++++++++++++++--------- 1 file changed, 38 insertions(+), 14 deletions(-) diff --git a/drivers/staging/rdma/hfi1/ruc.c b/drivers/staging/rdma/hfi1/ruc.c index ae28b85b8475..f09badbfa51c 100644 --- a/drivers/staging/rdma/hfi1/ruc.c +++ b/drivers/staging/rdma/hfi1/ruc.c @@ -822,29 +822,42 @@ void _hfi1_do_send(struct work_struct *work) void hfi1_do_send(struct rvt_qp *qp) { struct hfi1_pkt_state ps; + struct hfi1_qp_priv *priv = qp->priv; int (*make_req)(struct rvt_qp *qp); unsigned long flags; unsigned long timeout; + unsigned long timeout_int; + int cpu; ps.dev = to_idev(qp->ibqp.device); ps.ibp = to_iport(qp->ibqp.device, qp->port_num); ps.ppd = ppd_from_ibp(ps.ibp); - if ((qp->ibqp.qp_type == IB_QPT_RC || - qp->ibqp.qp_type == IB_QPT_UC) && - !loopback && - (qp->remote_ah_attr.dlid & ~((1 << ps.ppd->lmc) - 1)) == - ps.ppd->lid) { - ruc_loopback(qp); - return; - } - - if (qp->ibqp.qp_type == IB_QPT_RC) + switch (qp->ibqp.qp_type) { + case IB_QPT_RC: + if (!loopback && ((qp->remote_ah_attr.dlid & ~((1 << ps.ppd->lmc + ) - 1)) == + ps.ppd->lid)) { + ruc_loopback(qp); + return; + } make_req = hfi1_make_rc_req; - else if (qp->ibqp.qp_type == IB_QPT_UC) + timeout_int = (qp->timeout_jiffies); + break; + case IB_QPT_UC: + if (!loopback && ((qp->remote_ah_attr.dlid & ~((1 << ps.ppd->lmc + ) - 1)) == + ps.ppd->lid)) { + ruc_loopback(qp); + return; + } make_req = hfi1_make_uc_req; - else + timeout_int = SEND_RESCHED_TIMEOUT; + break; + default: make_req = hfi1_make_ud_req; + timeout_int = SEND_RESCHED_TIMEOUT; + } spin_lock_irqsave(&qp->s_lock, flags); @@ -858,7 +871,9 @@ void hfi1_do_send(struct rvt_qp *qp) spin_unlock_irqrestore(&qp->s_lock, flags); - timeout = jiffies + SEND_RESCHED_TIMEOUT; + timeout = jiffies + (timeout_int) / 8; + cpu = priv->s_sde ? priv->s_sde->cpu : + cpumask_first(cpumask_of_node(ps.ppd->dd->node)); do { /* Check for a constructed packet to be sent. */ if (qp->s_hdrwords != 0) { @@ -874,9 +889,18 @@ void hfi1_do_send(struct rvt_qp *qp) /* allow other tasks to run */ if (unlikely(time_after(jiffies, timeout))) { + if (workqueue_congested(cpu, ps.ppd->hfi1_wq)) { + spin_lock_irqsave(&qp->s_lock, flags); + qp->s_flags &= ~RVT_S_BUSY; + hfi1_schedule_send(qp); + spin_unlock_irqrestore(&qp->s_lock, + flags); + this_cpu_inc(*ps.ppd->dd->send_schedule); + return; + } cond_resched(); this_cpu_inc(*ps.ppd->dd->send_schedule); - timeout = jiffies + SEND_RESCHED_TIMEOUT; + timeout = jiffies + (timeout_int) / 8; } } while (make_req(qp)); } -- 2.20.1