IB/qib, staging/rdma/hfi1: add s_hlock for use in post send

[karo-tx-linux.git] / drivers / staging / rdma / hfi1 / ruc.c

diff --git a/drivers/staging/rdma/hfi1/ruc.c b/drivers/staging/rdma/hfi1/ruc.c
index a7add3c5d0f2b0a1ccb9b09f460b5d61582459b5..6114550bb73f3f92201b55bdb57437dccbc33ff5 100644 (file)
--- a/drivers/staging/rdma/hfi1/ruc.c
+++ b/drivers/staging/rdma/hfi1/ruc.c
@@ -392,7 +392,8 @@ static void ruc_loopback(struct rvt_qp *sqp)
        sqp->s_flags |= RVT_S_BUSY;
 
 again:
-       if (sqp->s_last == sqp->s_head)
+       smp_read_barrier_depends(); /* see post_one_send() */
+       if (sqp->s_last == ACCESS_ONCE(sqp->s_head))
                goto clr_busy;
        wqe = rvt_get_swqe_ptr(sqp, sqp->s_last);
 
@@ -871,40 +872,43 @@ void hfi1_do_send(struct rvt_qp *qp)
 
        qp->s_flags |= RVT_S_BUSY;
 
-       spin_unlock_irqrestore(&qp->s_lock, flags);
-
        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) {
+                       spin_unlock_irqrestore(&qp->s_lock, flags);
                        /*
                         * If the packet cannot be sent now, return and
                         * the send tasklet will be woken up later.
                         */
                        if (hfi1_verbs_send(qp, &ps))
-                               break;
+                               return;
                        /* Record that s_hdr is empty. */
                        qp->s_hdrwords = 0;
-               }
-
-               /* 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);
+                       /* 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);
-                               return;
+                               timeout = jiffies + (timeout_int) / 8;
                        }
-                       cond_resched();
-                       this_cpu_inc(*ps.ppd->dd->send_schedule);
-                       timeout = jiffies + (timeout_int) / 8;
+                       spin_lock_irqsave(&qp->s_lock, flags);
                }
        } while (make_req(qp));
+
+       spin_unlock_irqrestore(&qp->s_lock, flags);
 }
 
 /*