Re: [for-next V2 10/10] RDMA/core: Provide RDMA DIM support for ULPs

[Sagi Grimberg]

+static int ib_poll_dim_handler(struct irq_poll *iop, int budget)
+{
+       struct ib_cq *cq = container_of(iop, struct ib_cq, iop);
+       struct dim *dim = cq->dim;
+       int completed;
+
+       completed = __ib_process_cq(cq, budget, cq->wc, IB_POLL_BATCH);
+       if (completed < budget) {
+               irq_poll_complete(&cq->iop);
+               if (ib_req_notify_cq(cq, IB_POLL_FLAGS) > 0)
+                       irq_poll_sched(&cq->iop);
+       }
+
+       rdma_dim(dim, completed);

Why duplicate the entire thing for a one-liner?

+
+       return completed;
+}
+
  static void ib_cq_completion_softirq(struct ib_cq *cq, void *private)
  {
        irq_poll_sched(&cq->iop);
@@ -105,14 +157,18 @@ static void ib_cq_completion_softirq(struct ib_cq *cq, 
void *private)

static void ib_cq_poll_work(struct work_struct *work)

  {
-       struct ib_cq *cq = container_of(work, struct ib_cq, work);
+       struct ib_cq *cq = container_of(work, struct ib_cq,
+                                       work);

Why was that changed?

        int completed;

completed = __ib_process_cq(cq, IB_POLL_BUDGET_WORKQUEUE, cq->wc,

                                    IB_POLL_BATCH);
+

newline?

        if (completed >= IB_POLL_BUDGET_WORKQUEUE ||
            ib_req_notify_cq(cq, IB_POLL_FLAGS) > 0)
                queue_work(cq->comp_wq, &cq->work);
+       else if (cq->dim)
+               rdma_dim(cq->dim, completed);
  }

static void ib_cq_completion_workqueue(struct ib_cq *cq, void *private)

@@ -166,6 +222,8 @@ struct ib_cq *__ib_alloc_cq_user(struct ib_device *dev, 
void *private,
        rdma_restrack_set_task(&cq->res, caller);
        rdma_restrack_kadd(&cq->res);

+ rdma_dim_init(cq);

+
        switch (cq->poll_ctx) {
        case IB_POLL_DIRECT:
                cq->comp_handler = ib_cq_completion_direct;
@@ -173,7 +231,13 @@ struct ib_cq *__ib_alloc_cq_user(struct ib_device *dev, 
void *private,
        case IB_POLL_SOFTIRQ:
                cq->comp_handler = ib_cq_completion_softirq;

- irq_poll_init(&cq->iop, IB_POLL_BUDGET_IRQ, ib_poll_handler);

+               if (cq->dim) {
+                       irq_poll_init(&cq->iop, IB_POLL_BUDGET_IRQ,
+                                     ib_poll_dim_handler);
+               } else
+                       irq_poll_init(&cq->iop, IB_POLL_BUDGET_IRQ,
+                                     ib_poll_handler);
+
                ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
                break;
        case IB_POLL_WORKQUEUE:
@@ -226,6 +290,9 @@ void ib_free_cq_user(struct ib_cq *cq, struct ib_udata 
*udata)
                WARN_ON_ONCE(1);
        }

+ if (cq->dim)

+               cancel_work_sync(&cq->dim->work);
+       kfree(cq->dim);
        kfree(cq->wc);
        rdma_restrack_del(&cq->res);
        ret = cq->device->ops.destroy_cq(cq, udata);
diff --git a/drivers/infiniband/hw/mlx5/main.c 
b/drivers/infiniband/hw/mlx5/main.c
index abac70ad5c7c..b1b45dbe24a5 100644
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -6305,6 +6305,8 @@ static int mlx5_ib_stage_caps_init(struct mlx5_ib_dev 
*dev)
             MLX5_CAP_GEN(dev->mdev, disable_local_lb_mc)))
                mutex_init(&dev->lb.mutex);

+ dev->ib_dev.use_cq_dim = true;

+

Please don't. This is a bad choice to opt it in by default.