On 5/20/2020 1:50 PM, Devesh Sharma wrote:
On Wed, May 20, 2020 at 2:53 PM Yamin Friedman <yaminf@xxxxxxxxxxxx> wrote:
On 5/20/2020 9:19 AM, Devesh Sharma wrote:
+
+static int ib_alloc_cqs(struct ib_device *dev, int nr_cqes,
+ enum ib_poll_context poll_ctx)
+{
+ LIST_HEAD(tmp_list);
+ struct ib_cq *cq;
+ unsigned long flags;
+ int nr_cqs, ret, i;
+
+ /*
+ * Allocated at least as many CQEs as requested, and otherwise
+ * a reasonable batch size so that we can share CQs between
+ * multiple users instead of allocating a larger number of CQs.
+ */
+ nr_cqes = min(dev->attrs.max_cqe, max(nr_cqes, IB_MAX_SHARED_CQ_SZ));
+ nr_cqs = min_t(int, dev->num_comp_vectors, num_online_cpus());
No WARN() or return with failure as pointed by Leon and me. Has
anything else changes elsewhere?
Hey Devesh,
I am not sure what you are referring to, could you please clarify?
I thought on V2 Leon gave a comment "how this will work if
dev->num_comp_vectors" is 0.
there I had suggested to fail the pool creation and issue a
WARN_ONCE() or something.
I understood his comment to be regarding if the comp_vector itself is 0.
There should not be any issue with that case.
As far as I am aware there must be a non-zero amount of comp_vectors for
the ib_dev otherwise we will not be able to get any indication for cqes.
I don't see any reason to add a special check here.
Thanks
+ for (i = 0; i < nr_cqs; i++) {
+ cq = ib_alloc_cq(dev, NULL, nr_cqes, i, poll_ctx);
+ if (IS_ERR(cq)) {
+ ret = PTR_ERR(cq);
+ goto out_free_cqs;
+ }
+ cq->shared = true;
+ list_add_tail(&cq->pool_entry, &tmp_list);
+ }
+
+ spin_lock_irqsave(&dev->cq_pools_lock, flags);
+ list_splice(&tmp_list, &dev->cq_pools[poll_ctx - 1]);
+ spin_unlock_irqrestore(&dev->cq_pools_lock, flags);
+
+ return 0;
+
+out_free_cqs:
+ list_for_each_entry(cq, &tmp_list, pool_entry) {
+ cq->shared = false;
+ ib_free_cq(cq);
+ }
+ return ret;
+}
+
