In case the CQ is packed with completions, we can't just
hog the CPU forever. Poll until a sufficient budget (currently
hard-coded to 64k completions) and if budget is exhausted, bailout
and give a chance to other threads.
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
static void
isert_cq_work(struct work_struct *work)
{
+ enum { isert_poll_budget = 65536 };
struct isert_comp *comp = container_of(work, struct isert_comp,
work);
+ int completed = 0;
struct ib_wc wc;
- while (ib_poll_cq(comp->cq, 1, &wc) == 1)
+ while (ib_poll_cq(comp->cq, 1, &wc) == 1) {
isert_handle_wc(&wc);
+ if (++completed >= isert_poll_budget)
+ break;
+ }
+
ib_req_notify_cq(comp->cq, IB_CQ_NEXT_COMP);
}