Currently activated via modparam, obviously we will want to
find a more generic way to control this.
Signed-off-by: Sagi Grimberg <s...@grimberg.me>
---
drivers/infiniband/core/cq.c | 48 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 48 insertions(+)
diff --git a/drivers/infiniband/core/cq.c b/drivers/infiniband/core/cq.c
index f2ae75fa3128..270801d28f9d 100644
--- a/drivers/infiniband/core/cq.c
+++ b/drivers/infiniband/core/cq.c
@@ -25,6 +25,51 @@
#define IB_POLL_FLAGS \
(IB_CQ_NEXT_COMP | IB_CQ_REPORT_MISSED_EVENTS)
+#define IB_CQ_AM_NR_LEVELS 8
+#define IB_CQ_AM_NR_EVENTS 64
+
+struct ib_cq_moder {
+ u16 usec;
+ u16 comps;
+};
+
+/* XXX: magic adaptive moderation profiles */
+static const struct ib_cq_moder am_prof[IB_CQ_AM_NR_LEVELS] = {
+ {1, 1},
+ {1, 2},
+ {2, 4},
+ {4, 8},
+ {8, 16},
+ {16, 32},
+ {32, 48},
+ {32, 64},
+};
+
+static bool use_am = true;
+module_param(use_am, bool, 0444);
+MODULE_PARM_DESC(use_am, "Use cq adaptive moderation");
+
+static int ib_cq_am(struct ib_cq *cq, unsigned short level)
+{
+ u16 usec;
+ u16 comps;
+
+ if (!use_am)
+ return 0;
+
+ usec = am_prof[level].usec;
+ comps = am_prof[level].comps;
+
+ return cq->device->modify_cq(cq, comps, usec);
+}
+
+static int ib_cq_irqpoll_am(struct irq_poll *iop, unsigned short level)
+{
+ struct ib_cq *cq = container_of(iop, struct ib_cq, iop);
+
+ return ib_cq_am(cq, level);
+}
+
static int __ib_process_cq(struct ib_cq *cq, int budget)
{
int i, n, completed = 0;
@@ -162,6 +207,9 @@ struct ib_cq *ib_alloc_cq(struct ib_device *dev, void
*private,
cq->comp_handler = ib_cq_completion_softirq;
irq_poll_init(&cq->iop, IB_POLL_BUDGET_IRQ, ib_poll_handler);
+ if (cq->device->modify_cq)
+ irq_poll_init_am(&cq->iop, IB_CQ_AM_NR_EVENTS,
+ IB_CQ_AM_NR_LEVELS, 0, ib_cq_irqpoll_am);
ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
break;
case IB_POLL_WORKQUEUE:
--
2.14.1
