net/iavf: fix performance with writeback policy

[dpdk.git] / drivers / net / iavf / iavf_ethdev.c

diff --git a/drivers/net/iavf/iavf_ethdev.c b/drivers/net/iavf/iavf_ethdev.c
index 92dd141..d12a236 100644 (file)
--- a/drivers/net/iavf/iavf_ethdev.c
+++ b/drivers/net/iavf/iavf_ethdev.c
@@ -474,10 +474,19 @@ static int iavf_config_rx_queues_irqs(struct rte_eth_dev *dev,
                    VIRTCHNL_VF_OFFLOAD_WB_ON_ITR) {
                        /* If WB_ON_ITR supports, enable it */
                        vf->msix_base = IAVF_RX_VEC_START;
+                       /* Set the ITR for index zero, to 2us to make sure that
+                        * we leave time for aggregation to occur, but don't
+                        * increase latency dramatically.
+                        */
                        IAVF_WRITE_REG(hw,
                                       IAVF_VFINT_DYN_CTLN1(vf->msix_base - 1),
-                                      IAVF_VFINT_DYN_CTLN1_ITR_INDX_MASK |
-                                      IAVF_VFINT_DYN_CTLN1_WB_ON_ITR_MASK);
+                                      (0 << IAVF_VFINT_DYN_CTLN1_ITR_INDX_SHIFT) |
+                                      IAVF_VFINT_DYN_CTLN1_WB_ON_ITR_MASK |
+                                      (2UL << IAVF_VFINT_DYN_CTLN1_INTERVAL_SHIFT));
+                       /* debug - check for success! the return value
+                        * should be 2, offset is 0x2800
+                        */
+                       /* IAVF_READ_REG(hw, IAVF_VFINT_ITRN1(0, 0)); */
                } else {
                        /* If no WB_ON_ITR offload flags, need to set
                         * interrupt for descriptor write back.