Tune the vmbus connection so the host scans faster. This improves
transmit performance. The host default value is 100us but setting
to 50us reduces packet loss significantly.
Signed-off-by: Stephen Hemminger <sthem...@microsoft.com>
---
drivers/net/netvsc/hn_ethdev.c | 6 ++++++
drivers/net/netvsc/hn_var.h | 3 +++
2 files changed, 9 insertions(+)
diff --git a/drivers/net/netvsc/hn_ethdev.c b/drivers/net/netvsc/hn_ethdev.c
index 78b842ba2d68..148e6a33d682 100644
--- a/drivers/net/netvsc/hn_ethdev.c
+++ b/drivers/net/netvsc/hn_ethdev.c
@@ -264,6 +264,9 @@ static int hn_subchan_configure(struct hn_data *hv,
return err;
}
+ rte_vmbus_set_latency(hv->vmbus, new_sc,
+ HN_CHAN_LATENCY_NS);
+
retry = 0;
chn_index = rte_vmbus_sub_channel_index(new_sc);
if (chn_index == 0 || chn_index > hv->max_queues) {
@@ -629,6 +632,9 @@ eth_hn_dev_init(struct rte_eth_dev *eth_dev)
if (err)
return err;
+ rte_vmbus_set_latency(hv->vmbus, hv->channels[0],
+ HN_CHAN_LATENCY_NS);
+
hv->primary = hn_rx_queue_alloc(hv, 0,
eth_dev->device->numa_node);
diff --git a/drivers/net/netvsc/hn_var.h b/drivers/net/netvsc/hn_var.h
index f7ff8585bc1c..b3e0a93d45df 100644
--- a/drivers/net/netvsc/hn_var.h
+++ b/drivers/net/netvsc/hn_var.h
@@ -20,6 +20,9 @@
/* Retry interval */
#define HN_CHAN_INTERVAL_US 100
+/* Host monitor interval */
+#define HN_CHAN_LATENCY_NS 50000
+
/* Buffers need to be aligned */
#ifndef PAGE_SIZE
#define PAGE_SIZE 4096
--
2.18.0
