0001-Fixing-Pktgen-issue-at-lower-rates.patch

From 3b6c3c05a7c5dee92bc1fdac8105ff6348c73e93 Mon Sep 17 00:00:00 2001
From: Ashish Kashinath <akashina@eng.ucsd.edu>
Date: Wed, 1 May 2019 20:57:38 +0000
Subject: [PATCH 1/3] Fixing Pktgen issue at lower rates

Pktgen is giving variabilities in timing measurements
at low rates(~10Mbps) and seems more reliable at high rates(~80Mbps).

This seems to be an aritfact of the hrtimer implementation at
different packet delays.

Signed-off-by: Ashish Kashinath <akashina@eng.ucsd.edu>
---
 net/core/pktgen.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index 6e1e10ff4..33ff023ad 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -3382,6 +3382,7 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev)
 	struct netdev_queue *txq;
 	struct sk_buff *skb;
 	int ret;
+	__u64 temp;
 
 	/* If device is offline, then don't send */
 	if (unlikely(!netif_running(odev) || !netif_carrier_ok(odev))) {
@@ -3490,7 +3491,11 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev)
 	refcount_add(burst, &pkt_dev->skb->users);
 
 xmit_more:
-	ret = netdev_start_xmit(pkt_dev->skb, odev, txq, --burst > 0);
+	temp = pkt_dev->sofar;
+	if(do_div(temp,11)==0)
+		ret = netdev_start_xmit(pkt_dev->skb, odev, txq, --burst > 0);
+	else
+		ret = NETDEV_TX_OK;
 
 	switch (ret) {
 	case NETDEV_TX_OK:
-- 
2.11.0