From: Julian Wiedmann <jwi@linux.ibm.com>
Subject: s390/qeth: add stats counter for RX csum offload
Patch-mainline: v4.18-rc1
Git-commit: 3aade31b2f2dce54d988a42d2e1974c82b25fccf
References: FATE#326350, LTC#169511, bsc#1113509

Summary:     qeth: performance improvements
Description: This adds recent functional and performance improvements for the
             qeth network driver.
             Primarily this brings Scatter-Gather support for HiperSockets,
             reduced CPU consumption in the L3 IPv4 transmit path for OSA,
             improved Promiscuous Mode performance due to IFF_UNICAST_FLT,
             support for Scatter-Gather on z/VM virtual NICs, and
             support for delayed GRO flushing.

             For sanity & stability reasons, this effectively constitutes a
             backport of the qeth device driver from 4.19 mainline.
             

Upstream-Description:

             s390/qeth: add stats counter for RX csum offload

             This matches the statistics we gather for the TX offload path.

             Signed-off-by: Kittipon Meesompop <kmeesomp@linux.vnet.ibm.com>
             Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
             Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/s390/net/qeth_core.h      |    8 ++++++--
 drivers/s390/net/qeth_core_main.c |    4 +++-
 2 files changed, 9 insertions(+), 3 deletions(-)

--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -146,6 +146,7 @@ struct qeth_perf_stats {
 	unsigned int tx_csum;
 	unsigned int tx_lin;
 	unsigned int tx_linfail;
+	unsigned int rx_csum;
 };
 
 /* Routing stuff */
@@ -877,10 +878,13 @@ static inline void qeth_rx_csum(struct q
 				u8 flags)
 {
 	if ((card->dev->features & NETIF_F_RXCSUM) &&
-	    (flags & QETH_HDR_EXT_CSUM_TRANSP_REQ))
+	    (flags & QETH_HDR_EXT_CSUM_TRANSP_REQ)) {
 		skb->ip_summed = CHECKSUM_UNNECESSARY;
-	else
+		if (card->options.performance_stats)
+			card->perf_stats.rx_csum++;
+	} else {
 		skb->ip_summed = CHECKSUM_NONE;
+	}
 }
 
 static inline void qeth_tx_csum(struct sk_buff *skb, u8 *flags)
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -6016,7 +6016,8 @@ static struct {
 	{"tx lin"},
 	{"tx linfail"},
 	{"cq handler count"},
-	{"cq handler time"}
+	{"cq handler time"},
+	{"rx csum"}
 };
 
 int qeth_core_get_sset_count(struct net_device *dev, int stringset)
@@ -6078,6 +6079,7 @@ void qeth_core_get_ethtool_stats(struct
 	data[35] = card->perf_stats.tx_linfail;
 	data[36] = card->perf_stats.cq_cnt;
 	data[37] = card->perf_stats.cq_time;
+	data[38] = card->perf_stats.rx_csum;
 }
 EXPORT_SYMBOL_GPL(qeth_core_get_ethtool_stats);