From: Intiyaz Basha <intiyaz.basha@cavium.com>
Date: Sun, 9 Sep 2018 23:34:16 -0700
Subject: liquidio: Disabling tasklet when NAPI is active
Patch-mainline: v4.20-rc1
Git-commit: fe2d22b17288303ebd8ed7ded8ec5133e47d4957
References: bsc#1119406 FATE#326562

Control packets are processed in tasklet when interface is down and in
NAPI when interface is up. So tasklet can be disabled when interface up
and re-enabled when interface is down.

Signed-off-by: Intiyaz Basha <intiyaz.basha@cavium.com>
Acked-by: Derek Chickles <derek.chickles@cavium.com>
Signed-off-by: Felix Manlunas <felix.manlunas@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/cavium/liquidio/lio_main.c    |   14 +++++++++++++-
 drivers/net/ethernet/cavium/liquidio/lio_vf_main.c |   16 ++++++++++++++++
 2 files changed, 29 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/cavium/liquidio/lio_main.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_main.c
@@ -1239,8 +1239,10 @@ static void send_rx_ctrl_cmd(struct lio
 static void liquidio_destroy_nic_device(struct octeon_device *oct, int ifidx)
 {
 	struct net_device *netdev = oct->props[ifidx].netdev;
-	struct lio *lio;
+	struct octeon_device_priv *oct_priv =
+		(struct octeon_device_priv *)oct->priv;
 	struct napi_struct *napi, *n;
+	struct lio *lio;
 
 	if (!netdev) {
 		dev_err(&oct->pci_dev->dev, "%s No netdevice ptr for index %d\n",
@@ -1269,6 +1271,8 @@ static void liquidio_destroy_nic_device(
 	list_for_each_entry_safe(napi, n, &netdev->napi_list, dev_list)
 		netif_napi_del(napi);
 
+	tasklet_enable(&oct_priv->droq_tasklet);
+
 	if (atomic_read(&lio->ifstate) & LIO_IFSTATE_REGISTERED)
 		unregister_netdev(netdev);
 
@@ -1805,9 +1809,13 @@ static int liquidio_open(struct net_devi
 {
 	struct lio *lio = GET_LIO(netdev);
 	struct octeon_device *oct = lio->oct_dev;
+	struct octeon_device_priv *oct_priv =
+		(struct octeon_device_priv *)oct->priv;
 	struct napi_struct *napi, *n;
 
 	if (oct->props[lio->ifidx].napi_enabled == 0) {
+		tasklet_disable(&oct_priv->droq_tasklet);
+
 		list_for_each_entry_safe(napi, n, &netdev->napi_list, dev_list)
 			napi_enable(napi);
 
@@ -1861,6 +1869,8 @@ static int liquidio_stop(struct net_devi
 {
 	struct lio *lio = GET_LIO(netdev);
 	struct octeon_device *oct = lio->oct_dev;
+	struct octeon_device_priv *oct_priv =
+		(struct octeon_device_priv *)oct->priv;
 	struct napi_struct *napi, *n;
 
 	ifstate_reset(lio, LIO_IFSTATE_RUNNING);
@@ -1907,6 +1917,8 @@ static int liquidio_stop(struct net_devi
 
 		if (OCTEON_CN23XX_PF(oct))
 			oct->droq[0]->ops.poll_mode = 0;
+
+		tasklet_enable(&oct_priv->droq_tasklet);
 	}
 
 	dev_info(&oct->pci_dev->dev, "%s interface is stopped\n", netdev->name);
--- a/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
@@ -444,6 +444,8 @@ static void octeon_pci_flr(struct octeon
  */
 static void octeon_destroy_resources(struct octeon_device *oct)
 {
+	struct octeon_device_priv *oct_priv =
+		(struct octeon_device_priv *)oct->priv;
 	struct msix_entry *msix_entries;
 	int i;
 
@@ -587,6 +589,8 @@ static void octeon_destroy_resources(str
 		/* Nothing to be done here either */
 		break;
 	}
+
+	tasklet_kill(&oct_priv->droq_tasklet);
 }
 
 /**
@@ -652,6 +656,8 @@ static void send_rx_ctrl_cmd(struct lio
 static void liquidio_destroy_nic_device(struct octeon_device *oct, int ifidx)
 {
 	struct net_device *netdev = oct->props[ifidx].netdev;
+	struct octeon_device_priv *oct_priv =
+		(struct octeon_device_priv *)oct->priv;
 	struct napi_struct *napi, *n;
 	struct lio *lio;
 
@@ -681,6 +687,8 @@ static void liquidio_destroy_nic_device(
 	list_for_each_entry_safe(napi, n, &netdev->napi_list, dev_list)
 		netif_napi_del(napi);
 
+	tasklet_enable(&oct_priv->droq_tasklet);
+
 	if (atomic_read(&lio->ifstate) & LIO_IFSTATE_REGISTERED)
 		unregister_netdev(netdev);
 
@@ -898,9 +906,13 @@ static int liquidio_open(struct net_devi
 {
 	struct lio *lio = GET_LIO(netdev);
 	struct octeon_device *oct = lio->oct_dev;
+	struct octeon_device_priv *oct_priv =
+		(struct octeon_device_priv *)oct->priv;
 	struct napi_struct *napi, *n;
 
 	if (!oct->props[lio->ifidx].napi_enabled) {
+		tasklet_disable(&oct_priv->droq_tasklet);
+
 		list_for_each_entry_safe(napi, n, &netdev->napi_list, dev_list)
 			napi_enable(napi);
 
@@ -938,6 +950,8 @@ static int liquidio_stop(struct net_devi
 {
 	struct lio *lio = GET_LIO(netdev);
 	struct octeon_device *oct = lio->oct_dev;
+	struct octeon_device_priv *oct_priv =
+		(struct octeon_device_priv *)oct->priv;
 	struct napi_struct *napi, *n;
 
 	/* tell Octeon to stop forwarding packets to host */
@@ -967,6 +981,8 @@ static int liquidio_stop(struct net_devi
 		oct->props[lio->ifidx].napi_enabled = 0;
 
 		oct->droq[0]->ops.poll_mode = 0;
+
+		tasklet_enable(&oct_priv->droq_tasklet);
 	}
 
 	cancel_delayed_work_sync(&lio->stats_wk.work);