i40e: removed unreachable code

Removed some of unnecessary if statements and unreachable code found by
static code analysis tool.
The return value of i40e_vsi_control_rings(..., false) is always 0. So,
test for non-zero will never be true. The function has been split into
"int i40e_vsi_start_rings()" and "void i40e_vsi_stop_rings()" for better
understanding.
Similarly, the function i40e_vsi_kill_vlan() never fails. So, checking
for return value is also unnecessary. Function definition changed to void.
The i40e_loopback_test() function is not implemented. The function and
all references to loopback testing were removed.

Change-ID: Id45cf66f6689ce2bc4e887de13f073e30e8431bd
Signed-off-by: NFilip Sadowski <filip.sadowski@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40e/i40e.h

@@ -773,7 +773,8 @@ void i40e_service_event_schedule(struct i40e_pf *pf);
 void i40e_notify_client_of_vf_msg(struct i40e_vsi *vsi, u32 vf_id,
 				  u8 *msg, u16 len);
 
-int i40e_vsi_control_rings(struct i40e_vsi *vsi, bool enable);
+int i40e_vsi_start_rings(struct i40e_vsi *vsi);
+void i40e_vsi_stop_rings(struct i40e_vsi *vsi);
 int i40e_reconfig_rss_queues(struct i40e_pf *pf, int queue_count);
 struct i40e_veb *i40e_veb_setup(struct i40e_pf *pf, u16 flags, u16 uplink_seid,
 				u16 downlink_seid, u8 enabled_tc);
@@ -849,7 +850,7 @@ int i40e_close(struct net_device *netdev);
 int i40e_vsi_open(struct i40e_vsi *vsi);
 void i40e_vlan_stripping_disable(struct i40e_vsi *vsi);
 int i40e_vsi_add_vlan(struct i40e_vsi *vsi, s16 vid);
-int i40e_vsi_kill_vlan(struct i40e_vsi *vsi, s16 vid);
+void i40e_vsi_kill_vlan(struct i40e_vsi *vsi, s16 vid);
 struct i40e_mac_filter *i40e_put_mac_in_vlan(struct i40e_vsi *vsi,
 					     const u8 *macaddr);
 int i40e_del_mac_all_vlan(struct i40e_vsi *vsi, const u8 *macaddr);

drivers/net/ethernet/intel/i40e/i40e_ethtool.c

@@ -216,7 +216,6 @@ enum i40e_ethtool_test_id {
 	I40E_ETH_TEST_REG = 0,
 	I40E_ETH_TEST_EEPROM,
 	I40E_ETH_TEST_INTR,
-	I40E_ETH_TEST_LOOPBACK,
 	I40E_ETH_TEST_LINK,
 };
 
@@ -224,7 +223,6 @@ static const char i40e_gstrings_test[][ETH_GSTRING_LEN] = {
 	"Register test  (offline)",
 	"Eeprom test    (offline)",
 	"Interrupt test (offline)",
-	"Loopback test  (offline)",
 	"Link test   (on/offline)"
 };
 
@@ -1744,17 +1742,6 @@ static int i40e_intr_test(struct net_device *netdev, u64 *data)
 	return *data;
 }
 
-static int i40e_loopback_test(struct net_device *netdev, u64 *data)
-{
-	struct i40e_netdev_priv *np = netdev_priv(netdev);
-	struct i40e_pf *pf = np->vsi->back;
-
-	netif_info(pf, hw, netdev, "loopback test not implemented\n");
-	*data = 0;
-
-	return *data;
-}
-
 static inline bool i40e_active_vfs(struct i40e_pf *pf)
 {
 	struct i40e_vf *vfs = pf->vf;
@@ -1790,7 +1777,6 @@ static void i40e_diag_test(struct net_device *netdev,
 			data[I40E_ETH_TEST_REG]		= 1;
 			data[I40E_ETH_TEST_EEPROM]	= 1;
 			data[I40E_ETH_TEST_INTR]	= 1;
-			data[I40E_ETH_TEST_LOOPBACK]	= 1;
 			data[I40E_ETH_TEST_LINK]	= 1;
 			eth_test->flags |= ETH_TEST_FL_FAILED;
 			clear_bit(__I40E_TESTING, &pf->state);
@@ -1818,9 +1804,6 @@ static void i40e_diag_test(struct net_device *netdev,
 		if (i40e_intr_test(netdev, &data[I40E_ETH_TEST_INTR]))
 			eth_test->flags |= ETH_TEST_FL_FAILED;
 
-		if (i40e_loopback_test(netdev, &data[I40E_ETH_TEST_LOOPBACK]))
-			eth_test->flags |= ETH_TEST_FL_FAILED;
-
 		/* run reg test last, a reset is required after it */
 		if (i40e_reg_test(netdev, &data[I40E_ETH_TEST_REG]))
 			eth_test->flags |= ETH_TEST_FL_FAILED;
@@ -1841,7 +1824,6 @@ static void i40e_diag_test(struct net_device *netdev,
 		data[I40E_ETH_TEST_REG] = 0;
 		data[I40E_ETH_TEST_EEPROM] = 0;
 		data[I40E_ETH_TEST_INTR] = 0;
-		data[I40E_ETH_TEST_LOOPBACK] = 0;
 	}
 
 skip_ol_tests:

drivers/net/ethernet/intel/i40e/i40e_main.c

@@ -2503,10 +2503,8 @@ int i40e_vsi_add_vlan(struct i40e_vsi *vsi, s16 vid)
  * i40e_vsi_kill_vlan - Remove vsi membership for given vlan
  * @vsi: the vsi being configured
  * @vid: vlan id to be removed (0 = untagged only , -1 = any)
- *
- * Return: 0 on success or negative otherwise
  **/
-int i40e_vsi_kill_vlan(struct i40e_vsi *vsi, s16 vid)
+void i40e_vsi_kill_vlan(struct i40e_vsi *vsi, s16 vid)
 {
 	struct net_device *netdev = vsi->netdev;
 	struct i40e_mac_filter *f;
@@ -2530,7 +2528,6 @@ int i40e_vsi_kill_vlan(struct i40e_vsi *vsi, s16 vid)
 	 * applying the new filter changes
 	 */
 	i40e_service_event_schedule(vsi->back);
-	return 0;
 }
 
 /**
@@ -4017,29 +4014,35 @@ static int i40e_vsi_control_rx(struct i40e_vsi *vsi, bool enable)
 }
 
 /**
- * i40e_vsi_control_rings - Start or stop a VSI's rings
+ * i40e_vsi_start_rings - Start a VSI's rings
  * @vsi: the VSI being configured
- * @enable: start or stop the rings
  **/
-int i40e_vsi_control_rings(struct i40e_vsi *vsi, bool request)
+int i40e_vsi_start_rings(struct i40e_vsi *vsi)
 {
 	int ret = 0;
 
 	/* do rx first for enable and last for disable */
-	if (request) {
-		ret = i40e_vsi_control_rx(vsi, request);
-		if (ret)
-			return ret;
-		ret = i40e_vsi_control_tx(vsi, request);
-	} else {
-		/* Ignore return value, we need to shutdown whatever we can */
-		i40e_vsi_control_tx(vsi, request);
-		i40e_vsi_control_rx(vsi, request);
-	}
+	ret = i40e_vsi_control_rx(vsi, true);
+	if (ret)
+		return ret;
+	ret = i40e_vsi_control_tx(vsi, true);
 
 	return ret;
 }
 
+/**
+ * i40e_vsi_stop_rings - Stop a VSI's rings
+ * @vsi: the VSI being configured
+ **/
+void i40e_vsi_stop_rings(struct i40e_vsi *vsi)
+{
+	/* do rx first for enable and last for disable
+	 * Ignore return value, we need to shutdown whatever we can
+	 */
+	i40e_vsi_control_tx(vsi, false);
+	i40e_vsi_control_rx(vsi, false);
+}
+
 /**
  * i40e_vsi_free_irq - Free the irq association with the OS
  * @vsi: the VSI being configured
@@ -5238,7 +5241,7 @@ static int i40e_up_complete(struct i40e_vsi *vsi)
 		i40e_configure_msi_and_legacy(vsi);
 
 	/* start rings */
-	err = i40e_vsi_control_rings(vsi, true);
+	err = i40e_vsi_start_rings(vsi);
 	if (err)
 		return err;
 
@@ -5335,7 +5338,7 @@ void i40e_down(struct i40e_vsi *vsi)
 		netif_tx_disable(vsi->netdev);
 	}
 	i40e_vsi_disable_irq(vsi);
-	i40e_vsi_control_rings(vsi, false);
+	i40e_vsi_stop_rings(vsi);
 	i40e_napi_disable_all(vsi);
 
 	for (i = 0; i < vsi->num_queue_pairs; i++) {

drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c

@@ -991,7 +991,7 @@ void i40e_reset_vf(struct i40e_vf *vf, bool flr)
 	if (vf->lan_vsi_idx == 0)
 		goto complete_reset;
 
-	i40e_vsi_control_rings(pf->vsi[vf->lan_vsi_idx], false);
+	i40e_vsi_stop_rings(pf->vsi[vf->lan_vsi_idx]);
 complete_reset:
 	/* reallocate VF resources to reset the VSI state */
 	i40e_free_vf_res(vf);
@@ -1032,8 +1032,7 @@ void i40e_free_vfs(struct i40e_pf *pf)
 	i40e_notify_client_of_vf_enable(pf, 0);
 	for (i = 0; i < pf->num_alloc_vfs; i++)
 		if (test_bit(I40E_VF_STAT_INIT, &pf->vf[i].vf_states))
-			i40e_vsi_control_rings(pf->vsi[pf->vf[i].lan_vsi_idx],
-					       false);
+			i40e_vsi_stop_rings(pf->vsi[pf->vf[i].lan_vsi_idx]);
 
 	/* Disable IOV before freeing resources. This lets any VF drivers
 	 * running in the host get themselves cleaned up before we yank
@@ -1759,7 +1758,7 @@ static int i40e_vc_enable_queues_msg(struct i40e_vf *vf, u8 *msg, u16 msglen)
 		goto error_param;
 	}
 
-	if (i40e_vsi_control_rings(pf->vsi[vf->lan_vsi_idx], true))
+	if (i40e_vsi_start_rings(pf->vsi[vf->lan_vsi_idx]))
 		aq_ret = I40E_ERR_TIMEOUT;
 error_param:
 	/* send the response to the VF */
@@ -1798,8 +1797,7 @@ static int i40e_vc_disable_queues_msg(struct i40e_vf *vf, u8 *msg, u16 msglen)
 		goto error_param;
 	}
 
-	if (i40e_vsi_control_rings(pf->vsi[vf->lan_vsi_idx], false))
-		aq_ret = I40E_ERR_TIMEOUT;
+	i40e_vsi_stop_rings(pf->vsi[vf->lan_vsi_idx]);
 
 error_param:
 	/* send the response to the VF */
@@ -2139,9 +2137,8 @@ static int i40e_vc_remove_vlan_msg(struct i40e_vf *vf, u8 *msg, u16 msglen)
 	}
 
 	for (i = 0; i < vfl->num_elements; i++) {
-		int ret = i40e_vsi_kill_vlan(vsi, vfl->vlan_id[i]);
-		if (!ret)
-			vf->num_vlan--;
+		i40e_vsi_kill_vlan(vsi, vfl->vlan_id[i]);
+		vf->num_vlan--;
 
 		if (test_bit(I40E_VF_STAT_UC_PROMISC, &vf->vf_states))
 			i40e_aq_set_vsi_uc_promisc_on_vlan(&pf->hw, vsi->seid,
@@ -2153,11 +2150,6 @@ static int i40e_vc_remove_vlan_msg(struct i40e_vf *vf, u8 *msg, u16 msglen)
 							   false,
 							   vfl->vlan_id[i],
 							   NULL);
-
-		if (ret)
-			dev_err(&pf->pdev->dev,
-				"Unable to delete VLAN filter %d for VF %d, error %d\n",
-				vfl->vlan_id[i], vf->vf_id, ret);
 	}
 
 error_param:
@@ -2835,13 +2827,8 @@ int i40e_ndo_set_vf_port_vlan(struct net_device *netdev, int vf_id,
 
 	if (vsi->info.pvid) {
 		/* kill old VLAN */
-		ret = i40e_vsi_kill_vlan(vsi, (le16_to_cpu(vsi->info.pvid) &
-					       VLAN_VID_MASK));
-		if (ret) {
-			dev_info(&vsi->back->pdev->dev,
-				 "remove VLAN failed, ret=%d, aq_err=%d\n",
-				 ret, pf->hw.aq.asq_last_status);
-		}
+		i40e_vsi_kill_vlan(vsi, (le16_to_cpu(vsi->info.pvid) &
+					 VLAN_VID_MASK));
 	}
 	if (vlan_id || qos)
 		ret = i40e_vsi_add_pvid(vsi, vlanprio);