Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/next-queue

Jeff Kirsher says:

====================
Intel Wired LAN Driver Updates 2015-09-28

This series contains updates to i40e, i40evf and igb to resolve issues
seen and reported by Red Hat.

Kiran moves i40e_get_head() in preparation for the refactor of the Tx
timeout logic, so that it can be used in other areas of the driver.
Refactored the driver timeout logic by issuing a writeback request via
a software interrupt to the hardware the first time the driver detects
a hang.  This was due to the driver being too aggressive in resetting a
hung queue.

Shannon adds the GRE protocol to the transmit checksum encoding.

Anjali fixes an issue of forcing writeback too often, which caused us to
not benefit from NAPI.  We now disable force writeback in the clean
routine for X710 and XL710 adapters.  The X722 adapters do not enable
interrupt to force a writeback and benefit from WB_ON_ITR and so force
WB is left enabled for those adapters.  Fixed a possible deadlock issue
where sync_vsi_filters() can be called directly under RTNL or through
the timer subtask without RTNL.  So update the flow to see if we are
already under RTNL before trying to grab it.

Stefan Assmann provides a fix for igb where SR-IOV was not getting
enabled properly and we ran into a NULL pointer if the max_vfs module
parameter is specified.  This is prevented by setting the
IGB_FLAG_HAS_MSIX bit before calling igb_probe_vfs().

v2: added "i40e: Fix for recursive RTNL lock during PROMISC change" patch
    to the series, as it resolves another issues seen and reported by
    Red Hat.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 173 insertions, 118 deletions

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 530d8b6739f9..52e58f304b21 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -299,25 +299,69 @@ static void i40e_tx_timeout(struct net_device *netdev)
 	struct i40e_netdev_priv *np = netdev_priv(netdev);
 	struct i40e_vsi *vsi = np->vsi;
 	struct i40e_pf *pf = vsi->back;
+	struct i40e_ring *tx_ring = NULL;
+	unsigned int i, hung_queue = 0;
+	u32 head, val;
 
 	pf->tx_timeout_count++;
 
+	/* find the stopped queue the same way the stack does */
+	for (i = 0; i < netdev->num_tx_queues; i++) {
+		struct netdev_queue *q;
+		unsigned long trans_start;
+
+		q = netdev_get_tx_queue(netdev, i);
+		trans_start = q->trans_start ? : netdev->trans_start;
+		if (netif_xmit_stopped(q) &&
+		    time_after(jiffies,
+			       (trans_start + netdev->watchdog_timeo))) {
+			hung_queue = i;
+			break;
+		}
+	}
+
+	if (i == netdev->num_tx_queues) {
+		netdev_info(netdev, "tx_timeout: no netdev hung queue found\n");
+	} else {
+		/* now that we have an index, find the tx_ring struct */
+		for (i = 0; i < vsi->num_queue_pairs; i++) {
+			if (vsi->tx_rings[i] && vsi->tx_rings[i]->desc) {
+				if (hung_queue ==
+				    vsi->tx_rings[i]->queue_index) {
+					tx_ring = vsi->tx_rings[i];
+					break;
+				}
+			}
+		}
+	}
+
 	if (time_after(jiffies, (pf->tx_timeout_last_recovery + HZ*20)))
-		pf->tx_timeout_recovery_level = 1;
+		pf->tx_timeout_recovery_level = 1;  /* reset after some time */
+	else if (time_before(jiffies,
+		      (pf->tx_timeout_last_recovery + netdev->watchdog_timeo)))
+		return;   /* don't do any new action before the next timeout */
+
+	if (tx_ring) {
+		head = i40e_get_head(tx_ring);
+		/* Read interrupt register */
+		if (pf->flags & I40E_FLAG_MSIX_ENABLED)
+			val = rd32(&pf->hw,
+			     I40E_PFINT_DYN_CTLN(tx_ring->q_vector->v_idx +
+						tx_ring->vsi->base_vector - 1));
+		else
+			val = rd32(&pf->hw, I40E_PFINT_DYN_CTL0);
+
+		netdev_info(netdev, "tx_timeout: VSI_seid: %d, Q %d, NTC: 0x%x, HWB: 0x%x, NTU: 0x%x, TAIL: 0x%x, INT: 0x%x\n",
+			    vsi->seid, hung_queue, tx_ring->next_to_clean,
+			    head, tx_ring->next_to_use,
+			    readl(tx_ring->tail), val);
+	}
+
 	pf->tx_timeout_last_recovery = jiffies;
-	netdev_info(netdev, "tx_timeout recovery level %d\n",
-		    pf->tx_timeout_recovery_level);
+	netdev_info(netdev, "tx_timeout recovery level %d, hung_queue %d\n",
+		    pf->tx_timeout_recovery_level, hung_queue);
 
 	switch (pf->tx_timeout_recovery_level) {
-	case 0:
-		/* disable and re-enable queues for the VSI */
-		if (in_interrupt()) {
-			set_bit(__I40E_REINIT_REQUESTED, &pf->state);
-			set_bit(__I40E_REINIT_REQUESTED, &vsi->state);
-		} else {
-			i40e_vsi_reinit_locked(vsi);
-		}
-		break;
 	case 1:
 		set_bit(__I40E_PF_RESET_REQUESTED, &pf->state);
 		break;
@@ -329,10 +373,9 @@ static void i40e_tx_timeout(struct net_device *netdev)
 		break;
 	default:
 		netdev_err(netdev, "tx_timeout recovery unsuccessful\n");
-		set_bit(__I40E_DOWN_REQUESTED, &pf->state);
-		set_bit(__I40E_DOWN_REQUESTED, &vsi->state);
 		break;
 	}
+
 	i40e_service_event_schedule(pf);
 	pf->tx_timeout_recovery_level++;
 }
@@ -754,7 +797,6 @@ static void i40e_update_link_xoff_rx(struct i40e_pf *pf)
 	struct i40e_hw_port_stats *nsd = &pf->stats;
 	struct i40e_hw *hw = &pf->hw;
 	u64 xoff = 0;
-	u16 i, v;
 
 	if ((hw->fc.current_mode != I40E_FC_FULL) &&
 	    (hw->fc.current_mode != I40E_FC_RX_PAUSE))
@@ -769,18 +811,6 @@ static void i40e_update_link_xoff_rx(struct i40e_pf *pf)
 	if (!(nsd->link_xoff_rx - xoff))
 		return;
 
-	/* Clear the __I40E_HANG_CHECK_ARMED bit for all Tx rings */
-	for (v = 0; v < pf->num_alloc_vsi; v++) {
-		struct i40e_vsi *vsi = pf->vsi[v];
-
-		if (!vsi || !vsi->tx_rings[0])
-			continue;
-
-		for (i = 0; i < vsi->num_queue_pairs; i++) {
-			struct i40e_ring *ring = vsi->tx_rings[i];
-			clear_bit(__I40E_HANG_CHECK_ARMED, &ring->state);
-		}
-	}
 }
 
 /**
@@ -796,7 +826,7 @@ static void i40e_update_prio_xoff_rx(struct i40e_pf *pf)
 	bool xoff[I40E_MAX_TRAFFIC_CLASS] = {false};
 	struct i40e_dcbx_config *dcb_cfg;
 	struct i40e_hw *hw = &pf->hw;
-	u16 i, v;
+	u16 i;
 	u8 tc;
 
 	dcb_cfg = &hw->local_dcbx_config;
@@ -821,23 +851,6 @@ static void i40e_update_prio_xoff_rx(struct i40e_pf *pf)
 		tc = dcb_cfg->etscfg.prioritytable[i];
 		xoff[tc] = true;
 	}
-
-	/* Clear the __I40E_HANG_CHECK_ARMED bit for Tx rings */
-	for (v = 0; v < pf->num_alloc_vsi; v++) {
-		struct i40e_vsi *vsi = pf->vsi[v];
-
-		if (!vsi || !vsi->tx_rings[0])
-			continue;
-
-		for (i = 0; i < vsi->num_queue_pairs; i++) {
-			struct i40e_ring *ring = vsi->tx_rings[i];
-
-			tc = ring->dcb_tc;
-			if (xoff[tc])
-				clear_bit(__I40E_HANG_CHECK_ARMED,
-					  &ring->state);
-		}
-	}
 }
 
 /**
@@ -1514,7 +1527,7 @@ static int i40e_set_mac(struct net_device *netdev, void *p)
 			f->is_laa = true;
 	}
 
-	i40e_sync_vsi_filters(vsi);
+	i40e_sync_vsi_filters(vsi, false);
 	ether_addr_copy(netdev->dev_addr, addr->sa_data);
 
 	return 0;
@@ -1751,12 +1764,13 @@ static void i40e_set_rx_mode(struct net_device *netdev)
 /**
  * i40e_sync_vsi_filters - Update the VSI filter list to the HW
  * @vsi: ptr to the VSI
+ * @grab_rtnl: whether RTNL needs to be grabbed
  *
  * Push any outstanding VSI filter changes through the AdminQ.
  *
  * Returns 0 or error value
  **/
-int i40e_sync_vsi_filters(struct i40e_vsi *vsi)
+int i40e_sync_vsi_filters(struct i40e_vsi *vsi, bool grab_rtnl)
 {
 	struct i40e_mac_filter *f, *ftmp;
 	bool promisc_forced_on = false;
@@ -1945,7 +1959,11 @@ int i40e_sync_vsi_filters(struct i40e_vsi *vsi)
 			 */
 			if (pf->cur_promisc != cur_promisc) {
 				pf->cur_promisc = cur_promisc;
-				i40e_do_reset_safe(pf,
+				if (grab_rtnl)
+					i40e_do_reset_safe(pf,
+						BIT(__I40E_PF_RESET_REQUESTED));
+				else
+					i40e_do_reset(pf,
 						BIT(__I40E_PF_RESET_REQUESTED));
 			}
 		} else {
@@ -1996,7 +2014,7 @@ static void i40e_sync_filters_subtask(struct i40e_pf *pf)
 	for (v = 0; v < pf->num_alloc_vsi; v++) {
 		if (pf->vsi[v] &&
 		    (pf->vsi[v]->flags & I40E_VSI_FLAG_FILTER_CHANGED))
-			i40e_sync_vsi_filters(pf->vsi[v]);
+			i40e_sync_vsi_filters(pf->vsi[v], true);
 	}
 }
 
@@ -2203,7 +2221,7 @@ int i40e_vsi_add_vlan(struct i40e_vsi *vsi, s16 vid)
 	    test_bit(__I40E_RESET_RECOVERY_PENDING, &vsi->back->state))
 		return 0;
 
-	return i40e_sync_vsi_filters(vsi);
+	return i40e_sync_vsi_filters(vsi, false);
 }
 
 /**
@@ -2275,7 +2293,7 @@ int i40e_vsi_kill_vlan(struct i40e_vsi *vsi, s16 vid)
 	    test_bit(__I40E_RESET_RECOVERY_PENDING, &vsi->back->state))
 		return 0;
 
-	return i40e_sync_vsi_filters(vsi);
+	return i40e_sync_vsi_filters(vsi, false);
 }
 
 /**
@@ -2609,8 +2627,6 @@ static int i40e_configure_tx_ring(struct i40e_ring *ring)
 	wr32(hw, I40E_QTX_CTL(pf_q), qtx_ctl);
 	i40e_flush(hw);
 
-	clear_bit(__I40E_HANG_CHECK_ARMED, &ring->state);
-
 	/* cache tail off for easier writes later */
 	ring->tail = hw->hw_addr + I40E_QTX_TAIL(pf_q);
 
@@ -4145,6 +4161,108 @@ static int i40e_pf_wait_txq_disabled(struct i40e_pf *pf)
 }
 
 #endif
+
+/**
+ * i40e_detect_recover_hung_queue - Function to detect and recover hung_queue
+ * @q_idx: TX queue number
+ * @vsi: Pointer to VSI struct
+ *
+ * This function checks specified queue for given VSI. Detects hung condition.
+ * Sets hung bit since it is two step process. Before next run of service task
+ * if napi_poll runs, it reset 'hung' bit for respective q_vector. If not,
+ * hung condition remain unchanged and during subsequent run, this function
+ * issues SW interrupt to recover from hung condition.
+ **/
+static void i40e_detect_recover_hung_queue(int q_idx, struct i40e_vsi *vsi)
+{
+	struct i40e_ring *tx_ring = NULL;
+	struct i40e_pf	*pf;
+	u32 head, val, tx_pending;
+	int i;
+
+	pf = vsi->back;
+
+	/* now that we have an index, find the tx_ring struct */
+	for (i = 0; i < vsi->num_queue_pairs; i++) {
+		if (vsi->tx_rings[i] && vsi->tx_rings[i]->desc) {
+			if (q_idx == vsi->tx_rings[i]->queue_index) {
+				tx_ring = vsi->tx_rings[i];
+				break;
+			}
+		}
+	}
+
+	if (!tx_ring)
+		return;
+
+	/* Read interrupt register */
+	if (pf->flags & I40E_FLAG_MSIX_ENABLED)
+		val = rd32(&pf->hw,
+			   I40E_PFINT_DYN_CTLN(tx_ring->q_vector->v_idx +
+					       tx_ring->vsi->base_vector - 1));
+	else
+		val = rd32(&pf->hw, I40E_PFINT_DYN_CTL0);
+
+	head = i40e_get_head(tx_ring);
+
+	tx_pending = i40e_get_tx_pending(tx_ring);
+
+	/* Interrupts are disabled and TX pending is non-zero,
+	 * trigger the SW interrupt (don't wait). Worst case
+	 * there will be one extra interrupt which may result
+	 * into not cleaning any queues because queues are cleaned.
+	 */
+	if (tx_pending && (!(val & I40E_PFINT_DYN_CTLN_INTENA_MASK)))
+		i40e_force_wb(vsi, tx_ring->q_vector);
+}
+
+/**
+ * i40e_detect_recover_hung - Function to detect and recover hung_queues
+ * @pf:  pointer to PF struct
+ *
+ * LAN VSI has netdev and netdev has TX queues. This function is to check
+ * each of those TX queues if they are hung, trigger recovery by issuing
+ * SW interrupt.
+ **/
+static void i40e_detect_recover_hung(struct i40e_pf *pf)
+{
+	struct net_device *netdev;
+	struct i40e_vsi *vsi;
+	int i;
+
+	/* Only for LAN VSI */
+	vsi = pf->vsi[pf->lan_vsi];
+
+	if (!vsi)
+		return;
+
+	/* Make sure, VSI state is not DOWN/RECOVERY_PENDING */
+	if (test_bit(__I40E_DOWN, &vsi->back->state) ||
+	    test_bit(__I40E_RESET_RECOVERY_PENDING, &vsi->back->state))
+		return;
+
+	/* Make sure type is MAIN VSI */
+	if (vsi->type != I40E_VSI_MAIN)
+		return;
+
+	netdev = vsi->netdev;
+	if (!netdev)
+		return;
+
+	/* Bail out if netif_carrier is not OK */
+	if (!netif_carrier_ok(netdev))
+		return;
+
+	/* Go thru' TX queues for netdev */
+	for (i = 0; i < netdev->num_tx_queues; i++) {
+		struct netdev_queue *q;
+
+		q = netdev_get_tx_queue(netdev, i);
+		if (q)
+			i40e_detect_recover_hung_queue(i, vsi);
+	}
+}
+
 /**
  * i40e_get_iscsi_tc_map - Return TC map for iSCSI APP
  * @pf: pointer to PF
@@ -5759,68 +5877,6 @@ static void i40e_link_event(struct i40e_pf *pf)
 }
 
 /**
- * i40e_check_hang_subtask - Check for hung queues and dropped interrupts
- * @pf: board private structure
- *
- * Set the per-queue flags to request a check for stuck queues in the irq
- * clean functions, then force interrupts to be sure the irq clean is called.
- **/
-static void i40e_check_hang_subtask(struct i40e_pf *pf)
-{
-	int i, v;
-
-	/* If we're down or resetting, just bail */
-	if (test_bit(__I40E_DOWN, &pf->state) ||
-	    test_bit(__I40E_CONFIG_BUSY, &pf->state))
-		return;
-
-	/* for each VSI/netdev
-	 *     for each Tx queue
-	 *         set the check flag
-	 *     for each q_vector
-	 *         force an interrupt
-	 */
-	for (v = 0; v < pf->num_alloc_vsi; v++) {
-		struct i40e_vsi *vsi = pf->vsi[v];
-		int armed = 0;
-
-		if (!pf->vsi[v] ||
-		    test_bit(__I40E_DOWN, &vsi->state) ||
-		    (vsi->netdev && !netif_carrier_ok(vsi->netdev)))
-			continue;
-
-		for (i = 0; i < vsi->num_queue_pairs; i++) {
-			set_check_for_tx_hang(vsi->tx_rings[i]);
-			if (test_bit(__I40E_HANG_CHECK_ARMED,
-				     &vsi->tx_rings[i]->state))
-				armed++;
-		}
-
-		if (armed) {
-			if (!(pf->flags & I40E_FLAG_MSIX_ENABLED)) {
-				wr32(&vsi->back->hw, I40E_PFINT_DYN_CTL0,
-				     (I40E_PFINT_DYN_CTL0_INTENA_MASK |
-				      I40E_PFINT_DYN_CTL0_SWINT_TRIG_MASK |
-				      I40E_PFINT_DYN_CTL0_ITR_INDX_MASK |
-				      I40E_PFINT_DYN_CTL0_SW_ITR_INDX_ENA_MASK |
-				      I40E_PFINT_DYN_CTL0_SW_ITR_INDX_MASK));
-			} else {
-				u16 vec = vsi->base_vector - 1;
-				u32 val = (I40E_PFINT_DYN_CTLN_INTENA_MASK |
-				      I40E_PFINT_DYN_CTLN_SWINT_TRIG_MASK |
-				      I40E_PFINT_DYN_CTLN_ITR_INDX_MASK |
-				      I40E_PFINT_DYN_CTLN_SW_ITR_INDX_ENA_MASK |
-				      I40E_PFINT_DYN_CTLN_SW_ITR_INDX_MASK);
-				for (i = 0; i < vsi->num_q_vectors; i++, vec++)
-					wr32(&vsi->back->hw,
-					     I40E_PFINT_DYN_CTLN(vec), val);
-			}
-			i40e_flush(&vsi->back->hw);
-		}
-	}
-}
-
-/**
  * i40e_watchdog_subtask - periodic checks not using event driven response
  * @pf: board private structure
  **/
@@ -5839,7 +5895,6 @@ static void i40e_watchdog_subtask(struct i40e_pf *pf)
 		return;
 	pf->service_timer_previous = jiffies;
 
-	i40e_check_hang_subtask(pf);
 	i40e_link_event(pf);
 
 	/* Update the stats for active netdevs so the network stack
@@ -6807,6 +6862,7 @@ static void i40e_service_task(struct work_struct *work)
 		return;
 	}
 
+	i40e_detect_recover_hung(pf);
 	i40e_reset_subtask(pf);
 	i40e_handle_mdd_event(pf);
 	i40e_vc_process_vflr_event(pf);
@@ -8770,7 +8826,7 @@ int i40e_vsi_release(struct i40e_vsi *vsi)
 	list_for_each_entry_safe(f, ftmp, &vsi->mac_filter_list, list)
 		i40e_del_filter(vsi, f->macaddr, f->vlan,
 				f->is_vf, f->is_netdev);
-	i40e_sync_vsi_filters(vsi);
+	i40e_sync_vsi_filters(vsi, false);
 
 	i40e_vsi_delete(vsi);
 	i40e_vsi_free_q_vectors(vsi);
@@ -10101,7 +10157,6 @@ static int i40e_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	INIT_WORK(&pf->service_task, i40e_service_task);
 	clear_bit(__I40E_SERVICE_SCHED, &pf->state);
 	pf->flags |= I40E_FLAG_NEED_LINK_UPDATE;
-	pf->link_check_timeout = jiffies;
 
 	/* WoL defaults to disabled */
 	pf->wol_en = false;