ixgbe: Update watchdog thread to accomodate longerlink_up events

This patch updates the link_up code and watchdog thread so that link_up
doesn't cause stack overflows due to long waits in interrupt context.

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

diff --git a/drivers/net/ixgbe/ixgbe.h b/drivers/net/ixgbe/ixgbe.h
index 90b5383..2b827a6 100644 (file)
--- a/drivers/net/ixgbe/ixgbe.h
+++ b/drivers/net/ixgbe/ixgbe.h
@@ -309,6 +309,12 @@ struct ixgbe_adapter {
        u64 lro_aggregated;
        u64 lro_flushed;
        u64 lro_no_desc;
+
+       u32 link_speed;
+       bool link_up;
+       unsigned long link_check_timeout;
+
+       struct work_struct watchdog_task;
 };
 
 enum ixbge_state_t {

diff --git a/drivers/net/ixgbe/ixgbe_82598.c b/drivers/net/ixgbe/ixgbe_82598.c
index ba09063..1e014bc 100644 (file)
--- a/drivers/net/ixgbe/ixgbe_82598.c
+++ b/drivers/net/ixgbe/ixgbe_82598.c
@@ -47,7 +47,8 @@ static s32 ixgbe_get_copper_link_settings_82598(struct ixgbe_hw *hw,
 static enum ixgbe_media_type ixgbe_get_media_type_82598(struct ixgbe_hw *hw);
 static s32 ixgbe_setup_mac_link_82598(struct ixgbe_hw *hw);
 static s32 ixgbe_check_mac_link_82598(struct ixgbe_hw *hw, u32 *speed,
-                                     bool *link_up);
+                                      bool *link_up,
+                                      bool link_up_wait_to_complete);
 static s32 ixgbe_setup_mac_link_speed_82598(struct ixgbe_hw *hw, u32 speed,
                                            bool autoneg,
                                            bool autoneg_wait_to_complete);
@@ -277,20 +278,36 @@ static s32 ixgbe_setup_mac_link_82598(struct ixgbe_hw *hw)
  *  @hw: pointer to hardware structure
  *  @speed: pointer to link speed
  *  @link_up: true is link is up, false otherwise
+ *  @link_up_wait_to_complete: bool used to wait for link up or not
  *
  *  Reads the links register to determine if link is up and the current speed
  **/
 static s32 ixgbe_check_mac_link_82598(struct ixgbe_hw *hw, u32 *speed,
-                                     bool *link_up)
+                                      bool *link_up,
+                                      bool link_up_wait_to_complete)
 {
        u32 links_reg;
+       u32 i;
 
        links_reg = IXGBE_READ_REG(hw, IXGBE_LINKS);
 
-       if (links_reg & IXGBE_LINKS_UP)
-               *link_up = true;
-       else
-               *link_up = false;
+       if (link_up_wait_to_complete) {
+               for (i = 0; i < IXGBE_LINK_UP_TIME; i++) {
+                       if (links_reg & IXGBE_LINKS_UP) {
+                               *link_up = true;
+                               break;
+                       } else {
+                               *link_up = false;
+                       }
+                       msleep(100);
+                       links_reg = IXGBE_READ_REG(hw, IXGBE_LINKS);
+               }
+       } else {
+               if (links_reg & IXGBE_LINKS_UP)
+                       *link_up = true;
+               else
+                       *link_up = false;
+       }
 
        if (links_reg & IXGBE_LINKS_SPEED)
                *speed = IXGBE_LINK_SPEED_10GB_FULL;

diff --git a/drivers/net/ixgbe/ixgbe_ethtool.c b/drivers/net/ixgbe/ixgbe_ethtool.c
index 61c000e..8f0e3f9 100644 (file)
--- a/drivers/net/ixgbe/ixgbe_ethtool.c
+++ b/drivers/net/ixgbe/ixgbe_ethtool.c
@@ -130,7 +130,7 @@ static int ixgbe_get_settings(struct net_device *netdev,
                ecmd->port = PORT_FIBRE;
        }
 
-       adapter->hw.mac.ops.check_link(hw, &(link_speed), &link_up);
+       adapter->hw.mac.ops.check_link(hw, &(link_speed), &link_up, false);
        if (link_up) {
                ecmd->speed = (link_speed == IXGBE_LINK_SPEED_10GB_FULL) ?
                                SPEED_10000 : SPEED_1000;

diff --git a/drivers/net/ixgbe/ixgbe_main.c b/drivers/net/ixgbe/ixgbe_main.c
index 9048195..036393e 100644 (file)
--- a/drivers/net/ixgbe/ixgbe_main.c
+++ b/drivers/net/ixgbe/ixgbe_main.c
@@ -902,6 +902,20 @@ static void ixgbe_set_itr_msix(struct ixgbe_q_vector *q_vector)
        return;
 }
 
+
+static void ixgbe_check_lsc(struct ixgbe_adapter *adapter)
+{
+       struct ixgbe_hw *hw = &adapter->hw;
+
+       adapter->lsc_int++;
+       adapter->flags |= IXGBE_FLAG_NEED_LINK_UPDATE;
+       adapter->link_check_timeout = jiffies;
+       if (!test_bit(__IXGBE_DOWN, &adapter->state)) {
+               IXGBE_WRITE_REG(hw, IXGBE_EIMC, IXGBE_EIMC_LSC);
+               schedule_work(&adapter->watchdog_task);
+       }
+}
+
 static irqreturn_t ixgbe_msix_lsc(int irq, void *data)
 {
        struct net_device *netdev = data;
@@ -909,11 +923,8 @@ static irqreturn_t ixgbe_msix_lsc(int irq, void *data)
        struct ixgbe_hw *hw = &adapter->hw;
        u32 eicr = IXGBE_READ_REG(hw, IXGBE_EICR);
 
-       if (eicr & IXGBE_EICR_LSC) {
-               adapter->lsc_int++;
-               if (!test_bit(__IXGBE_DOWN, &adapter->state))
-                       mod_timer(&adapter->watchdog_timer, jiffies);
-       }
+       if (eicr & IXGBE_EICR_LSC)
+               ixgbe_check_lsc(adapter);
 
        if (!test_bit(__IXGBE_DOWN, &adapter->state))
                IXGBE_WRITE_REG(hw, IXGBE_EIMS, IXGBE_EIMS_OTHER);
@@ -1237,12 +1248,8 @@ static irqreturn_t ixgbe_intr(int irq, void *data)
        if (!eicr)
                return IRQ_NONE;        /* Not our interrupt */
 
-       if (eicr & IXGBE_EICR_LSC) {
-               adapter->lsc_int++;
-               if (!test_bit(__IXGBE_DOWN, &adapter->state))
-                       mod_timer(&adapter->watchdog_timer, jiffies);
-       }
-
+       if (eicr & IXGBE_EICR_LSC)
+               ixgbe_check_lsc(adapter);
 
        if (netif_rx_schedule_prep(netdev, &adapter->q_vector[0].napi)) {
                adapter->tx_ring[0].total_packets = 0;
@@ -1897,6 +1904,8 @@ static int ixgbe_up_complete(struct ixgbe_adapter *adapter)
 
        /* bring the link up in the watchdog, this could race with our first
         * link up interrupt but shouldn't be a problem */
+       adapter->flags |= IXGBE_FLAG_NEED_LINK_UPDATE;
+       adapter->link_check_timeout = jiffies;
        mod_timer(&adapter->watchdog_timer, jiffies);
        return 0;
 }
@@ -2098,6 +2107,7 @@ void ixgbe_down(struct ixgbe_adapter *adapter)
 
        ixgbe_napi_disable_all(adapter);
        del_timer_sync(&adapter->watchdog_timer);
+       cancel_work_sync(&adapter->watchdog_task);
 
        netif_carrier_off(netdev);
        netif_tx_stop_all_queues(netdev);
@@ -3010,27 +3020,74 @@ void ixgbe_update_stats(struct ixgbe_adapter *adapter)
 static void ixgbe_watchdog(unsigned long data)
 {
        struct ixgbe_adapter *adapter = (struct ixgbe_adapter *)data;
-       struct net_device *netdev = adapter->netdev;
-       bool link_up;
-       u32 link_speed = 0;
+       struct ixgbe_hw *hw = &adapter->hw;
+
+       /* Do the watchdog outside of interrupt context due to the lovely
+        * delays that some of the newer hardware requires */
+       if (!test_bit(__IXGBE_DOWN, &adapter->state)) {
+               /* Cause software interrupt to ensure rx rings are cleaned */
+               if (adapter->flags & IXGBE_FLAG_MSIX_ENABLED) {
+                       u32 eics =
+                        (1 << (adapter->num_msix_vectors - NON_Q_VECTORS)) - 1;
+                       IXGBE_WRITE_REG(hw, IXGBE_EICS, eics);
+               } else {
+                       /* For legacy and MSI interrupts don't set any bits that
+                        * are enabled for EIAM, because this operation would
+                        * set *both* EIMS and EICS for any bit in EIAM */
+                       IXGBE_WRITE_REG(hw, IXGBE_EICS,
+                                    (IXGBE_EICS_TCP_TIMER | IXGBE_EICS_OTHER));
+               }
+               /* Reset the timer */
+               mod_timer(&adapter->watchdog_timer,
+                         round_jiffies(jiffies + 2 * HZ));
+       }
 
-       adapter->hw.mac.ops.check_link(&adapter->hw, &(link_speed), &link_up);
+       schedule_work(&adapter->watchdog_task);
+}
+
+/**
+ *  ixgbe_watchdog_task - worker thread to bring link up
+ *  @work: pointer to work_struct containing our data
+ **/
+static void ixgbe_watchdog_task(struct work_struct *work)
+{
+       struct ixgbe_adapter *adapter = container_of(work,
+                                                    struct ixgbe_adapter,
+                                                    watchdog_task);
+       struct net_device *netdev = adapter->netdev;
+       struct ixgbe_hw *hw = &adapter->hw;
+       u32 link_speed = adapter->link_speed;
+       bool link_up = adapter->link_up;
+
+       adapter->flags |= IXGBE_FLAG_IN_WATCHDOG_TASK;
+
+       if (adapter->flags & IXGBE_FLAG_NEED_LINK_UPDATE) {
+               hw->mac.ops.check_link(hw, &link_speed, &link_up, false);
+               if (link_up ||
+                   time_after(jiffies, (adapter->link_check_timeout +
+                                        IXGBE_TRY_LINK_TIMEOUT))) {
+                       IXGBE_WRITE_REG(hw, IXGBE_EIMS, IXGBE_EIMC_LSC);
+                       adapter->flags &= ~IXGBE_FLAG_NEED_LINK_UPDATE;
+               }
+               adapter->link_up = link_up;
+               adapter->link_speed = link_speed;
+       }
 
        if (link_up) {
                if (!netif_carrier_ok(netdev)) {
-                       u32 frctl = IXGBE_READ_REG(&adapter->hw, IXGBE_FCTRL);
-                       u32 rmcs = IXGBE_READ_REG(&adapter->hw, IXGBE_RMCS);
+                       u32 frctl = IXGBE_READ_REG(hw, IXGBE_FCTRL);
+                       u32 rmcs = IXGBE_READ_REG(hw, IXGBE_RMCS);
 #define FLOW_RX (frctl & IXGBE_FCTRL_RFCE)
 #define FLOW_TX (rmcs & IXGBE_RMCS_TFCE_802_3X)
                        DPRINTK(LINK, INFO, "NIC Link is Up %s, "
-                               "Flow Control: %s\n",
-                               (link_speed == IXGBE_LINK_SPEED_10GB_FULL ?
-                                "10 Gbps" :
-                                (link_speed == IXGBE_LINK_SPEED_1GB_FULL ?
-                                 "1 Gbps" : "unknown speed")),
-                               ((FLOW_RX && FLOW_TX) ? "RX/TX" :
-                                (FLOW_RX ? "RX" :
-                                (FLOW_TX ? "TX" : "None"))));
+                               "Flow Control: %s\n",
+                               (link_speed == IXGBE_LINK_SPEED_10GB_FULL ?
+                                "10 Gbps" :
+                                (link_speed == IXGBE_LINK_SPEED_1GB_FULL ?
+                                 "1 Gbps" : "unknown speed")),
+                               ((FLOW_RX && FLOW_TX) ? "RX/TX" :
+                                (FLOW_RX ? "RX" :
+                                (FLOW_TX ? "TX" : "None"))));
 
                        netif_carrier_on(netdev);
                        netif_tx_wake_all_queues(netdev);
@@ -3039,6 +3096,8 @@ static void ixgbe_watchdog(unsigned long data)
                        adapter->detect_tx_hung = true;
                }
        } else {
+               adapter->link_up = false;
+               adapter->link_speed = 0;
                if (netif_carrier_ok(netdev)) {
                        DPRINTK(LINK, INFO, "NIC Link is Down\n");
                        netif_carrier_off(netdev);
@@ -3047,24 +3106,7 @@ static void ixgbe_watchdog(unsigned long data)
        }
 
        ixgbe_update_stats(adapter);
-
-       if (!test_bit(__IXGBE_DOWN, &adapter->state)) {
-               /* Cause software interrupt to ensure rx rings are cleaned */
-               if (adapter->flags & IXGBE_FLAG_MSIX_ENABLED) {
-                       u32 eics =
-                        (1 << (adapter->num_msix_vectors - NON_Q_VECTORS)) - 1;
-                       IXGBE_WRITE_REG(&adapter->hw, IXGBE_EICS, eics);
-               } else {
-                       /* for legacy and MSI interrupts don't set any bits that
-                        * are enabled for EIAM, because this operation would
-                        * set *both* EIMS and EICS for any bit in EIAM */
-                       IXGBE_WRITE_REG(&adapter->hw, IXGBE_EICS,
-                                    (IXGBE_EICS_TCP_TIMER | IXGBE_EICS_OTHER));
-               }
-               /* Reset the timer */
-               mod_timer(&adapter->watchdog_timer,
-                         round_jiffies(jiffies + 2 * HZ));
-       }
+       adapter->flags &= ~IXGBE_FLAG_IN_WATCHDOG_TASK;
 }
 
 static int ixgbe_tso(struct ixgbe_adapter *adapter,
@@ -3707,6 +3749,7 @@ static int __devinit ixgbe_probe(struct pci_dev *pdev,
        adapter->watchdog_timer.data = (unsigned long)adapter;
 
        INIT_WORK(&adapter->reset_task, ixgbe_reset_task);
+       INIT_WORK(&adapter->watchdog_task, ixgbe_watchdog_task);
 
        err = ixgbe_init_interrupt_scheme(adapter);
        if (err)

diff --git a/drivers/net/ixgbe/ixgbe_type.h b/drivers/net/ixgbe/ixgbe_type.h
index 3e9c483..172f766 100644 (file)
--- a/drivers/net/ixgbe/ixgbe_type.h
+++ b/drivers/net/ixgbe/ixgbe_type.h
@@ -703,6 +703,7 @@
 #define IXGBE_LINKS_TL_FAULT    0x00001000
 #define IXGBE_LINKS_SIGNAL      0x00000F00
 
+#define IXGBE_LINK_UP_TIME      90 /* 9.0 Seconds */
 #define IXGBE_AUTO_NEG_TIME     45 /* 4.5 Seconds */
 
 /* SW Semaphore Register bitmasks */
@@ -1249,7 +1250,7 @@ struct ixgbe_mac_operations {
        s32 (*reset)(struct ixgbe_hw *);
        enum ixgbe_media_type (*get_media_type)(struct ixgbe_hw *);
        s32 (*setup_link)(struct ixgbe_hw *);
-       s32 (*check_link)(struct ixgbe_hw *, u32 *, bool *);
+       s32 (*check_link)(struct ixgbe_hw *, u32 *, bool *, bool);
        s32 (*setup_link_speed)(struct ixgbe_hw *, u32, bool, bool);
        s32 (*get_link_settings)(struct ixgbe_hw *, u32 *, bool *);
 };