qla3xxx: bugfix: Move link state machine into a worker thread

The link state machine requires access to some resources that
are shared with the iSCSI function on the chip.  (See iSCSI
driver at drivers/scsi/qla4xxx)  If the interface is being
up/downed at a rapid pace this driver may need to sleep
waiting to get access to the common resources. For this we
are moving the state machine to run as a work thread.

Signed-off-by: Ron Mercer <ron.mercer@qlogic.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 13 insertions, 14 deletions

diff --git a/drivers/net/qla3xxx.c b/drivers/net/qla3xxx.c
index 30adf726743c..4f0fd41dce19 100644
--- a/drivers/net/qla3xxx.c
+++ b/drivers/net/qla3xxx.c
@@ -1645,8 +1645,11 @@ static int ql_finish_auto_neg(struct ql3_adapter *qdev)
         return 0;
 }
 
-static void ql_link_state_machine(struct ql3_adapter *qdev)
+static void ql_link_state_machine_work(struct work_struct *work)
 {
+        struct ql3_adapter *qdev =
+                container_of(work, struct ql3_adapter, link_state_work.work);
+
         u32 curr_link_state;
         unsigned long hw_flags;
 
@@ -1661,6 +1664,10 @@ static void ql_link_state_machine(struct ql3_adapter *qdev)
                                "state.\n", qdev->ndev->name);
 
                 spin_unlock_irqrestore(&qdev->hw_lock, hw_flags);
+
+                /* Restart timer on 2 second interval. */
+                mod_timer(&qdev->adapter_timer, jiffies + HZ * 1);\
+
                 return;
         }
 
@@ -1705,6 +1712,9 @@ static void ql_link_state_machine(struct ql3_adapter *qdev)
                 break;
         }
         spin_unlock_irqrestore(&qdev->hw_lock, hw_flags);
+
+        /* Restart timer on 2 second interval. */
+        mod_timer(&qdev->adapter_timer, jiffies + HZ * 1);
 }
 
 /*
@@ -3941,19 +3951,7 @@ static void ql_get_board_info(struct ql3_adapter *qdev)
 static void ql3xxx_timer(unsigned long ptr)
 {
         struct ql3_adapter *qdev = (struct ql3_adapter *)ptr;
-
-        if (test_bit(QL_RESET_ACTIVE,&qdev->flags)) {
-                printk(KERN_DEBUG PFX
-                       "%s: Reset in progress.\n",
-                       qdev->ndev->name);
-                goto end;
-        }
-
-        ql_link_state_machine(qdev);
-
-        /* Restart timer on 2 second interval. */
-end:
-        mod_timer(&qdev->adapter_timer, jiffies + HZ * 1);
+        queue_delayed_work(qdev->workqueue, &qdev->link_state_work, 0);
 }
 
 static int __devinit ql3xxx_probe(struct pci_dev *pdev,
@@ -4103,6 +4101,7 @@ static int __devinit ql3xxx_probe(struct pci_dev *pdev,
         qdev->workqueue = create_singlethread_workqueue(ndev->name);
         INIT_DELAYED_WORK(&qdev->reset_work, ql_reset_work);
         INIT_DELAYED_WORK(&qdev->tx_timeout_work, ql_tx_timeout_work);
+        INIT_DELAYED_WORK(&qdev->link_state_work, ql_link_state_machine_work);
 
         init_timer(&qdev->adapter_timer);
         qdev->adapter_timer.function = ql3xxx_timer;