2009-04-17 23:04:42

by Divy Le ray

Subject: [PATCH 2.6.30 1/4] cxgb3: fix link fault handling

From: Divy Le Ray <[email protected]>

Use the existing periodic task to handle link faults.
The link fault interrupt handler is also called in work queue context,
which is wrong and might cause potential deadlocks.

Signed-off-by: Divy Le Ray <[email protected]>
---

drivers/net/cxgb3/cxgb3_main.c | 22 ++--------------------
drivers/net/cxgb3/t3_hw.c | 11 +----------
2 files changed, 3 insertions(+), 30 deletions(-)

diff --git a/drivers/net/cxgb3/cxgb3_main.c b/drivers/net/cxgb3/cxgb3_main.c
index ab0e5fe..9fdfe0b 100644
--- a/drivers/net/cxgb3/cxgb3_main.c
+++ b/drivers/net/cxgb3/cxgb3_main.c
@@ -2493,6 +2493,7 @@ static void check_link_status(struct adapter *adapter)

spin_lock_irq(&adapter->work_lock);
if (p->link_fault) {
+ t3_link_fault(adapter, i);
spin_unlock_irq(&adapter->work_lock);
continue;
}
@@ -2554,9 +2555,7 @@ static void t3_adap_check_task(struct work_struct *work)

adapter->check_task_cnt++;

- /* Check link status for PHYs without interrupts */
- if (p->linkpoll_period)
- check_link_status(adapter);
+ check_link_status(adapter);

/* Accumulate MAC stats if needed */
if (!p->linkpoll_period ||
@@ -2680,21 +2679,6 @@ void t3_os_ext_intr_handler(struct adapter *adapter)
spin_unlock(&adapter->work_lock);
}

-static void link_fault_task(struct work_struct *work)
-{
- struct adapter *adapter = container_of(work, struct adapter,
- link_fault_handler_task);
- int i;
-
- for_each_port(adapter, i) {
- struct net_device *netdev = adapter->port[i];
- struct port_info *pi = netdev_priv(netdev);
-
- if (pi->link_fault)
- t3_link_fault(adapter, i);
- }
-}
-
void t3_os_link_fault_handler(struct adapter *adapter, int port_id)
{
struct net_device *netdev = adapter->port[port_id];
@@ -2702,7 +2686,6 @@ void t3_os_link_fault_handler(struct adapter *adapter, int port_id)

spin_lock(&adapter->work_lock);
pi->link_fault = 1;
- queue_work(cxgb3_wq, &adapter->link_fault_handler_task);
spin_unlock(&adapter->work_lock);
}

@@ -3082,7 +3065,6 @@ static int __devinit init_one(struct pci_dev *pdev,

INIT_LIST_HEAD(&adapter->adapter_list);
INIT_WORK(&adapter->ext_intr_handler_task, ext_intr_task);
- INIT_WORK(&adapter->link_fault_handler_task, link_fault_task);
INIT_WORK(&adapter->fatal_error_handler_task, fatal_error_task);
INIT_DELAYED_WORK(&adapter->adap_check_task, t3_adap_check_task);

diff --git a/drivers/net/cxgb3/t3_hw.c b/drivers/net/cxgb3/t3_hw.c
index 31ed31a..e1bd690 100644
--- a/drivers/net/cxgb3/t3_hw.c
+++ b/drivers/net/cxgb3/t3_hw.c
@@ -1202,7 +1202,6 @@ void t3_link_changed(struct adapter *adapter, int port_id)
struct cphy *phy = &pi->phy;
struct cmac *mac = &pi->mac;
struct link_config *lc = &pi->link_config;
- int force_link_down = 0;

phy->ops->get_link_status(phy, &link_ok, &speed, &duplex, &fc);

@@ -1218,14 +1217,9 @@ void t3_link_changed(struct adapter *adapter, int port_id)
status = t3_read_reg(adapter, A_XGM_INT_STATUS + mac->offset);
if (status & F_LINKFAULTCHANGE) {
mac->stats.link_faults++;
- force_link_down = 1;
+ pi->link_fault = 1;
}
t3_open_rx_traffic(mac, rx_cfg, rx_hash_high, rx_hash_low);
-
- if (force_link_down) {
- t3_os_link_fault_handler(adapter, port_id);
- return;
- }
}

if (lc->requested_fc & PAUSE_AUTONEG)
@@ -1292,9 +1286,6 @@ void t3_link_fault(struct adapter *adapter, int port_id)
/* Account link faults only when the phy reports a link up */
if (link_ok)
mac->stats.link_faults++;
-
- msleep(1000);
- t3_os_link_fault_handler(adapter, port_id);
} else {
if (link_ok)
t3_write_reg(adapter, A_XGM_XAUI_ACT_CTRL + mac->offset,

2009-04-20 09:08:36

by David Miller

Subject: Re: [PATCH 2.6.30 1/4] cxgb3: fix link fault handling

From: Divy Le Ray <[email protected]>
Date: Fri, 17 Apr 2009 15:21:11 -0700

> Use the existing periodic task to handle link faults.
> The link fault interrupt handler is also called in work queue context,
> which is wrong and might cause potential deadlocks.
>
> Signed-off-by: Divy Le Ray <[email protected]>

Applied.