Based on the original patch submitted my Michael Wang
<wang...@linux.vnet.ibm.com>.
Descriptors may not be write-back while checking TX hang with flag
FLAG2_DMA_BURST on.
So when we detect hang, we just flush the descriptor and detect
again for once.
-v2 change 1 to true and 0 to false and remove extra ()
This patch is applicable to stable kernels 3.1 - 2.6.38. This
patch is already upstream in Linus's tree, see commit id
09357b00255c233705b1cf6d76a8d147340545b8. This is the backported
version of the patch for kernels 3.1 to 2.6.38 (due to the
drivers/net/ directory structure change in 3.2).
CC: Michael Wang <wang...@linux.vnet.ibm.com>
CC: Flavio Leitner <f...@redhat.com>
Acked-by: Jesse Brandeburg <jesse.brandeb...@intel.com>
Tested-by: Aaron Brown <aaron.f.br...@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirs...@intel.com>
---
drivers/net/e1000e/e1000.h | 1 +
drivers/net/e1000e/netdev.c | 23 ++++++++++++++++++++---
2 files changed, 21 insertions(+), 3 deletions(-)
diff --git a/drivers/net/e1000e/e1000.h b/drivers/net/e1000e/e1000.h
index 8533ad7..be2f25a 100644
--- a/drivers/net/e1000e/e1000.h
+++ b/drivers/net/e1000e/e1000.h
@@ -309,6 +309,7 @@ struct e1000_adapter {
u32 txd_cmd;
bool detect_tx_hung;
+ bool tx_hang_recheck;
u8 tx_timeout_factor;
u32 tx_int_delay;
diff --git a/drivers/net/e1000e/netdev.c b/drivers/net/e1000e/netdev.c
index 2198e61..125abed 100644
--- a/drivers/net/e1000e/netdev.c
+++ b/drivers/net/e1000e/netdev.c
@@ -1000,6 +1000,7 @@ static void e1000_print_hw_hang(struct work_struct *work)
struct e1000_adapter *adapter = container_of(work,
struct e1000_adapter,
print_hang_task);
+ struct net_device *netdev = adapter->netdev;
struct e1000_ring *tx_ring = adapter->tx_ring;
unsigned int i = tx_ring->next_to_clean;
unsigned int eop = tx_ring->buffer_info[i].next_to_watch;
@@ -1011,6 +1012,21 @@ static void e1000_print_hw_hang(struct work_struct *work)
if (test_bit(__E1000_DOWN, &adapter->state))
return;
+ if (!adapter->tx_hang_recheck &&
+ (adapter->flags2 & FLAG2_DMA_BURST)) {
+ /* May be block on write-back, flush and detect again
+ * flush pending descriptor writebacks to memory
+ */
+ ew32(TIDV, adapter->tx_int_delay | E1000_TIDV_FPD);
+ /* execute the writes immediately */
+ e1e_flush();
+ adapter->tx_hang_recheck = true;
+ return;
+ }
+ /* Real hang detected */
+ adapter->tx_hang_recheck = false;
+ netif_stop_queue(netdev);
+
e1e_rphy(hw, PHY_STATUS, &phy_status);
e1e_rphy(hw, PHY_1000T_STATUS, &phy_1000t_status);
e1e_rphy(hw, PHY_EXT_STATUS, &phy_ext_status);
@@ -1124,10 +1140,10 @@ static bool e1000_clean_tx_irq(struct e1000_adapter
*adapter)
if (tx_ring->buffer_info[i].time_stamp &&
time_after(jiffies, tx_ring->buffer_info[i].time_stamp
+ (adapter->tx_timeout_factor * HZ)) &&
- !(er32(STATUS) & E1000_STATUS_TXOFF)) {
+ !(er32(STATUS) & E1000_STATUS_TXOFF))
schedule_work(&adapter->print_hang_task);
- netif_stop_queue(netdev);
- }
+ else
+ adapter->tx_hang_recheck = false;
}
adapter->total_tx_bytes += total_tx_bytes;
adapter->total_tx_packets += total_tx_packets;
@@ -3753,6 +3769,7 @@ static int e1000_open(struct net_device *netdev)
e1000_irq_enable(adapter);
+ adapter->tx_hang_recheck = false;
netif_start_queue(netdev);
adapter->idle_check = true;
--
1.7.7.6
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
