diff options
| author |   Jesse Brandeburg <jesse.brandeburg@intel.com> | 2010-04-27 01:37:41 +0000 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2010-04-27 12:53:28 -0700 |
| commit | ef021194d262bdfa706dc5755596e252175a6bbc (patch) | |
| tree | 4c5b3febfe32226173d08572d95a41693bbca712 /drivers/net/ixgbe/ixgbe_main.c | |
| parent | ixgbe: enable extremely low latency (diff) | |
| download | linux-dev-ef021194d262bdfa706dc5755596e252175a6bbc.tar.xz linux-dev-ef021194d262bdfa706dc5755596e252175a6bbc.zip | |
ixgbe: fix bug when EITR=0 causing no writebacks
writebacks can be held indefinitely by hardware if EITR=0, when
combined with TXDCTL.WTHRESH=8. When EITR=0, WTHRESH should be
set back to zero.
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ixgbe/ixgbe_main.c')
| -rw-r--r-- | drivers/net/ixgbe/ixgbe_main.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/net/ixgbe/ixgbe_main.c b/drivers/net/ixgbe/ixgbe_main.c index 0c4ca6822b70..fe7e260e0157 100644 --- a/drivers/net/ixgbe/ixgbe_main.c +++ b/drivers/net/ixgbe/ixgbe_main.c @@ -2945,8 +2945,13 @@ static int ixgbe_up_complete(struct ixgbe_adapter *adapter) for (i = 0; i < adapter->num_tx_queues; i++) { j = adapter->tx_ring[i]->reg_idx; txdctl = IXGBE_READ_REG(hw, IXGBE_TXDCTL(j)); - /* enable WTHRESH=8 descriptors, to encourage burst writeback */ - txdctl |= (8 << 16); + if (adapter->rx_itr_setting == 0) { + /* cannot set wthresh when itr==0 */ + txdctl &= ~0x007F0000; + } else { + /* enable WTHRESH=8 descriptors, to encourage burst writeback */ + txdctl |= (8 << 16); + } IXGBE_WRITE_REG(hw, IXGBE_TXDCTL(j), txdctl); } |