linux/drivers/net/ethernet/intel
Jason Wang f663dd9aaf net: core: explicitly select a txq before doing l2 forwarding
Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The
will cause several issues:

- NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan
  instead of lower device which misses the necessary txq synchronization for
  lower device such as txq stopping or frozen required by dev watchdog or
  control path.
- dev_hard_start_xmit() was called with NULL txq which bypasses the net device
  watchdog.
- dev_hard_start_xmit() does not check txq everywhere which will lead a crash
  when tso is disabled for lower device.

Fix this by explicitly introducing a new param for .ndo_select_queue() for just
selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also
extended to accept this parameter and dev_queue_xmit_accel() was used to do l2
forwarding transmission.

With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need
to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep
a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of
dev_queue_xmit() to do the transmission.

In the future, it was also required for macvtap l2 forwarding support since it
provides a necessary synchronization method.

Cc: John Fastabend <john.r.fastabend@intel.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: e1000-devel@lists.sourceforge.net
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 13:23:08 -05:00
..
e1000 e1000: fix possible reset_task running after adapter down 2013-11-30 00:02:12 -08:00
e1000e e1000e: Fix a compile flag mis-match for suspend/resume 2013-12-17 22:45:03 -08:00
i40e i40e: fix null dereference 2013-12-14 22:59:41 -05:00
igb igb: Fix for issue where values could be too high for udelay function. 2013-12-14 22:59:42 -05:00
igbvf Merge branch 'for-linus-dma-masks' of git://git.linaro.org/people/rmk/linux-arm 2013-11-14 07:55:21 +09:00
ixgb Merge branch 'for-linus-dma-masks' of git://git.linaro.org/people/rmk/linux-arm 2013-11-14 07:55:21 +09:00
ixgbe net: core: explicitly select a txq before doing l2 forwarding 2014-01-10 13:23:08 -05:00
ixgbevf Merge branch 'for-linus-dma-masks' of git://git.linaro.org/people/rmk/linux-arm 2013-11-14 07:55:21 +09:00
Kconfig i40e: include i40e in kernel proper 2013-09-11 02:28:40 -07:00
Makefile i40e: include i40e in kernel proper 2013-09-11 02:28:40 -07:00
e100.c net: e100: remove unnecessary pci_set_drvdata() 2013-10-21 17:21:01 -04:00