linux/include
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
..
acpi Merge branches 'acpi-pci-pm' and 'acpi-pci-hotplug' 2013-12-31 22:03:37 +01:00
asm-generic mm: Fix NULL pointer dereference in madvise(MADV_WILLNEED) support 2013-12-20 12:17:03 -08:00
clocksource
crypto crypto: scatterwalk - Use sg_chain_ptr on chain entries 2013-12-09 19:58:52 +08:00
drm drm/radeon: 0x9649 is SUMO2 not SUMO 2013-12-23 10:03:41 -05:00
dt-bindings For the 3.13 merge window we have a couple of new drivers for the AMS 2013-11-15 16:37:40 -08:00
keys
kvm
linux net: core: explicitly select a txq before doing l2 forwarding 2014-01-10 13:23:08 -05:00
math-emu
media [media] videobuf2: Add support for file access mode flags for DMABUF exporting 2013-12-09 14:50:50 -02:00
memory
misc
net sctp: Remove outqueue empty state 2014-01-02 17:22:48 -05:00
pcmcia
ras
rdma IB/core: const'ify inbuf in struct ib_udata 2013-12-16 10:38:28 -08:00
rxrpc
scsi [SCSI] Disable WRITE SAME for RAID and virtual host adapter drivers 2013-11-29 08:48:39 +04:00
sound ALSA: memalloc.h - fix wrong truncation of dma_addr_t 2013-12-10 15:30:46 +01:00
target target/file: Update hw_max_sectors based on current block_size 2013-12-19 00:18:54 -08:00
trace Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-12-02 10:13:09 -08:00
uapi Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux 2014-01-01 11:36:16 -08:00
video fbdev changes for 3.13 2013-11-14 14:44:20 +09:00
xen Bug-fixes: 2013-12-20 09:34:54 -08:00
Kbuild