Le 01/02/2016 01:39, Florian Fainelli a écrit :
Le 31/01/2016 16:24, Eric Dumazet a écrit :
On Sun, 2016-01-31 at 13:37 -0800, Tom Herbert wrote:
Call get_unaligned_be32 when we access 32-bit fields in
__skb_flow_dissect. At the beginning check for unlikely case of
1-byte aligned packet.
Note that flow_dissector may be asked to parse packet unaligned
fields in two instances:
1) Packet from a driver which is aligned to Ethernet header
(2-byte alignment)
2) Parsing inner headers of a received GRE-TEB packet
Testing: Ran super_netperf tests did not see a regression. This was on
x86 which does not have problems with unaligned data.
But this test is absolutely useless, what about testing arches that
actually care ?
I am told all these MIPS based boxes have already not enough cpu power.
How about the Cavium OCTEON family and Broadcom/Netlogic XLR/XLP, those
are massively multi-core and MIPS64 capable, even though they may not
always run a Linux networking stack, some do.
There are also plenty of ARMv7/ARMv8 devices out there that would
benefit from proper alignment some might end-up using mlx4/5 and intel
cards.
There is also the tile architecture, up to 76 cores on the board I've seen. It
requires an alignment on 8!
I wonder how this case may be properly handled. A simple ipip scenario fails.
