xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

net: ipv4: Control SKB reprioritization after forwarding

Browse Source 
After IPv4 packets are forwarded, the priority of the corresponding SKB
is updated according to the TOS field of IPv4 header. This overrides any
prioritization done earlier by e.g. an skbedit action or ingress-qos-map
defined at a vlan device.

Such overriding may not always be desirable. Even if the packet ends up
being routed, which implies this is an L3 network node, an administrator
may wish to preserve whatever prioritization was done earlier on in the
pipeline.

Therefore introduce a sysctl that controls this behavior. Keep the
default value at 1 to maintain backward-compatible behavior.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Petr Machata
2018-08-01 00:36:03 +02:00
committed by David S. Miller
parent 83ba464515
commit 432e05d328
5 changed files with 22 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
Documentation/networking/ip-sysctl.txt
View File

@@ -81,6 +81,15 @@ fib_multipath_hash_policy - INTEGER
0 - Layer 3
1 - Layer 4
ip_forward_update_priority - INTEGER
Whether to update SKB priority from "TOS" field in IPv4 header after it
is forwarded. The new SKB priority is mapped from TOS field value
according to an rt_tos2priority table (see e.g. man tc-prio).
Default: 1 (Update priority.)
Possible values:
0 - Do not update priority.
1 - Update priority.
route/max_size - INTEGER
Maximum number of routes allowed in the kernel. Increase
this when using large numbers of interfaces and/or routes.