The plug qdisc supports two operations - plug and unplug. When the
qdisc receives a plug ("buffer") command via netlink request,
packets arriving henceforth are buffered until a corresponding unplug
command is received. Depending on the type of unplug ("release_one"
or "release_indefinite"), the queue can be unplugged indefinitely or
selectively.
The plug qdisc allows a user to implement network output buffering
(aka output commit), used commonly in checkpoint based fault tolerance
systems. It also supports a general purpose queue plug/unplug
functionality.
The associated kernel module is available in David Miller's net-next
tree, commit: c3059be16c9ef29c05f0876a9df5fea21f29724f
This patch introduces userspace tools and API, to control the qdisc
via netlink messages.
Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
Signed-off-by: Thomas Graf <tgraf@redhat.com>
Finally got rid of all the qdisc/class/cls code duplication in
the tc module API. The API takes care of allocation/freeing the
tc object specific data.
I hope I got it right this time.
- Fixes a bunch of bugs related to ematches
- Adds support for the nbyte ematch
- Adds a bison/flex parser for ematch expressions, expressions
may look like this:
ip.length > 256 && pattern(ip6.src = 3ffe::/16)
documenation on syntax follows
- adds ematch support to the basic classifier (--ematch EXPR)
So far all common tc atttributes were accessed via specific functions, i.e.
rtnl_class_set_parent(), rtnl_qdisc_set_parent(), rtnl_cls_set_parent()
which implied a lot of code duplication. Since all tc objects are derived
from struct rtnl_tc and these common attributes are already stored in there
this patch removes all type specific functions and makes rtnl_tc_* attribute
functions public.
rtnl_qdisc_set_parent(qdisc, 10);
becomes:
rtnl_tc_set_parent((struct rtnl_tc *) qdisc, 10);
This patch also adds the following new attributes to tc objects therefore
removing them as tc specific attributes:
- mtu
- mpu
- overhead
This allows for the rate table calculations to be unified as well taking into
account the new kernel behavior to take care of overhead automatically.
Adds a cli based tool to add/update traffic classes. This tool requires
each class to be supported via the respetive qdisc module in
pkglibdir/cli/qdisc/$name.so.
Syntax:
nl-class-add --dev eth2 --parent 1: --id 1:1 htb --rate 100mbit
nl-class-add --update --dev eth2 --id 1:1 htb --rate 200mbit
Adds a cli based tool to add/update/replace qdiscs. This tool requires
each qdisc to be supported via a dynamic loadable module in
pkglibdir/cli/qdisc/$name.so.
So far HTB and blackhole have been implemented.
Syntax:
nl-qdisc-add --dev eth2 --parent root --id 1: htb --r2q=5
nl-qdisc-add --update-only --dev eth2 --id 1: htb --r2q=10
Shriram Rajagopalan