To allow configuring user-defined actions as a result of inner workings of
a qdisc, a concept of qevents was recently introduced to the kernel.
Qevents are attach points for TC blocks, where filters can be put that are
executed as the packet hits well-defined points in the qdisc algorithms.
The attached blocks can be shared, in a manner similar to clsact ingress
and egress blocks, arbitrary classifiers with arbitrary actions can be put
on them, etc.
For example:
# tc qdisc add dev eth0 root handle 1: \
red limit 500K avpkt 1K qevent early_drop block 10
# tc filter add block 10 \
matchall action mirred egress mirror dev eth1
This patch set introduces the corresponding iproute2 support. Patch #1 adds
the new netlink attribute enumerators. Patch #2 adds a set of helpers to
implement qevents, and #3 adds a generic documentation to tc.8. Patch #4
then adds two new qevents to the RED qdisc: mark and early_drop.
Changes from v1 to v2:
- Patch #3:
- s/early/early_drop/ in the example.
Changes from RFC to v1:
- Rename "tail" qevent to "tail_drop".
- Adapt to the new 100-column standard.
- Add a selftest
Petr Machata (4):
uapi: pkt_sched: Add two new RED attributes
tc: Add helpers to support qevent handling
man: tc: Describe qevents
tc: q_red: Add support for qevents "mark" and "early_drop"
include/uapi/linux/pkt_sched.h | 2 +
man/man8/tc-red.8 | 18 ++-
man/man8/tc.8 | 19 ++++
tc/Makefile | 1 +
tc/q_red.c | 30 ++++-
tc/tc_qevent.c | 202 +++++++++++++++++++++++++++++++++
tc/tc_qevent.h | 49 ++++++++
7 files changed, 317 insertions(+), 4 deletions(-)
create mode 100644 tc/tc_qevent.c
create mode 100644 tc/tc_qevent.h
--
2.20.1
