tree 1d779fe118898fa814d22b56fe734f19083e940a
parent b87d9f17b29f6fb3ec0645a84a1842718dcbf9a2
author Carmelo Cascone <carmelo@opennetworking.org> 1543141592 -0800
committer Carmelo Cascone <carmelo@opennetworking.org> 1544568486 -0800

Improve fabric.p4 to reduce pipeline resources and refactor pipeconf impl

This patch affects both the P4 pipeline implementation and the
Java pipeconf.

P4 PIPELINE
- Less tables and smarter use of metadata to reduce inter-tables
dependencies and favor parallel execution of tables.
- Removed unused actions / renamed existing ones to make forwarding
behavior clearer (e.g. ingress_port_vlan table)
- Remove co-existence of simple and hansed table. Hashed should be the
default one, but implementations that do not support action profiles
might compile fabric.p4 to use the simple one.
- Use @name annotations for match fields to make control plane
independent of table implementation.
- Use @hidden to avoid showing actions and table on the p4info that
cannot be controlled at runtime.
- First attempt to support double VLAN cross-connect (xconnect table).
- New design has been tested with "fabric-refactoring" branch of
fabric-p4test:
github.com/opennetworkinglab/fabric-p4test/tree/fabric-refactoring

JAVA PIPECONF
This patch brings a major refactoring that reflects the experience
gathered in the past months of working on fabric.p4 and reasoning on its
pipeconf implementation. Indeed, the FlowObjective API is
under-specified and sometimes ambiguous which makes the process of
creating and maintaining a pipeliner implementation tedious. This
refactoring brings a simplified implementation by removing unused/
unnecessary functionalities and by recognizing commonality when possible
(e.g. by means of abstract and utility classes). It also makes design
patterns more explicit and consistent. Overall, the goal is to reduce
technical debt and to make it easier to support new features as we
evolve fabric.p4

Changes include:
- Changes in pipeliner/interpreter to reflect new pipeline design.
- By default translate objective treatment to PiAction. This favors
debuggability of flow rules in ONOS.
- Support new NextObjective’s NextTreatment class.
- Remove lots of unused/unnecessary code (e.g. async callback handling
for pending objective install status in pipeliner as current
implementation was always returning success)
- Gather commonality in abstract classes and simplify implementation
for objective translator (filtering, forwarding, next)
- New implementation of ForwardingFunctionTypes (FFT) that looks at
criterion instance values along with their types (to avoid relying on
case-specific if-else conditions to recognize variants of an FFT)
- Adaptive translation of NextObjective based on presence of simple or
hashed table.
- Support DENY FilteringObjective

Also:
- Fix onos-p4-gen-constants to avoid generating conflicting
PiMatchFieldId variable names.
- Install Graphviz tools in p4vm to generate p4c graphs
- Generate p4c graphs by default when compiling fabric.p4
- Use more compact Hex string when printing PI values

Change-Id: Ife79e44054dc5bc48833f95d0551a7370150eac5