[PATCH v8 00/17] graph enhancement for multi-core dispatch

[Zhirun Yan <zhirun.yan@intel.com>]

V8:
No performance dorp for original l3fwd-graph and graph_perf_autotest.

Update graph model set/get functions and add graph_model_is_valid() in patch 04.
Update doc for new scheme usage(choose model in runtime or compile time).
Update dispatch schedule struct into union.
Change enum rte_graph_worker_model to macro define in rte_graph_worker_common.h.
Add model clone in graph_clone() in patch 08.
Remove unnecessary inline for slow path func graph_src_node_avail() in patch 06.


V7:
Revert rte_rdtsc_precise() in fastpath to fix performance issues in patch 03.
Introduce new scheme for model choosing. Use RTE_GRAPH_MODEL_SELECT to choose in
  compile-time in patch 13, 15.(must have rte_graph_worker_model_set() to help
  other config func to do model specific things like alloc wq, collect stats)
Extract the common func clone_name() into graph_private.h for graph/node clone in
  patch 07.(new patch)
Use rte_graph->model in rte_graph_worker_model_set() instead of RTE_PER_LCORE_*.
Add test case for all new APIs in patch 16(new patch).
Remove *_END line in enum rte_graph_worker_model in patch 04.
Add model check for graph lcore binding.
Rename workqueue as graph_mcore_dispatch_wq_node in patch 09.
Change all new model files/APIs with prefix _mcore_dispatch_.
Change description of new API, comments of func/structure to explicitly mention for
  mcore dispatch model only. Add Doxygen comments.
Update l3fwd-graph with new scheme, Update doc.
Update MAINTAINERS.
Fix typo and format issues.

V6:
Change rte_rdtsc() to rte_rdtsc_precise().
Add union in rte_graph_param to configure models.
Remove memset in fastpath, add RTE_ASSERT for cloned graph.
Update copyright in patch 02.
Update l3fwd-graph node affinity, start from rx core successively.

V5:
Fix CI build issues about dynamically update doc.

V4:
Fix CI build issues about undefined reference of sched apis.
Remove inline for model setting.

V3:
Fix CI build issues about TLS and typo.

V2:
Use git mv to keep git history.
Use TLS for per-thread local storage.
Change model name to mcore dispatch.
Change API with specific mode name.
Split big patch.
Fix CI issues.
Rebase l3fwd-graph example.
Update doc and maintainers files.


Currently, rte_graph supports RTC (Run-To-Completion) model within each
of a single core.
RTC is one of the typical model of packet processing. Others like
Pipeline or Hybrid are lack of support.

The patch set introduces a 'multicore dispatch' model selection which
is a self-reacting scheme according to the core affinity.
The new model enables a cross-core dispatching mechanism which employs a
scheduling work-queue to dispatch streams to other worker cores which
being associated with the destination node. When core flavor of the
destination node is a default 'current', the stream can be continue
executed as normal.

Example:
3-node graph targets 3-core budget

RTC:
Graph: node-0 -> node-1 -> node-2 @Core0.

+ - - - - - - - - - - - - - - - - - - - - - +
'                Core #0/1/2                '
'                                           '
' +--------+     +---------+     +--------+ '
' | Node-0 | --> | Node-1  | --> | Node-2 | '
' +--------+     +---------+     +--------+ '
'                                           '
+ - - - - - - - - - - - - - - - - - - - - - +

Dispatch:

Graph topo: node-0 -> Core1; node-1 -> node-2; node-2 -> node-3.
Config graph: node-0 @Core0; node-1/3 @Core1; node-2 @Core2.

.. code-block:: diff

    + - - - - - -+     +- - - - - - - - - - - - - +     + - - - - - -+
    '  Core #0   '     '          Core #1         '     '  Core #2   '
    '            '     '                          '     '            '
    ' +--------+ '     ' +--------+    +--------+ '     ' +--------+ '
    ' | Node-0 | - - - ->| Node-1 |    | Node-3 |<- - - - | Node-2 | '
    ' +--------+ '     ' +--------+    +--------+ '     ' +--------+ '
    '            '     '     |                    '     '      ^     '
    + - - - - - -+     +- - -|- - - - - - - - - - +     + - - -|- - -+
                             |                                 |
                             + - - - - - - - - - - - - - - - - +


The patch set has been break down as below:

1. Split graph worker into common and default model part.
2. Inline graph node processing to make it reusable.
3. Add set/get APIs to choose worker model.
4. Introduce core affinity API to set the node run on specific worker core.
  (only use in new model)
5. Introduce graph affinity API to bind one graph with specific worker
  core.
6. Introduce graph clone API.
7. Introduce stream moving with scheduler work-queue in patch 8~12.
8. Add stats for new models.
9. Abstract default graph config process and integrate new model into
  example/l3fwd-graph. Add new parameters for model choosing.

We could run with new worker model by this:
./dpdk-l3fwd-graph -l 8,9,10,11 -n 4 -- -p 0x1 --config="(0,0,9)" -P
--model="dispatch"

References:
https://static.sched.com/hosted_files/dpdkuserspace22/a6/graph%20introduce%20remote%20dispatch%20for%20mult-core%20scaling.pdf


Zhirun Yan (17):
  graph: rename rte_graph_work as common
  graph: split graph worker into common and default model
  graph: move node process into inline function
  graph: add get/set graph worker model APIs
  graph: introduce graph node core affinity API
  graph: introduce graph bind unbind API
  graph: move node clone name func into private as common
  graph: introduce graph clone API for other worker core
  graph: add structure for stream moving between cores
  graph: introduce stream moving cross cores
  graph: enable create and destroy graph scheduling workqueue
  graph: introduce graph walk by cross-core dispatch
  graph: enable graph multicore dispatch scheduler model
  graph: add stats for cross-core dispatching
  examples/l3fwd-graph: introduce multicore dispatch worker model
  test/graph: add functional tests for mcore dispatch model
  doc: update multicore dispatch model in graph guides

 MAINTAINERS                                |   3 +-
 app/test/test_graph.c                      | 130 +++++
 doc/guides/prog_guide/graph_lib.rst        |  68 ++-
 examples/l3fwd-graph/main.c                | 231 ++++++--
 lib/graph/graph.c                          | 159 ++++++
 lib/graph/graph_debug.c                    |   6 +
 lib/graph/graph_populate.c                 |   1 +
 lib/graph/graph_private.h                  |  90 ++++
 lib/graph/graph_stats.c                    |  76 ++-
 lib/graph/meson.build                      |   4 +-
 lib/graph/node.c                           |  27 +-
 lib/graph/rte_graph.h                      |  65 +++
 lib/graph/rte_graph_model_mcore_dispatch.c | 191 +++++++
 lib/graph/rte_graph_model_mcore_dispatch.h | 134 +++++
 lib/graph/rte_graph_model_rtc.h            |  46 ++
 lib/graph/rte_graph_worker.c               |  21 +
 lib/graph/rte_graph_worker.h               | 504 +-----------------
 lib/graph/rte_graph_worker_common.h        | 589 +++++++++++++++++++++
 lib/graph/version.map                      |  10 +
 19 files changed, 1789 insertions(+), 566 deletions(-)
 create mode 100644 lib/graph/rte_graph_model_mcore_dispatch.c
 create mode 100644 lib/graph/rte_graph_model_mcore_dispatch.h
 create mode 100644 lib/graph/rte_graph_model_rtc.h
 create mode 100644 lib/graph/rte_graph_worker.c
 create mode 100644 lib/graph/rte_graph_worker_common.h

-- 
2.37.2