On Wed, Jun 7, 2023 at 9:30 AM Zhirun Yan <zhirun....@intel.com> wrote: > > Update graph documentation to introduce new multicore dispatch model.
Please squash this to relevant implementation patches, No need for separate patch. This is the contribution guideline followed. > > Signed-off-by: Haiyue Wang <haiyue.w...@intel.com> > Signed-off-by: Cunming Liang <cunming.li...@intel.com> > Signed-off-by: Zhirun Yan <zhirun....@intel.com> > --- > doc/guides/prog_guide/graph_lib.rst | 68 +++++++++++++++++++++++++++-- > 1 file changed, 64 insertions(+), 4 deletions(-) > > diff --git a/doc/guides/prog_guide/graph_lib.rst > b/doc/guides/prog_guide/graph_lib.rst > index 1cfdc86433..8c2c2816ed 100644 > --- a/doc/guides/prog_guide/graph_lib.rst > +++ b/doc/guides/prog_guide/graph_lib.rst > @@ -189,14 +189,74 @@ In the above example, A graph object will be created > with ethdev Rx > node of port 0 and queue 0, all ipv4* nodes in the system, > and ethdev tx node of all ports. > > -Multicore graph processing > -~~~~~~~~~~~~~~~~~~~~~~~~~~ > -In the current graph library implementation, specifically, > -``rte_graph_walk()`` and ``rte_node_enqueue*`` fast path API functions > +Graph models chossing Graph models > +~~~~~~~~~~~~~~~~~~~~~ > +Currently, there are 2 different walking models. Use macro > +RTE_GRAPH_MODEL_SELECT to set the model in compile time. Also offers the > +ability to choose models in runtime by not defining RTE_GRAPH_MODEL_SELECT. > +For application, must #define RTE_GRAPH_MODEL_SELECT before including > +rte_graph_worker.h Some rewording as suggestion. Graph models ~~~~~~~~~~~~ There are two different kinds of graph walking models. User can select the model using ``rte_graph_worker_model_set()`` API. If the application decides to use only one model, the fast path check can be avoided by defining the model with RTE_GRAPH_MODEL_SELECT. For example: .. code-block:: console #define RTE_GRAPH_MODEL_SELECT RTE_GRAPH_MODEL_RTC #include "rte_graph_worker.h" > + > +In l3fwd-graph, set RTE_GRAPH_MODEL_SELECT as the model explicitly for > +performance-sensitive use case. > +Or set the macro as GRAPH_MODEL_MCORE_RUNTIME_SELECT. And parse > +``"--model=NAME"`` in cmdline and use ``rte_graph_worker_model_set()`` > +to set the walking model in runtime. Please move to doc/guides/sample_app_ug/l3_forward_graph.rst > + > +RTC (Run-To-Completion) > +^^^^^^^^^^^^^^^^^^^^^^^ > +This is the default graph walking model. Specifically, > +``rte_graph_walk_rtc()`` and ``rte_node_enqueue*`` fast path API functions > are designed to work on single-core to have better performance. > The fast path API works on graph object, So the multi-core graph > processing strategy would be to create graph object PER WORKER. > > +Example: > + > +Graph: node-0 -> node-1 -> node-2 @Core0. > + > +.. code-block:: diff > + > + + - - - - - - - - - - - - - - - - - - - - - + > + ' Core #0 ' > + ' ' > + ' +--------+ +---------+ +--------+ ' > + ' | Node-0 | --> | Node-1 | --> | Node-2 | ' > + ' +--------+ +---------+ +--------+ ' > + ' ' > + + - - - - - - - - - - - - - - - - - - - - - + > + > +Dispatch model > +^^^^^^^^^^^^^^ > +The dispatch 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. > + > +Use ``rte_graph_model_mcore_dispatch_lcore_affinity_set()`` to set lcore > affinity > +with the node. > +Each worker core will have a graph repetition. Use ``rte_graph_clone()`` to > clone > +graph for each worker and use``rte_graph_model_mcore_dispatch_core_bind()`` > to > +bind graph with the worker core. > + > +Example: > + > +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 | ' > + ' +--------+ ' ' +--------+ +--------+ ' ' +--------+ ' > + ' ' ' | ' ' ^ ' > + + - - - - - -+ +- - -|- - - - - - - - - - + + - - -|- - -+ > + | | > + + - - - - - - - - - - - - - - - - + > + > + > In fast path > ~~~~~~~~~~~~ > Typical fast-path code looks like below, where the application > -- > 2.37.2 >
