On Thu, Oct 12, 2023 at 10:55 AM Mattias Rönnblom <mattias.ronnb...@ericsson.com> wrote: > > The purpose of the dispatcher library is to decouple different parts > of an eventdev-based application (e.g., processing pipeline stages), > sharing the same underlying event device. > > The dispatcher replaces the conditional logic (often, a switch > statement) that typically follows an event device dequeue operation, > where events are dispatched to different parts of the application > based on event meta data, such as the queue id or scheduling type. > > The concept is similar to a UNIX file descriptor event loop library. > Instead of tying callback functions to fds as for example libevent > does, the dispatcher relies on application-supplied matching callback > functions to decide where to deliver events. > > A dispatcher is configured to dequeue events from a specific event > device, and ties into the service core framework, to do its (and the > application's) work. > > The dispatcher provides a convenient way for an eventdev-based > application to use service cores for application-level processing, and > thus for sharing those cores with other DPDK services. > > Although the dispatcher adds some overhead, experience suggests that > the net effect on the application (both synthetic benchmarks and more > real-world applications) may well be positive. This is primarily due > to clustering (see programming guide) reducing cache misses. > > Benchmarking indicates that the overhead is ~10 cc/event (on a > large core), with a handful of often-used handlers. > > The dispatcher does not support run-time reconfiguration. > > The use of the dispatcher library is optional, and an eventdev-based > application may still opt to access the event device using direct > eventdev API calls, or by some other means. > > Mattias Rönnblom (3): > lib: introduce dispatcher library > test: add dispatcher test suite > doc: add dispatcher programming guide > > MAINTAINERS | 6 + > app/test/meson.build | 1 + > app/test/test_dispatcher.c | 1056 ++++++++++++++++++++++ > doc/api/doxy-api-index.md | 1 + > doc/api/doxy-api.conf.in | 1 + > doc/guides/prog_guide/dispatcher_lib.rst | 433 +++++++++ > doc/guides/prog_guide/index.rst | 1 + > doc/guides/rel_notes/release_23_11.rst | 5 + > lib/dispatcher/meson.build | 13 + > lib/dispatcher/rte_dispatcher.c | 694 ++++++++++++++ > lib/dispatcher/rte_dispatcher.h | 458 ++++++++++ > lib/dispatcher/version.map | 20 + > lib/meson.build | 2 + > 13 files changed, 2691 insertions(+) > create mode 100644 app/test/test_dispatcher.c > create mode 100644 doc/guides/prog_guide/dispatcher_lib.rst > create mode 100644 lib/dispatcher/meson.build > create mode 100644 lib/dispatcher/rte_dispatcher.c > create mode 100644 lib/dispatcher/rte_dispatcher.h > create mode 100644 lib/dispatcher/version.map >
Thanks for this latest revision, it lgtm. I fixed a few grammar issues in the documentation and used simple .. note:: blocks to be consistent with the rest of our docs. Applied, thanks Mattias. -- David Marchand
