Re: [dpdk-dev] [RFC] eventdev: introduce event dispatcher

[Luca Boccassi <bluca@debian.org>]

On Thu, 2021-02-18 at 19:30 +0100, Mattias Rönnblom wrote:
> The purpose of the event dispatcher is primarily to decouple different
> parts of an application (e.g., processing pipeline stages), which
> share the same underlying event device.
> 
> The event 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 the destination queue id.
> 
> 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 event dispatcher binds callbacks to queue ids.
> 
> An event 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 event 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.
> 
> Signed-off-by: Mattias Rönnblom <mattias.ronnblom@ericsson.com>
> ---
>  lib/librte_eventdev/Makefile                 |   2 +
>  lib/librte_eventdev/meson.build              |   6 +-
>  lib/librte_eventdev/rte_event_dispatcher.c   | 420 +++++++++++++++++++
>  lib/librte_eventdev/rte_event_dispatcher.h   | 251 +++++++++++
>  lib/librte_eventdev/rte_eventdev_version.map |  10 +
>  5 files changed, 687 insertions(+), 2 deletions(-)
>  create mode 100644 lib/librte_eventdev/rte_event_dispatcher.c
>  create mode 100644 lib/librte_eventdev/rte_event_dispatcher.h

Hi,

Is this intended to be used by applications or by PMDs? If the former,
then IMHO the interface should really be based around (or allow using)
FDs, so that it can be polled. Applications normally have more event
sources that just DPDK.

-- 
Kind regards,
Luca Boccassi