Re: [PATCH v5 0/7] service cores: cover letter

[Jerin Jacob <jerin.jacob@caviumnetworks.com>]

-----Original Message-----
> Date: Tue, 11 Jul 2017 15:19:26 +0100
> From: Harry van Haaren <harry.van.haaren@intel.com>
> To: dev@dpdk.org
> CC: thomas@monjalon.net, jerin.jacob@caviumnetworks.com,
>  keith.wiles@intel.com, bruce.richardson@intel.com, Harry van Haaren
>  <harry.van.haaren@intel.com>
> Subject: [PATCH v5 0/7] service cores: cover letter
> X-Mailer: git-send-email 2.7.4
> 
> This patchset introduces service cores to DPDK. A service core
> is an lcore that performs functions to abstract away details of
> differences in environment of the application.
> 
> An example is using the eventdev API, where either a software or hardware
> PMD performs scheduling. In the case of the software PMD an lcore is
> required to perform scheduling, which means application logic would have
> to be aware of the PMD running under the API. To abstract away the
> differences in HW / SW PMDs, service cores can run the SW PMD service
> without application logic specifying the exact cores to use. Note that
> eventdev is only one API that benefits; timers, interrupts handling,
> statistics and monitoring, and a range of other infrastructure that
> requires a slice of CPU time may all benefit from service cores.
> 
> The application is not obliged to manually use the service cores API,
> however if an application wishes to use the service cores API for fine
> grained control over how the services are run, this is possible. Deciding
> between a performance threading-profile and scaled-down profile can be
> achieved by advanced usage of service cores and setting the lcore mappings.
> 
> Patch 5/7 shows how a PMD can register a service to run a function. This
> is then available (along with any other registered services) to be run by
> the service cores. Patches 6/7 and 7/7 add documentation, and claim
> maintainership.
> 
> Regards, -Harry

Nice feature. This series Looks good to me.
Series Acked-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>

IMO, We can add this series in RC2 if there are no objections.

Two points:

1) There is a check-git log warning. It could be fixed it on apply.

Wrong headline uppercase:
	service cores: EAL init changes


2) Based on the mail[1], It is agreed that we need to refactor eal_parse_service_coremask() and
eal_parse__coremask() code in future to avoid code duplication in coremask parsing
logic.

[1]
http://dpdk.org/ml/archives/dev/2017-July/070610.html

> 
> v5:
> Jerin:
> - Fix documentation warnings
> - Rename variables to better names
> - Enable statistics per-service
> - Improve atomic operation flag checks
> - Reworked function to rte_service_start_with_defaults()
> - Added memory barriers to lcore_add() and lcore_del()
> - Simplified EAL code, reduced duplication and makes it more maintainable
> 
> Jerin/Thomas:
> - Rename component header to rte_service_component.h
> 
> v4:
> - Range of fixes as suggested by Jerin
> - Improved unit tests, ensuring ex-service cores become available to app
> - Added functions to EXPERIMENTAL tag in .map files (Thomas)
> - Added @warning experimental notes to Doxygen API documentation (Thomas)
> - Various smaller fixes / cleanups
> - See commit notes for details
> 
> v3:
> - Added docs
> - Added release notes
> - Updated maintainers file
> - Compile checks with devtools/test-build.sh
> - Validated patches apply to latest dpdk/master
> - Based on discussion, rte_service_iterate() is *not* included,
>   but could be adding at a later date if use-cases require it.
> - Future work includes enabling the eventdev_pipeline sample app, but there
>   is still some churn there to enable both HW/SW PMDs seamlessly. Once sample
>   app is enabled a service core walk-through with that sample app can be added
>   to the docs, to provide a tutorial on service-core usage.
> 
> 
> Harry van Haaren (7):
>   service cores: header and implementation
>   service cores: EAL init changes
>   service cores: coremask parsing
>   service cores: add unit tests
>   event/sw: enable SW PMD with service capability
>   doc: add service cores to doc and release notes
>   maintainers: claim service cores
> 
>  MAINTAINERS                                        |   7 +
>  doc/api/doxy-api-index.md                          |   1 +
>  doc/guides/eventdevs/sw.rst                        |   4 +-
>  doc/guides/prog_guide/index.rst                    |   1 +
>  doc/guides/prog_guide/service_cores.rst            |  81 +++
>  doc/guides/rel_notes/release_17_08.rst             |   8 +
>  drivers/event/sw/sw_evdev.c                        |  32 +
>  drivers/event/sw/sw_evdev.h                        |   3 +
>  lib/librte_eal/bsdapp/eal/Makefile                 |   1 +
>  lib/librte_eal/bsdapp/eal/eal.c                    |  18 +
>  lib/librte_eal/bsdapp/eal/rte_eal_version.map      |  23 +
>  lib/librte_eal/common/Makefile                     |   1 +
>  lib/librte_eal/common/eal_common_lcore.c           |   1 +
>  lib/librte_eal/common/eal_common_options.c         |  91 ++-
>  lib/librte_eal/common/include/rte_eal.h            |   4 +
>  lib/librte_eal/common/include/rte_lcore.h          |   3 +-
>  lib/librte_eal/common/include/rte_service.h        | 387 +++++++++++
>  .../common/include/rte_service_component.h         | 144 +++++
>  lib/librte_eal/common/rte_service.c                | 704 +++++++++++++++++++++
>  lib/librte_eal/linuxapp/eal/Makefile               |   1 +
>  lib/librte_eal/linuxapp/eal/eal.c                  |  18 +
>  lib/librte_eal/linuxapp/eal/eal_thread.c           |   9 +-
>  lib/librte_eal/linuxapp/eal/rte_eal_version.map    |  23 +
>  test/test/Makefile                                 |   2 +
>  test/test/test_service_cores.c                     | 599 ++++++++++++++++++
>  25 files changed, 2162 insertions(+), 4 deletions(-)
>  create mode 100644 doc/guides/prog_guide/service_cores.rst
>  create mode 100644 lib/librte_eal/common/include/rte_service.h
>  create mode 100644 lib/librte_eal/common/include/rte_service_component.h
>  create mode 100644 lib/librte_eal/common/rte_service.c
>  create mode 100644 test/test/test_service_cores.c
> 
> -- 
> 2.7.4
>