[dpdk-dev] [PATCH v3 0/2] lib/ring: APIs to support custom element size

Honnappa Nagarahalli honnappa.nagarahalli at arm.com
Tue Oct 8 21:19:07 CEST 2019


The current rte_ring hard-codes the type of the ring element to 'void *',
hence the size of the element is hard-coded to 32b/64b. Since the ring
element type is not an input to rte_ring APIs, it results in couple
of issues:

1) If an application requires to store an element which is not 64b, it
   needs to write its own ring APIs similar to rte_event_ring APIs. This
   creates additional burden on the programmers, who end up making
   work-arounds and often waste memory.
2) If there are multiple libraries that store elements of the same
   type, currently they would have to write their own rte_ring APIs. This
   results in code duplication.

This patch adds new APIs to support configurable ring element size.
The APIs support custom element sizes by allowing to define the ring
element to be a multiple of 32b.

The aim is to achieve same performance as the existing ring
implementation. The patch adds same performance tests that are run
for existing APIs. This allows for performance comparison.

I also tested with memcpy. x86 shows significant improvements on bulk
and burst tests. On the Arm platform, I used, there is a drop of
4% to 6% in few tests. May be this is something that we can explore
later.

Note that this version skips changes to other libraries as I would
like to get an agreement on the implementation from the community.
They will be added once there is agreement on the rte_ring changes.

v3
 - Removed macro-fest and used inline functions
   (Stephen, Bruce)

v2
 - Change Event Ring implementation to use ring templates
   (Jerin, Pavan)

Honnappa Nagarahalli (2):
  lib/ring: apis to support configurable element size
  test/ring: add test cases for configurable element size ring

 app/test/Makefile                    |   1 +
 app/test/meson.build                 |   1 +
 app/test/test_ring_perf_elem.c       | 419 ++++++++++++
 lib/librte_ring/Makefile             |   3 +-
 lib/librte_ring/meson.build          |   3 +
 lib/librte_ring/rte_ring.c           |  45 +-
 lib/librte_ring/rte_ring.h           |   1 +
 lib/librte_ring/rte_ring_elem.h      | 946 +++++++++++++++++++++++++++
 lib/librte_ring/rte_ring_version.map |   2 +
 9 files changed, 1412 insertions(+), 9 deletions(-)
 create mode 100644 app/test/test_ring_perf_elem.c
 create mode 100644 lib/librte_ring/rte_ring_elem.h

-- 
2.17.1



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