[dpdk-dev] [PATCH v2 0/6] update jhash function

Pablo de Lara pablo.de.lara.guarch at intel.com
Fri Apr 24 13:23:01 CEST 2015


Jenkins hash function was developed originally in 1996,
and was integrated in first versions of DPDK.
The function has been improved in 2006,
achieving up to 60% better performance, compared to the original one.

This patchset updates the current jhash in DPDK,
including two new functions that generate two hashes from a single key.

It also separates the existing hash function performance tests to
another file, to make it quicker to run.

changes in v2:

- Split single commit in three commits, one that updates the existing functions
  and another that adds two new functions and use one of those functions 
  as a base to be called by the other ones.
- Remove some unnecessary ifdefs in the code.
- Add new macros to help on the reutilization of constants
- Separate hash function performance tests to another file
  and improve cycle measurements.
- Rename existing function rte_jhash2 to rte_jhash_32b
  (something more meaninful) and mark rte_jhash2 as
  deprecated

Pablo de Lara (6):
  test/hash: move hash function perf tests to separate file
  test/hash: improve accuracy on cycle measurements
  hash: update jhash function with the latest available
  hash: add two new functions to jhash library
  hash: remove duplicated code
  hash: rename rte_jhash2 to rte_jhash_32b

 app/test/Makefile               |    1 +
 app/test/test_func_reentrancy.c |    2 +-
 app/test/test_hash.c            |    4 +-
 app/test/test_hash_func_perf.c  |  145 ++++++++++++++++++
 app/test/test_hash_perf.c       |   71 +---------
 lib/librte_hash/rte_jhash.h     |  313 +++++++++++++++++++++++++++++----------
 6 files changed, 387 insertions(+), 149 deletions(-)
 create mode 100644 app/test/test_hash_func_perf.c

-- 
1.7.4.1



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