[dpdk-dev] [PATCH v6 00/10] update jhash function

[Pablo de Lara <pablo.de.lara.guarch@intel.com>]

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 35% 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, and add new unit tests.

changes in v6:
- Use RTE_DIM macro, so it saves lines of code
- Correct mistaken performance improvement
- Add deprecated attribute, instead of printing a message calling it
- Add note stating the changes in release notes

changes in v5:
- Add functional tests (mainly to test that all functions 
  return the expected hash values)
- Modify range of key sizes to test
- Change order of output for perf tests, so it is clearer
  to compare different hash functions for same key size/initial value
- Add new initial value to test in the hash functions
- Fix some errors caught by checkpatch
 
changes in v4:
- Simplify key alignment checks
- Include missing x86 arch check

changes in v3:

- Update rte_jhash_1word, rte_jhash_2words and rte_jhash_3words
  functions

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

De Lara Guarch, Pablo (6):
  test/hash: move hash function perf tests to separate file
  test/hash: improve accuracy on cycle measurements
  test/hash: update key size range and initial values for testing
  test/hash: add new functional tests for hash functions
  hash: add two new functions to jhash library
  test/hash: verify rte_jhash_1word/2words/3words
  test/hash: change order of loops in hash function tests
  hash: update jhash function with the latest available
  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_functions.c        | 321 ++++++++++++++++++++++++++++++++
 app/test/test_hash_perf.c             |  71 +------
 doc/guides/rel_notes/new_features.rst |   5 +
 lib/librte_hash/rte_jhash.h           | 339 +++++++++++++++++++++++++---------
 7 files changed, 584 insertions(+), 159 deletions(-)
 create mode 100644 app/test/test_hash_functions.c

-- 
2.4.2