[v6,0/4] hash: add SVE support for bulk key lookup

Message ID 20240311232112.736613-1-yoan.picchi@arm.com (mailing list archive)
Headers
Series hash: add SVE support for bulk key lookup |

Message

Yoan Picchi March 11, 2024, 11:21 p.m. UTC
This patchset adds SVE support for the signature comparison in the cuckoo
hash lookup and improves the existing NEON implementation. These
optimizations required changes to the data format and signature of the
relevant functions to support dense hitmasks (no padding) and having the
primary and secondary hitmasks interleaved instead of being in their own
array each.

Benchmarking the cuckoo hash perf test, I observed this effect on speed:
  There are no significant changes on Intel (ran on Sapphire Rapids)
  Neon is up to 7-10% faster (ran on ampere altra)
  128b SVE is about 3-5% slower than the optimized neon (ran on a graviton
    3 cloud instance)
  256b SVE is about 0-3% slower than the optimized neon (ran on a graviton
    3 cloud instance)

V2->V3:
  Remove a redundant if in the test
  Change a couple int to uint16_t in compare_signatures_dense
  Several codding-style fix

V3->V4:
  Rebase

V4->V5:
  Commit message

V5->V6:
  Move the arch-specific code into new arch-specific files
  Isolate the data struture refactor from adding SVE

Yoan Picchi (4):
  hash: pack the hitmask for hash in bulk lookup
  hash: optimize compare signature for NEON
  test/hash: check bulk lookup of keys after collision
  hash: add SVE support for bulk key lookup

 .mailmap                                  |   2 +
 app/test/test_hash.c                      |  99 ++++++++---
 lib/hash/arch/arm/compare_signatures.h    | 117 +++++++++++++
 lib/hash/arch/common/compare_signatures.h |  38 +++++
 lib/hash/arch/x86/compare_signatures.h    |  53 ++++++
 lib/hash/rte_cuckoo_hash.c                | 197 ++++++++++++----------
 lib/hash/rte_cuckoo_hash.h                |   1 +
 7 files changed, 392 insertions(+), 115 deletions(-)
 create mode 100644 lib/hash/arch/arm/compare_signatures.h
 create mode 100644 lib/hash/arch/common/compare_signatures.h
 create mode 100644 lib/hash/arch/x86/compare_signatures.h