[PATCH v3 0/2] KSM: Replace jhash2 with xxhash

From: Timofey Titovets
Date: Mon Sep 25 2017 - 15:33:35 EST


ksm use jhash2 for hashing pages,
in 4.14 xxhash has been merged to mainline kernel.

xxhash much faster then jhash2 on big inputs (32 byte+)

xxhash has 2 versions, one with 32-bit hash and
one with 64-bit hash.

64-bit version works faster then 32-bit on 64-bit arch.

So lets get better from two worlds,
create arch dependent xxhash() function that will use
fastest algo for current arch.
This a first patch.

Performance info and ksm update can be found in second patch.

Changelog:
v1 -> v2:
- Move xxhash() to xxhash.h/c and separate patches

v2 -> v3:
- Move xxhash() xxhash.c -> xxhash.h
- replace xxhash_t with 'unsigned long'
- update kerneldoc above xxhash()

Timofey Titovets (2):
xxHash: create arch dependent 32/64-bit xxhash()
KSM: Replace jhash2 with xxhash

include/linux/xxhash.h | 23 +++++++++++++++++++++++
mm/Kconfig | 1 +
mm/ksm.c | 14 +++++++-------
3 files changed, 31 insertions(+), 7 deletions(-)

--
2.14.1