[PATCH v2 0/3] mm/slub: Fix count_partial() problem

From: Xunlei Pang
Date: Mon Aug 10 2020 - 08:18:01 EST


v1->v2:
- Improved changelog and variable naming for PATCH 1~2.
- PATCH3 adds per-cpu counter to avoid performance regression
in concurrent __slab_free().

[Testing]
On my 32-cpu 2-socket physical machine:
Intel(R) Xeon(R) CPU E5-2650 v2 @ 2.60GHz
perf stat --null --repeat 10 -- hackbench 20 thread 20000

== original, no patched
19.211637055 seconds time elapsed ( +- 0.57% )

== patched with patch1~2
Performance counter stats for 'hackbench 20 thread 20000' (10 runs):

21.731833146 seconds time elapsed ( +- 0.17% )

== patched with patch1~3
Performance counter stats for 'hackbench 20 thread 20000' (10 runs):

19.112106847 seconds time elapsed ( +- 0.64% )


Xunlei Pang (3):
mm/slub: Introduce two counters for partial objects
mm/slub: Get rid of count_partial()
mm/slub: Use percpu partial free counter

mm/slab.h | 2 +
mm/slub.c | 124 +++++++++++++++++++++++++++++++++++++++++++-------------------
2 files changed, 89 insertions(+), 37 deletions(-)

--
1.8.3.1