lkml.org 
[lkml]   [2020]   [Sep]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
Subject[PATCH 0/5] Speed up mremap on large regions
From
mremap time can be optimized by moving entries at the PMD/PUD level if
the source and destination addresses are PMD/PUD-aligned and
PMD/PUD-sized. Enable moving at the PMD and PUD levels on arm64 and
x86. Other architectures where this type of move is supported and known to
be safe can also opt-in to these optimizations by enabling HAVE_MOVE_PMD
and HAVE_MOVE_PUD.

Observed Performance Improvements for remapping a PUD-aligned 1GB-sized
region on x86 and arm64:

- HAVE_MOVE_PMD is already enabled on x86 : N/A
- Enabling HAVE_MOVE_PUD on x86 : ~13x speed up

- Enabling HAVE_MOVE_PMD on arm64 : ~ 8x speed up
- Enabling HAVE_MOVE_PUD on arm64 : ~19x speed up

Altogether, HAVE_MOVE_PMD and HAVE_MOVE_PUD
give a total of ~150x speed up on arm64.


Kalesh Singh (5):
kselftests: vm: Add mremap tests
arm64: mremap speedup - Enable HAVE_MOVE_PMD
mm: Speedup mremap on 1GB or larger regions
arm64: mremap speedup - Enable HAVE_MOVE_PUD
x86: mremap speedup - Enable HAVE_MOVE_PUD

arch/Kconfig | 7 +
arch/arm64/Kconfig | 2 +
arch/arm64/include/asm/pgtable.h | 1 +
arch/x86/Kconfig | 1 +
mm/mremap.c | 211 +++++++++++++++++---
tools/testing/selftests/vm/.gitignore | 1 +
tools/testing/selftests/vm/Makefile | 1 +
tools/testing/selftests/vm/mremap_test.c | 243 +++++++++++++++++++++++
tools/testing/selftests/vm/run_vmtests | 11 +
9 files changed, 448 insertions(+), 30 deletions(-)
create mode 100644 tools/testing/selftests/vm/mremap_test.c

--
2.28.0.709.gb0816b6eb0-goog

\
 
 \ /
  Last update: 2020-10-01 00:23    [W:0.134 / U:8.620 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site