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Gmane
From: Jiang Liu <liuj97 <at> gmail.com>
Subject: [PATCH v5 0/7] Optimize jump label implementation for ARM64
Newsgroups: gmane.linux.ports.arm.kernel
Date: Friday 18th October 2013 15:19:54 UTC (over 4 years ago)
From: Jiang Liu 

This patchset tries to optimize arch specfic jump label implementation
for ARM64 by dynamic kernel text patching.

To enable this feature, your toolchain must support "asm goto" extension
and "%c" constraint extesion. Current GCC for AARCH64 doesn't support
"%c", and there's a patch for it now:
http://gcc.gnu.org/ml/gcc-patches/2013-10/msg01314.html

It has been tested on ARM Fast mode and a real hardware platform.

Any comments are welcomed!

V4->V5:
1) rework the stop_machine() related code
2) rework aarch64_insn_gen_nop()

V3->V4:
1) resolve a race condition in kernel text patching
2) address other review comments

V2->V3:
1) fix a bug in comparing signed and unsigned values
2) detect big endian by checking __AARCH64EB__

V1->V2: address review comments of V1
1) refine comments
2) add a new interface to always synchronize with stop_machine()
   when patching code
3) handle endian issue when patching code

Jiang Liu (7):
  arm64: introduce basic aarch64 instruction decoding helpers
  arm64: introduce interfaces to hotpatch kernel and module code
  arm64: move encode_insn_immediate() from module.c to insn.c
  arm64: introduce aarch64_insn_gen_{nop|branch_imm}() helper functions
  arm64, jump label: detect %c support for ARM64
  arm64, jump label: optimize jump label implementation
  jump_label: use defined macros instead of hard-coding for better
    readability

 arch/arm64/Kconfig                  |   1 +
 arch/arm64/include/asm/insn.h       | 121 +++++++++++++++++
 arch/arm64/include/asm/jump_label.h |  52 +++++++
 arch/arm64/kernel/Makefile          |   3 +-
 arch/arm64/kernel/insn.c            | 263
++++++++++++++++++++++++++++++++++++
 arch/arm64/kernel/jump_label.c      |  58 ++++++++
 arch/arm64/kernel/module.c          | 153 +++++++--------------
 include/linux/jump_label.h          |  15 +-
 scripts/gcc-goto.sh                 |   2 +-
 9 files changed, 554 insertions(+), 114 deletions(-)
 create mode 100644 arch/arm64/include/asm/insn.h
 create mode 100644 arch/arm64/include/asm/jump_label.h
 create mode 100644 arch/arm64/kernel/insn.c
 create mode 100644 arch/arm64/kernel/jump_label.c

-- 
1.8.1.2
 
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