[PATCH 0/2] arm64: Use static keys for CPU features

From: Catalin Marinas
Date: Thu Aug 25 2016 - 13:26:45 EST


This series is aimed to optimise the arm64 cpus_have_cap() functionality
(checking for the presence of certain CPU capabilities/features) to
avoid a bitmap test and use a jump label instead, patched at boot time.

While this series may not provide a clear performance improvement with
the current kernel, it will be more beneficial with new features like
TTBR0 PAN are which are used on hot paths (get_user/put_user, thread
switching).

Catalin Marinas (2):
jump_labels: Allow array initialisers
arm64: Use static keys for CPU features

Documentation/static-keys.txt | 8 ++++++++
arch/arm64/include/asm/cpufeature.h | 14 +++++++++++---
arch/arm64/kernel/cpufeature.c | 3 +++
arch/arm64/kernel/cpuinfo.c | 6 ++++++
include/linux/jump_label.h | 12 ++++++++++++
5 files changed, 40 insertions(+), 3 deletions(-)