diff options
| author | Will Deacon <will.deacon@arm.com> | 2012-07-06 15:45:39 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2012-07-09 17:41:11 +0100 |
| commit | 8c56cc8be5b38e3684eba96dc9b3f7ca7e495755 (patch) | |
| tree | eccb882c8c5f1cc81fc226c769fc9ec99a45145b /arch/arm/Kconfig | |
| parent | 4295b898f5a5c7e62ae68e7a4ecc4b414622ffe6 (diff) | |
ARM: 7449/1: use generic strnlen_user and strncpy_from_user functions
This patch implements the word-at-a-time interface for ARM using the
same algorithm as x86. We use the fls macro from ARMv5 onwards, where
we have a clz instruction available which saves us a mov instruction
when targetting Thumb-2. For older CPUs, we use the magic 0x0ff0001
constant. Big-endian configurations make use of the implementation from
asm-generic.
With this implemented, we can replace our byte-at-a-time strnlen_user
and strncpy_from_user functions with the optimised generic versions.
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/Kconfig')
| -rw-r--r-- | arch/arm/Kconfig | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 8c9d264f2108..574561a66d75 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -46,6 +46,8 @@ config ARM select GENERIC_SMP_IDLE_THREAD select KTIME_SCALAR select GENERIC_CLOCKEVENTS_BROADCAST if SMP + select GENERIC_STRNCPY_FROM_USER + select GENERIC_STRNLEN_USER help The ARM series is a line of low-power-consumption RISC chip designs licensed by ARM Ltd and targeted at embedded applications and |