* [PATCH] ARM: enable CONFIG_KTIME_SCALAR
@ 2011-03-01 18:38 Rob Herring
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From: Rob Herring @ 2011-03-01 18:38 UTC (permalink / raw)
To: linux-arm-kernel
From: Rob Herring <rob.herring@calxeda.com>
Use straight 64-bit values as 64-bit operations are fairly efficient on ARM.
Comparing the asm output with and without KTIME_SCALAR, using 64-bit math
generates clearly better code.
Comparing kernel/hrtimer.c .text size, it goes from 0x1414 to 0x119c with
this change.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
---
arch/arm/Kconfig | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 166efa2..0efbea4 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -63,6 +63,10 @@ config GENERIC_CLOCKEVENTS_BROADCAST
depends on GENERIC_CLOCKEVENTS
default y if SMP
+config KTIME_SCALAR
+ bool
+ default y
+
config HAVE_TCM
bool
select GENERIC_ALLOCATOR
--
1.7.1
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