ARM: 8047/1: rwsem: use asm-generic rwsem implementation

asm-generic offers an atomic-add based rwsem implementation, which
can avoid the need for heavier, spinlock-based synchronisation on the
fast path.

This patch makes use of the optimised implementation for ARM CPUs.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 5850617..ce64b7f 100644 (file)
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -165,12 +165,9 @@ config TRACE_IRQFLAGS_SUPPORT
        bool
        default y
 
-config RWSEM_GENERIC_SPINLOCK
-       bool
-       default y
-
 config RWSEM_XCHGADD_ALGORITHM
        bool
+       default y
 
 config ARCH_HAS_ILOG2_U32
        bool

diff --git a/arch/arm/include/asm/Kbuild b/arch/arm/include/asm/Kbuild
index 23e728e..f5a3576 100644 (file)
--- a/arch/arm/include/asm/Kbuild
+++ b/arch/arm/include/asm/Kbuild
@@ -21,6 +21,7 @@ generic-y += parport.h
 generic-y += poll.h
 generic-y += preempt.h
 generic-y += resource.h
+generic-y += rwsem.h
 generic-y += sections.h
 generic-y += segment.h
 generic-y += sembuf.h