From 62479586532715b6da4777374a6f53b32453385e Mon Sep 17 00:00:00 2001
From: Catalin Marinas <catalin.marinas@arm.com>
Date: Thu, 21 Mar 2013 16:28:47 +0000
Subject: arm64: klib: Optimised atomic bitops

This patch implements the AArch64-specific atomic bitops functions using
exclusive memory accesses to avoid locking.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
---
 arch/arm64/include/asm/bitops.h | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

(limited to 'arch/arm64/include/asm/bitops.h')

diff --git a/arch/arm64/include/asm/bitops.h b/arch/arm64/include/asm/bitops.h
index 5e693073b030..aa5b59d6ba43 100644
--- a/arch/arm64/include/asm/bitops.h
+++ b/arch/arm64/include/asm/bitops.h
@@ -32,6 +32,16 @@
 #error only <linux/bitops.h> can be included directly
 #endif
 
+/*
+ * Little endian assembly atomic bitops.
+ */
+extern void set_bit(int nr, volatile unsigned long *p);
+extern void clear_bit(int nr, volatile unsigned long *p);
+extern void change_bit(int nr, volatile unsigned long *p);
+extern int test_and_set_bit(int nr, volatile unsigned long *p);
+extern int test_and_clear_bit(int nr, volatile unsigned long *p);
+extern int test_and_change_bit(int nr, volatile unsigned long *p);
+
 #include <asm-generic/bitops/builtin-__ffs.h>
 #include <asm-generic/bitops/builtin-ffs.h>
 #include <asm-generic/bitops/builtin-__fls.h>
@@ -45,9 +55,13 @@
 #include <asm-generic/bitops/hweight.h>
 #include <asm-generic/bitops/lock.h>
 
-#include <asm-generic/bitops/atomic.h>
 #include <asm-generic/bitops/non-atomic.h>
 #include <asm-generic/bitops/le.h>
-#include <asm-generic/bitops/ext2-atomic.h>
+
+/*
+ * Ext2 is defined to use little-endian byte ordering.
+ */
+#define ext2_set_bit_atomic(lock, nr, p)	test_and_set_bit_le(nr, p)
+#define ext2_clear_bit_atomic(lock, nr, p)	test_and_clear_bit_le(nr, p)
 
 #endif /* __ASM_BITOPS_H */
-- 
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