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authorJiri Kosina <jkosina@suse.cz>2012-10-28 19:28:52 +0100
committerJiri Kosina <jkosina@suse.cz>2012-10-28 19:29:19 +0100
commit3bd7bf1f0fe14f591c089ae61bbfa9bd356f178a (patch)
tree0058693cc9e70b7461dae551f8a19aff2efd13ca /arch/arm/include/asm/mutex.h
parentf16f84937d769c893492160b1a8c3672e3992beb (diff)
parente657e078d3dfa9f96976db7a2b5fd7d7c9f1f1a6 (diff)
Merge branch 'master' into for-next
Sync up with Linus' tree to be able to apply Cesar's patch against newer version of the code. Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'arch/arm/include/asm/mutex.h')
-rw-r--r--arch/arm/include/asm/mutex.h9
1 files changed, 7 insertions, 2 deletions
diff --git a/arch/arm/include/asm/mutex.h b/arch/arm/include/asm/mutex.h
index b1479fd04a9..87c044910fe 100644
--- a/arch/arm/include/asm/mutex.h
+++ b/arch/arm/include/asm/mutex.h
@@ -9,8 +9,13 @@
#define _ASM_MUTEX_H
/*
* On pre-ARMv6 hardware this results in a swp-based implementation,
- * which is the most efficient. For ARMv6+, we emit a pair of exclusive
- * accesses instead.
+ * which is the most efficient. For ARMv6+, we have exclusive memory
+ * accessors and use atomic_dec to avoid the extra xchg operations
+ * on the locking slowpaths.
*/
+#if __LINUX_ARM_ARCH__ < 6
#include <asm-generic/mutex-xchg.h>
+#else
+#include <asm-generic/mutex-dec.h>
#endif
+#endif /* _ASM_MUTEX_H */