[RFC][PATCH 04/12] types: Introduce [us]128

[Peter Zijlstra]

Introduce [us]128 (when available). Unlike [us]64, ensure they are
always naturally aligned.

This also enables 128bit wide atomics (which require natural
alignment) such as cmpxchg128().

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
 include/linux/types.h      |    5 +++++
 include/uapi/linux/types.h |    4 ++++
 2 files changed, 9 insertions(+)

--- a/include/linux/types.h
+++ b/include/linux/types.h
@@ -10,6 +10,11 @@
 #define DECLARE_BITMAP(name,bits) \
 	unsigned long name[BITS_TO_LONGS(bits)]
 
+#ifdef __SIZEOF_INT128__
+typedef __s128 s128;
+typedef __u128 u128;
+#endif
+
 typedef u32 __kernel_dev_t;
 
 typedef __kernel_fd_set		fd_set;
--- a/include/uapi/linux/types.h
+++ b/include/uapi/linux/types.h
@@ -13,6 +13,10 @@
 
 #include <linux/posix_types.h>
 
+#ifdef __SIZEOF_INT128__
+typedef __signed__ __int128 __s128 __attribute__((aligned(16)));
+typedef unsigned __int128 __u128 __attribute__((aligned(16)));
+#endif
 
 /*
  * Below are truly Linux-specific types that should never collide with