[PATCH v8 03/10] asm/rwonce: Introduce [READ|WRITE]_ONCE() support for __int128

Suravee Suthikulpanit
2024-10-31T18:43:16Z

From: Uros Bizjak <ubizjak@gmail.com>

Currently, [READ|WRITE]_ONCE() do not support variable of type __int128.
Re-define "__dword_type" from type "long long" to __int128 if supported.

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
---
include/asm-generic/rwonce.h | 2 +-
include/linux/compiler_types.h | 8 +++++++-
2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/include/asm-generic/rwonce.h b/include/asm-generic/rwonce.h
index 8d0a6280e982..8bf942ad5ef3 100644
--- a/include/asm-generic/rwonce.h
+++ b/include/asm-generic/rwonce.h
@@ -33,7 +33,7 @@
* (e.g. a virtual address) and a strong prevailing wind.
*/
#define compiletime_assert_rwonce_type(t) \
- compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \
+ compiletime_assert(__native_word(t) || sizeof(t) == sizeof(__dword_type), \
"Unsupported access size for {READ,WRITE}_ONCE().")

/*
diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h
index 1a957ea2f4fe..54b56ae25db7 100644
--- a/include/linux/compiler_types.h
+++ b/include/linux/compiler_types.h
@@ -469,6 +469,12 @@ struct ftrace_likely_data {
unsigned type: (unsigned type)0, \
signed type: (signed type)0

+#ifdef __SIZEOF_INT128__
+#define __dword_type __int128
+#else
+#define __dword_type long long
+#endif
+
#define __unqual_scalar_typeof(x) typeof( \
_Generic((x), \
char: (char)0, \
@@ -476,7 +482,7 @@ struct ftrace_likely_data {
__scalar_type_to_expr_cases(short), \
__scalar_type_to_expr_cases(int), \
__scalar_type_to_expr_cases(long), \
- __scalar_type_to_expr_cases(long long), \
+ __scalar_type_to_expr_cases(__dword_type), \
default: (x)))

/* Is this type a native word size -- useful for atomic operations */
--
2.34.1