From: Arnd Bergmann <arnd@xxxxxxxx> [ Upstream commit 920fdab7b3ce98c14c840261e364f490f3679a62 ] On arm64 build with clang, sometimes the __cmpxchg_mb is not inlined when CONFIG_OPTIMIZE_INLINING is set. Clang then fails a compile-time assertion, because it cannot tell at compile time what the size of the argument is: mm/memcontrol.o: In function `__cmpxchg_mb': memcontrol.c:(.text+0x1a4c): undefined reference to `__compiletime_assert_175' memcontrol.c:(.text+0x1a4c): relocation truncated to fit: R_AARCH64_CALL26 against undefined symbol `__compiletime_assert_175' Mark all of the cmpxchg() style functions as __always_inline to ensure that the compiler can see the result. Acked-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> Reported-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Link: https://github.com/ClangBuiltLinux/linux/issues/648 Reviewed-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Tested-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Reviewed-by: Andrew Murray <andrew.murray@xxxxxxx> Tested-by: Andrew Murray <andrew.murray@xxxxxxx> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Signed-off-by: Will Deacon <will@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/arm64/include/asm/cmpxchg.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/arm64/include/asm/cmpxchg.h b/arch/arm64/include/asm/cmpxchg.h index 3b09382815419..d8b01c7c9cd3f 100644 --- a/arch/arm64/include/asm/cmpxchg.h +++ b/arch/arm64/include/asm/cmpxchg.h @@ -74,7 +74,7 @@ __XCHG_CASE( , , mb_8, dmb ish, nop, , a, l, "memory") #undef __XCHG_CASE #define __XCHG_GEN(sfx) \ -static inline unsigned long __xchg##sfx(unsigned long x, \ +static __always_inline unsigned long __xchg##sfx(unsigned long x, \ volatile void *ptr, \ int size) \ { \ @@ -116,7 +116,7 @@ __XCHG_GEN(_mb) #define xchg(...) __xchg_wrapper( _mb, __VA_ARGS__) #define __CMPXCHG_GEN(sfx) \ -static inline unsigned long __cmpxchg##sfx(volatile void *ptr, \ +static __always_inline unsigned long __cmpxchg##sfx(volatile void *ptr, \ unsigned long old, \ unsigned long new, \ int size) \ @@ -223,7 +223,7 @@ __CMPWAIT_CASE( , , 8); #undef __CMPWAIT_CASE #define __CMPWAIT_GEN(sfx) \ -static inline void __cmpwait##sfx(volatile void *ptr, \ +static __always_inline void __cmpwait##sfx(volatile void *ptr, \ unsigned long val, \ int size) \ { \ -- 2.20.1
