From 920fdab7b3ce98c14c840261e364f490f3679a62 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 10 Sep 2019 13:56:22 +0200 Subject: arm64: fix unreachable code issue with cmpxchg 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 Reported-by: Nathan Chancellor Link: https://github.com/ClangBuiltLinux/linux/issues/648 Reviewed-by: Nathan Chancellor Tested-by: Nathan Chancellor Reviewed-by: Andrew Murray Tested-by: Andrew Murray Signed-off-by: Arnd Bergmann Signed-off-by: Will Deacon --- 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 a1398f2f9994..f9bef42c1411 100644 --- a/arch/arm64/include/asm/cmpxchg.h +++ b/arch/arm64/include/asm/cmpxchg.h @@ -62,7 +62,7 @@ __XCHG_CASE( , , mb_, 64, 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) \ { \ @@ -148,7 +148,7 @@ __CMPXCHG_DBL(_mb) #undef __CMPXCHG_DBL #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) \ @@ -255,7 +255,7 @@ __CMPWAIT_CASE( , , 64); #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) \ { \ -- cgit v1.2.3-59-g8ed1b