From e0d5896bd356cd577f9710a02d7a474cdf58426b Mon Sep 17 00:00:00 2001 From: Sami Tolvanen Date: Thu, 31 Oct 2019 12:57:05 -0700 Subject: [PATCH] arm64: lse: fix LSE atomics with LLVM's integrated assembler Unlike gcc, clang considers each inline assembly block to be independent and therefore, when using the integrated assembler for inline assembly, any preambles that enable features must be repeated in each block. This change defines __LSE_PREAMBLE and adds it to each inline assembly block that has LSE instructions, which allows them to be compiled also with clang's assembler. Link: https://github.com/ClangBuiltLinux/linux/issues/671 Signed-off-by: Sami Tolvanen Tested-by: Andrew Murray Tested-by: Kees Cook Reviewed-by: Andrew Murray Reviewed-by: Kees Cook Reviewed-by: Nick Desaulniers Signed-off-by: Will Deacon --- arch/arm64/include/asm/atomic_lse.h | 19 +++++++++++++++++++ arch/arm64/include/asm/lse.h | 6 +++--- 2 files changed, 22 insertions(+), 3 deletions(-) diff --git a/arch/arm64/include/asm/atomic_lse.h b/arch/arm64/include/asm/atomic_lse.h index 574808b9df4c..da3280f639cd 100644 --- a/arch/arm64/include/asm/atomic_lse.h +++ b/arch/arm64/include/asm/atomic_lse.h @@ -14,6 +14,7 @@ static inline void __lse_atomic_##op(int i, atomic_t *v) \ { \ asm volatile( \ + __LSE_PREAMBLE \ " " #asm_op " %w[i], %[v]\n" \ : [i] "+r" (i), [v] "+Q" (v->counter) \ : "r" (v)); \ @@ -30,6 +31,7 @@ ATOMIC_OP(add, stadd) static inline int __lse_atomic_fetch_##op##name(int i, atomic_t *v) \ { \ asm volatile( \ + __LSE_PREAMBLE \ " " #asm_op #mb " %w[i], %w[i], %[v]" \ : [i] "+r" (i), [v] "+Q" (v->counter) \ : "r" (v) \ @@ -58,6 +60,7 @@ static inline int __lse_atomic_add_return##name(int i, atomic_t *v) \ u32 tmp; \ \ asm volatile( \ + __LSE_PREAMBLE \ " ldadd" #mb " %w[i], %w[tmp], %[v]\n" \ " add %w[i], %w[i], %w[tmp]" \ : [i] "+r" (i), [v] "+Q" (v->counter), [tmp] "=&r" (tmp) \ @@ -77,6 +80,7 @@ ATOMIC_OP_ADD_RETURN( , al, "memory") static inline void __lse_atomic_and(int i, atomic_t *v) { asm volatile( + __LSE_PREAMBLE " mvn %w[i], %w[i]\n" " stclr %w[i], %[v]" : [i] "+&r" (i), [v] "+Q" (v->counter) @@ -87,6 +91,7 @@ static inline void __lse_atomic_and(int i, atomic_t *v) static inline int __lse_atomic_fetch_and##name(int i, atomic_t *v) \ { \ asm volatile( \ + __LSE_PREAMBLE \ " mvn %w[i], %w[i]\n" \ " ldclr" #mb " %w[i], %w[i], %[v]" \ : [i] "+&r" (i), [v] "+Q" (v->counter) \ @@ -106,6 +111,7 @@ ATOMIC_FETCH_OP_AND( , al, "memory") static inline void __lse_atomic_sub(int i, atomic_t *v) { asm volatile( + __LSE_PREAMBLE " neg %w[i], %w[i]\n" " stadd %w[i], %[v]" : [i] "+&r" (i), [v] "+Q" (v->counter) @@ -118,6 +124,7 @@ static inline int __lse_atomic_sub_return##name(int i, atomic_t *v) \ u32 tmp; \ \ asm volatile( \ + __LSE_PREAMBLE \ " neg %w[i], %w[i]\n" \ " ldadd" #mb " %w[i], %w[tmp], %[v]\n" \ " add %w[i], %w[i], %w[tmp]" \ @@ -139,6 +146,7 @@ ATOMIC_OP_SUB_RETURN( , al, "memory") static inline int __lse_atomic_fetch_sub##name(int i, atomic_t *v) \ { \ asm volatile( \ + __LSE_PREAMBLE \ " neg %w[i], %w[i]\n" \ " ldadd" #mb " %w[i], %w[i], %[v]" \ : [i] "+&r" (i), [v] "+Q" (v->counter) \ @@ -159,6 +167,7 @@ ATOMIC_FETCH_OP_SUB( , al, "memory") static inline void __lse_atomic64_##op(s64 i, atomic64_t *v) \ { \ asm volatile( \ + __LSE_PREAMBLE \ " " #asm_op " %[i], %[v]\n" \ : [i] "+r" (i), [v] "+Q" (v->counter) \ : "r" (v)); \ @@ -175,6 +184,7 @@ ATOMIC64_OP(add, stadd) static inline long __lse_atomic64_fetch_##op##name(s64 i, atomic64_t *v)\ { \ asm volatile( \ + __LSE_PREAMBLE \ " " #asm_op #mb " %[i], %[i], %[v]" \ : [i] "+r" (i), [v] "+Q" (v->counter) \ : "r" (v) \ @@ -203,6 +213,7 @@ static inline long __lse_atomic64_add_return##name(s64 i, atomic64_t *v)\ unsigned long tmp; \ \ asm volatile( \ + __LSE_PREAMBLE \ " ldadd" #mb " %[i], %x[tmp], %[v]\n" \ " add %[i], %[i], %x[tmp]" \ : [i] "+r" (i), [v] "+Q" (v->counter), [tmp] "=&r" (tmp) \ @@ -222,6 +233,7 @@ ATOMIC64_OP_ADD_RETURN( , al, "memory") static inline void __lse_atomic64_and(s64 i, atomic64_t *v) { asm volatile( + __LSE_PREAMBLE " mvn %[i], %[i]\n" " stclr %[i], %[v]" : [i] "+&r" (i), [v] "+Q" (v->counter) @@ -232,6 +244,7 @@ static inline void __lse_atomic64_and(s64 i, atomic64_t *v) static inline long __lse_atomic64_fetch_and##name(s64 i, atomic64_t *v) \ { \ asm volatile( \ + __LSE_PREAMBLE \ " mvn %[i], %[i]\n" \ " ldclr" #mb " %[i], %[i], %[v]" \ : [i] "+&r" (i), [v] "+Q" (v->counter) \ @@ -251,6 +264,7 @@ ATOMIC64_FETCH_OP_AND( , al, "memory") static inline void __lse_atomic64_sub(s64 i, atomic64_t *v) { asm volatile( + __LSE_PREAMBLE " neg %[i], %[i]\n" " stadd %[i], %[v]" : [i] "+&r" (i), [v] "+Q" (v->counter) @@ -263,6 +277,7 @@ static inline long __lse_atomic64_sub_return##name(s64 i, atomic64_t *v) \ unsigned long tmp; \ \ asm volatile( \ + __LSE_PREAMBLE \ " neg %[i], %[i]\n" \ " ldadd" #mb " %[i], %x[tmp], %[v]\n" \ " add %[i], %[i], %x[tmp]" \ @@ -284,6 +299,7 @@ ATOMIC64_OP_SUB_RETURN( , al, "memory") static inline long __lse_atomic64_fetch_sub##name(s64 i, atomic64_t *v) \ { \ asm volatile( \ + __LSE_PREAMBLE \ " neg %[i], %[i]\n" \ " ldadd" #mb " %[i], %[i], %[v]" \ : [i] "+&r" (i), [v] "+Q" (v->counter) \ @@ -305,6 +321,7 @@ static inline s64 __lse_atomic64_dec_if_positive(atomic64_t *v) unsigned long tmp; asm volatile( + __LSE_PREAMBLE "1: ldr %x[tmp], %[v]\n" " subs %[ret], %x[tmp], #1\n" " b.lt 2f\n" @@ -332,6 +349,7 @@ __lse__cmpxchg_case_##name##sz(volatile void *ptr, \ unsigned long tmp; \ \ asm volatile( \ + __LSE_PREAMBLE \ " mov %" #w "[tmp], %" #w "[old]\n" \ " cas" #mb #sfx "\t%" #w "[tmp], %" #w "[new], %[v]\n" \ " mov %" #w "[ret], %" #w "[tmp]" \ @@ -379,6 +397,7 @@ __lse__cmpxchg_double##name(unsigned long old1, \ register unsigned long x4 asm ("x4") = (unsigned long)ptr; \ \ asm volatile( \ + __LSE_PREAMBLE \ " casp" #mb "\t%[old1], %[old2], %[new1], %[new2], %[v]\n"\ " eor %[old1], %[old1], %[oldval1]\n" \ " eor %[old2], %[old2], %[oldval2]\n" \ diff --git a/arch/arm64/include/asm/lse.h b/arch/arm64/include/asm/lse.h index 80b388278149..73834996c4b6 100644 --- a/arch/arm64/include/asm/lse.h +++ b/arch/arm64/include/asm/lse.h @@ -6,6 +6,8 @@ #if defined(CONFIG_AS_LSE) && defined(CONFIG_ARM64_LSE_ATOMICS) +#define __LSE_PREAMBLE ".arch armv8-a+lse\n" + #include #include #include @@ -14,8 +16,6 @@ #include #include -__asm__(".arch_extension lse"); - extern struct static_key_false cpu_hwcap_keys[ARM64_NCAPS]; extern struct static_key_false arm64_const_caps_ready; @@ -34,7 +34,7 @@ static inline bool system_uses_lse_atomics(void) /* In-line patching at runtime */ #define ARM64_LSE_ATOMIC_INSN(llsc, lse) \ - ALTERNATIVE(llsc, lse, ARM64_HAS_LSE_ATOMICS) + ALTERNATIVE(llsc, __LSE_PREAMBLE lse, ARM64_HAS_LSE_ATOMICS) #else /* CONFIG_AS_LSE && CONFIG_ARM64_LSE_ATOMICS */