[PATCH] arm64: make ll/sc __cmpxchg_case_##name asm consistent
From: mark.rutland@arm.com (Mark Rutland)
Date: 2015-08-04 16:27:34
Subsystem:
arm64 port (aarch64 architecture), atomic infrastructure, the rest · Maintainers:
Catalin Marinas, Will Deacon, Peter Zijlstra, Boqun Feng, Linus Torvalds
The ll/sc __cmpxchg_case_##name assembly mostly uses symbolic names for operands, but in a single case uses %2 to refer to what is otherwise known as %[v]. This makes the code more painful to read than is necessary. Use %[v] instead. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <redacted> --- arch/arm64/include/asm/atomic_ll_sc.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Hi Will, I spotted this on the arm64 for-next/core branch, it applies atop of "arm64: atomics: prefetch the destination word for write prior to stxr" from your armv8.1/lse branch. Mark.
diff --git a/arch/arm64/include/asm/atomic_ll_sc.h b/arch/arm64/include/asm/atomic_ll_sc.h
index 6671978..b3b5c4a 100644
--- a/arch/arm64/include/asm/atomic_ll_sc.h
+++ b/arch/arm64/include/asm/atomic_ll_sc.h@@ -181,7 +181,7 @@ __LL_SC_PREFIX(__cmpxchg_case_##name(volatile void *ptr, \ unsigned long tmp, oldval; \ \ asm volatile( \ - " prfm pstl1strm, %2\n" \ + " prfm pstl1strm, %[v]\n" \ "1: ldxr" #sz "\t%" #w "[oldval], %[v]\n" \ " eor %" #w "[tmp], %" #w "[oldval], %" #w "[old]\n" \ " cbnz %" #w "[tmp], 2f\n" \
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1.9.1