Add an assembly macro to refer runtime cost. It hides linker magic and
makes assembly more readable.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
---
arch/x86/include/asm/runtime-const.h | 13 +++++++++++++
arch/x86/lib/getuser.S | 7 ++-----
2 files changed, 15 insertions(+), 5 deletions(-)
diff --git a/arch/x86/include/asm/runtime-const.h b/arch/x86/include/asm/runtime-const.h
index 6652ebddfd02..8d983cfd06ea 100644
--- a/arch/x86/include/asm/runtime-const.h
+++ b/arch/x86/include/asm/runtime-const.h
@@ -2,6 +2,18 @@
#ifndef _ASM_RUNTIME_CONST_H
#define _ASM_RUNTIME_CONST_H
+#ifdef __ASSEMBLY__
+
+.macro RUNTIME_CONST_PTR sym reg
+ movq $0x0123456789abcdef, %\reg
+ 1:
+ .pushsection runtime_ptr_\sym, "a"
+ .long 1b - 8 - .
+ .popsection
+.endm
+
+#else /* __ASSEMBLY__ */
+
#define runtime_const_ptr(sym) ({ \
typeof(sym) __ret; \
asm_inline("mov %1,%0\n1:\n" \
@@ -58,4 +70,5 @@ static inline void runtime_const_fixup(void (*fn)(void *, unsigned long),
}
}
+#endif /* __ASSEMBLY__ */
#endif
diff --git a/arch/x86/lib/getuser.S b/arch/x86/lib/getuser.S
index 4357ec2a0bfc..49ddb563e9e3 100644
--- a/arch/x86/lib/getuser.S
+++ b/arch/x86/lib/getuser.S
@@ -34,16 +34,13 @@
#include <asm/thread_info.h>
#include <asm/asm.h>
#include <asm/smap.h>
+#include <asm/runtime-const.h>
#define ASM_BARRIER_NOSPEC ALTERNATIVE "", "lfence", X86_FEATURE_LFENCE_RDTSC
.macro check_range size:req
.if IS_ENABLED(CONFIG_X86_64)
- movq $0x0123456789abcdef,%rdx
- 1:
- .pushsection runtime_ptr_USER_PTR_MAX,"a"
- .long 1b - 8 - .
- .popsection
+ RUNTIME_CONST_PTR USER_PTR_MAX, rdx
cmp %rax, %rdx
sbb %rdx, %rdx
or %rdx, %rax
--
2.45.2