riscv/atomic.h: use RISCV_FULL_BARRIER in _arch_atomic* function.

Replace the same code with the pre-defined macro
RISCV_FULL_BARRIER to simplify the code.

Signed-off-by: Zongmin Zhou <zhouzongmin@kylinos.cn>
Link: https://patch.msgid.link/20251120095831.64211-1-min_halo@163.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>

Author: Zongmin Zhou

arch/riscv/include/asm/atomic.h

@@ -203,7 +203,7 @@ ATOMIC_OPS(xor, xor, i)
 		"	add            %[rc], %[p], %[a]\n"		\
 		"	sc." sfx ".rl  %[rc], %[rc], %[c]\n"		\
 		"	bnez           %[rc], 0b\n"			\
-		"	fence          rw, rw\n"			\
+		RISCV_FULL_BARRIER					\
 		"1:\n"							\
 		: [p]"=&r" (_prev), [rc]"=&r" (_rc), [c]"+A" (counter)	\
 		: [a]"r" (_a), [u]"r" (_u)				\
@@ -242,7 +242,7 @@ static __always_inline s64 arch_atomic64_fetch_add_unless(atomic64_t *v, s64 a,
 		"	addi            %[rc], %[p], 1\n"		\
 		"	sc." sfx ".rl   %[rc], %[rc], %[c]\n"		\
 		"	bnez            %[rc], 0b\n"			\
-		"	fence           rw, rw\n"			\
+		RISCV_FULL_BARRIER					\
 		"1:\n"							\
 		: [p]"=&r" (_prev), [rc]"=&r" (_rc), [c]"+A" (counter)	\
 		:							\
@@ -268,7 +268,7 @@ static __always_inline bool arch_atomic_inc_unless_negative(atomic_t *v)
 		"	addi            %[rc], %[p], -1\n"		\
 		"	sc." sfx ".rl   %[rc], %[rc], %[c]\n"		\
 		"	bnez            %[rc], 0b\n"			\
-		"	fence           rw, rw\n"			\
+		RISCV_FULL_BARRIER					\
 		"1:\n"							\
 		: [p]"=&r" (_prev), [rc]"=&r" (_rc), [c]"+A" (counter)	\
 		:							\
@@ -294,7 +294,7 @@ static __always_inline bool arch_atomic_dec_unless_positive(atomic_t *v)
 		"	bltz           %[rc], 1f\n"			\
 		"	sc." sfx ".rl  %[rc], %[rc], %[c]\n"		\
 		"	bnez           %[rc], 0b\n"			\
-		"	fence          rw, rw\n"			\
+		RISCV_FULL_BARRIER					\
 		"1:\n"							\
 		: [p]"=&r" (_prev), [rc]"=&r" (_rc), [c]"+A" (counter)	\
 		:							\