atomic64_test: simplify the #ifdef for atomic64_dec_if_positive() test

Introduce CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE and use this instead
of the multitude of #if defined() checks in atomic64_test.c

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index fbdd853..4172c3c 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -11,6 +11,7 @@
 	select RTC_LIB
 	select SYS_SUPPORTS_APM_EMULATION
 	select GENERIC_ATOMIC64 if (CPU_V6 || !CPU_32v6K || !AEABI)
+	select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
 	select HAVE_OPROFILE if (HAVE_PERF_EVENTS)
 	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
 	select HAVE_ARCH_KGDB
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index b3e10fd..5e238d03 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -20,6 +20,7 @@
 	select ARCH_BINFMT_ELF_RANDOMIZE_PIE
 	select RTC_LIB if !MACH_LOONGSON
 	select GENERIC_ATOMIC64 if !64BIT
+	select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
 	select HAVE_DMA_ATTRS
 	select HAVE_DMA_API_DEBUG
 	select HAVE_GENERIC_HARDIRQS
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 9a5d3cd..4f681b7 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -115,6 +115,7 @@
 	select HAVE_OPROFILE
 	select HAVE_SYSCALL_WRAPPERS if PPC64
 	select GENERIC_ATOMIC64 if PPC32
+	select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
 	select HAVE_IRQ_WORK
 	select HAVE_PERF_EVENTS
 	select HAVE_REGS_AND_STACK_ACCESS_API
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index a39b469..d0a5e92 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -85,6 +85,7 @@
 	select HAVE_ARCH_MUTEX_CPU_RELAX
 	select HAVE_ARCH_JUMP_LABEL if !MARCH_G5
 	select ARCH_SAVE_PAGE_KEYS if HIBERNATION
+	select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
 	select HAVE_MEMBLOCK
 	select HAVE_MEMBLOCK_NODE_MAP
 	select HAVE_CMPXCHG_LOCAL
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index c70684f..ca4fdef 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -70,6 +70,7 @@
 	select HAVE_ARCH_JUMP_LABEL
 	select HAVE_TEXT_POKE_SMP
 	select HAVE_GENERIC_HARDIRQS
+	select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
 	select SPARSE_IRQ
 	select GENERIC_FIND_FIRST_BIT
 	select GENERIC_IRQ_PROBE
diff --git a/lib/Kconfig b/lib/Kconfig
index 8269d56..72c1d46 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -340,6 +340,9 @@
 config GENERIC_ATOMIC64
        bool
 
+config ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
+	def_bool y if GENERIC_ATOMIC64
+
 config LRU_CACHE
 	tristate
 
diff --git a/lib/atomic64_test.c b/lib/atomic64_test.c
index cb99b91..00bca22 100644
--- a/lib/atomic64_test.c
+++ b/lib/atomic64_test.c
@@ -114,8 +114,7 @@
 	r += one;
 	BUG_ON(v.counter != r);
 
-#if defined(CONFIG_X86) || defined(CONFIG_MIPS) || defined(CONFIG_PPC) || \
-    defined(CONFIG_S390) || defined(_ASM_GENERIC_ATOMIC64_H) || defined(CONFIG_ARM)
+#ifdef CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
 	INIT(onestwos);
 	BUG_ON(atomic64_dec_if_positive(&v) != (onestwos - 1));
 	r -= one;
@@ -129,7 +128,7 @@
 	BUG_ON(atomic64_dec_if_positive(&v) != (-one - one));
 	BUG_ON(v.counter != r);
 #else
-#warning Please implement atomic64_dec_if_positive for your architecture, and add it to the IF above
+#warning Please implement atomic64_dec_if_positive for your architecture and select the above Kconfig symbol
 #endif
 
 	INIT(onestwos);