percpu: use a kconfig variable to signal arch specific percpu setup

The use of the __GENERIC_PERCPU is a bit problematic since arches
may want to run their own percpu setup while using the generic
percpu definitions. Replace it through a kconfig variable.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

8 files changed, 14 insertions, 7 deletions

diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index 4a81b7f..5a41e75 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -80,6 +80,9 @@ config GENERIC_TIME_VSYSCALL
 	bool
 	default y
 
+config ARCH_SETS_UP_PER_CPU_AREA
+	def_bool y
+
 config DMI
 	bool
 	default y
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index c17a194..fb85f6b 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -42,6 +42,9 @@ config GENERIC_HARDIRQS
 	bool
 	default y
 
+config ARCH_SETS_UP_PER_CPU_AREA
+	def_bool PPC64
+
 config IRQ_PER_CPU
 	bool
 	default y
diff --git a/arch/sparc64/Kconfig b/arch/sparc64/Kconfig
index 1e25bce..26f5791 100644
--- a/arch/sparc64/Kconfig
+++ b/arch/sparc64/Kconfig
@@ -66,6 +66,9 @@ config AUDIT_ARCH
 	bool
 	default y
 
+config ARCH_SETS_UP_PER_CPU_AREA
+	def_bool y
+
 config ARCH_NO_VIRT_TO_BUS
 	def_bool y
 
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 1de28e8..dc80a9f 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -97,6 +97,9 @@ config GENERIC_TIME_VSYSCALL
 	bool
 	default X86_64
 
+config ARCH_SETS_UP_PER_CPU_AREA
+	def_bool X86_64
+
 config ARCH_SUPPORTS_OPROFILE
 	bool
 	default y
diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h
index d85172e..b5e53b9 100644
--- a/include/asm-generic/percpu.h
+++ b/include/asm-generic/percpu.h
@@ -3,7 +3,6 @@
 #include <linux/compiler.h>
 #include <linux/threads.h>
 
-#define __GENERIC_PER_CPU
 #ifdef CONFIG_SMP
 
 extern unsigned long __per_cpu_offset[NR_CPUS];
diff --git a/include/asm-s390/percpu.h b/include/asm-s390/percpu.h
index 545857e..f94d0d3 100644
--- a/include/asm-s390/percpu.h
+++ b/include/asm-s390/percpu.h
@@ -4,8 +4,6 @@
 #include <linux/compiler.h>
 #include <asm/lowcore.h>
 
-#define __GENERIC_PER_CPU
-
 /*
  * s390 uses its own implementation for per cpu data, the offset of
  * the cpu local data area is cached in the cpu's lowcore memory.
diff --git a/include/asm-x86/percpu_32.h b/include/asm-x86/percpu_32.h
index a7ebd43..3949586 100644
--- a/include/asm-x86/percpu_32.h
+++ b/include/asm-x86/percpu_32.h
@@ -41,8 +41,6 @@
  *    PER_CPU(cpu_gdt_descr, %ebx)
  */
 #ifdef CONFIG_SMP
-/* Same as generic implementation except for optimized local access. */
-#define __GENERIC_PER_CPU
 
 /* This is used for other cpus to find our section. */
 extern unsigned long __per_cpu_offset[];
diff --git a/init/main.c b/init/main.c
index f287ca5..3f8aba2 100644
--- a/init/main.c
+++ b/init/main.c
@@ -363,7 +363,7 @@ static inline void smp_prepare_cpus(unsigned int maxcpus) { }
 
 #else
 
-#ifdef __GENERIC_PER_CPU
+#ifndef CONFIG_ARCH_SETS_UP_PER_CPU_AREA
 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
 
 EXPORT_SYMBOL(__per_cpu_offset);
@@ -384,7 +384,7 @@ static void __init setup_per_cpu_areas(void)
 		ptr += size;
 	}
 }
-#endif /* !__GENERIC_PER_CPU */
+#endif /* CONFIG_ARCH_SETS_UP_CPU_AREA */
 
 /* Called by boot processor to activate the rest. */
 static void __init smp_init(void)