kernel: clean up USE_GENERIC_SMP_HELPERS

For arch which needs USE_GENERIC_SMP_HELPERS, it has to select
USE_GENERIC_SMP_HELPERS, rather than leaving a choice to user, since they
don't provide their own implementions.

Also, move on_each_cpu() to kernel/smp.c, it is strange to put it in
kernel/softirq.c.

For arch which doesn't use USE_GENERIC_SMP_HELPERS, e.g.  blackfin, only
on_each_cpu() is compiled.

Signed-off-by: Amerigo Wang <amwang@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 2 insertions, 9 deletions

diff --git a/arch/mn10300/Kconfig b/arch/mn10300/Kconfig
index 41ba38513c89..8ed41cf2b08d 100644
--- a/arch/mn10300/Kconfig
+++ b/arch/mn10300/Kconfig
@@ -203,6 +203,7 @@ endmenu
 config SMP
         bool "Symmetric multi-processing support"
         default y
+        select USE_GENERIC_SMP_HELPERS
         depends on MN10300_PROC_MN2WS0038 || MN10300_PROC_MN2WS0050
         ---help---
           This enables support for systems with more than one CPU. If you have
@@ -226,11 +227,6 @@ config NR_CPUS
         depends on SMP
         default "2"
 
-config USE_GENERIC_SMP_HELPERS
-        bool
-        depends on SMP
-        default y
-
 source "kernel/Kconfig.preempt"
 
 config MN10300_CURRENT_IN_E2
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index b6fccb07123e..8734db3c5830 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -65,6 +65,7 @@ config X86
         select HAVE_SPARSE_IRQ
         select GENERIC_IRQ_PROBE
         select GENERIC_PENDING_IRQ if SMP
+        select USE_GENERIC_SMP_HELPERS if SMP
 
 config INSTRUCTION_DECODER
         def_bool (KPROBES || PERF_EVENTS)
@@ -203,10 +204,6 @@ config HAVE_INTEL_TXT
         def_bool y
         depends on EXPERIMENTAL && DMAR && ACPI
 
-config USE_GENERIC_SMP_HELPERS
-        def_bool y
-        depends on SMP
-
 config X86_32_SMP
         def_bool y
         depends on X86_32 && SMP