percpu: implement optional weak percpu definitions

[safe/jmp/linux-2.6] / lib / Kconfig.debug

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 23067ab..77e0d8b 100644 (file)
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -777,6 +777,21 @@ config DEBUG_BLOCK_EXT_DEVT
 
          Say N if you are unsure.
 
+config DEBUG_FORCE_WEAK_PER_CPU
+       bool "Force weak per-cpu definitions"
+       depends on DEBUG_KERNEL
+       help
+         s390 and alpha require percpu variables in modules to be
+         defined weak to work around addressing range issue which
+         puts the following two restrictions on percpu variable
+         definitions.
+
+         1. percpu symbols must be unique whether static or not
+         2. percpu variables can't be defined inside a function
+
+         To ensure that generic code follows the above rules, this
+         option forces all percpu variables to be defined as weak.
+
 config LKDTM
        tristate "Linux Kernel Dump Test Tool Module"
        depends on DEBUG_KERNEL