Blackfin arch: Add basic irq stack checking for Blackfin

Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>

diff --git a/arch/blackfin/Kconfig.debug b/arch/blackfin/Kconfig.debug
index 3ad2598..bfd712a 100644
--- a/arch/blackfin/Kconfig.debug
+++ b/arch/blackfin/Kconfig.debug
@@ -2,6 +2,22 @@
 
 source "lib/Kconfig.debug"
 
+config DEBUG_STACKOVERFLOW
+	bool "Check for stack overflows"
+	depends on DEBUG_KERNEL
+	help
+	  This option will cause messages to be printed if free stack space
+	  drops below a certain limit.
+
+config DEBUG_STACK_USAGE
+	bool "Enable stack utilization instrumentation"
+	depends on DEBUG_KERNEL
+	help
+	  Enables the display of the minimum amount of free stack which each
+	  task has ever had available in the sysrq-T output.
+
+	  This option will slow down process creation somewhat.
+
 config HAVE_ARCH_KGDB
        def_bool y