[ARM] 5386/2: unwind: Add Makefile and Kconfig entries for ARM stack unwinding
This patch also makes the frame pointer default to y only if
!ARM_UNWIND. LOCKDEP no longer selects FRAME_POINTER if ARM_UNWIND is
enabled.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
index 192ee01..35f8db3 100644
--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug
@@ -2,18 +2,29 @@
source "lib/Kconfig.debug"
-# RMK wants arm kernels compiled with frame pointers so hardwire this to y.
+# RMK wants arm kernels compiled with frame pointers or stack unwinding.
# If you know what you are doing and are willing to live without stack
# traces, you can get a slightly smaller kernel by setting this option to
# n, but then RMK will have to kill you ;).
config FRAME_POINTER
bool
- default y
+ default y if !ARM_UNWIND
help
If you say N here, the resulting kernel will be slightly smaller and
- faster. However, when a problem occurs with the kernel, the
- information that is reported is severely limited. Most people
- should say Y here.
+ faster. However, if neither FRAME_POINTER nor ARM_UNWIND are enabled,
+ when a problem occurs with the kernel, the information that is
+ reported is severely limited.
+
+config ARM_UNWIND
+ bool "Enable stack unwinding support"
+ depends on AEABI && EXPERIMENTAL
+ default y
+ help
+ This option enables stack unwinding support in the kernel
+ using the information automatically generated by the
+ compiler. The resulting kernel image is slightly bigger but
+ the performance is not affected. Currently, this feature
+ only works with EABI compilers. If unsure say Y.
config DEBUG_USER
bool "Verbose user fault messages"
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index 24e0f01..e7ef876e 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -85,6 +85,10 @@
CFLAGS_ABI :=$(call cc-option,-mapcs-32,-mabi=apcs-gnu) $(call cc-option,-mno-thumb-interwork,)
endif
+ifeq ($(CONFIG_ARM_UNWIND),y)
+CFLAGS_ABI +=-funwind-tables
+endif
+
# Need -Uarm for gcc < 3.x
KBUILD_CFLAGS +=$(CFLAGS_ABI) $(arch-y) $(tune-y) $(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,)) -msoft-float -Uarm
KBUILD_AFLAGS +=$(CFLAGS_ABI) $(arch-y) $(tune-y) -msoft-float
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index 4305345..ca60d33 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -29,6 +29,7 @@
obj-$(CONFIG_OABI_COMPAT) += sys_oabi-compat.o
obj-$(CONFIG_ARM_THUMBEE) += thumbee.o
obj-$(CONFIG_KGDB) += kgdb.o
+obj-$(CONFIG_ARM_UNWIND) += unwind.o
obj-$(CONFIG_CRUNCH) += crunch.o crunch-bits.o
AFLAGS_crunch-bits.o := -Wa,-mcpu=ep9312