ARM: ftrace: enable function graph tracer
Add the options to enable the function graph tracer on ARM. Function
graph tracer support requires frame pointers, so exclude Thumb-2 and
also make sure FRAME_POINTER gets enabled when FUNCTION_GRAPH_TRACER is
used, since FUNCTION_TRACER doesn't "select FRAME_POINTER" when
ARM_UNWIND is used. Therefore, with GCC 4.4.0+, you get plain function
tracing without frame pointers, but you'll need them if you want
function graph tracing.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Rabin Vincent <rabin@rab.in>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 8ae3d48..bd620a4 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -14,6 +14,7 @@
select HAVE_FUNCTION_TRACER if (!XIP_KERNEL)
select HAVE_FTRACE_MCOUNT_RECORD if (!XIP_KERNEL)
select HAVE_DYNAMIC_FTRACE if (!XIP_KERNEL)
+ select HAVE_FUNCTION_GRAPH_TRACER if (!THUMB2_KERNEL)
select HAVE_GENERIC_DMA_COHERENT
select HAVE_KERNEL_GZIP
select HAVE_KERNEL_LZO
diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug
index 2fd0b99..eac6208 100644
--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug
@@ -23,7 +23,7 @@
config FRAME_POINTER
bool
depends on !THUMB2_KERNEL
- default y if !ARM_UNWIND
+ default y if !ARM_UNWIND || FUNCTION_GRAPH_TRACER
help
If you say N here, the resulting kernel will be slightly smaller and
faster. However, if neither FRAME_POINTER nor ARM_UNWIND are enabled,