* Makefile:
- globally use -mprofile-kernel in case it's configured,
available and bug-free.
* arch/powerpc/gcc-mprofile-kernel-notrace.sh:
- make sure -mprofile-kernel works and has none of the
known bugs.
* arch/powerpc/kernel/ftrace.c:
- error out on compile with HAVE_DYNAMIC_FTRACE_WITH_REGS
and a buggy compiler.
* arch/powerpc/Kconfig / kernel/trace/Kconfig:
- declare that ppc64le HAVE_MPROFILE_KERNEL and
HAVE_DYNAMIC_FTRACE_WITH_REGS, and use it.
Signed-off-by: Torsten Duwe <duwe@xxxxxxx>
---
arch/powerpc/Kconfig | 2 ++
arch/powerpc/Makefile | 17 +++++++++++++++
arch/powerpc/gcc-mprofile-kernel-notrace.sh | 33 +++++++++++++++++++++++++++++
arch/powerpc/kernel/ftrace.c | 5 +++++
kernel/trace/Kconfig | 5 +++++
5 files changed, 62 insertions(+)
create mode 100755 arch/powerpc/gcc-mprofile-kernel-notrace.sh
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index e4824fd..e5f288c 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -94,8 +94,10 @@ config PPC
select OF_RESERVED_MEM
select HAVE_FTRACE_MCOUNT_RECORD
select HAVE_DYNAMIC_FTRACE
+ select HAVE_DYNAMIC_FTRACE_WITH_REGS if PPC64 && CPU_LITTLE_ENDIAN
select HAVE_FUNCTION_TRACER
select HAVE_FUNCTION_GRAPH_TRACER
+ select HAVE_MPROFILE_KERNEL if PPC64 && CPU_LITTLE_ENDIAN
select SYSCTL_EXCEPTION_TRACE
select ARCH_WANT_OPTIONAL_GPIOLIB
select VIRT_TO_BUS if !PPC64
diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index 96efd82..08a3952 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -133,6 +133,23 @@ else
CFLAGS-$(CONFIG_GENERIC_CPU) += -mcpu=powerpc64
endif
+ifeq ($(CONFIG_PPC64),y)
+ifdef CONFIG_HAVE_MPROFILE_KERNEL
+
+ifdef CONFIG_DYNAMIC_FTRACE
+ifeq ($(shell $(CONFIG_SHELL) $(srctree)/arch/powerpc/gcc-mprofile-kernel-notrace.sh $(CC) -I$(srctree)/include -D__KERNEL__), y)
+CC_USING_MPROFILE_KERNEL := -mprofile-kernel
+endif
+endif
+
+ifdef CC_USING_MPROFILE_KERNEL
+CC_FLAGS_FTRACE := -pg $(CC_USING_MPROFILE_KERNEL)
+KBUILD_CPPFLAGS += -DCC_USING_MPROFILE_KERNEL
+endif
+
+endif
+endif
+
CFLAGS-$(CONFIG_CELL_CPU) += $(call cc-option,-mcpu=cell)
CFLAGS-$(CONFIG_POWER4_CPU) += $(call cc-option,-mcpu=power4)
CFLAGS-$(CONFIG_POWER5_CPU) += $(call cc-option,-mcpu=power5)
diff --git a/arch/powerpc/gcc-mprofile-kernel-notrace.sh b/arch/powerpc/gcc-mprofile-kernel-notrace.sh
new file mode 100755
index 0000000..68d6482
--- /dev/null
+++ b/arch/powerpc/gcc-mprofile-kernel-notrace.sh
@@ -0,0 +1,33 @@
+#!/bin/sh
+# Test whether the compile option -mprofile-kernel
+# generates profiling code ( = a call to mcount), and
+# whether a function without any global references sets
+# the TOC pointer properly at the beginning, and
+# whether the "notrace" function attribute successfully
+# suppresses the _mcount call.
+
+echo "int func() { return 0; }" | \
+ $* -S -x c -O2 -p -mprofile-kernel - -o - 2> /dev/null | \
+ grep -q "mcount"
+
+trace_result=$?
+
+echo "int func() { return 0; }" | \
+ $* -S -x c -O2 -p -mprofile-kernel - -o - 2> /dev/null | \
+ sed -n -e '/func:/,/bl _mcount/p' | grep -q TOC
+
+leaf_toc_result=$?
+
+/bin/echo -e "#include <linux/compiler.h>\nnotrace int func() { return 0; }" | \
+ $* -S -x c -O2 -p -mprofile-kernel - -o - 2> /dev/null | \
+ grep -q "mcount"
+
+notrace_result=$?
+
+if [ "$trace_result" -eq "0" -a \
+ "$leaf_toc_result" -eq "0" -a \
+ "$notrace_result" -eq "1" ]; then
+ echo y
+else
+ echo n
+fi
diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c
index ef8b916..29b7014 100644
--- a/arch/powerpc/kernel/ftrace.c
+++ b/arch/powerpc/kernel/ftrace.c
@@ -28,6 +28,11 @@
#ifdef CONFIG_DYNAMIC_FTRACE
+#if defined(CONFIG_DYNAMIC_FTRACE_WITH_REGS) && defined(CONFIG_PPC64) && \
+ !defined(CC_USING_MPROFILE_KERNEL)
+#error "DYNAMIC_FTRACE_WITH_REGS requires working -mprofile-kernel"
+#endif
+
static unsigned int
ftrace_call_replace(unsigned long ip, unsigned long addr, int link)
{
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index e45db6b..a138f6d 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -52,6 +52,11 @@ config HAVE_FENTRY
help
Arch supports the gcc options -pg with -mfentry
+config HAVE_MPROFILE_KERNEL
+ bool
+ help
+ Arch supports the gcc options -pg with -mprofile-kernel
+
config HAVE_C_RECORDMCOUNT
bool
help
--
1.8.5.6
--
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