From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from newverein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id A8B931A03E6 for ; Thu, 11 Feb 2016 04:44:53 +1100 (AEDT) In-Reply-To: <20160210174221.EBBEC692C8@newverein.lst.de> References: <20160210174221.EBBEC692C8@newverein.lst.de> From: Torsten Duwe Date: Wed, 10 Feb 2016 17:25:01 +0100 Subject: [PATCH v8 4/8] ppc64 ftrace_with_regs configuration variables To: Michael Ellerman Cc: Jiri Kosina , Miroslav Benes , Petr Mladek , Jessica Yu , Steven Rostedt , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, live-patching@vger.kernel.org Message-Id: <20160210174450.9C065692C8@newverein.lst.de> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , * arch/powerpc/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 --- 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 \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