From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Mon, 6 Aug 2018 15:17:44 +0200 From: Vasily Gorbik Subject: [PATCH 2/4] trace: avoid calling cc-option -mrecord-mcount for every Makefile References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Message-Id: Sender: linux-kbuild-owner@vger.kernel.org List-Archive: List-Post: To: Masahiro Yamada , Michal Marek , Martin Schwidefsky , Heiko Carstens , Steven Rostedt , Ingo Molnar Cc: linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, Andi Kleen List-ID: Currently if CONFIG_FTRACE_MCOUNT_RECORD is enabled -mrecord-mcount compiler flag support is tested for every Makefile. Top 4 cc-option usages: 511 -mrecord-mcount 11 -fno-stack-protector 9 -Wno-override-init 2 -fsched-pressure To address that move cc-option from scripts/Makefile.build to top Makefile and export CC_USING_RECORD_MCOUNT to be used in original place. While doing that also add -mrecord-mcount to CC_FLAGS_FTRACE (if gcc actually supports it). Signed-off-by: Vasily Gorbik --- Makefile | 7 +++++++ scripts/Makefile.build | 9 +++------ 2 files changed, 10 insertions(+), 6 deletions(-) diff --git a/Makefile b/Makefile index 503f533277c7..621ebdbfbf89 100644 --- a/Makefile +++ b/Makefile @@ -743,6 +743,13 @@ ifdef CONFIG_FUNCTION_TRACER ifndef CC_FLAGS_FTRACE CC_FLAGS_FTRACE := -pg endif +ifdef CONFIG_FTRACE_MCOUNT_RECORD + # gcc 5 supports generating the mcount tables directly + ifeq ($(call cc-option-yn,-mrecord-mcount),y) + CC_FLAGS_FTRACE += -mrecord-mcount + export CC_USING_RECORD_MCOUNT := 1 + endif +endif ifdef CONFIG_HAVE_FENTRY ifeq ($(call cc-option-yn, -mfentry),y) CC_FLAGS_FTRACE += -mfentry diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 514ed63ff571..42ecb8cf7666 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -206,11 +206,8 @@ cmd_modversions_c = \ endif ifdef CONFIG_FTRACE_MCOUNT_RECORD -# gcc 5 supports generating the mcount tables directly -ifneq ($(call cc-option,-mrecord-mcount,y),y) -KBUILD_CFLAGS += -mrecord-mcount -else -# else do it all manually +ifndef CC_USING_RECORD_MCOUNT +# compiler will not generate __mcount_loc use recordmcount or recordmcount.pl ifdef BUILD_C_RECORDMCOUNT ifeq ("$(origin RECORDMCOUNT_WARN)", "command line") RECORDMCOUNT_FLAGS = -w @@ -239,7 +236,7 @@ cmd_record_mcount = \ "$(CC_FLAGS_FTRACE)" ]; then \ $(sub_cmd_record_mcount) \ fi; -endif # -record-mcount +endif # CC_USING_RECORD_MCOUNT endif # CONFIG_FTRACE_MCOUNT_RECORD ifdef CONFIG_STACK_VALIDATION -- 2.18.0.13.gd42ae10