From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ex13-edg-ou-001.vmware.com ([208.91.0.189]:45001 "EHLO EX13-EDG-OU-001.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725799AbeJDEWl (ORCPT ); Thu, 4 Oct 2018 00:22:41 -0400 From: Nadav Amit Subject: [PATCH v9 02/10] Makefile: Prepare for using macros for inline asm Date: Wed, 3 Oct 2018 14:30:52 -0700 Message-ID: <20181003213100.189959-3-namit@vmware.com> In-Reply-To: <20181003213100.189959-1-namit@vmware.com> References: <20181003213100.189959-1-namit@vmware.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, x86@kernel.org, Nadav Amit , Sam Ravnborg , Michal Marek , Thomas Gleixner , "H. Peter Anvin" , linux-kbuild@vger.kernel.org Using macros for inline assembly improves both readability and compilation decisions that are distorted by big assembly blocks that use alternative sections. Compile macros.S and use it to assemble all C files. Currently, only x86 will use it. Cc: Sam Ravnborg Cc: Michal Marek Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: x86@kernel.org Cc: linux-kbuild@vger.kernel.org Acked-by: Masahiro Yamada Acked-by: Peter Zijlstra (Intel) Tested-by: Kees Cook Signed-off-by: Nadav Amit --- Makefile | 9 +++++++-- arch/x86/Makefile | 7 +++++++ arch/x86/kernel/macros.S | 7 +++++++ scripts/Kbuild.include | 4 +++- scripts/mod/Makefile | 2 ++ 5 files changed, 26 insertions(+), 3 deletions(-) create mode 100644 arch/x86/kernel/macros.S diff --git a/Makefile b/Makefile index 6c3da3e10f07..6c40d547513c 100644 --- a/Makefile +++ b/Makefile @@ -1071,7 +1071,7 @@ scripts: scripts_basic asm-generic gcc-plugins $(autoksyms_h) # version.h and scripts_basic is processed / created. # Listed in dependency order -PHONY += prepare archprepare prepare0 prepare1 prepare2 prepare3 +PHONY += prepare archprepare macroprepare prepare0 prepare1 prepare2 prepare3 # prepare3 is used to check if we are building in a separate output directory, # and if so do: @@ -1094,7 +1094,9 @@ prepare2: prepare3 outputmakefile asm-generic prepare1: prepare2 $(version_h) $(autoksyms_h) include/generated/utsrelease.h $(cmd_crmodverdir) -archprepare: archheaders archscripts prepare1 scripts_basic +macroprepare: prepare1 archmacros + +archprepare: archheaders archscripts macroprepare scripts_basic prepare0: archprepare gcc-plugins $(Q)$(MAKE) $(build)=. @@ -1162,6 +1164,9 @@ archheaders: PHONY += archscripts archscripts: +PHONY += archmacros +archmacros: + PHONY += __headers __headers: $(version_h) scripts_basic uapi-asm-generic archheaders archscripts $(Q)$(MAKE) $(build)=scripts build_unifdef diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 8f6e7eb8ae9f..18a0084f134b 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -237,6 +237,13 @@ archscripts: scripts_basic archheaders: $(Q)$(MAKE) $(build)=arch/x86/entry/syscalls all +archmacros: + $(Q)$(MAKE) $(build)=arch/x86/kernel arch/x86/kernel/macros.s + +ASM_MACRO_FLAGS = -Wa,arch/x86/kernel/macros.s -Wa,- +export ASM_MACRO_FLAGS +KBUILD_CFLAGS += $(ASM_MACRO_FLAGS) + ### # Kernel objects diff --git a/arch/x86/kernel/macros.S b/arch/x86/kernel/macros.S new file mode 100644 index 000000000000..cfc1c7d1a6eb --- /dev/null +++ b/arch/x86/kernel/macros.S @@ -0,0 +1,7 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* + * This file includes headers whose assembly part includes macros which are + * commonly used. The macros are precompiled into assmebly file which is later + * assembled together with each compiled file. + */ diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index ce53639a864a..8aeb60eb6ee3 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -115,7 +115,9 @@ __cc-option = $(call try-run,\ # Do not attempt to build with gcc plugins during cc-option tests. # (And this uses delayed resolution so the flags will be up to date.) -CC_OPTION_CFLAGS = $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS)) +# In addition, do not include the asm macros which are built later. +CC_OPTION_FILTERED = $(GCC_PLUGINS_CFLAGS) $(ASM_MACRO_FLAGS) +CC_OPTION_CFLAGS = $(filter-out $(CC_OPTION_FILTERED),$(KBUILD_CFLAGS)) # cc-option # Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586) diff --git a/scripts/mod/Makefile b/scripts/mod/Makefile index 42c5d50f2bcc..a5b4af47987a 100644 --- a/scripts/mod/Makefile +++ b/scripts/mod/Makefile @@ -4,6 +4,8 @@ OBJECT_FILES_NON_STANDARD := y hostprogs-y := modpost mk_elfconfig always := $(hostprogs-y) empty.o +CFLAGS_REMOVE_empty.o := $(ASM_MACRO_FLAGS) + modpost-objs := modpost.o file2alias.o sumversion.o devicetable-offsets-file := devicetable-offsets.h -- 2.17.1