@@ -1085,7 +1085,7 @@ scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
# 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:
@@ -1109,7 +1109,9 @@ prepare1: prepare2 $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
include/config/auto.conf
$(cmd_crmodverdir)
-archprepare: archheaders archscripts prepare1 scripts_basic
+macroprepare: prepare1 archmacros
+
+archprepare: archheaders archscripts macroprepare scripts_basic
prepare0: archprepare gcc-plugins
$(Q)$(MAKE) $(build)=.
@@ -1214,6 +1216,9 @@ 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
@@ -235,8 +235,8 @@ ifdef CONFIG_X86_64
LDFLAGS += $(call ld-option, -z max-page-size=0x200000)
endif
-# Speed up the build
-KBUILD_CFLAGS += -pipe
+# We cannot use -pipe flag since we give an additional .s file to the compiler
+#KBUILD_CFLAGS += -pipe
# Workaround for a gcc prelease that unfortunately was shipped in a suse release
KBUILD_CFLAGS += -Wno-sign-compare
#
@@ -258,11 +258,18 @@ archscripts: scripts_basic
archheaders:
$(Q)$(MAKE) $(build)=arch/x86/entry/syscalls all
+archmacros:
+ $(Q)$(MAKE) $(build)=arch/x86/kernel macros
+
archprepare:
ifeq ($(CONFIG_KEXEC_FILE),y)
$(Q)$(MAKE) $(build)=arch/x86/purgatory arch/x86/purgatory/kexec-purgatory.c
endif
+ASM_MACRO_FLAGS = -Wa,arch/x86/kernel/macros.s
+export ASM_MACRO_FLAGS
+KBUILD_CFLAGS += $(ASM_MACRO_FLAGS)
+
###
# Kernel objects
@@ -9,6 +9,12 @@ extra-y += ebda.o
extra-y += platform-quirks.o
extra-y += vmlinux.lds
+$(obj)/macros.s: $(obj)/macros.S FORCE
+ $(call if_changed_dep,cpp_s_S)
+
+macros: $(obj)/macros.s
+ @:
+
CPPFLAGS_vmlinux.lds += -U$(UTS_MACHINE)
ifdef CONFIG_FUNCTION_TRACER
new file mode 100644
@@ -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.
+ */
@@ -189,7 +189,9 @@ __cc-option = $(call try-run-cached,\
# 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)
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: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Michal Marek <michal.lkml@markovi.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: linux-kbuild@vger.kernel.org Signed-off-by: Nadav Amit <namit@vmware.com> --- Makefile | 9 +++++++-- arch/x86/Makefile | 11 +++++++++-- arch/x86/kernel/Makefile | 6 ++++++ arch/x86/kernel/macros.S | 7 +++++++ scripts/Kbuild.include | 4 +++- 5 files changed, 32 insertions(+), 5 deletions(-) create mode 100644 arch/x86/kernel/macros.S