From: Julien Grall <julien@xen.org>
To: Anthony PERARD <anthony.perard@citrix.com>,
xen-devel@lists.xenproject.org
Cc: "Andrew Cooper" <andrew.cooper3@citrix.com>,
"George Dunlap" <george.dunlap@citrix.com>,
"Jan Beulich" <jbeulich@suse.com>,
"Stefano Stabellini" <sstabellini@kernel.org>,
"Wei Liu" <wl@xen.org>,
"Volodymyr Babchuk" <Volodymyr_Babchuk@epam.com>,
"Bertrand Marquis" <bertrand.marquis@arm.com>,
"Roger Pau Monné" <roger.pau@citrix.com>
Subject: Re: [XEN PATCH v9 04/30] build: set ALL_OBJS in main Makefile; move prelink.o to main Makefile
Date: Thu, 17 Feb 2022 19:30:39 +0000 [thread overview]
Message-ID: <b7f3e614-eebb-8247-c540-8e8a853c679c@xen.org> (raw)
In-Reply-To: <20220125110103.3527686-5-anthony.perard@citrix.com>
Hi Anthony,
On 25/01/2022 11:00, Anthony PERARD wrote:
> This is to avoid arch/$arch/Makefile having to recurse into parents
> directories.
>
> This avoid duplication of the logic to build prelink.o between arches.
>
> In order to do that, we cut the $(TARGET) target in the main Makefile in
> two, there is a "prepare" phase/target runned before starting to build
> "prelink.o" which will prepare "include/" among other things, then all
> the $(ALL_OBJS) will be generated in order to build "prelink.o" and
> finally $(TARGET) will be generated by calling into "arch/*/" to make
> $(TARGET).
>
> Now we don't need to prefix $(ALL_OBJS) with $(BASEDIR) as it is now
> only used from the main Makefile. Other changes is to use "$<" instead
> of spelling "prelink.o" in the target "$(TARGET)" in both
> arch/*/Makefile.
>
> Beside "prelink.o" been at a different location, no other functional
> change intended.
>
> Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Cheers,
> ---
>
> Notes:
> v9:
> - set ALL_OBJS and ALL_LIBS on make command line instead of exporting
> them.
> - arm/Rules.mk, have one rule instead of two for head.o
> - fix typo in title
>
> v8:
> - rebased
> - move Arm specific dependencies between $(ALL_OBJS) objects (head.o)
> into Arm specific "Rules.mk" instead of the common "build.mk".
>
> v7:
> - change, now things are in build.mk: no more prepare phase needed
>
> xen/Makefile | 12 +++++++++++-
> xen/Rules.mk | 13 -------------
> xen/arch/arm/Makefile | 31 ++++---------------------------
> xen/arch/arm/Rules.mk | 4 ++++
> xen/arch/arm/arch.mk | 2 ++
> xen/arch/x86/Makefile | 29 ++++++-----------------------
> xen/arch/x86/arch.mk | 2 ++
> xen/build.mk | 18 ++++++++++++++++++
> 8 files changed, 47 insertions(+), 64 deletions(-)
>
> diff --git a/xen/Makefile b/xen/Makefile
> index fb37043d08e0..d953dc50ac6a 100644
> --- a/xen/Makefile
> +++ b/xen/Makefile
> @@ -285,6 +285,16 @@ CFLAGS += -flto
> LDFLAGS-$(CONFIG_CC_IS_CLANG) += -plugin LLVMgold.so
> endif
>
> +# Note that link order matters!
> +ALL_OBJS-y := common/built_in.o
> +ALL_OBJS-y += drivers/built_in.o
> +ALL_OBJS-y += lib/built_in.o
> +ALL_OBJS-y += xsm/built_in.o
> +ALL_OBJS-y += arch/$(TARGET_ARCH)/built_in.o
> +ALL_OBJS-$(CONFIG_CRYPTO) += crypto/built_in.o
> +
> +ALL_LIBS-y := lib/lib.a
> +
> include $(BASEDIR)/arch/$(TARGET_ARCH)/arch.mk
>
> # define new variables to avoid the ones defined in Config.mk
> @@ -407,7 +417,7 @@ $(TARGET): FORCE
> $(MAKE) -f $(BASEDIR)/Rules.mk -C include
> $(MAKE) -f $(BASEDIR)/Rules.mk -C arch/$(TARGET_ARCH) include
> $(MAKE) -f $(BASEDIR)/Rules.mk arch/$(TARGET_ARCH)/include/asm/asm-offsets.h
> - $(MAKE) -f $(BASEDIR)/Rules.mk -C arch/$(TARGET_ARCH) MKRELOC=$(MKRELOC) $@
> + $(MAKE) -f $(BASEDIR)/Rules.mk MKRELOC=$(MKRELOC) "ALL_OBJS=$(ALL_OBJS-y)" "ALL_LIBS=$(ALL_LIBS-y)" $@
>
> SUBDIRS = xsm arch/$(TARGET_ARCH) common drivers lib test
> define all_sources
> diff --git a/xen/Rules.mk b/xen/Rules.mk
> index 7b8b9047cfd5..77d359bedaf8 100644
> --- a/xen/Rules.mk
> +++ b/xen/Rules.mk
> @@ -8,25 +8,12 @@
> include $(XEN_ROOT)/Config.mk
> include $(BASEDIR)/scripts/Kbuild.include
>
> -# Note that link order matters!
> -ALL_OBJS-y += $(BASEDIR)/common/built_in.o
> -ALL_OBJS-y += $(BASEDIR)/drivers/built_in.o
> -ALL_OBJS-y += $(BASEDIR)/lib/built_in.o
> -ALL_OBJS-y += $(BASEDIR)/xsm/built_in.o
> -ALL_OBJS-y += $(BASEDIR)/arch/$(TARGET_ARCH)/built_in.o
> -ALL_OBJS-$(CONFIG_CRYPTO) += $(BASEDIR)/crypto/built_in.o
> -
> -ALL_LIBS-y := $(BASEDIR)/lib/lib.a
> -
> # Initialise some variables
> lib-y :=
> targets :=
> CFLAGS-y :=
> AFLAGS-y :=
>
> -ALL_OBJS := $(ALL_OBJS-y)
> -ALL_LIBS := $(ALL_LIBS-y)
> -
> SPECIAL_DATA_SECTIONS := rodata $(foreach a,1 2 4 8 16, \
> $(foreach w,1 2 4, \
> rodata.str$(w).$(a)) \
> diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile
> index d0dee10102b6..14952275772b 100644
> --- a/xen/arch/arm/Makefile
> +++ b/xen/arch/arm/Makefile
> @@ -75,14 +75,6 @@ ifneq ($(CONFIG_DTB_FILE),"")
> obj-y += dtb.o
> endif
>
> -ALL_OBJS := $(TARGET_SUBARCH)/head.o $(ALL_OBJS)
> -
> -# head.o is built by descending into the sub-directory, depends on the part of
> -# $(ALL_OBJS) that will eventually recurse into $(TARGET_SUBARCH)/ and build
> -# head.o
> -$(TARGET_SUBARCH)/head.o: $(BASEDIR)/arch/arm/built_in.o
> -$(TARGET_SUBARCH)/head.o: ;
> -
> ifdef CONFIG_LIVEPATCH
> all_symbols = --all-symbols
> ifdef CONFIG_FAST_SYMBOL_LOOKUP
> @@ -98,33 +90,18 @@ ifeq ($(CONFIG_ARM_64),y)
> ln -sf $(@F) $@.efi
> endif
>
> -ifeq ($(CONFIG_LTO),y)
> -# Gather all LTO objects together
> -prelink_lto.o: $(ALL_OBJS) $(ALL_LIBS)
> - $(LD_LTO) -r -o $@ $(filter-out %.a,$^) --start-group $(filter %.a,$^) --end-group
> -
> -# Link it with all the binary objects
> -prelink.o: $(patsubst %/built_in.o,%/built_in_bin.o,$(ALL_OBJS)) prelink_lto.o
> - $(call if_changed,ld)
> -else
> -prelink.o: $(ALL_OBJS) $(ALL_LIBS) FORCE
> - $(call if_changed,ld)
> -endif
> -
> -targets += prelink.o
> -
> -$(TARGET)-syms: prelink.o xen.lds
> - $(LD) $(XEN_LDFLAGS) -T xen.lds -N prelink.o \
> +$(TARGET)-syms: $(BASEDIR)/prelink.o xen.lds
> + $(LD) $(XEN_LDFLAGS) -T xen.lds -N $< \
> $(BASEDIR)/common/symbols-dummy.o -o $(@D)/.$(@F).0
> $(NM) -pa --format=sysv $(@D)/.$(@F).0 \
> | $(BASEDIR)/tools/symbols $(all_symbols) --sysv --sort >$(@D)/.$(@F).0.S
> $(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).0.o
> - $(LD) $(XEN_LDFLAGS) -T xen.lds -N prelink.o \
> + $(LD) $(XEN_LDFLAGS) -T xen.lds -N $< \
> $(@D)/.$(@F).0.o -o $(@D)/.$(@F).1
> $(NM) -pa --format=sysv $(@D)/.$(@F).1 \
> | $(BASEDIR)/tools/symbols $(all_symbols) --sysv --sort >$(@D)/.$(@F).1.S
> $(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).1.o
> - $(LD) $(XEN_LDFLAGS) -T xen.lds -N prelink.o $(build_id_linker) \
> + $(LD) $(XEN_LDFLAGS) -T xen.lds -N $< $(build_id_linker) \
> $(@D)/.$(@F).1.o -o $@
> $(NM) -pa --format=sysv $(@D)/$(@F) \
> | $(BASEDIR)/tools/symbols --all-symbols --xensyms --sysv --sort \
> diff --git a/xen/arch/arm/Rules.mk b/xen/arch/arm/Rules.mk
> index e69de29bb2d1..c6463a433efd 100644
> --- a/xen/arch/arm/Rules.mk
> +++ b/xen/arch/arm/Rules.mk
> @@ -0,0 +1,4 @@
> +# head.o is built by descending into arch/arm/$(TARGET_SUBARCH), depends on the
> +# part of $(ALL_OBJS) that will eventually recurse into $(TARGET_SUBARCH)/ and
> +# build head.o
> +arch/arm/$(TARGET_SUBARCH)/head.o: arch/arm/built_in.o ;
> diff --git a/xen/arch/arm/arch.mk b/xen/arch/arm/arch.mk
> index c3ac443b3788..ba3f140e2ea7 100644
> --- a/xen/arch/arm/arch.mk
> +++ b/xen/arch/arm/arch.mk
> @@ -26,3 +26,5 @@ ifeq ($(CONFIG_ARM64_ERRATUM_843419),y)
> LDFLAGS += --fix-cortex-a53-843419
> endif
> endif
> +
> +ALL_OBJS-y := arch/arm/$(TARGET_SUBARCH)/head.o $(ALL_OBJS-y)
> diff --git a/xen/arch/x86/Makefile b/xen/arch/x86/Makefile
> index 9fc884813cb5..a830b5791e8b 100644
> --- a/xen/arch/x86/Makefile
> +++ b/xen/arch/x86/Makefile
> @@ -123,37 +123,20 @@ $(TARGET): $(TARGET)-syms $(efi-y) boot/mkelf32
>
> CFLAGS-$(XEN_BUILD_EFI) += -DXEN_BUILD_EFI
>
> -ALL_OBJS := $(BASEDIR)/arch/x86/boot/built_in.o $(BASEDIR)/arch/x86/efi/built_in.o $(ALL_OBJS)
> -
> -ifeq ($(CONFIG_LTO),y)
> -# Gather all LTO objects together
> -prelink_lto.o: $(ALL_OBJS) $(ALL_LIBS)
> - $(LD_LTO) -r -o $@ $(filter-out %.a,$^) --start-group $(filter %.a,$^) --end-group
> -
> -# Link it with all the binary objects
> -prelink.o: $(patsubst %/built_in.o,%/built_in_bin.o,$(ALL_OBJS)) prelink_lto.o FORCE
> - $(call if_changed,ld)
> -else
> -prelink.o: $(ALL_OBJS) $(ALL_LIBS) FORCE
> - $(call if_changed,ld)
> -endif
> -
> -targets += prelink.o
> -
> -$(TARGET)-syms: prelink.o xen.lds
> - $(LD) $(XEN_LDFLAGS) -T xen.lds -N prelink.o $(build_id_linker) \
> +$(TARGET)-syms: $(BASEDIR)/prelink.o xen.lds
> + $(LD) $(XEN_LDFLAGS) -T xen.lds -N $< $(build_id_linker) \
> $(BASEDIR)/common/symbols-dummy.o -o $(@D)/.$(@F).0
> $(NM) -pa --format=sysv $(@D)/.$(@F).0 \
> | $(BASEDIR)/tools/symbols $(all_symbols) --sysv --sort \
> >$(@D)/.$(@F).0.S
> $(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).0.o
> - $(LD) $(XEN_LDFLAGS) -T xen.lds -N prelink.o $(build_id_linker) \
> + $(LD) $(XEN_LDFLAGS) -T xen.lds -N $< $(build_id_linker) \
> $(@D)/.$(@F).0.o -o $(@D)/.$(@F).1
> $(NM) -pa --format=sysv $(@D)/.$(@F).1 \
> | $(BASEDIR)/tools/symbols $(all_symbols) --sysv --sort $(syms-warn-dup-y) \
> >$(@D)/.$(@F).1.S
> $(MAKE) -f $(BASEDIR)/Rules.mk $(@D)/.$(@F).1.o
> - $(LD) $(XEN_LDFLAGS) -T xen.lds -N prelink.o $(build_id_linker) \
> + $(LD) $(XEN_LDFLAGS) -T xen.lds -N $< $(build_id_linker) \
> $(@D)/.$(@F).1.o -o $@
> $(NM) -pa --format=sysv $(@D)/$(@F) \
> | $(BASEDIR)/tools/symbols --all-symbols --xensyms --sysv --sort \
> @@ -206,7 +189,7 @@ note_file_option ?= $(note_file)
>
> ifeq ($(XEN_BUILD_PE),y)
> extra-y += efi.lds
> -$(TARGET).efi: prelink.o $(note_file) efi.lds efi/relocs-dummy.o efi/mkreloc
> +$(TARGET).efi: $(BASEDIR)/prelink.o $(note_file) efi.lds efi/relocs-dummy.o efi/mkreloc
> ifeq ($(CONFIG_DEBUG_INFO),y)
> $(if $(filter --strip-debug,$(EFI_LDFLAGS)),echo,:) "Will strip debug info from $(@F)"
> endif
> @@ -235,7 +218,7 @@ $(TARGET).efi: FORCE
> echo '$(if $(filter y,$(XEN_BUILD_EFI)),xen.efi generation,EFI support) disabled'
> endif
>
> -efi/buildid.o efi/relocs-dummy.o: $(BASEDIR)/arch/x86/efi/built_in.o
> +# These should already have been rebuilt when building the prerequisite of "prelink.o"
> efi/buildid.o efi/relocs-dummy.o: ;
>
> .PHONY: include
> diff --git a/xen/arch/x86/arch.mk b/xen/arch/x86/arch.mk
> index fa7cf3844362..bfd5eaa35f25 100644
> --- a/xen/arch/x86/arch.mk
> +++ b/xen/arch/x86/arch.mk
> @@ -104,3 +104,5 @@ endif
>
> # Set up the assembler include path properly for older toolchains.
> CFLAGS += -Wa,-I$(BASEDIR)/include
> +
> +ALL_OBJS-y := arch/x86/boot/built_in.o arch/x86/efi/built_in.o $(ALL_OBJS-y)
> diff --git a/xen/build.mk b/xen/build.mk
> index 3d7a91df22d1..af1b28311393 100644
> --- a/xen/build.mk
> +++ b/xen/build.mk
> @@ -59,3 +59,21 @@ arch/$(TARGET_ARCH)/include/asm/asm-offsets.h: asm-offsets.s
> sed -rne "/^[^#].*==>/{s:.*==>(.*)<==.*:\1:; s: [\$$#]: :; p;}"; \
> echo ""; \
> echo "#endif") <$< >$@
> +
> +ifeq ($(CONFIG_LTO),y)
> +# Gather all LTO objects together
> +prelink_lto.o: $(ALL_OBJS) $(ALL_LIBS)
> + $(LD_LTO) -r -o $@ $(filter-out %.a,$^) --start-group $(filter %.a,$^) --end-group
> +
> +# Link it with all the binary objects
> +prelink.o: $(patsubst %/built_in.o,%/built_in_bin.o,$(ALL_OBJS)) prelink_lto.o FORCE
> + $(call if_changed,ld)
> +else
> +prelink.o: $(ALL_OBJS) $(ALL_LIBS) FORCE
> + $(call if_changed,ld)
> +endif
> +
> +targets += prelink.o
> +
> +$(TARGET): prelink.o FORCE
> + $(MAKE) -f $(BASEDIR)/Rules.mk -C arch/$(TARGET_ARCH) $@
--
Julien Grall
next prev parent reply other threads:[~2022-02-17 19:30 UTC|newest]
Thread overview: 71+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-01-25 11:00 [XEN PATCH v9 00/30] xen: Build system improvements, now with out-of-tree build! Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 01/30] build: set XEN_BUILD_EFI earlier Anthony PERARD
2022-01-27 15:35 ` Jan Beulich
2022-01-25 11:00 ` [XEN PATCH v9 02/30] build: avoid re-executing the main Makefile by introducing build.mk Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 03/30] build: fix exported variable name CFLAGS_stack_boundary Anthony PERARD
2022-01-27 15:36 ` Jan Beulich
2022-01-28 11:14 ` Jan Beulich
2022-01-28 15:04 ` Anthony PERARD
2022-01-31 8:57 ` Jan Beulich
2022-01-25 11:00 ` [XEN PATCH v9 04/30] build: set ALL_OBJS in main Makefile; move prelink.o to main Makefile Anthony PERARD
2022-01-27 15:50 ` Jan Beulich
2022-01-28 11:32 ` Anthony PERARD
2022-01-28 11:41 ` Jan Beulich
2022-02-17 16:29 ` Julien Grall
2022-02-17 19:29 ` Julien Grall
2022-02-17 15:58 ` Ping: " Anthony PERARD
2022-02-17 19:30 ` Julien Grall [this message]
2022-01-25 11:00 ` [XEN PATCH v9 05/30] build: prepare to always invoke $(MAKE) from xen/, use $(obj) Anthony PERARD
2022-01-25 16:06 ` Daniel P. Smith
2022-01-25 11:00 ` [XEN PATCH v9 06/30] build: rework test/livepatch/Makefile Anthony PERARD
2022-02-17 15:42 ` Ping: " Anthony PERARD
2022-03-08 14:15 ` Ross Lagerwall
2022-01-25 11:00 ` [XEN PATCH v9 07/30] build: rework cloc recipe Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 08/30] build: fix enforce unique symbols for recent clang version Anthony PERARD
2022-01-27 15:57 ` Jan Beulich
2022-01-28 12:03 ` Anthony PERARD
2022-01-28 12:43 ` Jan Beulich
2022-01-28 15:52 ` Anthony PERARD
2022-01-31 8:59 ` Jan Beulich
2022-01-25 11:00 ` [XEN PATCH v9 09/30] build: build everything from the root dir, use obj=$subdir Anthony PERARD
2022-01-25 16:07 ` Daniel P. Smith
2022-01-25 11:00 ` [XEN PATCH v9 10/30] build: introduce if_changed_deps Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 11/30] build: rename __LINKER__ to LINKER_SCRIPT Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 12/30] build: hook kconfig into xen build system Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 13/30] xen/tools/kconfig: fix build with -Wdeclaration-after-statement Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 14/30] build: remove KBUILD_ specific from Makefile.host Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 15/30] build: handle always-y and hostprogs-always-y Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 16/30] build: start building the tools with the main makefiles Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 17/30] build: add headers path to CFLAGS once for all archs Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 18/30] build: generate x86's asm-macros.h with filechk Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 19/30] build: clean-up "clean" rules of duplication Anthony PERARD
2022-01-25 16:09 ` Daniel P. Smith
2022-01-25 11:00 ` [XEN PATCH v9 20/30] build: rework "clean" to clean from the root dir Anthony PERARD
2022-01-25 16:09 ` Daniel P. Smith
2022-02-17 19:32 ` Julien Grall
2022-01-25 11:00 ` [XEN PATCH v9 21/30] build: use main rune to build host binary x86's mkelf32 and mkreloc Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 22/30] build: rework coverage and ubsan CFLAGS handling Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 23/30] build,x86: remove the need for build32.mk Anthony PERARD
2022-03-03 10:29 ` Jan Beulich
2022-03-03 15:31 ` Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 24/30] build: grab common EFI source files in arch specific dir Anthony PERARD
2022-02-08 21:08 ` Julien Grall
2022-03-03 10:37 ` Jan Beulich
2022-03-03 15:41 ` Anthony PERARD
2022-03-03 16:01 ` Jan Beulich
2022-03-03 16:50 ` Anthony PERARD
2022-03-03 16:54 ` Jan Beulich
2022-01-25 11:00 ` [XEN PATCH v9 25/30] build: replace $(BASEDIR) by $(objtree) Anthony PERARD
2022-01-25 11:00 ` [XEN PATCH v9 26/30] build: replace $(BASEDIR) and use $(srctree) Anthony PERARD
2022-01-25 16:10 ` Daniel P. Smith
2022-03-03 15:17 ` Anthony PERARD
2022-01-25 11:01 ` [XEN PATCH v9 27/30] build: rework "headers*.chk" prerequisite in include/ Anthony PERARD
2022-03-03 10:44 ` Jan Beulich
2022-01-25 11:01 ` [XEN PATCH v9 28/30] build: specify source tree in include/ for prerequisite Anthony PERARD
2022-03-03 10:53 ` Jan Beulich
2022-01-25 11:01 ` [XEN PATCH v9 29/30] build: shuffle main Makefile Anthony PERARD
2022-03-03 11:06 ` Jan Beulich
2022-01-25 11:01 ` [XEN PATCH v9 30/30] build: adding out-of-tree support to the xen build Anthony PERARD
2022-01-25 11:37 ` Anthony PERARD
2022-02-17 19:35 ` Julien Grall
2022-01-25 16:11 ` Daniel P. Smith
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