Some headers are shared between individual architectures or are empty.
To avoid duplication of these headers, asm-generic is introduced.
With the following patch, an architecture uses generic headers
mentioned in the file arch/$(ARCH)/include/asm/Makefile
To use a generic header is needed to add to
arch/$(ARCH)/include/asm/Makefile :
generic-y += <name-of-header-file.h>
For each mentioned header in arch/$(ARCH)/include/asm/Makefile,
the necessary wrapper in arch/$(ARCH)/include/generated/asm will be
generated.
As the base Makefile.asm-generic from Linux kernel was taken.
( 06c2afb862f9da8 "Linux 6.5-rc1" ).
Signed-off-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
---
Changes in V6:
- introduce $(asm-generic) macro in Kbuild.include.
- move "asm-generic" after the rule "__distclean".
---
Changes in V5:
- Update the commit message
- Update SPDX license in Makefile.
- Remove code related to UML
- Include $(src)/Makefile instead of $(kbuild-file)
- Update comment message in Makefile.asm-generic
- Update .gitignore
- Update path to generated headers in CFLAGS.
- Use the latest version of Linux's Makefile.asm-generic
---
Changes in V4:
- introduce asm-generic support
- update commit message
---
Changes in V3:
- Rename stubs dir to asm-generic
---
Changes in V2:
- Nothing changed.
---
.gitignore | 1 +
xen/Makefile | 9 +++++-
xen/scripts/Kbuild.include | 6 ++++
xen/scripts/Makefile.asm-generic | 53 ++++++++++++++++++++++++++++++++
4 files changed, 68 insertions(+), 1 deletion(-)
create mode 100644 xen/scripts/Makefile.asm-generic
diff --git a/.gitignore b/.gitignore
index 50273adb8d..287166f8fc 100644
--- a/.gitignore
+++ b/.gitignore
@@ -267,6 +267,7 @@ xen/arch/*/efi/efi.h
xen/arch/*/efi/pe.c
xen/arch/*/efi/runtime.c
xen/arch/*/include/asm/asm-offsets.h
+xen/arch/*/include/generated
xen/build-dir-cppcheck/
xen/common/config_data.S
xen/common/config.gz
diff --git a/xen/Makefile b/xen/Makefile
index f57e5a596c..2dc5e3526d 100644
--- a/xen/Makefile
+++ b/xen/Makefile
@@ -438,6 +438,7 @@ ifdef building_out_of_srctree
endif
CFLAGS += -I$(srctree)/include
CFLAGS += -I$(srctree)/arch/$(SRCARCH)/include
+CFLAGS += -I$(objtree)/arch/$(SRCARCH)/include/generated
# Note that link order matters!
ALL_OBJS-y := common/built_in.o
@@ -580,16 +581,22 @@ _clean:
rm -f $(TARGET).efi $(TARGET).efi.map $(TARGET).efi.elf $(TARGET).efi.stripped
rm -f asm-offsets.s arch/*/include/asm/asm-offsets.h
rm -f .banner .allconfig.tmp include/xen/compile.h
+ rm -rf $(objtree)/arch/*/include/generated
.PHONY: _distclean
_distclean: clean
rm -f tags TAGS cscope.files cscope.in.out cscope.out cscope.po.out GTAGS GPATH GRTAGS GSYMS .config source
+# Support for using generic headers in asm-generic
+PHONY += asm-generic
+asm-generic:
+ $(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm
+
$(TARGET).gz: $(TARGET)
gzip -n -f -9 < $< > $@.new
mv $@.new $@
-$(TARGET): outputmakefile FORCE
+$(TARGET): outputmakefile asm-generic FORCE
$(Q)$(MAKE) $(build)=tools
$(Q)$(MAKE) $(build)=. include/xen/compile.h
$(Q)$(MAKE) $(build)=include all
diff --git a/xen/scripts/Kbuild.include b/xen/scripts/Kbuild.include
index 785a32c32e..c2bd8498e1 100644
--- a/xen/scripts/Kbuild.include
+++ b/xen/scripts/Kbuild.include
@@ -91,6 +91,12 @@ cc-ifversion = $(shell [ $(CONFIG_GCC_VERSION)0 $(1) $(2)000 ] && echo $(3) || e
clang-ifversion = $(shell [ $(CONFIG_CLANG_VERSION)0 $(1) $(2)000 ] && echo $(3) || echo $(4))
+###
+# Shorthand for $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic obj
+# Usage:
+# $(Q)$(MAKE) $(asm-generic)=dir
+asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
+
###
# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.build obj=
# Usage:
diff --git a/xen/scripts/Makefile.asm-generic b/xen/scripts/Makefile.asm-generic
new file mode 100644
index 0000000000..92a3a741c5
--- /dev/null
+++ b/xen/scripts/Makefile.asm-generic
@@ -0,0 +1,53 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# include/asm-generic contains a lot of files that are used
+# verbatim by several architectures.
+#
+# This Makefile reads the file arch/$(SRCARCH)/include/asm/Makefile
+# and for each file listed in this file with generic-y creates
+# a small wrapper file in arch/$(SRCARCH)/include/generated/asm.
+
+PHONY := all
+all:
+
+src := $(subst /generated,,$(obj))
+
+include $(srctree)/scripts/Kbuild.include
+-include $(src)/Makefile
+
+redundant := $(filter $(mandatory-y) $(generated-y), $(generic-y))
+redundant += $(foreach f, $(generic-y), $(if $(wildcard $(srctree)/$(src)/$(f)),$(f)))
+redundant := $(sort $(redundant))
+$(if $(redundant),\
+ $(warning redundant generic-y found in $(src)/Kbuild: $(redundant)))
+
+# If arch does not implement mandatory headers, fallback to asm-generic ones.
+mandatory-y := $(filter-out $(generated-y), $(mandatory-y))
+generic-y += $(foreach f, $(mandatory-y), $(if $(wildcard $(srctree)/$(src)/$(f)),,$(f)))
+
+generic-y := $(addprefix $(obj)/, $(generic-y))
+generated-y := $(addprefix $(obj)/, $(generated-y))
+
+# Remove stale wrappers when the corresponding files are removed from generic-y
+old-headers := $(wildcard $(obj)/*.h)
+unwanted := $(filter-out $(generic-y) $(generated-y),$(old-headers))
+
+quiet_cmd_wrap = WRAP $@
+ cmd_wrap = echo "\#include <asm-generic/$*.h>" > $@
+
+quiet_cmd_remove = REMOVE $(unwanted)
+ cmd_remove = rm -f $(unwanted)
+
+all: $(generic-y)
+ $(if $(unwanted),$(call cmd,remove))
+ @:
+
+$(obj)/%.h:
+ $(call cmd,wrap)
+
+# Create output directory. Skip it if at least one old header exists
+# since we know the output directory already exists.
+ifeq ($(old-headers),)
+$(shell mkdir -p $(obj))
+endif
+
+.PHONY: $(PHONY)
--
2.41.0On 07.09.2023 11:32, Oleksii Kurochko wrote: > --- /dev/null > +++ b/xen/scripts/Makefile.asm-generic > @@ -0,0 +1,53 @@ > +# SPDX-License-Identifier: GPL-2.0-only > +# include/asm-generic contains a lot of files that are used > +# verbatim by several architectures. > +# > +# This Makefile reads the file arch/$(SRCARCH)/include/asm/Makefile > +# and for each file listed in this file with generic-y creates > +# a small wrapper file in arch/$(SRCARCH)/include/generated/asm. > + > +PHONY := all > +all: > + > +src := $(subst /generated,,$(obj)) > + > +include $(srctree)/scripts/Kbuild.include > +-include $(src)/Makefile With the definition of src above, is this correct for out-of-tree builds? You want to reference the Makefile in the source tree, ... > +redundant := $(filter $(mandatory-y) $(generated-y), $(generic-y)) > +redundant += $(foreach f, $(generic-y), $(if $(wildcard $(srctree)/$(src)/$(f)),$(f))) ... much like $(srctree) is used here (and similarly again further down). Jan
On Thu, 2023-09-07 at 12:48 +0200, Jan Beulich wrote: > On 07.09.2023 11:32, Oleksii Kurochko wrote: > > --- /dev/null > > +++ b/xen/scripts/Makefile.asm-generic > > @@ -0,0 +1,53 @@ > > +# SPDX-License-Identifier: GPL-2.0-only > > +# include/asm-generic contains a lot of files that are used > > +# verbatim by several architectures. > > +# > > +# This Makefile reads the file > > arch/$(SRCARCH)/include/asm/Makefile > > +# and for each file listed in this file with generic-y creates > > +# a small wrapper file in arch/$(SRCARCH)/include/generated/asm. > > + > > +PHONY := all > > +all: > > + > > +src := $(subst /generated,,$(obj)) > > + > > +include $(srctree)/scripts/Kbuild.include > > +-include $(src)/Makefile > > With the definition of src above, is this correct for out-of-tree > builds? Logically you are right and I think it would be better to use $(srctree)/$src but it works for out-of-tree builds too. $ CONTAINER_NO_PULL=1 CONTAINER=riscv64 ./automation/scripts/containerize make O=xen-build V=2 XEN_TARGET_ARCH=riscv64 -C xen build $ ls -la xen/xen-build/arch/riscv/include/generated/asm/vm_event.h -rw-r--r--. 1 ok ok 34 вер 7 16:27 xen/xen- build/arch/riscv/include/generated/asm/vm_event.h > You want to reference the Makefile in the source tree, ... > > > +redundant := $(filter $(mandatory-y) $(generated-y), $(generic-y)) > > +redundant += $(foreach f, $(generic-y), $(if $(wildcard > > $(srctree)/$(src)/$(f)),$(f))) > > ... much like $(srctree) is used here (and similarly again further > down). > ~ Oleksii
On 07.09.2023 15:45, Oleksii wrote: > On Thu, 2023-09-07 at 12:48 +0200, Jan Beulich wrote: >> On 07.09.2023 11:32, Oleksii Kurochko wrote: >>> --- /dev/null >>> +++ b/xen/scripts/Makefile.asm-generic >>> @@ -0,0 +1,53 @@ >>> +# SPDX-License-Identifier: GPL-2.0-only >>> +# include/asm-generic contains a lot of files that are used >>> +# verbatim by several architectures. >>> +# >>> +# This Makefile reads the file >>> arch/$(SRCARCH)/include/asm/Makefile >>> +# and for each file listed in this file with generic-y creates >>> +# a small wrapper file in arch/$(SRCARCH)/include/generated/asm. >>> + >>> +PHONY := all >>> +all: >>> + >>> +src := $(subst /generated,,$(obj)) >>> + >>> +include $(srctree)/scripts/Kbuild.include >>> +-include $(src)/Makefile >> >> With the definition of src above, is this correct for out-of-tree >> builds? > Logically you are right and I think it would be better to use > $(srctree)/$src but it works for out-of-tree builds too. > > $ CONTAINER_NO_PULL=1 CONTAINER=riscv64 > ./automation/scripts/containerize make O=xen-build V=2 > XEN_TARGET_ARCH=riscv64 -C xen build > > $ ls -la xen/xen-build/arch/riscv/include/generated/asm/vm_event.h > -rw-r--r--. 1 ok ok 34 вер 7 16:27 xen/xen- > build/arch/riscv/include/generated/asm/vm_event.h Oh, right, aiui because of VPATH being set to $(srctree), and therefore in the absence of a Makefile in $(objtree)/$(src)/ it'll go look for one in $(srctree)/$(src)/. Never mind then: Acked-by: Jan Beulich <jbeulich@suse.com> Jan
On Thu, 2023-09-07 at 15:56 +0200, Jan Beulich wrote: > On 07.09.2023 15:45, Oleksii wrote: > > On Thu, 2023-09-07 at 12:48 +0200, Jan Beulich wrote: > > > On 07.09.2023 11:32, Oleksii Kurochko wrote: > > > > --- /dev/null > > > > +++ b/xen/scripts/Makefile.asm-generic > > > > @@ -0,0 +1,53 @@ > > > > +# SPDX-License-Identifier: GPL-2.0-only > > > > +# include/asm-generic contains a lot of files that are used > > > > +# verbatim by several architectures. > > > > +# > > > > +# This Makefile reads the file > > > > arch/$(SRCARCH)/include/asm/Makefile > > > > +# and for each file listed in this file with generic-y creates > > > > +# a small wrapper file in > > > > arch/$(SRCARCH)/include/generated/asm. > > > > + > > > > +PHONY := all > > > > +all: > > > > + > > > > +src := $(subst /generated,,$(obj)) > > > > + > > > > +include $(srctree)/scripts/Kbuild.include > > > > +-include $(src)/Makefile > > > > > > With the definition of src above, is this correct for out-of-tree > > > builds? > > Logically you are right and I think it would be better to use > > $(srctree)/$src but it works for out-of-tree builds too. > > > > $ CONTAINER_NO_PULL=1 CONTAINER=riscv64 > > ./automation/scripts/containerize make O=xen-build V=2 > > XEN_TARGET_ARCH=riscv64 -C xen build > > > > $ ls -la xen/xen-build/arch/riscv/include/generated/asm/vm_event.h > > -rw-r--r--. 1 ok ok 34 вер 7 16:27 xen/xen- > > build/arch/riscv/include/generated/asm/vm_event.h > > Oh, right, aiui because of VPATH being set to $(srctree), and > therefore > in the absence of a Makefile in $(objtree)/$(src)/ it'll go look for > one in $(srctree)/$(src)/. Never mind then: > Acked-by: Jan Beulich <jbeulich@suse.com> > Thanks for explanation. ~ Oleksii
On Thu, Sep 07, 2023 at 12:32:56PM +0300, Oleksii Kurochko wrote: > diff --git a/xen/scripts/Makefile.asm-generic b/xen/scripts/Makefile.asm-generic > new file mode 100644 > index 0000000000..92a3a741c5 > --- /dev/null > +++ b/xen/scripts/Makefile.asm-generic > @@ -0,0 +1,53 @@ > +# SPDX-License-Identifier: GPL-2.0-only > +# include/asm-generic contains a lot of files that are used > +# verbatim by several architectures. > +# > +# This Makefile reads the file arch/$(SRCARCH)/include/asm/Makefile > +# and for each file listed in this file with generic-y creates > +# a small wrapper file in arch/$(SRCARCH)/include/generated/asm. > + > +PHONY := all > +all: > + > +src := $(subst /generated,,$(obj)) > + > +include $(srctree)/scripts/Kbuild.include > +-include $(src)/Makefile > + > +redundant := $(filter $(mandatory-y) $(generated-y), $(generic-y)) > +redundant += $(foreach f, $(generic-y), $(if $(wildcard $(srctree)/$(src)/$(f)),$(f))) > +redundant := $(sort $(redundant)) > +$(if $(redundant),\ > + $(warning redundant generic-y found in $(src)/Kbuild: $(redundant))) This warning would need to say "$(src)/Makefile" now instead of Kbuild. Beside this, patch looks fine to me: Reviewed-by: Anthony PERARD <anthony.perard@citrix.com> Thanks, -- Anthony PERARD
On Thu, 2023-09-07 at 11:08 +0100, Anthony PERARD wrote: > On Thu, Sep 07, 2023 at 12:32:56PM +0300, Oleksii Kurochko wrote: > > diff --git a/xen/scripts/Makefile.asm-generic > > b/xen/scripts/Makefile.asm-generic > > new file mode 100644 > > index 0000000000..92a3a741c5 > > --- /dev/null > > +++ b/xen/scripts/Makefile.asm-generic > > @@ -0,0 +1,53 @@ > > +# SPDX-License-Identifier: GPL-2.0-only > > +# include/asm-generic contains a lot of files that are used > > +# verbatim by several architectures. > > +# > > +# This Makefile reads the file > > arch/$(SRCARCH)/include/asm/Makefile > > +# and for each file listed in this file with generic-y creates > > +# a small wrapper file in arch/$(SRCARCH)/include/generated/asm. > > + > > +PHONY := all > > +all: > > + > > +src := $(subst /generated,,$(obj)) > > + > > +include $(srctree)/scripts/Kbuild.include > > +-include $(src)/Makefile > > + > > +redundant := $(filter $(mandatory-y) $(generated-y), $(generic-y)) > > +redundant += $(foreach f, $(generic-y), $(if $(wildcard > > $(srctree)/$(src)/$(f)),$(f))) > > +redundant := $(sort $(redundant)) > > +$(if $(redundant),\ > > + $(warning redundant generic-y found in $(src)/Kbuild: > > $(redundant))) > > This warning would need to say "$(src)/Makefile" now instead of > Kbuild. Thanks. Missed that. > > Beside this, patch looks fine to me: > Reviewed-by: Anthony PERARD <anthony.perard@citrix.com> > > Thanks, > ~ Oleksii
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