| Message ID | 20220406153023.500847-7-masahiroy@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | kbuild: more misc cleanups | expand |
On Wed, Apr 6, 2022 at 8:31 AM Masahiro Yamada <masahiroy@kernel.org> wrote: > > The dependency > > $(obj)/%.mod: $(obj)/%$(mod-prelink-ext).o > > ... exists because *.mod files previously contained undefined symbols, > which are computed from *.o files when CONFIG_TRIM_UNUSED_KSYMS=y. > > Now that the undefined symbols are put into separate *.usyms files, > there is no reason to make *.mod depend on *.o files. > > Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> > --- > > Makefile | 3 ++- > scripts/Makefile.build | 5 ++--- > 2 files changed, 4 insertions(+), 4 deletions(-) > > diff --git a/Makefile b/Makefile > index 82ee893909e9..e915aacd02b0 100644 > --- a/Makefile > +++ b/Makefile > @@ -1792,7 +1792,8 @@ ifdef single-build > > # .ko is special because modpost is needed > single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS))) > -single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS))) > +single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \ > + $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko))) I'm on board with this patch, and the overall goal with the series. My brain is having a hard time parsing `o mod` though. Can you walk me through that? Are those targets for .o and .mod files, respectively? > > $(single-ko): single_modpost > @: > diff --git a/scripts/Makefile.build b/scripts/Makefile.build > index f7a30f378e20..3da731cf6978 100644 > --- a/scripts/Makefile.build > +++ b/scripts/Makefile.build > @@ -85,7 +85,7 @@ ifdef need-builtin > targets-for-builtin += $(obj)/built-in.a > endif > > -targets-for-modules := $(foreach x, mod $(if $(CONFIG_TRIM_UNUSED_KSYMS), usyms), \ > +targets-for-modules := $(foreach x, o mod $(if $(CONFIG_TRIM_UNUSED_KSYMS), usyms), \ > $(patsubst %.o, %.$x, $(filter %.o, $(obj-m)))) > > ifneq ($(CONFIG_LTO_CLANG)$(CONFIG_X86_KERNEL_IBT),) > @@ -306,7 +306,7 @@ endif > cmd_mod = echo $(addprefix $(obj)/, $(call real-search, $*.o, .o, -objs -y -m)) | \ > $(AWK) -v RS='( |\n)' '!x[$$0]++' > $@ > > -$(obj)/%.mod: $(obj)/%$(mod-prelink-ext).o FORCE > +$(obj)/%.mod: FORCE > $(call if_changed,mod) > > # List module undefined symbols > @@ -469,7 +469,6 @@ $(multi-obj-m): FORCE > $(call if_changed,link_multi-m) > $(call multi_depend, $(multi-obj-m), .o, -objs -y -m) > > -targets += $(multi-obj-m) > targets := $(filter-out $(PHONY), $(targets)) > > # Add intermediate targets: > -- > 2.32.0 >
From: Nick Desaulniers > Sent: 07 April 2022 18:59 > > On Wed, Apr 6, 2022 at 8:31 AM Masahiro Yamada <masahiroy@kernel.org> wrote: > > > > The dependency > > > > $(obj)/%.mod: $(obj)/%$(mod-prelink-ext).o > > > > ... exists because *.mod files previously contained undefined symbols, > > which are computed from *.o files when CONFIG_TRIM_UNUSED_KSYMS=y. > > > > Now that the undefined symbols are put into separate *.usyms files, > > there is no reason to make *.mod depend on *.o files. > > > > Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> > > --- > > > > Makefile | 3 ++- > > scripts/Makefile.build | 5 ++--- > > 2 files changed, 4 insertions(+), 4 deletions(-) > > > > diff --git a/Makefile b/Makefile > > index 82ee893909e9..e915aacd02b0 100644 > > --- a/Makefile > > +++ b/Makefile > > @@ -1792,7 +1792,8 @@ ifdef single-build > > > > # .ko is special because modpost is needed > > single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS))) > > -single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS))) > > +single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \ > > + $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko))) > > I'm on board with this patch, and the overall goal with the series. My > brain is having a hard time parsing `o mod` though. Can you walk me > through that? Are those targets for .o and .mod files, respectively? I think I'd do: single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) single-no-ko += $(patsubst %.ko, %.o, $(single-ko)) single-no-ko += $(patsubst %.ko, %.mod, $(single-ko)) Although you can use the simpler SYSV make suffix substitution syntax: single-no-ko += $(single-ko:.ko=.o) $(single-ko:.ko=.mod) David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
On Fri, Apr 8, 2022 at 6:39 AM David Laight <David.Laight@aculab.com> wrote: > > From: Nick Desaulniers > > Sent: 07 April 2022 18:59 > > > > On Wed, Apr 6, 2022 at 8:31 AM Masahiro Yamada <masahiroy@kernel.org> wrote: > > > > > > The dependency > > > > > > $(obj)/%.mod: $(obj)/%$(mod-prelink-ext).o > > > > > > ... exists because *.mod files previously contained undefined symbols, > > > which are computed from *.o files when CONFIG_TRIM_UNUSED_KSYMS=y. > > > > > > Now that the undefined symbols are put into separate *.usyms files, > > > there is no reason to make *.mod depend on *.o files. > > > > > > Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> > > > --- > > > > > > Makefile | 3 ++- > > > scripts/Makefile.build | 5 ++--- > > > 2 files changed, 4 insertions(+), 4 deletions(-) > > > > > > diff --git a/Makefile b/Makefile > > > index 82ee893909e9..e915aacd02b0 100644 > > > --- a/Makefile > > > +++ b/Makefile > > > @@ -1792,7 +1792,8 @@ ifdef single-build > > > > > > # .ko is special because modpost is needed > > > single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS))) > > > -single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS))) > > > +single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \ > > > + $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko))) > > > > I'm on board with this patch, and the overall goal with the series. My > > brain is having a hard time parsing `o mod` though. Can you walk me > > through that? Are those targets for .o and .mod files, respectively? Yes. Kbuild can build a module individually. make foo/bar/baz.ko (but modpost check does not work well) To do this, Kbuild needs to descend to the directory and generate foo/bar/baz.o and foo/bar/baz.mod. Previously, foo/bar/baz.o was generated as a prerequisite of foo/bar/baz.mod, but now we need to request Kbuild to generate both of them. > I think I'd do: > single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) > single-no-ko += $(patsubst %.ko, %.o, $(single-ko)) > single-no-ko += $(patsubst %.ko, %.mod, $(single-ko)) > > Although you can use the simpler SYSV make suffix substitution syntax: > single-no-ko += $(single-ko:.ko=.o) $(single-ko:.ko=.mod) Right. I tend to use $(patsubst ), but in some places, shorter SYSV syntax is used. I admit inconsistency. > > David > > - > Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK > Registration No: 1397386 (Wales)
On Fri, Apr 8, 2022 at 9:37 AM Masahiro Yamada <masahiroy@kernel.org> wrote: > > On Fri, Apr 8, 2022 at 6:39 AM David Laight <David.Laight@aculab.com> wrote: > > > > From: Nick Desaulniers > > > Sent: 07 April 2022 18:59 > > > > > > On Wed, Apr 6, 2022 at 8:31 AM Masahiro Yamada <masahiroy@kernel.org> wrote: > > > > > > > > The dependency > > > > > > > > $(obj)/%.mod: $(obj)/%$(mod-prelink-ext).o > > > > > > > > ... exists because *.mod files previously contained undefined symbols, > > > > which are computed from *.o files when CONFIG_TRIM_UNUSED_KSYMS=y. > > > > > > > > Now that the undefined symbols are put into separate *.usyms files, > > > > there is no reason to make *.mod depend on *.o files. > > > > > > > > Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> > > > > --- > > > > > > > > Makefile | 3 ++- > > > > scripts/Makefile.build | 5 ++--- > > > > 2 files changed, 4 insertions(+), 4 deletions(-) > > > > > > > > diff --git a/Makefile b/Makefile > > > > index 82ee893909e9..e915aacd02b0 100644 > > > > --- a/Makefile > > > > +++ b/Makefile > > > > @@ -1792,7 +1792,8 @@ ifdef single-build > > > > > > > > # .ko is special because modpost is needed > > > > single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS))) > > > > -single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS))) > > > > +single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \ > > > > + $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko))) > > > > > > I'm on board with this patch, and the overall goal with the series. My > > > brain is having a hard time parsing `o mod` though. Can you walk me > > > through that? Are those targets for .o and .mod files, respectively? > > > Yes. > > Kbuild can build a module individually. > > make foo/bar/baz.ko > > (but modpost check does not work well) > > To do this, Kbuild needs to descend to > the directory and generate > foo/bar/baz.o and foo/bar/baz.mod. > > Previously, foo/bar/baz.o was generated as a > prerequisite of foo/bar/baz.mod, but now we > need to request Kbuild to generate both of them. > BTW, this feature is broken for CONFIG_LTO_CLANG=y because the ELF object is not foo/bar/baz.o but foo/bar/baz.prelink.o (which was renamed from foo/bar/baz.lto.o). I will not fix it, though.
diff --git a/Makefile b/Makefile index 82ee893909e9..e915aacd02b0 100644 --- a/Makefile +++ b/Makefile @@ -1792,7 +1792,8 @@ ifdef single-build # .ko is special because modpost is needed single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS))) -single-no-ko := $(sort $(patsubst %.ko,%.mod, $(MAKECMDGOALS))) +single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \ + $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko))) $(single-ko): single_modpost @: diff --git a/scripts/Makefile.build b/scripts/Makefile.build index f7a30f378e20..3da731cf6978 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -85,7 +85,7 @@ ifdef need-builtin targets-for-builtin += $(obj)/built-in.a endif -targets-for-modules := $(foreach x, mod $(if $(CONFIG_TRIM_UNUSED_KSYMS), usyms), \ +targets-for-modules := $(foreach x, o mod $(if $(CONFIG_TRIM_UNUSED_KSYMS), usyms), \ $(patsubst %.o, %.$x, $(filter %.o, $(obj-m)))) ifneq ($(CONFIG_LTO_CLANG)$(CONFIG_X86_KERNEL_IBT),) @@ -306,7 +306,7 @@ endif cmd_mod = echo $(addprefix $(obj)/, $(call real-search, $*.o, .o, -objs -y -m)) | \ $(AWK) -v RS='( |\n)' '!x[$$0]++' > $@ -$(obj)/%.mod: $(obj)/%$(mod-prelink-ext).o FORCE +$(obj)/%.mod: FORCE $(call if_changed,mod) # List module undefined symbols @@ -469,7 +469,6 @@ $(multi-obj-m): FORCE $(call if_changed,link_multi-m) $(call multi_depend, $(multi-obj-m), .o, -objs -y -m) -targets += $(multi-obj-m) targets := $(filter-out $(PHONY), $(targets)) # Add intermediate targets:
The dependency $(obj)/%.mod: $(obj)/%$(mod-prelink-ext).o ... exists because *.mod files previously contained undefined symbols, which are computed from *.o files when CONFIG_TRIM_UNUSED_KSYMS=y. Now that the undefined symbols are put into separate *.usyms files, there is no reason to make *.mod depend on *.o files. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> --- Makefile | 3 ++- scripts/Makefile.build | 5 ++--- 2 files changed, 4 insertions(+), 4 deletions(-)