Message ID | 20220924181915.3251186-6-masahiroy@kernel.org (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | kbuild: various cleanups | expand |
On Sun, 25 Sep 2022 03:19:13 +0900 Masahiro Yamada wrote: > Currently, modpost is executed twice; first for vmlinux, second > for modules. > > This commit merges them. > > Current build flow > ================== > > 1) build obj-y and obj-m objects > 2) link vmlinux.o > 3) modpost for vmlinux > 4) link vmlinux > 5) modpost for modules > 6) link modules (*.ko) > > The build steps 1) through 6) are serialized, that is, modules are > built after vmlinux. You do not get benefits of parallel builds when > scripts/link-vmlinux.sh is being run. > > New build flow > ============== > > 1) build obj-y and obj-m objects > 2) link vmlinux.o > 3) modpost for vmlinux and modules > 4a) link vmlinux > 4b) link modules (*.ko) > > In the new build flow, modpost is invoked just once. > > vmlinux and modules are built in parallel. One exception is > CONFIG_DEBUG_INFO_BTF_MODULES=y, where modules depend on vmlinux. > > Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> > --- > > (no changes since v1) > > Makefile | 30 ++++++++++--- > scripts/Makefile.modfinal | 2 +- > scripts/Makefile.modpost | 93 ++++++++++++--------------------------- > scripts/link-vmlinux.sh | 3 -- > 4 files changed, 53 insertions(+), 75 deletions(-) > > diff --git a/Makefile b/Makefile > index b5dfb54b1993..cf9d7b1d8c14 100644 > --- a/Makefile > +++ b/Makefile > @@ -1152,7 +1152,7 @@ cmd_link-vmlinux = \ > $(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)"; \ > $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true) > > -vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) FORCE > +vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) modpost FORCE > +$(call if_changed_dep,link-vmlinux) > > targets := vmlinux > @@ -1428,7 +1428,13 @@ endif > # Build modules > # > > -modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_prepare > +# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFOBTF_MODULES > +# is an exception. > +ifdef CONFIG_DEBUG_INFO_BTF_MODULES > +modules: vmlinux > +endif > + > +modules: modules_prepare > > # Target to prepare building external modules > modules_prepare: prepare > @@ -1741,8 +1747,12 @@ ifdef CONFIG_MODULES > $(MODORDER): $(build-dir) > @: > > -modules: modules_check > - $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost > +# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules. > +# This is solely useful to speed up test compiles. > +modules: modpost > +ifneq ($(KBUILD_MODPOST_NOFINAL),1) > + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal > +endif > > PHONY += modules_check > modules_check: $(MODORDER) > @@ -1773,6 +1783,11 @@ KBUILD_MODULES := > > endif # CONFIG_MODULES > > +PHONY += modpost > +modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \ > + $(if $(KBUILD_MODULES), modules_check) > + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost > + > # Single targets > # --------------------------------------------------------------------------- > # To build individual files in subdirectories, you can do like this: > @@ -1792,16 +1807,19 @@ single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS))) > single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \ > $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko))) > > -$(single-ko): single_modpost > +$(single-ko): single_modules > @: > $(single-no-ko): $(build-dir) > @: > > # Remove MODORDER when done because it is not the real one. > PHONY += single_modpost PHONY += single_modules Reviewed-by: Nicolas Schier <nicolas@fjasle.eu> > -single_modpost: $(single-no-ko) modules_prepare > +single_modules: $(single-no-ko) modules_prepare > $(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER) > $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost > +ifneq ($(KBUILD_MODPOST_NOFINAL),1) > + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal > +endif > $(Q)rm -f $(MODORDER) > > single-goals := $(addprefix $(build-dir)/, $(single-no-ko)) > diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal > index 35100e981f4a..a3cf9e3647c9 100644 > --- a/scripts/Makefile.modfinal > +++ b/scripts/Makefile.modfinal > @@ -55,7 +55,7 @@ if_changed_except = $(if $(call newer_prereqs_except,$(2))$(cmd-check), \ > printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:) > > # Re-generate module BTFs if either module's .ko or vmlinux changed > -$(modules): %.ko: %.o %.mod.o scripts/module.lds $(if $(KBUILD_BUILTIN),vmlinux) FORCE > +$(modules): %.ko: %.o %.mod.o scripts/module.lds $(and $(CONFIG_DEBUG_INFO_BTF_MODULES),$(KBUILD_BUILTIN),vmlinux) FORCE > +$(call if_changed_except,ld_ko_o,vmlinux) > ifdef CONFIG_DEBUG_INFO_BTF_MODULES > +$(if $(newer-prereqs),$(call cmd,btf_ko)) > diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost > index 04ad00917b2f..2daf760eeb25 100644 > --- a/scripts/Makefile.modpost > +++ b/scripts/Makefile.modpost > @@ -32,9 +32,6 @@ > # Step 4 is solely used to allow module versioning in external modules, > # where the CRC of each module is retrieved from the Module.symvers file. > > -# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules. > -# This is solely useful to speed up test compiles > - > PHONY := __modpost > __modpost: > > @@ -45,24 +42,23 @@ MODPOST = scripts/mod/modpost \ > $(if $(CONFIG_MODVERSIONS),-m) \ > $(if $(CONFIG_MODULE_SRCVERSION_ALL),-a) \ > $(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \ > + $(if $(KBUILD_NSDEPS),-d $(MODULES_NSDEPS)) \ > + $(if $(CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS)$(KBUILD_NSDEPS),-N) \ > -o $@ > > -ifdef MODPOST_VMLINUX > - > -quiet_cmd_modpost = MODPOST $@ > - cmd_modpost = $(MODPOST) $< > - > -vmlinux.symvers: vmlinux.o > - $(call cmd,modpost) > +# 'make -i -k' ignores compile errors, and builds as many modules as possible. > +ifneq ($(findstring i,$(filter-out --%,$(MAKEFLAGS))),) > +MODPOST += -n > +endif > > -__modpost: vmlinux.symvers > +ifeq ($(KBUILD_EXTMOD),) > > # Generate the list of in-tree objects in vmlinux > # --------------------------------------------------------------------------- > > # This is used to retrieve symbol versions generated by genksyms. > ifdef CONFIG_MODVERSIONS > -vmlinux.symvers: .vmlinux.objs > +vmlinux.symvers Module.symvers: .vmlinux.objs > endif > > # Ignore libgcc.a > @@ -83,24 +79,12 @@ targets += .vmlinux.objs > .vmlinux.objs: $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS) FORCE > $(call if_changed,vmlinux_objs) > > -else > - > -ifeq ($(KBUILD_EXTMOD),) > - > -input-symdump := vmlinux.symvers > -output-symdump := modules-only.symvers > - > -quiet_cmd_cat = GEN $@ > - cmd_cat = cat $(real-prereqs) > $@ > - > -ifneq ($(wildcard vmlinux.symvers),) > - > -__modpost: Module.symvers > -Module.symvers: vmlinux.symvers modules-only.symvers FORCE > - $(call if_changed,cat) > - > -targets += Module.symvers > +vmlinux.o-if-present := $(wildcard vmlinux.o) > +output-symdump := vmlinux.symvers > > +ifdef KBUILD_MODULES > +output-symdump := $(if $(vmlinux.o-if-present), Module.symvers, modules-only.symvers) > +missing-input := $(filter-out $(vmlinux.o-if-present),vmlinux.o) > endif > > else > @@ -112,56 +96,35 @@ src := $(obj) > # Include the module's Makefile to find KBUILD_EXTRA_SYMBOLS > include $(or $(wildcard $(src)/Kbuild), $(src)/Makefile) > > -# modpost option for external modules > -MODPOST += -e > - > -input-symdump := Module.symvers $(KBUILD_EXTRA_SYMBOLS) > +module.symvers-if-present := $(wildcard Module.symvers) > output-symdump := $(KBUILD_EXTMOD)/Module.symvers > +missing-input := $(filter-out $(module.symvers-if-present), Module.symvers) > > -endif > - > -existing-input-symdump := $(wildcard $(input-symdump)) > - > -# modpost options for modules (both in-kernel and external) > -MODPOST += \ > - $(addprefix -i ,$(existing-input-symdump)) \ > - $(if $(KBUILD_NSDEPS),-d $(MODULES_NSDEPS)) \ > - $(if $(CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS)$(KBUILD_NSDEPS),-N) > - > -# 'make -i -k' ignores compile errors, and builds as many modules as possible. > -ifneq ($(findstring i,$(filter-out --%,$(MAKEFLAGS))),) > -MODPOST += -n > -endif > +MODPOST += -e $(addprefix -i ,$(module.symvers-if-present) $(KBUILD_EXTRA_SYMBOLS)) > > -# Clear VPATH to not search for *.symvers in $(srctree). Check only $(objtree). > -VPATH := > -$(input-symdump): > - @echo >&2 'WARNING: Symbol version dump "$@" is missing.' > - @echo >&2 ' Modules may not have dependencies or modversions.' > - @echo >&2 ' You may get many unresolved symbol warnings.' > +endif # ($(KBUILD_EXTMOD),) > > -# KBUILD_MODPOST_WARN can be set to avoid error out in case of undefined symbols > -ifneq ($(KBUILD_MODPOST_WARN)$(filter-out $(existing-input-symdump), $(input-symdump)),) > +ifneq ($(KBUILD_MODPOST_WARN)$(missing-input),) > MODPOST += -w > endif > > +modorder-if-needed := $(if $(KBUILD_MODULES), $(MODORDER)) > + > # Read out modules.order to pass in modpost. > # Otherwise, allmodconfig would fail with "Argument list too long". > quiet_cmd_modpost = MODPOST $@ > - cmd_modpost = sed 's/ko$$/o/' $< | $(MODPOST) -T - > - > -$(output-symdump): $(MODORDER) $(input-symdump) FORCE > - $(call if_changed,modpost) > + cmd_modpost = \ > + $(if $(missing-input), \ > + echo >&2 "WARNING: $(missing-input) is missing."; \ > + echo >&2 " Modules may not have dependencies or modversions."; \ > + echo >&2 " You may get many unresolved symbol warnings.";) \ > + sed 's/ko$$/o/' $(or $(modorder-if-needed), /dev/null) | $(MODPOST) $(vmlinux.o-if-present) -T - > > targets += $(output-symdump) > +$(output-symdump): $(modorder-if-needed) $(vmlinux.o-if-present) $(moudle.symvers-if-present) FORCE > + $(call if_changed,modpost) > > __modpost: $(output-symdump) > -ifneq ($(KBUILD_MODPOST_NOFINAL),1) > - $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal > -endif > - > -endif > - > PHONY += FORCE > FORCE: > > diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh > index 07486f90d5e2..6a197d8a88ac 100755 > --- a/scripts/link-vmlinux.sh > +++ b/scripts/link-vmlinux.sh > @@ -214,9 +214,6 @@ if [ "$1" = "clean" ]; then > exit 0 > fi > > -# modpost vmlinux.o to check for section mismatches > -${MAKE} -f "${srctree}/scripts/Makefile.modpost" MODPOST_VMLINUX=1 > - > info MODINFO modules.builtin.modinfo > ${OBJCOPY} -j .modinfo -O binary vmlinux.o modules.builtin.modinfo > info GEN modules.builtin > -- > 2.34.1
On Thu, Sep 29, 2022 at 4:59 AM Nicolas Schier <nicolas@fjasle.eu> wrote: > > On Sun, 25 Sep 2022 03:19:13 +0900 Masahiro Yamada wrote: > > Currently, modpost is executed twice; first for vmlinux, second > > for modules. > > > > This commit merges them. > > > > Current build flow > > ================== > > > > 1) build obj-y and obj-m objects > > 2) link vmlinux.o > > 3) modpost for vmlinux > > 4) link vmlinux > > 5) modpost for modules > > 6) link modules (*.ko) > > > > The build steps 1) through 6) are serialized, that is, modules are > > built after vmlinux. You do not get benefits of parallel builds when > > scripts/link-vmlinux.sh is being run. > > > > New build flow > > ============== > > > > 1) build obj-y and obj-m objects > > 2) link vmlinux.o > > 3) modpost for vmlinux and modules > > 4a) link vmlinux > > 4b) link modules (*.ko) > > > > In the new build flow, modpost is invoked just once. > > > > vmlinux and modules are built in parallel. One exception is > > CONFIG_DEBUG_INFO_BTF_MODULES=y, where modules depend on vmlinux. > > > > Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> > > --- > > > > (no changes since v1) > > > > Makefile | 30 ++++++++++--- > > scripts/Makefile.modfinal | 2 +- > > scripts/Makefile.modpost | 93 ++++++++++++--------------------------- > > scripts/link-vmlinux.sh | 3 -- > > 4 files changed, 53 insertions(+), 75 deletions(-) > > > > diff --git a/Makefile b/Makefile > > index b5dfb54b1993..cf9d7b1d8c14 100644 > > --- a/Makefile > > +++ b/Makefile > > @@ -1152,7 +1152,7 @@ cmd_link-vmlinux = \ > > $(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)"; \ > > $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true) > > > > -vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) FORCE > > +vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) modpost FORCE > > +$(call if_changed_dep,link-vmlinux) > > > > targets := vmlinux > > @@ -1428,7 +1428,13 @@ endif > > # Build modules > > # > > > > -modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_prepare > > +# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFOBTF_MODULES > > +# is an exception. > > +ifdef CONFIG_DEBUG_INFO_BTF_MODULES > > +modules: vmlinux > > +endif > > + > > +modules: modules_prepare > > > > # Target to prepare building external modules > > modules_prepare: prepare > > @@ -1741,8 +1747,12 @@ ifdef CONFIG_MODULES > > $(MODORDER): $(build-dir) > > @: > > > > -modules: modules_check > > - $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost > > +# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules. > > +# This is solely useful to speed up test compiles. > > +modules: modpost > > +ifneq ($(KBUILD_MODPOST_NOFINAL),1) > > + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal > > +endif > > > > PHONY += modules_check > > modules_check: $(MODORDER) > > @@ -1773,6 +1783,11 @@ KBUILD_MODULES := > > > > endif # CONFIG_MODULES > > > > +PHONY += modpost > > +modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \ > > + $(if $(KBUILD_MODULES), modules_check) > > + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost > > + > > # Single targets > > # --------------------------------------------------------------------------- > > # To build individual files in subdirectories, you can do like this: > > @@ -1792,16 +1807,19 @@ single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS))) > > single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \ > > $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko))) > > > > -$(single-ko): single_modpost > > +$(single-ko): single_modules > > @: > > $(single-no-ko): $(build-dir) > > @: > > > > # Remove MODORDER when done because it is not the real one. > > PHONY += single_modpost > > PHONY += single_modules Thank you for your close review! I will fix it locally. > > Reviewed-by: Nicolas Schier <nicolas@fjasle.eu> >
diff --git a/Makefile b/Makefile index b5dfb54b1993..cf9d7b1d8c14 100644 --- a/Makefile +++ b/Makefile @@ -1152,7 +1152,7 @@ cmd_link-vmlinux = \ $(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)"; \ $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true) -vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) FORCE +vmlinux: scripts/link-vmlinux.sh vmlinux.o $(KBUILD_LDS) modpost FORCE +$(call if_changed_dep,link-vmlinux) targets := vmlinux @@ -1428,7 +1428,13 @@ endif # Build modules # -modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_prepare +# *.ko are usually independent of vmlinux, but CONFIG_DEBUG_INFOBTF_MODULES +# is an exception. +ifdef CONFIG_DEBUG_INFO_BTF_MODULES +modules: vmlinux +endif + +modules: modules_prepare # Target to prepare building external modules modules_prepare: prepare @@ -1741,8 +1747,12 @@ ifdef CONFIG_MODULES $(MODORDER): $(build-dir) @: -modules: modules_check - $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost +# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules. +# This is solely useful to speed up test compiles. +modules: modpost +ifneq ($(KBUILD_MODPOST_NOFINAL),1) + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal +endif PHONY += modules_check modules_check: $(MODORDER) @@ -1773,6 +1783,11 @@ KBUILD_MODULES := endif # CONFIG_MODULES +PHONY += modpost +modpost: $(if $(single-build),, $(if $(KBUILD_BUILTIN), vmlinux.o)) \ + $(if $(KBUILD_MODULES), modules_check) + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost + # Single targets # --------------------------------------------------------------------------- # To build individual files in subdirectories, you can do like this: @@ -1792,16 +1807,19 @@ single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS))) single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \ $(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko))) -$(single-ko): single_modpost +$(single-ko): single_modules @: $(single-no-ko): $(build-dir) @: # Remove MODORDER when done because it is not the real one. PHONY += single_modpost -single_modpost: $(single-no-ko) modules_prepare +single_modules: $(single-no-ko) modules_prepare $(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER) $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost +ifneq ($(KBUILD_MODPOST_NOFINAL),1) + $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal +endif $(Q)rm -f $(MODORDER) single-goals := $(addprefix $(build-dir)/, $(single-no-ko)) diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal index 35100e981f4a..a3cf9e3647c9 100644 --- a/scripts/Makefile.modfinal +++ b/scripts/Makefile.modfinal @@ -55,7 +55,7 @@ if_changed_except = $(if $(call newer_prereqs_except,$(2))$(cmd-check), \ printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:) # Re-generate module BTFs if either module's .ko or vmlinux changed -$(modules): %.ko: %.o %.mod.o scripts/module.lds $(if $(KBUILD_BUILTIN),vmlinux) FORCE +$(modules): %.ko: %.o %.mod.o scripts/module.lds $(and $(CONFIG_DEBUG_INFO_BTF_MODULES),$(KBUILD_BUILTIN),vmlinux) FORCE +$(call if_changed_except,ld_ko_o,vmlinux) ifdef CONFIG_DEBUG_INFO_BTF_MODULES +$(if $(newer-prereqs),$(call cmd,btf_ko)) diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index 04ad00917b2f..2daf760eeb25 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -32,9 +32,6 @@ # Step 4 is solely used to allow module versioning in external modules, # where the CRC of each module is retrieved from the Module.symvers file. -# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules. -# This is solely useful to speed up test compiles - PHONY := __modpost __modpost: @@ -45,24 +42,23 @@ MODPOST = scripts/mod/modpost \ $(if $(CONFIG_MODVERSIONS),-m) \ $(if $(CONFIG_MODULE_SRCVERSION_ALL),-a) \ $(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \ + $(if $(KBUILD_NSDEPS),-d $(MODULES_NSDEPS)) \ + $(if $(CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS)$(KBUILD_NSDEPS),-N) \ -o $@ -ifdef MODPOST_VMLINUX - -quiet_cmd_modpost = MODPOST $@ - cmd_modpost = $(MODPOST) $< - -vmlinux.symvers: vmlinux.o - $(call cmd,modpost) +# 'make -i -k' ignores compile errors, and builds as many modules as possible. +ifneq ($(findstring i,$(filter-out --%,$(MAKEFLAGS))),) +MODPOST += -n +endif -__modpost: vmlinux.symvers +ifeq ($(KBUILD_EXTMOD),) # Generate the list of in-tree objects in vmlinux # --------------------------------------------------------------------------- # This is used to retrieve symbol versions generated by genksyms. ifdef CONFIG_MODVERSIONS -vmlinux.symvers: .vmlinux.objs +vmlinux.symvers Module.symvers: .vmlinux.objs endif # Ignore libgcc.a @@ -83,24 +79,12 @@ targets += .vmlinux.objs .vmlinux.objs: $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS) FORCE $(call if_changed,vmlinux_objs) -else - -ifeq ($(KBUILD_EXTMOD),) - -input-symdump := vmlinux.symvers -output-symdump := modules-only.symvers - -quiet_cmd_cat = GEN $@ - cmd_cat = cat $(real-prereqs) > $@ - -ifneq ($(wildcard vmlinux.symvers),) - -__modpost: Module.symvers -Module.symvers: vmlinux.symvers modules-only.symvers FORCE - $(call if_changed,cat) - -targets += Module.symvers +vmlinux.o-if-present := $(wildcard vmlinux.o) +output-symdump := vmlinux.symvers +ifdef KBUILD_MODULES +output-symdump := $(if $(vmlinux.o-if-present), Module.symvers, modules-only.symvers) +missing-input := $(filter-out $(vmlinux.o-if-present),vmlinux.o) endif else @@ -112,56 +96,35 @@ src := $(obj) # Include the module's Makefile to find KBUILD_EXTRA_SYMBOLS include $(or $(wildcard $(src)/Kbuild), $(src)/Makefile) -# modpost option for external modules -MODPOST += -e - -input-symdump := Module.symvers $(KBUILD_EXTRA_SYMBOLS) +module.symvers-if-present := $(wildcard Module.symvers) output-symdump := $(KBUILD_EXTMOD)/Module.symvers +missing-input := $(filter-out $(module.symvers-if-present), Module.symvers) -endif - -existing-input-symdump := $(wildcard $(input-symdump)) - -# modpost options for modules (both in-kernel and external) -MODPOST += \ - $(addprefix -i ,$(existing-input-symdump)) \ - $(if $(KBUILD_NSDEPS),-d $(MODULES_NSDEPS)) \ - $(if $(CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS)$(KBUILD_NSDEPS),-N) - -# 'make -i -k' ignores compile errors, and builds as many modules as possible. -ifneq ($(findstring i,$(filter-out --%,$(MAKEFLAGS))),) -MODPOST += -n -endif +MODPOST += -e $(addprefix -i ,$(module.symvers-if-present) $(KBUILD_EXTRA_SYMBOLS)) -# Clear VPATH to not search for *.symvers in $(srctree). Check only $(objtree). -VPATH := -$(input-symdump): - @echo >&2 'WARNING: Symbol version dump "$@" is missing.' - @echo >&2 ' Modules may not have dependencies or modversions.' - @echo >&2 ' You may get many unresolved symbol warnings.' +endif # ($(KBUILD_EXTMOD),) -# KBUILD_MODPOST_WARN can be set to avoid error out in case of undefined symbols -ifneq ($(KBUILD_MODPOST_WARN)$(filter-out $(existing-input-symdump), $(input-symdump)),) +ifneq ($(KBUILD_MODPOST_WARN)$(missing-input),) MODPOST += -w endif +modorder-if-needed := $(if $(KBUILD_MODULES), $(MODORDER)) + # Read out modules.order to pass in modpost. # Otherwise, allmodconfig would fail with "Argument list too long". quiet_cmd_modpost = MODPOST $@ - cmd_modpost = sed 's/ko$$/o/' $< | $(MODPOST) -T - - -$(output-symdump): $(MODORDER) $(input-symdump) FORCE - $(call if_changed,modpost) + cmd_modpost = \ + $(if $(missing-input), \ + echo >&2 "WARNING: $(missing-input) is missing."; \ + echo >&2 " Modules may not have dependencies or modversions."; \ + echo >&2 " You may get many unresolved symbol warnings.";) \ + sed 's/ko$$/o/' $(or $(modorder-if-needed), /dev/null) | $(MODPOST) $(vmlinux.o-if-present) -T - targets += $(output-symdump) +$(output-symdump): $(modorder-if-needed) $(vmlinux.o-if-present) $(moudle.symvers-if-present) FORCE + $(call if_changed,modpost) __modpost: $(output-symdump) -ifneq ($(KBUILD_MODPOST_NOFINAL),1) - $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modfinal -endif - -endif - PHONY += FORCE FORCE: diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 07486f90d5e2..6a197d8a88ac 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -214,9 +214,6 @@ if [ "$1" = "clean" ]; then exit 0 fi -# modpost vmlinux.o to check for section mismatches -${MAKE} -f "${srctree}/scripts/Makefile.modpost" MODPOST_VMLINUX=1 - info MODINFO modules.builtin.modinfo ${OBJCOPY} -j .modinfo -O binary vmlinux.o modules.builtin.modinfo info GEN modules.builtin
Currently, modpost is executed twice; first for vmlinux, second for modules. This commit merges them. Current build flow ================== 1) build obj-y and obj-m objects 2) link vmlinux.o 3) modpost for vmlinux 4) link vmlinux 5) modpost for modules 6) link modules (*.ko) The build steps 1) through 6) are serialized, that is, modules are built after vmlinux. You do not get benefits of parallel builds when scripts/link-vmlinux.sh is being run. New build flow ============== 1) build obj-y and obj-m objects 2) link vmlinux.o 3) modpost for vmlinux and modules 4a) link vmlinux 4b) link modules (*.ko) In the new build flow, modpost is invoked just once. vmlinux and modules are built in parallel. One exception is CONFIG_DEBUG_INFO_BTF_MODULES=y, where modules depend on vmlinux. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> --- (no changes since v1) Makefile | 30 ++++++++++--- scripts/Makefile.modfinal | 2 +- scripts/Makefile.modpost | 93 ++++++++++++--------------------------- scripts/link-vmlinux.sh | 3 -- 4 files changed, 53 insertions(+), 75 deletions(-)