kbuild: better abstract vmlinux sequential prerequisites

When CONFIG_TRIM_UNUSED_KSYMS=y and CONFIG_BUILD_DOCSRC=y it is possible
to get the following error:

ERROR: "cn_del_callback" [Documentation/connector/cn_test.ko] undefined!
ERROR: "cn_add_callback" [Documentation/connector/cn_test.ko] undefined!
ERROR: "cn_netlink_send" [Documentation/connector/cn_test.ko] undefined!
../scripts/Makefile.modpost:91: recipe for target '__modpost' failed

It is not sufficient to do "vmlinux-dirs += Documentation" as this also
depends on the headers_check target, and all of this needs to be done
before adjust_autoksyms.sh is executed.

Let's sort this out by gathering those sequential prerequisites in a make
target of their own, separate from the vmlinux target. And by doing so,
the special autoksyms_recursive target is no longer needed.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
This commit is contained in:
Nicolas Pitre 2016-04-22 15:25:00 -04:00 committed by Michal Marek
parent ba79d401f1
commit 2441e78b19

View File

@ -926,17 +926,11 @@ export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) arch Doc
vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_INIT) $(KBUILD_VMLINUX_MAIN)
# Final link of vmlinux
cmd_link-vmlinux = $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux)
quiet_cmd_link-vmlinux = LINK $@
# Include targets which we want to
# execute if the rest of the kernel build went well.
vmlinux: scripts/link-vmlinux.sh $(vmlinux-deps) FORCE
ifdef CONFIG_TRIM_UNUSED_KSYMS
$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
"$(MAKE) KBUILD_MODULES=1 -f $(srctree)/Makefile autoksyms_recursive"
endif
# Include targets which we want to execute sequentially if the rest of the
# kernel build went well. If CONFIG_TRIM_UNUSED_KSYMS is set, this might be
# evaluated more than once.
PHONY += vmlinux_prereq
vmlinux_prereq: $(vmlinux-deps) FORCE
ifdef CONFIG_HEADERS_CHECK
$(Q)$(MAKE) -f $(srctree)/Makefile headers_check
endif
@ -946,17 +940,22 @@ endif
ifdef CONFIG_GDB_SCRIPTS
$(Q)ln -fsn `cd $(srctree) && /bin/pwd`/scripts/gdb/vmlinux-gdb.py
endif
+$(call if_changed,link-vmlinux)
autoksyms_recursive: $(vmlinux-deps)
ifdef CONFIG_TRIM_UNUSED_KSYMS
$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
"$(MAKE) KBUILD_MODULES=1 -f $(srctree)/Makefile autoksyms_recursive"
PHONY += autoksyms_recursive
"$(MAKE) KBUILD_MODULES=1 -f $(srctree)/Makefile vmlinux_prereq"
endif
# standalone target for easier testing
include/generated/autoksyms.h: FORCE
$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh true
# Final link of vmlinux
cmd_link-vmlinux = $(CONFIG_SHELL) $< $(LD) $(LDFLAGS) $(LDFLAGS_vmlinux)
quiet_cmd_link-vmlinux = LINK $@
vmlinux: scripts/link-vmlinux.sh vmlinux_prereq FORCE
+$(call if_changed,link-vmlinux)
# Build samples along the rest of the kernel
ifdef CONFIG_SAMPLES
vmlinux-dirs += samples