1# SPDX-License-Identifier: GPL-2.0-only 2# =========================================================================== 3# Module final link 4# =========================================================================== 5 6PHONY := __modfinal 7__modfinal: 8 9include include/config/auto.conf 10include $(srctree)/scripts/Kbuild.include 11 12# for c_flags 13include $(srctree)/scripts/Makefile.lib 14 15# find all modules listed in modules.order 16modules := $(sort $(shell cat $(MODORDER))) 17 18__modfinal: $(modules) 19 @: 20 21# modname and part-of-module are set to make c_flags define proper module flags 22modname = $(notdir $(@:.mod.o=)) 23part-of-module = y 24 25quiet_cmd_cc_o_c = CC [M] $@ 26 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< 27 28%.mod.o: %.mod.c FORCE 29 $(call if_changed_dep,cc_o_c) 30 31ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink) 32 33ifdef CONFIG_LTO_CLANG 34# With CONFIG_LTO_CLANG, reuse the object file we compiled for modpost to 35# avoid a second slow LTO link 36prelink-ext := .lto 37endif 38 39quiet_cmd_ld_ko_o = LD [M] $@ 40 cmd_ld_ko_o = \ 41 $(LD) -r $(KBUILD_LDFLAGS) \ 42 $(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE) \ 43 -T scripts/module.lds -o $@ $(filter %.o, $^); \ 44 $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true) 45 46quiet_cmd_btf_ko = BTF [M] $@ 47 cmd_btf_ko = \ 48 if [ -f vmlinux ]; then \ 49 LLVM_OBJCOPY=$(OBJCOPY) $(PAHOLE) -J --btf_base vmlinux $@; \ 50 else \ 51 printf "Skipping BTF generation for %s due to unavailability of vmlinux\n" $@ 1>&2; \ 52 fi; 53 54# Same as newer-prereqs, but allows to exclude specified extra dependencies 55newer_prereqs_except = $(filter-out $(PHONY) $(1),$?) 56 57# Same as if_changed, but allows to exclude specified extra dependencies 58if_changed_except = $(if $(call newer_prereqs_except,$(2))$(cmd-check), \ 59 $(cmd); \ 60 printf '%s\n' 'cmd_$@ := $(make-cmd)' > $(dot-target).cmd, @:) 61 62 63# Re-generate module BTFs if either module's .ko or vmlinux changed 64$(modules): %.ko: %$(prelink-ext).o %.mod.o scripts/module.lds $(if $(KBUILD_BUILTIN),vmlinux) FORCE 65 +$(call if_changed_except,ld_ko_o,vmlinux) 66ifdef CONFIG_DEBUG_INFO_BTF_MODULES 67 +$(if $(newer-prereqs),$(call cmd,btf_ko)) 68endif 69 70targets += $(modules) $(modules:.ko=.mod.o) 71 72# Add FORCE to the prequisites of a target to force it to be always rebuilt. 73# --------------------------------------------------------------------------- 74 75PHONY += FORCE 76FORCE: 77 78# Read all saved command lines and dependencies for the $(targets) we 79# may be building above, using $(if_changed{,_dep}). As an 80# optimization, we don't need to read them if the target does not 81# exist, we will rebuild anyway in that case. 82 83existing-targets := $(wildcard $(sort $(targets))) 84 85-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd) 86 87.PHONY: $(PHONY) 88