kbuild: Build kernel module BTFs if BTF is enabled and pahole supports it

[linux-2.6-microblaze.git] / scripts / Makefile.modfinal

diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal
index 411c1e6..02b8924 100644 (file)
--- a/scripts/Makefile.modfinal
+++ b/scripts/Makefile.modfinal
@@ -6,6 +6,7 @@
 PHONY := __modfinal
 __modfinal:
 
+include include/config/auto.conf
 include $(srctree)/scripts/Kbuild.include
 
 # for c_flags
@@ -33,12 +34,26 @@ quiet_cmd_ld_ko_o = LD [M]  $@
       cmd_ld_ko_o =                                                     \
        $(LD) -r $(KBUILD_LDFLAGS)                                      \
                $(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE)              \
-               $(addprefix -T , $(KBUILD_LDS_MODULE))                  \
-               -o $@ $(filter %.o, $^);                                \
+               -T scripts/module.lds -o $@ $(filter %.o, $^);          \
        $(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
 
-$(modules): %.ko: %.o %.mod.o $(KBUILD_LDS_MODULE) FORCE
-       +$(call if_changed,ld_ko_o)
+quiet_cmd_btf_ko = BTF [M] $@
+      cmd_btf_ko = LLVM_OBJCOPY=$(OBJCOPY) $(PAHOLE) -J --btf_base vmlinux $@
+
+# Same as newer-prereqs, but allows to exclude specified extra dependencies
+newer_prereqs_except = $(filter-out $(PHONY) $(1),$?)
+
+# Same as if_changed, but allows to exclude specified extra dependencies
+if_changed_except = $(if $(call newer_prereqs_except,$(2))$(cmd-check),      \
+       $(cmd);                                                              \
+       printf '%s\n' 'cmd_$@ := $(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 vmlinux FORCE
+       +$(call if_changed_except,ld_ko_o,vmlinux)
+ifdef CONFIG_DEBUG_INFO_BTF_MODULES
+       +$(if $(newer-prereqs),$(call cmd,btf_ko))
+endif
 
 targets += $(modules) $(modules:.ko=.mod.o)