android_kernel_xiaomi_sm8350/scripts/Makefile.modfinal
Sami Tolvanen d671af5fd7 ANDROID: kbuild: fix dynamic ftrace with clang LTO
With CONFIG_LTO_CLANG enabled, LLVM IR won't be compiled into object
files until modpost_link. This change postpones calls to recordmcount
until after this step.

In order to exclude ftrace_process_locs from inspection, we add a new
code section .text..ftrace, which we tell recordmcount to ignore, and
a __norecordmcount attribute for moving functions to this section.

Bug: 145210207
Change-Id: Ib77f7c431fce54243c46d584b55761ed2342965c
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
2019-11-27 12:49:10 -08:00

78 lines
2.4 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0-only
# ===========================================================================
# Module final link
# ===========================================================================
PHONY := __modfinal
__modfinal:
include $(objtree)/include/config/auto.conf
include $(srctree)/scripts/Kbuild.include
# for c_flags
include $(srctree)/scripts/Makefile.lib
# find all modules listed in modules.order
modules := $(sort $(shell cat $(MODORDER)))
__modfinal: $(modules)
@:
# modname and part-of-module are set to make c_flags define proper module flags
modname = $(notdir $(@:.mod.o=))
part-of-module = y
quiet_cmd_cc_o_c = CC [M] $@
cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
%.mod.o: %.mod.c FORCE
$(call if_changed_dep,cc_o_c)
ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
quiet_cmd_ld_ko_o = LD [M] $@
ifdef CONFIG_LTO_CLANG
cmd_ld_ko_o = \
$(LD) -r $(LDFLAGS) \
$(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE) \
$(addprefix -T , $(KBUILD_LDS_MODULE)) \
$(shell [ -s $(@:.ko=.o.symversions) ] && \
echo -T $(@:.ko=.o.symversions)) \
-o $@ --whole-archive $(filter %.o, $^); \
$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
ifdef CONFIG_FTRACE_MCOUNT_RECORD
cmd_ld_ko_o += ; $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) $@
endif
else
cmd_ld_ko_o = \
$(LD) -r $(KBUILD_LDFLAGS) \
$(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE) \
$(addprefix -T , $(KBUILD_LDS_MODULE)) \
-o $@ $(filter %.o, $^); \
$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
endif
$(modules): %.ko: %.o %.mod.o $(KBUILD_LDS_MODULE) FORCE
+$(call if_changed,ld_ko_o)
targets += $(modules) $(modules:.ko=.mod.o)
# Add FORCE to the prequisites of a target to force it to be always rebuilt.
# ---------------------------------------------------------------------------
PHONY += FORCE
FORCE:
# Read all saved command lines and dependencies for the $(targets) we
# may be building above, using $(if_changed{,_dep}). As an
# optimization, we don't need to read them if the target does not
# exist, we will rebuild anyway in that case.
existing-targets := $(wildcard $(sort $(targets)))
-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
.PHONY: $(PHONY)