From f301f9a9e84f3cfd18750065f8a3794c8182c7f0 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Fri, 18 Dec 2020 13:17:57 +0100 Subject: [PATCH] lib: collect library files in an archive In order to (subsequently) drop odd things like CONFIG_NEEDS_LIST_SORT just to avoid bloating binaries when only some arch-es and/or configurations need generic library routines, combine objects under lib/ into an archive, which the linker then can pick the necessary objects out of. Note that we can't use thin archives just yet, until we've raised the minimum required binutils version suitably. Note further that --start-group / --end-group get put in place right away to allow for symbol resolution across all archives, once we gain multuiple ones. Signed-off-by: Jan Beulich Acked-by: Wei Liu Reviewed-by: Bertrand Marquis Acked-by: Julien Grall --- xen/Rules.mk | 29 +++++++++++++++++++++++++---- xen/arch/arm/Makefile | 6 +++--- xen/arch/x86/Makefile | 8 ++++---- xen/lib/Makefile | 3 ++- 4 files changed, 34 insertions(+), 12 deletions(-) diff --git a/xen/Rules.mk b/xen/Rules.mk index d5e5eb33de..aba6ca2a90 100644 --- a/xen/Rules.mk +++ b/xen/Rules.mk @@ -41,12 +41,16 @@ ALL_OBJS-y += $(BASEDIR)/xsm/built_in.o ALL_OBJS-y += $(BASEDIR)/arch/$(TARGET_ARCH)/built_in.o ALL_OBJS-$(CONFIG_CRYPTO) += $(BASEDIR)/crypto/built_in.o +ALL_LIBS-y := $(BASEDIR)/lib/lib.a + # Initialise some variables +lib-y := targets := CFLAGS-y := AFLAGS-y := ALL_OBJS := $(ALL_OBJS-y) +ALL_LIBS := $(ALL_LIBS-y) SPECIAL_DATA_SECTIONS := rodata $(foreach a,1 2 4 8 16, \ $(foreach w,1 2 4, \ @@ -60,7 +64,14 @@ include Makefile # --------------------------------------------------------------------------- quiet_cmd_ld = LD $@ -cmd_ld = $(LD) $(XEN_LDFLAGS) -r -o $@ $(real-prereqs) +cmd_ld = $(LD) $(XEN_LDFLAGS) -r -o $@ $(filter-out %.a,$(real-prereqs)) \ + --start-group $(filter %.a,$(real-prereqs)) --end-group + +# Archive +# --------------------------------------------------------------------------- + +quiet_cmd_ar = AR $@ +cmd_ar = rm -f $@; $(AR) cPrs $@ $(real-prereqs) # Objcopy # --------------------------------------------------------------------------- @@ -86,6 +97,10 @@ obj-y := $(patsubst %/, %/built_in.o, $(obj-y)) # tell kbuild to descend subdir-obj-y := $(filter %/built_in.o, $(obj-y)) +# Libraries are always collected in one lib file. +# Filter out objects already built-in +lib-y := $(filter-out $(obj-y), $(sort $(lib-y))) + $(filter %.init.o,$(obj-y) $(obj-bin-y) $(extra-y)): CFLAGS-y += -DINIT_SECTIONS_ONLY ifeq ($(CONFIG_COVERAGE),y) @@ -129,7 +144,7 @@ include $(BASEDIR)/arch/$(TARGET_ARCH)/Rules.mk c_flags += $(CFLAGS-y) a_flags += $(CFLAGS-y) $(AFLAGS-y) -built_in.o: $(obj-y) $(extra-y) +built_in.o: $(obj-y) $(if $(strip $(lib-y)),lib.a) $(extra-y) ifeq ($(strip $(obj-y)),) $(CC) $(c_flags) -c -x c /dev/null -o $@ else @@ -140,8 +155,14 @@ else endif endif +lib.a: $(lib-y) FORCE + $(call if_changed,ar) + targets += built_in.o -targets += $(filter-out $(subdir-obj-y), $(obj-y)) $(extra-y) +ifneq ($(strip $(lib-y)),) +targets += lib.a +endif +targets += $(filter-out $(subdir-obj-y), $(obj-y) $(lib-y)) $(extra-y) targets += $(MAKECMDGOALS) built_in_bin.o: $(obj-bin-y) $(extra-y) @@ -155,7 +176,7 @@ endif PHONY += FORCE FORCE: -%/built_in.o: FORCE +%/built_in.o %/lib.a: FORCE $(MAKE) -f $(BASEDIR)/Rules.mk -C $* built_in.o %/built_in_bin.o: FORCE diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile index ad2d497c45..512ffdd781 100644 --- a/xen/arch/arm/Makefile +++ b/xen/arch/arm/Makefile @@ -90,14 +90,14 @@ endif ifeq ($(CONFIG_LTO),y) # Gather all LTO objects together -prelink_lto.o: $(ALL_OBJS) - $(LD_LTO) -r -o $@ $^ +prelink_lto.o: $(ALL_OBJS) $(ALL_LIBS) + $(LD_LTO) -r -o $@ $(filter-out %.a,$^) --start-group $(filter %.a,$^) --end-group # Link it with all the binary objects prelink.o: $(patsubst %/built_in.o,%/built_in_bin.o,$(ALL_OBJS)) prelink_lto.o $(call if_changed,ld) else -prelink.o: $(ALL_OBJS) FORCE +prelink.o: $(ALL_OBJS) $(ALL_LIBS) FORCE $(call if_changed,ld) endif diff --git a/xen/arch/x86/Makefile b/xen/arch/x86/Makefile index 9b368632fb..8f2180485b 100644 --- a/xen/arch/x86/Makefile +++ b/xen/arch/x86/Makefile @@ -132,8 +132,8 @@ EFI_OBJS-$(XEN_BUILD_EFI) := efi/relocs-dummy.o ifeq ($(CONFIG_LTO),y) # Gather all LTO objects together -prelink_lto.o: $(ALL_OBJS) - $(LD_LTO) -r -o $@ $^ +prelink_lto.o: $(ALL_OBJS) $(ALL_LIBS) + $(LD_LTO) -r -o $@ $(filter-out %.a,$^) --start-group $(filter %.a,$^) --end-group # Link it with all the binary objects prelink.o: $(patsubst %/built_in.o,%/built_in_bin.o,$(ALL_OBJS)) prelink_lto.o $(EFI_OBJS-y) FORCE @@ -142,10 +142,10 @@ prelink.o: $(patsubst %/built_in.o,%/built_in_bin.o,$(ALL_OBJS)) prelink_lto.o $ prelink-efi.o: $(patsubst %/built_in.o,%/built_in_bin.o,$(ALL_OBJS)) prelink_lto.o FORCE $(call if_changed,ld) else -prelink.o: $(ALL_OBJS) $(EFI_OBJS-y) FORCE +prelink.o: $(ALL_OBJS) $(ALL_LIBS) $(EFI_OBJS-y) FORCE $(call if_changed,ld) -prelink-efi.o: $(ALL_OBJS) FORCE +prelink-efi.o: $(ALL_OBJS) $(ALL_LIBS) FORCE $(call if_changed,ld) endif diff --git a/xen/lib/Makefile b/xen/lib/Makefile index 53b1da025e..b8814361d6 100644 --- a/xen/lib/Makefile +++ b/xen/lib/Makefile @@ -1,2 +1,3 @@ -obj-y += ctype.o obj-$(CONFIG_X86) += x86/ + +lib-y += ctype.o -- 2.30.2