| Message ID | 78dccec2-064f-d4b1-1865-eb3f1f14247a@suse.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | xen: beginnings of moving library-like code into an archive | expand |
(+ Anthony) Hi Jan, On 23/10/2020 11:17, Jan Beulich wrote: > 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. > > Signed-off-by: Jan Beulich <jbeulich@suse.com> > --- > xen/Rules.mk | 33 +++++++++++++++++++++++++++------ > xen/arch/arm/Makefile | 6 +++--- > xen/arch/x86/Makefile | 8 ++++---- > xen/lib/Makefile | 3 ++- IIRC, Anthony worked on the build systems. If I am right, it would be good to get a review from him. > 4 files changed, 36 insertions(+), 14 deletions(-) > > diff --git a/xen/Rules.mk b/xen/Rules.mk > index 333e19bec343..e59c7f213f77 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) > @@ -129,19 +144,25 @@ 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) $(extra-y) > ifeq ($(obj-y),) > $(CC) $(c_flags) -c -x c /dev/null -o $@ > else > ifeq ($(CONFIG_LTO),y) > - $(LD_LTO) -r -o $@ $(filter-out $(extra-y),$^) > + $(LD_LTO) -r -o $@ $(filter-out lib.a $(extra-y),$^) > else > - $(LD) $(XEN_LDFLAGS) -r -o $@ $(filter-out $(extra-y),$^) > + $(LD) $(XEN_LDFLAGS) -r -o $@ $(filter-out lib.a $(extra-y),$^) > 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 $* built_in.o > > %/built_in_bin.o: FORCE > diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile > index 296c5e68bbc3..612a83b315c8 100644 > --- a/xen/arch/arm/Makefile > +++ b/xen/arch/arm/Makefile > @@ -90,14 +90,14 @@ endif > > ifeq ($(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 > $(call if_changed,ld) > endif > > diff --git a/xen/arch/x86/Makefile b/xen/arch/x86/Makefile > index 9b368632fb43..8f2180485b2b 100644 > --- a/xen/arch/x86/Makefile > +++ b/xen/arch/x86/Makefile > @@ -132,8 +132,8 @@ EFI_OBJS-$(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 > $(call if_changed,ld) > endif > > diff --git a/xen/lib/Makefile b/xen/lib/Makefile > index 53b1da025e0d..b8814361d63e 100644 > --- a/xen/lib/Makefile > +++ b/xen/lib/Makefile > @@ -1,2 +1,3 @@ > -obj-y += ctype.o > obj-$(CONFIG_X86) += x86/ > + > +lib-y += ctype.o May I ask why all the code movement by ctype was done after this patch? Cheers,
Hi Jan, On 23/10/2020 11:17, Jan Beulich wrote: > 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. > > Signed-off-by: Jan Beulich <jbeulich@suse.com> > --- > xen/Rules.mk | 33 +++++++++++++++++++++++++++------ > xen/arch/arm/Makefile | 6 +++--- > xen/arch/x86/Makefile | 8 ++++---- > xen/lib/Makefile | 3 ++- > 4 files changed, 36 insertions(+), 14 deletions(-) I can't build Xen on Arm after this patch: AR lib.a aarch64-linux-gnu-ld -EL -r -o built_in.o aarch64-linux-gnu-ld: no input files /home/ANT.AMAZON.COM/jgrall/works/oss/xen/xen/Rules.mk:154: recipe for target 'built_in.o' failed Cheers,
On 18.11.2020 18:06, Julien Grall wrote: > On 23/10/2020 11:17, Jan Beulich wrote: >> 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. >> >> Signed-off-by: Jan Beulich <jbeulich@suse.com> >> --- >> xen/Rules.mk | 33 +++++++++++++++++++++++++++------ >> xen/arch/arm/Makefile | 6 +++--- >> xen/arch/x86/Makefile | 8 ++++---- >> xen/lib/Makefile | 3 ++- > > IIRC, Anthony worked on the build systems. If I am right, it would be > good to get a review from him. I'll try to remember next time round. >> --- a/xen/lib/Makefile >> +++ b/xen/lib/Makefile >> @@ -1,2 +1,3 @@ >> -obj-y += ctype.o >> obj-$(CONFIG_X86) += x86/ >> + >> +lib-y += ctype.o > > May I ask why all the code movement by ctype was done after this patch? I'm sorry, but I'm afraid I don't understand the question. Jan
On 18.11.2020 18:31, Julien Grall wrote: > On 23/10/2020 11:17, Jan Beulich wrote: >> 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. >> >> Signed-off-by: Jan Beulich <jbeulich@suse.com> >> --- >> xen/Rules.mk | 33 +++++++++++++++++++++++++++------ >> xen/arch/arm/Makefile | 6 +++--- >> xen/arch/x86/Makefile | 8 ++++---- >> xen/lib/Makefile | 3 ++- >> 4 files changed, 36 insertions(+), 14 deletions(-) > > I can't build Xen on Arm after this patch: > > AR lib.a > aarch64-linux-gnu-ld -EL -r -o built_in.o > aarch64-linux-gnu-ld: no input files > /home/ANT.AMAZON.COM/jgrall/works/oss/xen/xen/Rules.mk:154: recipe for > target 'built_in.o' failed Oh, indeed, this triggers a pre-existing bug. I didn't notice it because for Arm I build-tested only the series as a whole. Will add a fix for the issue as prereq patch. Thanks for noticing, Jan
diff --git a/xen/Rules.mk b/xen/Rules.mk index 333e19bec343..e59c7f213f77 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) @@ -129,19 +144,25 @@ 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) $(extra-y) ifeq ($(obj-y),) $(CC) $(c_flags) -c -x c /dev/null -o $@ else ifeq ($(CONFIG_LTO),y) - $(LD_LTO) -r -o $@ $(filter-out $(extra-y),$^) + $(LD_LTO) -r -o $@ $(filter-out lib.a $(extra-y),$^) else - $(LD) $(XEN_LDFLAGS) -r -o $@ $(filter-out $(extra-y),$^) + $(LD) $(XEN_LDFLAGS) -r -o $@ $(filter-out lib.a $(extra-y),$^) 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 $* built_in.o %/built_in_bin.o: FORCE diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile index 296c5e68bbc3..612a83b315c8 100644 --- a/xen/arch/arm/Makefile +++ b/xen/arch/arm/Makefile @@ -90,14 +90,14 @@ endif ifeq ($(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 $(call if_changed,ld) endif diff --git a/xen/arch/x86/Makefile b/xen/arch/x86/Makefile index 9b368632fb43..8f2180485b2b 100644 --- a/xen/arch/x86/Makefile +++ b/xen/arch/x86/Makefile @@ -132,8 +132,8 @@ EFI_OBJS-$(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 $(call if_changed,ld) endif diff --git a/xen/lib/Makefile b/xen/lib/Makefile index 53b1da025e0d..b8814361d63e 100644 --- a/xen/lib/Makefile +++ b/xen/lib/Makefile @@ -1,2 +1,3 @@ -obj-y += ctype.o obj-$(CONFIG_X86) += x86/ + +lib-y += ctype.o
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. Signed-off-by: Jan Beulich <jbeulich@suse.com> --- xen/Rules.mk | 33 +++++++++++++++++++++++++++------ xen/arch/arm/Makefile | 6 +++--- xen/arch/x86/Makefile | 8 ++++---- xen/lib/Makefile | 3 ++- 4 files changed, 36 insertions(+), 14 deletions(-)