Re: [Qemu-devel] [RFC PATCH v3 3/5] Makefile: introduce common-obj-m and block-obj-m for DSO

[Fam Zheng <famz@redhat.com>]

On Tue, 09/10 08:45, Paolo Bonzini wrote:
> Il 10/09/2013 03:02, Fam Zheng ha scritto:
> > -all: $(DOCS) $(TOOLS) $(HELPERS-y) recurse-all
> > +# static linked mods are expanded to .o list
> > +dummy := $(call expand-mod-obj,common-obj-y)
> > +dummy := $(call expand-mod-obj,block-obj-y)
> > +
> > +modules-m = $(patsubst %.o,%$(DSOSUF),$(filter %.o,$(block-obj-m) $(common-obj-m))) \
> > +            $(patsubst %.mo,%$(DSOSUF),$(filter %.mo,$(block-obj-m) $(common-obj-m)))
> > +
> > +all: $(DOCS) $(TOOLS) $(HELPERS-y) recurse-all $(modules-m)
> > +
> > +# Generate rules for single file modules (%.so: %.o).
> > +$(foreach o,$(filter %.o,$(block-obj-m) $(common-obj-m)),$(eval \
> > +	$(patsubst %.o,%.so,$o): $o))
> > +
> > +# For multi file modules, dependencies should be listed explicitly in
> > +# Makefile.objs as
> > +#     foo.mo-objs := bar.o biz.o
> > +$(foreach o,$(filter %.mo,$(block-obj-m) $(common-obj-m)),$(eval \
> > +	$(patsubst %.mo,%.so,$o): $($o-objs)))
> 
> I agree that this foo.mo-objs variable is homogeneous with how you
> handle libraries and cflags.  I like it now.
> 
> However, I don't like the many places in which you have to special-case
> modules (expand-mod-obj, modules-m, etc.), and the duplication between
> Makefile and Makefile.target.
> 
> I would prefer if you try doing this patch along the lines I suggested
> in my review of v2, using .mo files as a placeholder and then doing the
> final link either into the .so or in the executable.  This should remove
> the need for at least expand-mod-obj, and probably for more of the
> duplicated constructs you have.
> 
OK. I'll try.

> In particular, I would like modules-m to be simply "$(block-obj-m)
> $(common-obj-m)".

There need to be some variable with %.o and %.mo subst to %.so, to become
dependency of target "all".

> 
> In the medium term, we need to find a way to avoid the duplication:
> 
>      block-obj-y = block/
>      block-obj-m = block/
> 
> Perhaps by introducing a "dirs" variable that automatically triggers
> recursion on all nested variables.  But this can be the topic of a
> separate patch series, if you prefer.
> 
Agree but prefer to do it in a separate series.

Thanks,

Fam

> >  vl.o: QEMU_CFLAGS+=$(GPROF_CFLAGS)
> >  
> > @@ -251,6 +270,9 @@ clean:
> >  	rm -f qemu-options.def
> >  	find . -name '*.[oda]' -type f -exec rm -f {} +
> >  	find . -name '*.l[oa]' -type f -exec rm -f {} +
> > +	find . -name '*.so' -type f -exec rm -f {} +
> > +	find . -name '*.dll' -type f -exec rm -f {} +
> > +
> >  	rm -f $(TOOLS) $(HELPERS-y) qemu-ga TAGS cscope.* *.pod *~ */*~
> >  	rm -Rf .libs
> >  	rm -f qemu-img-cmds.h
> > diff --git a/Makefile.objs b/Makefile.objs
> > index efd5b0f..abf59e6 100644
> > --- a/Makefile.objs
> > +++ b/Makefile.objs
> > @@ -19,6 +19,8 @@ block-obj-y += qemu-coroutine.o qemu-coroutine-lock.o qemu-coroutine-io.o
> >  block-obj-y += qemu-coroutine-sleep.o
> >  block-obj-y += coroutine-$(CONFIG_COROUTINE_BACKEND).o
> >  
> > +block-obj-m = block/
> > +
> >  ifeq ($(CONFIG_VIRTIO)$(CONFIG_VIRTFS)$(CONFIG_PCI),yyy)
> >  # Lots of the fsdev/9pcode is pulled in by vl.c via qemu_fsdev_add.
> >  # only pull in the actual virtio-9p device if we also enabled virtio.
> > @@ -83,6 +85,9 @@ common-obj-$(CONFIG_SMARTCARD_NSS) += $(libcacard-y)
> >  
> >  common-obj-y += qmp-marshal.o
> >  common-obj-y += qmp.o hmp.o
> > +
> > +common-obj-m = $(block-obj-m)
> > +
> >  endif
> >  
> >  ######################################################################
> > diff --git a/Makefile.target b/Makefile.target
> > index 381022d..8d70560 100644
> > --- a/Makefile.target
> > +++ b/Makefile.target
> > @@ -150,6 +150,10 @@ include $(SRC_PATH)/Makefile.objs
> >  obj-base := ..
> >  dummy := $(call unnest-vars)
> >  
> > +# static linked mods are expanded to .o list
> > +dummy := $(call expand-mod-obj,common-obj-y)
> > +dummy := $(call expand-mod-obj,block-obj-y)
> > +
> >  all-obj-y = $(obj-y)
> >  all-obj-y += $(addprefix ../, $(common-obj-y) $(block-obj-y))
> >  
> > diff --git a/configure b/configure
> > index cc3cd4d..c6d4a62 100755
> > --- a/configure
> > +++ b/configure
> > @@ -190,6 +190,8 @@ mingw32="no"
> >  gcov="no"
> >  gcov_tool="gcov"
> >  EXESUF=""
> > +DSOSUF=".so"
> > +LDFLAGS_SHARED="-shared"
> >  prefix="/usr/local"
> >  mandir="\${prefix}/share/man"
> >  datadir="\${prefix}/share"
> > @@ -485,6 +487,7 @@ OpenBSD)
> >  Darwin)
> >    bsd="yes"
> >    darwin="yes"
> > +  LDFLAGS_SHARED="-bundle"
> >    if [ "$cpu" = "x86_64" ] ; then
> >      QEMU_CFLAGS="-arch x86_64 $QEMU_CFLAGS"
> >      LDFLAGS="-arch x86_64 $LDFLAGS"
> > @@ -584,6 +587,7 @@ fi
> >  
> >  if test "$mingw32" = "yes" ; then
> >    EXESUF=".exe"
> > +  DSOSUF=".dll"
> >    QEMU_CFLAGS="-DWIN32_LEAN_AND_MEAN -DWINVER=0x501 $QEMU_CFLAGS"
> >    # enable C99/POSIX format strings (needs mingw32-runtime 3.15 or later)
> >    QEMU_CFLAGS="-D__USE_MINGW_ANSI_STDIO=1 $QEMU_CFLAGS"
> > @@ -4175,6 +4179,8 @@ echo "LIBTOOLFLAGS=$LIBTOOLFLAGS" >> $config_host_mak
> >  echo "LIBS+=$LIBS" >> $config_host_mak
> >  echo "LIBS_TOOLS+=$libs_tools" >> $config_host_mak
> >  echo "EXESUF=$EXESUF" >> $config_host_mak
> > +echo "DSOSUF=$DSOSUF" >> $config_host_mak
> > +echo "LDFLAGS_SHARED=$LDFLAGS_SHARED" >> $config_host_mak
> >  echo "LIBS_QGA+=$libs_qga" >> $config_host_mak
> >  echo "POD2MAN=$POD2MAN" >> $config_host_mak
> >  echo "TRANSLATE_OPT_CFLAGS=$TRANSLATE_OPT_CFLAGS" >> $config_host_mak
> > diff --git a/rules.mak b/rules.mak
> > index 84ed998..b88ac75 100644
> > --- a/rules.mak
> > +++ b/rules.mak
> > @@ -58,6 +58,10 @@ endif
> >  %.o: %.dtrace
> >  	$(call quiet-command,dtrace -o $@ -G -s $<, "  GEN   $(TARGET_DIR)$@")
> >  
> > +%$(DSOSUF): QEMU_CFLAGS += -fPIC
> > +%$(DSOSUF):
> > +	$(call quiet-command,$(LD) $^ -o $@ $(LDFLAGS_SHARED),"  LD[M] $(TARGET_DIR)$@")
> > +
> >  %$(EXESUF): %.o
> >  	$(call LINK,$^)
> >  
> > @@ -126,7 +130,11 @@ $(foreach v,$($1), \
> >  		$(eval $v-cflags := )) \
> >  	$(if $($v-libs), \
> >  		$(eval $2$v-libs := $($v-libs)) \
> > -		$(eval $v-libs := )))
> > +		$(eval $v-libs := )) \
> > +	$(if $($v-objs), \
> > +		$(eval $2$v-objs := $(addprefix $2,$($v-objs))) \
> > +		$(eval $v-objs := )) \
> > +)
> >  endef
> >  
> >  define unnest-dir
> > @@ -157,3 +165,9 @@ $(shell mkdir -p $(sort $(foreach var,$(nested-vars),$(dir $($(var))))))
> >  $(foreach var,$(nested-vars), $(eval \
> >    -include $(addsuffix *.d, $(sort $(dir $($(var)))))))
> >  endef
> > +
> > +define expand-mod-obj
> > +$(eval pref = $(if $(obj-base),$(obj-base)/,))
> > +$(eval t = $(foreach o,$($1),$(if $($(pref)$o-obj),$($(pref)$o-obj),$o)))
> > +$(eval $1 = $t)
> > +endef
> > diff --git a/tests/Makefile b/tests/Makefile
> > index 15ef039..0dda538 100644
> > --- a/tests/Makefile
> > +++ b/tests/Makefile
> > @@ -113,6 +113,7 @@ QEMU_CFLAGS += -I$(SRC_PATH)/tests
> >  nested-vars := block-obj-y
> >  obj-base := ..
> >  dummy := $(call unnest-vars)
> > +dummy := $(call expand-mod-obj,block-obj-y)
> >  
> >  tests/test-x86-cpuid.o: QEMU_INCLUDES += -I$(SRC_PATH)/target-i386
> >  
> > 
>