From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45653) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VHsyp-0002mR-Aw for qemu-devel@nongnu.org; Fri, 06 Sep 2013 06:09:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VHsyg-0000Xv-Ql for qemu-devel@nongnu.org; Fri, 06 Sep 2013 06:09:31 -0400 Received: from mail-ee0-x234.google.com ([2a00:1450:4013:c00::234]:54790) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VHsyg-0000Xq-FY for qemu-devel@nongnu.org; Fri, 06 Sep 2013 06:09:22 -0400 Received: by mail-ee0-f52.google.com with SMTP id c41so1472445eek.39 for ; Fri, 06 Sep 2013 03:09:21 -0700 (PDT) Sender: Paolo Bonzini Message-ID: <5229A9D2.30305@redhat.com> Date: Fri, 06 Sep 2013 12:09:22 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <1378452491-20467-1-git-send-email-famz@redhat.com> <1378452491-20467-4-git-send-email-famz@redhat.com> In-Reply-To: <1378452491-20467-4-git-send-email-famz@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC PATCH v2 3/6] Makefile: introduce common-obj-m and block-obj-m for DSO List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Fam Zheng Cc: peter.maydell@linaro.org, mjt@tls.msk.ru, qemu-devel@nongnu.org, stefanha@redhat.com, vilanova@ac.upc.edu, rth@twiddle.net Il 06/09/2013 09:28, Fam Zheng ha scritto: > Add necessary rules and flags for shared object generation. > $(common-obj-m) will include $(block-obj-m), like $(common-obj-y) does > for $(block-obj-y). The new rules introduced here are: > > 0) For all %.so compiling: > > QEMU_CFLAGS += -shared -fPIC > > 1) %.o in $(common-obj-m) is compiled to %.o, with "QEMU_CFLAGS += > -shared -fPIC". Then linked to %.so. > > 2) %.mo in $(common-obj-m) is the placeholder for %.so for pattern > matching in Makefile. It's linked to "-shared" with all its dependencies > (multiple *.o) as input. Which means the list of depended objects must > be ruled out in each sub-Makefile.objs with an variable: > > $(obj)/foo.mo-obj := $(addprefix $(obj)/,bar.o baz.o qux.o) > > Notice that $(obj)/ is required for both target and dependency in the > rule. DSO suffix (.so) is configure variable (.dll for Windows). Some kinks to iron, but this is really well-architected. You took all the best parts of mjt's patches and fixed almost all the ugly ones. Kudos! > Signed-off-by: Fam Zheng > --- > Makefile | 32 +++++++++++++++++++++++++++++--- > Makefile.objs | 14 +++++++++++++- > configure | 3 +++ > rules.mak | 10 ++++++++++ > 4 files changed, 55 insertions(+), 4 deletions(-) > > diff --git a/Makefile b/Makefile > index 806946e..cf47ea9 100644 > --- a/Makefile > +++ b/Makefile > @@ -56,7 +56,7 @@ Makefile: ; > configure: ; > > .PHONY: all clean cscope distclean dvi html info install install-doc \ > - pdf recurse-all speed test dist > + pdf recurse-all speed test dist modules > > $(call set-vpath, $(SRC_PATH)) > > @@ -121,7 +121,30 @@ ifeq ($(CONFIG_SMARTCARD_NSS),y) > include $(SRC_PATH)/libcacard/Makefile > endif > > -all: $(DOCS) $(TOOLS) $(HELPERS-y) recurse-all > +all: $(DOCS) $(TOOLS) $(HELPERS-y) recurse-all modules > + > +mod-obj-m = $(patsubst %.o,%$(DSOSUF),$(filter %.o,$(common-obj-m))) \ > + $(patsubst %.mo,%$(DSOSUF),$(filter %.mo,$(common-obj-m))) Why common-obj-m only, what about block-obj-m? Perhaps adding to mod-obj-m (better name: modules-m) can be done in unnest-vars? > +# Generate rules for single file modules (%.so: %.o). > +$(foreach o,$(filter %.o,$(common-obj-m)),$(eval \ > + $(patsubst %.o,%.so,$o): $o )) If you subst %.o to %.mo, you can use the same set of rules for both cases. > +# For multi file modules, dependencies should be listed explicitly in > +# Makefile.objs as > +# $(obj)/foo.mo-obj := $(obj)/bar.o $(obj)/biz.o Why not $(obj)/foo.mo: $(obj)/bar.o $(obj)/biz.o ? > +$(foreach o,$(filter %.mo,$(mod-obj-m)),$(eval \ > + $o: $($o-obj))) > + > +%.mo: > + $(if $(BUILD_DYNAMIC), \ > + $(call quiet-command,$(CC) $(sort $^) -shared -o $@," LD[M] $(TARGET_DIR)$@"), \ > + $(call quiet-command,$(AR) rcs $@ $(sort $^)," AR $(TARGET_DIR)$@")) I think we can always build modules dynamically. If the module/no-module configure option decides whether an object moves between *-obj-y and *-obj-m, statically-linked modules will just go on the linker command line with no need for $(AR) or --whole-archive/--no-whole-archive. I'm missing where is the .so built (or I guess it can just be hard-linked?) from the .mo file. IIRC -shared is not portable to Darwin. Darwin has separate file formats for dynamic libraries (.dylib) and loadable modules (.so), so it needs "-bundle" instad. All this screams "just use libtool"... > + > + > +modules: $(mod-obj-m) > +modules: BUILD_DYNAMIC = 1 > +modules: QEMU_CFLAGS += -shared -fPIC -shared is not needed here, only -fPIC. Again, libtool would abstract this nicely. But it's fine if you prefer to have v3 still without libtool and only working on ELF systems. In fact, you probably don't need a special modules target. You can just add $(mod-obj-m) to "all". > > config-host.h: config-host.h-timestamp > config-host.h-timestamp: config-host.mak > @@ -155,7 +178,7 @@ subdir-dtc:dtc/libfdt dtc/tests > dtc/%: > mkdir -p $@ > > -$(SUBDIR_RULES): libqemuutil.a libqemustub.a $(common-obj-y) > +$(SUBDIR_RULES): libqemuutil.a libqemustub.a $(common-obj-y) $(common-obj-m) > > ROMSUBDIR_RULES=$(patsubst %,romsubdir-%, $(ROMS)) > romsubdir-%: > @@ -235,6 +258,9 @@ clean: > rm -f qemu-options.def > find . -name '*.[oda]' -type f -exec rm -f {} + > find . -name '*.l[oa]' -type f -exec rm -f {} + > + find . -name '*'$(DSOSUF) -type f -exec rm -f {} + > + find . -name '*.mo' -type f -exec rm -f {} + > + > rm -f $(TOOLS) $(HELPERS-y) qemu-ga TAGS cscope.* *.pod *~ */*~ > rm -Rf .libs > rm -f qemu-img-cmds.h > diff --git a/Makefile.objs b/Makefile.objs > index f46a4cd..8984a20 100644 > --- a/Makefile.objs > +++ b/Makefile.objs > @@ -19,6 +19,8 @@ block-obj-y += qemu-coroutine.o qemu-coroutine-lock.o qemu-coroutine-io.o > block-obj-y += qemu-coroutine-sleep.o > block-obj-y += coroutine-$(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 > > ###################################################################### > @@ -121,5 +126,12 @@ nested-vars += \ > util-obj-y \ > qga-obj-y \ > block-obj-y \ > - common-obj-y > + block-obj-m \ > + common-obj-y \ > + common-obj-m > + > dummy := $(call unnest-vars) > + > +# static linked mods are expanded to .o list > +dummy := $(call expand-mod-obj,common-obj-y) > +dummy := $(call expand-mod-obj,block-obj-y) > diff --git a/configure b/configure > index af6b048..75abb87 100755 > --- a/configure > +++ b/configure > @@ -190,6 +190,7 @@ mingw32="no" > gcov="no" > gcov_tool="gcov" > EXESUF="" > +DSOSUF=".so" > prefix="/usr/local" > mandir="\${prefix}/share/man" > datadir="\${prefix}/share" > @@ -584,6 +585,7 @@ fi > > if test "$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 $QEMU_CFLAGS" > @@ -4175,6 +4177,7 @@ echo "LIBTOOLFLAGS=$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" >> $config_host_mak > echo "LIBS_QGA+=$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 e581d55..0a39499 100644 > --- a/rules.mak > +++ b/rules.mak > @@ -58,6 +58,10 @@ endif > %.o: %.dtrace > $(call quiet-command,dtrace -o $@ -G -s $<, " GEN $(TARGET_DIR)$@") > > +%$(DSOSUF): QEMU_CLFAGS += -shared -fPIC > +%$(DSOSUF): %.o > + $(call quiet-command,$(LD) $< -o $@ -shared," LD[M] $(TARGET_DIR)$@") > + As mentioned above, I think these four lines are not needed and you can always go through the "modules" or $(mod-obj-m) targets. In fact, CLFAGS sounds dubious. :) Paolo > %$(EXESUF): %.o > $(call LINK,$^) > > @@ -145,3 +149,9 @@ $(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 >