On Fri, Oct 05, 2012 at 10:24:30AM +0200, Paolo Bonzini wrote: > Il 04/10/2012 19:33, Michael Roth ha scritto: > > + > > +%.qidl.c: %.c $(SRC_PATH)/qidl.h $(addprefix $(SRC_PATH)/scripts/,lexer.py > > qidl.py qidl_parser.py qapi.py qapi_visit.py) > > + $(call rm -f $(*D)/qidl-generated/$(*F).qidl.c) > > + $(if $(strip $(shell grep "QIDL_ENABLE()" $< 1>/dev/null && echo > > "true")), \ > > + $(call quiet-command, \ > > + $(CC) $(QEMU_INCLUDES) $(QEMU_CFLAGS) $(CFLAGS) -E -c -DQIDL_GEN $< > > | \ > > + $(PYTHON) $(SRC_PATH)/scripts/qidl.py \ > > + --output-filepath=$(*D)/qidl-generated/$(*F).qidl.c || [ "$$?" -eq > > 2 ], \ > > + "qidl PP $(*D)/$(*F).c"),) > > +%.o: %.c %.qidl.c > > + $(if $(strip $(shell test -f $(*D)/qidl-generated/$(*F).qidl.c && echo > > "true")), \ > > + $(call quiet-command, \ > > + $(CC) $(QEMU_INCLUDES) $(QEMU_CFLAGS) $(QEMU_DGFLAGS) $(CFLAGS) -c \ > > + -DQIDL_ENABLED -include $< -o $@ > > $(*D)/qidl-generated/$(*F).qidl.c, \ > > + "qidl CC $@"), \ > > + $(call quiet-command, \ > > + $(CC) $(QEMU_INCLUDES) $(QEMU_CFLAGS) $(QEMU_DGFLAGS) $(CFLAGS) -c \ > > + -o $@ $<," CC $@")) > > > Because the .qidl.c files are not created for files without a QIDL_ENABLE() > directive, all those files will be grepped on every invocation of the > makefile. > > It is better to define the list of QIDL_ENABLEd files in an auxiliary makefile > like this (untested):
Thanks for the suggestion / example. FYI, I tried to get this working but didn't manage to get it in for v4. Everything seems to be falling back to the non-qidl %o: target, and I haven't had time to debug it. FWIW, it doesn't seem to be a major factor performance-wise. Current build times on my laptop are (for all-target builds): QIDL v4: real 8m35.383s user 31m1.844s sys 1m33.998s upstream: real 8m28.181s user 30m44.983s sys 1m29.926s There's also a potential performance trade-off with the suggested approach in that a smaller build might be slower due to us always grepping over an exhaustive list of possibly QIDL-fied files. To be optimal we'd want to limit the search to objects the target actually pulls in. Maintainance-wise, there's also a nice benefit in the current approach in that we don't need to maintain a list of files to scan through, so anything we add to the tree will get picked up by QIDL automatically. So hopefully the current approach is a reasonable start for now. > > QIDL_FILES = > -include qemu-idl-files.mak > qemu-idl-files.mak: $(obj-y) $(common-obj-y) $(hw-obj-y) > (grep -l "QIDL_ENABLE()" $^ || :) | sed 's/^/QIDL_FILES += /' > $@ > > $(QIDL_FILES): %.qidl.c: %.c > $(call quiet-command, \ > $(CC) $(QEMU_INCLUDES) $(QEMU_CFLAGS) $(CFLAGS) -E -c -DQIDL_GEN $< > | \ > $(PYTHON) $(SRC_PATH)/scripts/qidl.py \ > --output-filepath=$(*D)/qidl-generated/tmp-$(*F).qidl.c || [ "$$?" > -eq 2 ], \ > "qidl PP $(*D)/$(*F).c"),) > mv $(*D)/qidl-generated/tmp-$(*F).qidl.c > $(*D)/qidl-generated/$(*F).qidl.c > > $(QIDL_FILES): %.o: %.c %.qidl.c > $(call quiet-command, \ > $(CC) $(QEMU_INCLUDES) $(QEMU_CFLAGS) $(QEMU_DGFLAGS) $(CFLAGS) -c \ > -DQIDL_ENABLED -include $< -o $@ > $(*D)/qidl-generated/$(*F).qidl.c, \ > "qidl CC $@"), \ > > %.o: %.c > $(call quiet-command, \ > $(CC) $(QEMU_INCLUDES) $(QEMU_CFLAGS) $(QEMU_DGFLAGS) $(CFLAGS) -c \ > -o $@ $<," CC $@")) > > Paolo >
