tools - Add generic subdirs rules

diff -r 76c9cf11ce23 -r f08e76266aa7 tools/Makefile
@@ -37,34 +37,16 @@ endif
 endif
 
 .PHONY: all
-all:
-	@set -e; for subdir in $(SUBDIRS-y); do \
-		$(MAKE) subdir-$@-$$subdir; \
-	done
+all: subdirs-all
 
 .PHONY: install
-install:
-	@set -e; for subdir in $(SUBDIRS-y); do \
-		$(MAKE) subdir-$@-$$subdir; \
-	done
+install: subdirs-install
 	$(INSTALL_DIR) $(DESTDIR)/var/xen/dump
 	$(INSTALL_DIR) $(DESTDIR)/var/log/xen
 	$(INSTALL_DIR) $(DESTDIR)/var/lib/xen
 
 .PHONY: clean distclean
-clean distclean:
-	@set -e; for subdir in $(SUBDIRS-y); do \
-		$(MAKE) subdir-clean-$$subdir; \
-	done
-
-subdir-all-%:
-	$(MAKE) -C $* all
-
-subdir-clean-%:
-	$(MAKE) -C $* clean
-
-subdir-install-%:
-	$(MAKE) -C $* install
+clean distclean: subdirs-clean
 
 ifneq ($(XEN_COMPILE_ARCH),$(XEN_TARGET_ARCH))
 IOEMU_CONFIGURE_CROSS ?= --cross-prefix=$(CROSS_COMPILE) \

diff -r 76c9cf11ce23 -r f08e76266aa7 tools/Rules.mk
@@ -49,3 +49,13 @@ check-$(CONFIG_X86) = $(call cc-ver-chec
 %.o: %.cc
 	$(CC) $(CPPFLAGS) $(CXXFLAGS) -c -o $@ $<
 
+.PHONY: subdirs-all subdirs-clean subdirs-install
+.NOTPARALLEL: subdirs-all subdirs-clean subdirs-install
+subdirs-all subdirs-clean subdirs-install:
+	@set -e; for subdir in $(SUBDIRS) $(SUBDIRS-y); do \
+		$(MAKE) subdir-$(patsubst subdirs-%,%,$@)-$$subdir; \
+	done
+
+subdir-all-% subdir-clean-% subdir-install-%:
+	$(MAKE) -C $* $(patsubst subdir-%-$*,%,$@)
+