diff --git a/devtools/test-build.sh b/devtools/test-build.sh
index 680d79bd8f..0f131fcc67 100755
--- a/devtools/test-build.sh
+++ b/devtools/test-build.sh
@@ -146,7 +146,7 @@ config () # <directory> <target> <options>
 	fi
 	if [ ! -e $1/.config ] || $reconfig ; then
 		echo "================== Configure $1"
-		make T=$2 O=$1 config
+		make -j$J T=$2 O=$1 config
 
 		echo 'Customize configuration'
 		# Built-in options (lowercase)
diff --git a/mk/internal/rte.depdirs-post.mk b/mk/internal/rte.depdirs-post.mk
index 102a369df7..eb73ad3362 100644
--- a/mk/internal/rte.depdirs-post.mk
+++ b/mk/internal/rte.depdirs-post.mk
@@ -29,11 +29,12 @@
 #   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 #   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-.PHONY: depdirs
-depdirs:
-	@for d in $(DEPDIRS-y); do \
-		$(RTE_SDK)/buildtools/depdirs-rule.sh $(S) $$d ; \
-	done
+.PHONY: depdirs $(DEPDIRS-y)
+depdirs: $(DEPDIRS-y)
+	@echo ""
+
+$(DEPDIRS-y):
+	@$(RTE_SDK)/buildtools/depdirs-rule.sh $(S) $@
 
 .PHONY: depgraph
 depgraph:
diff --git a/mk/rte.sdkdepdirs.mk b/mk/rte.sdkdepdirs.mk
index bebaf2a297..38fd863681 100644
--- a/mk/rte.sdkdepdirs.mk
+++ b/mk/rte.sdkdepdirs.mk
@@ -36,19 +36,18 @@ ifeq (,$(wildcard $(RTE_OUTPUT)/Makefile))
   $(error "need a make config first")
 endif
 
-# use a "for" in a shell to process dependencies: we don't want this
-# task to be run in parallel.
+DEPDIR_FILES = $(addsuffix /.depdirs, $(addprefix $(BUILDDIR)/,$(ROOTDIRS-y)))
+
 .PHONY: depdirs
 depdirs: $(RTE_OUTPUT)/.depdirs
-$(RTE_OUTPUT)/.depdirs: $(RTE_OUTPUT)/.config
-	@rm -f $(RTE_OUTPUT)/.depdirs ; \
-	for d in $(ROOTDIRS-y); do \
-		if [ -f $(RTE_SRCDIR)/$$d/Makefile ]; then \
-			[ -d $(BUILDDIR)/$$d ] || mkdir -p $(BUILDDIR)/$$d ; \
-			$(MAKE) S=$$d -f $(RTE_SRCDIR)/$$d/Makefile depdirs \
-				>> $(RTE_OUTPUT)/.depdirs ; \
-		fi ; \
-	done
+$(RTE_OUTPUT)/.depdirs: $(DEPDIR_FILES)
+	@rm -f $@
+	@sort -u -o $@ $(DEPDIR_FILES)
+
+$(DEPDIR_FILES): $(RTE_OUTPUT)/.config
+	@dir=$(notdir $(@D)); \
+	[ -d $(BUILDDIR)/$$dir ] || mkdir -p $(BUILDDIR)/$$dir; \
+	$(MAKE) S=$$dir -f $(RTE_SRCDIR)/$$dir/Makefile depdirs > $@
 
 .PHONY: depgraph
 depgraph:
diff --git a/mk/rte.subdir.mk b/mk/rte.subdir.mk
index 256e64e762..5341f1feb8 100644
--- a/mk/rte.subdir.mk
+++ b/mk/rte.subdir.mk
@@ -76,7 +76,7 @@ clean: _postclean
 # include .depdirs and define rules to order priorities between build
 # of directories.
 #
-include $(RTE_OUTPUT)/.depdirs
+-include $(RTE_OUTPUT)/.depdirs
 
 define depdirs_rule
 $(1): $(sort $(patsubst $(S)/%,%,$(LOCAL_DEPDIRS-$(S)/$(1))))
@@ -84,16 +84,13 @@ endef
 
 $(foreach d,$(DIRS-y),$(eval $(call depdirs_rule,$(d))))
 
+DEPDIRS = $(wildcard $(addprefix $(S)/,$(DIRS-y)))
 
-# use a "for" in a shell to process dependencies: we don't want this
-# task to be run in parallel.
-.PHONY: depdirs
-depdirs:
-	@for d in $(DIRS-y); do \
-		if [ -f $(SRCDIR)/$$d/Makefile ]; then \
-			$(MAKE) S=$S/$$d -f $(SRCDIR)/$$d/Makefile depdirs ; \
-		fi ; \
-	done
+.PHONY: depdirs $(DEPDIRS)
+depdirs: $(DEPDIRS)
+
+$(DEPDIRS):
+	@$(MAKE) S=$@ -f $(RTE_SRCDIR)/$@/Makefile depdirs
 
 .PHONY: depgraph
 depgraph: