jack2: use -j only when is PARALLEL_JOBS is defined

When top-level parallel makefile is being used the PARALLEL_JOBS is empty but the build system of jack2 does not accept a -j without an argument so don't use the -j option when PARALLEL_JOBS is empty.

Fix build failure:
waf: error: -j option requires an argument
<snip>
make: *** [/home/tetsuya/buildroot/br2/output/build/jack2-ab409a65df95bc261ff72b52d6b3f4a65cf3266a/.stamp_built] Error 2

---
 package/jack2/jack2.mk | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

index 3f52ff4..a472df2 100644
@@ -10,6 +10,10 @@ JACK2_LICENSE = GPLv2+ (jack server), LGPLv2.1+ (jack library)
 JACK2_DEPENDENCIES = libsamplerate libsndfile alsa-lib host-python
 JACK2_INSTALL_STAGING = YES
 
+ifneq ($(PARALLEL_JOBS),)
+ JACK2_PARALLEL_JOBS = -j$(PARALLEL_JOBS)
+endif
+
 define JACK2_CONFIGURE_CMDS
 	(cd $(@D); \
 		$(TARGET_CONFIGURE_OPTS)	\

@@ -20,7 +24,8 @@ define JACK2_CONFIGURE_CMDS
 endef
 
 define JACK2_BUILD_CMDS
-	(cd $(@D); $(HOST_DIR)/usr/bin/python2 ./waf build -j $(PARALLEL_JOBS))
+	(cd $(@D); $(HOST_DIR)/usr/bin/python2 \
+		./waf build $(JACK2_PARALLEL_JOBS))
 endef
 
 define JACK2_INSTALL_TARGET_CMDS

2.3.4

When top-level parallel makefile is being used the PARALLEL_JOBS is empty but the b2 command of boost does not accept a -j without an argument so don't use the -j option when PARALLEL_JOBS is empty.

Fix install failure:
Invalid value for the '-j' option, valid values are 1 through 256.
make: *** [/home/tetsuya/buildroot/br2/output/build/boost-1.57.0/.stamp_staging_installed] Error 1

---
 package/boost/boost.mk | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

index 56a6c34..a8f5c9a 100644
@@ -23,6 +23,10 @@ HOST_BOOST_FLAGS = --without-icu \
 	iostreams locale log math mpi program_options python random regex \
 	serialization signals system test thread timer wave)
 
+ifneq ($(PARALLEL_JOBS),)
+BOOST_PARALLEL_JOBS = -j$(PARALLEL_JOBS)
+endif
+
 # coroutine breaks on some weak toolchains and it's new for 1.54+
 BOOST_WITHOUT_FLAGS = coroutine
 

@@ -121,7 +125,7 @@ define HOST_BOOST_CONFIGURE_CMDS
 endef
 
 define BOOST_INSTALL_TARGET_CMDS
-	(cd $(@D) && ./b2 -j$(PARALLEL_JOBS) -q -d+1 \
+	(cd $(@D) && ./b2 $(BOOST_PARALLEL_JOBS) -q -d+1 \
 	--user-config=$(@D)/user-config.jam \
 	$(BOOST_OPTS) \
 	--prefix=$(TARGET_DIR)/usr \

@@ -130,7 +134,7 @@ define BOOST_INSTALL_TARGET_CMDS
 endef
 
 define HOST_BOOST_BUILD_CMDS
-	(cd $(@D) && ./b2 -j$(PARALLEL_JOBS) -q -d+1 \
+	(cd $(@D) && ./b2 $(BOOST_PARALLEL_JOBS) -q -d+1 \
 	--user-config=$(@D)/user-config.jam \
 	$(HOST_BOOST_OPTS) \
 	--ignore-site-config \

@@ -138,7 +142,7 @@ define HOST_BOOST_BUILD_CMDS
 endef
 
 define HOST_BOOST_INSTALL_CMDS
-	(cd $(@D) && ./b2 -j$(PARALLEL_JOBS) -q -d+1 \
+	(cd $(@D) && ./b2 $(BOOST_PARALLEL_JOBS) -q -d+1 \
 	--user-config=$(@D)/user-config.jam \
 	$(HOST_BOOST_OPTS) \
 	--prefix=$(HOST_DIR)/usr \

@@ -147,7 +151,7 @@ define HOST_BOOST_INSTALL_CMDS
 endef
 
 define BOOST_INSTALL_STAGING_CMDS
-	(cd $(@D) && ./bjam -j$(PARALLEL_JOBS) -d+1 \
+	(cd $(@D) && ./bjam $(BOOST_PARALLEL_JOBS) -d+1 \
 	--user-config=$(@D)/user-config.jam \
 	$(BOOST_OPTS) \
 	--prefix=$(STAGING_DIR)/usr \

2.3.4

Dear Fabio Porcedda,

This is not quite true. PARALLEL_JOBS is empty because your recommendation of using:

	make BR2_JLEVEL= -j$((`getconf _NPROCESSORS_ONLN`+1))

for top-level parallel build is maybe not the most appropriate one.

In addition, even when top-level parallel build is used, using purely sequential build in each package may not be the good solution. Imagine you have a number of packages to build, and one of them is particularly
long: if you don't build this package in parallel, the build time may be increased.

So I believe that with the introduction of top-level parallel build, we need a way of calculating a default reasonable BR2_JLEVEL, preferably taking into account the make -jX value passed to the top-level make. We indeed need to play on the number of jobs at the top-level, and the number of jobs at the per-package level.

Also, your patch series does not handle all packages that use $(PARALLEL_JOBS) :

package/boost/boost.mk: (cd $(@D) && ./b2 -j$(PARALLEL_JOBS) -q -d+1 \
package/boost/boost.mk: (cd $(@D) && ./b2 -j$(PARALLEL_JOBS) -q -d+1 \
package/boost/boost.mk: (cd $(@D) && ./b2 -j$(PARALLEL_JOBS) -q -d+1 \
package/boost/boost.mk: (cd $(@D) && ./bjam -j$(PARALLEL_JOBS) -d+1 \
package/cmake/cmake.mk:                 --parallel=$(PARALLEL_JOBS) -- \
package/jack2/jack2.mk: (cd $(@D); $(HOST_DIR)/usr/bin/python2 ./waf build -j $(PARALLEL_JOBS))
package/midori/midori.mk:       (cd $(@D); $(HOST_DIR)/usr/bin/python2 ./waf build -j $(PARALLEL_JOBS))
package/qt/qt.mk:               MAKEFLAGS="$(MAKEFLAGS) -j$(PARALLEL_JOBS)" ./configure \
package/qt5/qt5base/qt5base.mk:         MAKEFLAGS="$(MAKEFLAGS) -j$(PARALLEL_JOBS)" \

We probably need to convert all of these to:

	$(if $(PARALLEL_JOBS),-j$(PARALLEL_JOBS))

like is done for the global $(MAKE) variable.

Best regards,

Thomas

Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

Good idea!

About taking in account the value passed to -j i don't know an automatic way to do it.

At least checking the MAKEFLAGS we can know if the -j options was used so we can use something like this:

index 803b162..698626f 100644
@@ -18,7 +18,7 @@ PARALLEL_JOBS := $(BR2_JLEVEL)
 endif
 
 MAKE1 := $(HOSTMAKE) -j1
-MAKE := $(HOSTMAKE) $(if $(PARALLEL_JOBS),-j$(PARALLEL_JOBS))
+override MAKE = $(HOSTMAKE) $(if $(findstring j,$(filter-out
--%,$(MAKEFLAGS))),,-j$(PARALLEL_JOBS))
 
 ifeq ($(BR2_TOOLCHAIN_BUILDROOT),y)

TARGET_VENDOR = $(call qstrip,$(BR2_TOOLCHAIN_BUILDROOT_VENDOR))

With this change we use can use the followin command line:
make -jX

That way we don't need to set as empty the BR2_JLEVEL variable and we can leave unchanged the lines that use the PARALLEL_JOBS variable.

You are right.

Thanks for reviewing.

Fabio Porcedda