'make srcdeb-pkg' generates a source package, which you can build
later by using dpkg-buildpackage.
In older dpkg versions, 'dpkg-buildpackage -j N' sets not only
DEB_BUILD_OPTIONS but also MAKEFLAGS. Hence, passing -j (--jobs)
to dpkg-buildpackage was enough to run parallel building.
The behavior was changed by commit 1d0ea9b2ba3f ("dpkg-buildpackage:
Change -j, --jobs semantics to non-force mode") of dpkg project. [1]
Since then, 'dpkg-buildpackage -j N' sets only DEB_BUILD_OPTIONS,
which is not parsed by the current debian/rules. You cannot build it
in parallel unless you pass --jobs-force instead or set the MAKEFLAGS
environment variable.
Debian policy [2] suggests the following code snippet for debian/rules.
ifneq (,$(filter parallel=%,$(DEB_BUILD_OPTIONS)))
NUMJOBS = $(patsubst parallel=%,%,$(filter parallel=%,$(DEB_BUILD_OPTIONS)))
MAKEFLAGS += -j$(NUMJOBS)
endif
I added slightly different code to debian/rules so 'make -j N deb-pkg'
works as before. In this case, the '-j N' should not be specified in
debian/rules again. 'make deb-pkg' without the -j option must explicitly
pass -j1 to dpkb-buildpackage because otherwise DEB_BUILD_OPTIONS
contains parallel=<nproc> by default.
This should work with almost all Make versions Kbuild supports.
Only the corner case I found not working is 'make-3.82 -j deb-pkg',
which results in single thread building. It is not a big deal because
-j without an argument, which does not limit the number of jobs, is
rarely used.
As far as I tested, the MAKEFLAGS format varies by Make versions.
command line option $(MAKEFLAGS) in recipe
Make 3.82 -j j
-j1 <none>
-j2 -j
Make 4.0/4.1 -j -j
-j1 <none>
-j2 -j
Make 4.2+ -j -j
-j1 -j1
-j2 -j2
[1] https://salsa.debian.org/dpkg-team/dpkg/-/commit/1d0ea9b2ba3f6a2de5b1a6ff55f3df7b71f73db6
[2] https://www.debian.org/doc/debian-policy/ch-source.html#s-debianrules-options
Reported-by: Bastian Germann <bage@xxxxxxxxxxxxx>
Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
---
scripts/Makefile.package | 4 +++-
scripts/package/debian/rules | 8 +++++---
2 files changed, 8 insertions(+), 4 deletions(-)
diff --git a/scripts/Makefile.package b/scripts/Makefile.package
index f8a948ec2c6b..f8b9ba4705c8 100644
--- a/scripts/Makefile.package
+++ b/scripts/Makefile.package
@@ -148,7 +148,9 @@ deb-pkg srcdeb-pkg bindeb-pkg:
$(if $(findstring source, $(build-type)), \
--unsigned-source --compression=$(KDEB_SOURCE_COMPRESS)) \
$(if $(findstring binary, $(build-type)), \
- --rules-file='$(MAKE) -f debian/rules' -r$(KBUILD_PKG_ROOTCMD) -a$$(cat debian/arch), \
+ --rules-file='$(MAKE) -f debian/rules' \
+ $(if $(filter-out -j1,$(filter -j%,$(MAKEFLAGS))),,--jobs=1) \
+ -r$(KBUILD_PKG_ROOTCMD) -a$$(cat debian/arch), \
--no-check-builddeps) \
$(DPKG_FLAGS))
diff --git a/scripts/package/debian/rules b/scripts/package/debian/rules
index 226e127efd63..4753173daaae 100755
--- a/scripts/package/debian/rules
+++ b/scripts/package/debian/rules
@@ -5,11 +5,13 @@ include debian/rules.vars
srctree ?= .
+JOBS = $(if $(filter -j%,$(MAKEFLAGS)),,$(patsubst parallel=%,-j%,$(filter parallel=%,$(DEB_BUILD_OPTIONS))))
+
.PHONY: binary binary-indep binary-arch
binary: binary-arch binary-indep
binary-indep: build-indep
binary-arch: build-arch
- $(MAKE) -f $(srctree)/Makefile ARCH=$(ARCH) \
+ $(MAKE) $(JOBS) -f $(srctree)/Makefile ARCH=$(ARCH) \
KERNELRELEASE=$(KERNELRELEASE) \
run-command KBUILD_RUN_COMMAND=+$(srctree)/scripts/package/builddeb
@@ -17,7 +19,7 @@ binary-arch: build-arch
build: build-arch build-indep
build-indep:
build-arch:
- $(MAKE) -f $(srctree)/Makefile ARCH=$(ARCH) \
+ $(MAKE) $(JOBS) -f $(srctree)/Makefile ARCH=$(ARCH) \
KERNELRELEASE=$(KERNELRELEASE) \
$(shell $(srctree)/scripts/package/deb-build-option) \
olddefconfig all
@@ -25,4 +27,4 @@ build-arch:
.PHONY: clean
clean:
rm -rf debian/files debian/linux-*
- $(MAKE) -f $(srctree)/Makefile ARCH=$(ARCH) clean
+ $(MAKE) $(JOBS) -f $(srctree)/Makefile ARCH=$(ARCH) clean
--
2.39.2
