gitlab-ci: Use -j4 instead of -j$(proc)

The shared GitLab CI runners are configured for jobs making use of up
to 4 CPU cores, attempting to use more may overload them.

Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Olivier Fourdan <ofourdan@redhat.com>

.gitlab-ci.yml

@@ -18,7 +18,7 @@ variables:
     DEBIAN_VERSION: testing-slim
     DEBIAN_EXEC: 'bash .gitlab-ci/debian-install.sh'
 
-    DEBIAN_TAG: "2019-09-03"
+    DEBIAN_TAG: "2020-01-06"
     IMAGE_LOCAL: "$CI_REGISTRY_IMAGE/debian/$DEBIAN_VERSION:$DEBIAN_TAG"
 
 include:
@@ -70,8 +70,8 @@ autotools-build-and-test:
         - mkdir build/
         - cd build/
         - ../autogen.sh --prefix=/usr
-        - make -j$(nproc) distcheck
-        - PIGLIT_DIR=/root/piglit XTEST_DIR=/root/xts make -j$(nproc) check
+        - make -j4 distcheck
+        - PIGLIT_DIR=/root/piglit XTEST_DIR=/root/xts make -j4 check
         - cd ..
         - .gitlab-ci/manpages-check
 
@@ -82,6 +82,6 @@ meson-build-and-test:
         XTEST_DIR: /root/xts
     script:
         - meson -Dprefix=/usr -Dxephyr=true build/
-        - ninja -C build/ install
-        - ninja -C build/ test
+        - ninja -j4 -C build/ install
+        - ninja -j4 -C build/ test
         - .gitlab-ci/manpages-check

.gitlab-ci/debian-install.sh

@@ -20,13 +20,13 @@ git clone https://gitlab.freedesktop.org/mesa/piglit.git --depth 1
 git clone https://gitlab.freedesktop.org/xorg/test/xts --depth 1
 cd xts
 ./autogen.sh
-xvfb-run make -j$(nproc)
+xvfb-run make -j4
 cd ..
 
 git clone https://gitlab.freedesktop.org/xorg/test/rendercheck --depth 1
 cd rendercheck
 meson build
-ninja -C build install
+ninja -j4 -C build install
 cd ..
 
 rm -rf piglit/.git xts/.git