[PATCH 2/2] builddeb: parallelize debug module installation

From: Chris J Arges
Date: Mon May 11 2015 - 10:02:40 EST


When building the dbg package, we use a large 'for module in $(find' loop that
can be easily parallelized by using 'find | xargs'. This patch modifies this
loop to use the later paradigm.

In addition, check if the user has requested a parallel build with make. If so,
add the appropriate flags to xargs to set MAXPROCS (-P) equal to the number of
processing units on the system.

Signed-off-by: Chris J Arges <chris.j.arges@xxxxxxxxxxxxx>
---
scripts/package/builddeb | 19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/scripts/package/builddeb b/scripts/package/builddeb
index 88dbf23..5849f0c 100755
--- a/scripts/package/builddeb
+++ b/scripts/package/builddeb
@@ -152,16 +152,21 @@ if grep -q '^CONFIG_MODULES=y' $KCONFIG_CONFIG ; then
rmdir "$tmpdir/lib/modules/$version"
fi
if [ -n "$BUILD_DEBUG" ] ; then
- for module in $(find $tmpdir/lib/modules/ -name *.ko -printf '%P\n'); do
- module=lib/modules/$module
- mkdir -p $(dirname $dbg_dir/usr/lib/debug/$module)
+ # If we've invoked make with -j, then parallelize; otherwise
+ # just use a single process.
+ procs=1
+ test "${MAKEFLAGS#*-j}" != "${MAKEFLAGS}" && procs=`getconf _NPROCESSORS_ONLN`
+ find $tmpdir/lib/modules/ -name *.ko -printf '%P\n' | xargs -n1 -P${procs} -I {} sh -c '
+ mkdir -p $(dirname '"$dbg_dir"'/usr/lib/debug/lib/modules/$1);'"
# only keep debug symbols in the debug file
- $OBJCOPY --only-keep-debug $tmpdir/$module $dbg_dir/usr/lib/debug/$module
+ $OBJCOPY --only-keep-debug $tmpdir/lib/modules/{} \
+ $dbg_dir/usr/lib/debug/lib/modules/{};
# strip original module from debug symbols
- $OBJCOPY --strip-debug $tmpdir/$module
+ $OBJCOPY --strip-debug $tmpdir/lib/modules/{};
# then add a link to those
- $OBJCOPY --add-gnu-debuglink=$dbg_dir/usr/lib/debug/$module $tmpdir/$module
- done
+ $OBJCOPY --add-gnu-debuglink=$dbg_dir/usr/lib/debug/lib/modules/{} \
+ $tmpdir/lib/modules/{};
+ " -- {}
fi
fi

--
1.9.1

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