[coreboot] New patch to review for coreboot: 991d040 abuild: Build boards in parallel if possible

[Patrick Georgi]

Patrick Georgi ([e-mail]) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/409

-gerrit

commit 991d0403fc05ab37d61078d98a6edd9245137c54
Author: Patrick Georgi 
Date:   Sat Nov 5 14:44:41 2011 +0100

abuild: Build boards in parallel if possible

Determine if xargs -P works. If yes, use that to build multiple
    boards in parallel, instead of relying on make -j X, when doing
    a full abuild run (instead of single boards).

make -j X isn't able to make use of several cores at various
    serialization points in our build process, so this change results
    in a >25% speed up for a full abuild run in my tests.

Change-Id: Id484a4211c84a3a24115278e0fbe92345f346596
    Signed-off-by: Patrick Georgi 
---
 util/abuild/abuild |   49 ++++++++++++++++++++++++++++++++++++++++---------
 1 files changed, 40 insertions(+), 9 deletions(-)

diff --git a/util/abuild/abuild b/util/abuild/abuild
index 8b81ea1..5228cdb 100755
--- a/util/abuild/abuild
+++ b/util/abuild/abuild
@@ -583,6 +583,9 @@ test -f util/sconfig/sconfig.l && ROOT=$( pwd )
 test -f ../util/sconfig/sconfig.l && ROOT=$( cd ..; pwd )
 test "$ROOT" = "" && ROOT=$( cd ../..; pwd )

+# command line for xargs parallelization. Thus overwrite -c X
+cmdline="$* -c 1"
+
 # parse parameters.. try to find out whether we're running GNU getopt
 getoptbrand="`getopt -V`"
 if [ "${getoptbrand:0:6}" == "getopt" ]; then
@@ -628,8 +631,43 @@ while true ; do
    esac
 done

+USE_XARGS=0
 if [ "$cpus" != "1" ]; then
-	export MAKEFLAGS="-j $cpus"
+	if [ "$target" = "" ]; then
+		# Test if xargs supports the non-standard -P flag
+		echo | xargs -P 0$cpus -n 1 echo 2>/dev/null >/dev/null && USE_XARGS=1
+	fi
+fi
+
+if [ "$USE_XARGS" = "0" ]; then
+export MAKEFLAGS="-j $cpus"
+build_all_targets()
+{
+	for VENDOR in $( vendors ); do
+		for MAINBOARD in $( mainboards $VENDOR ); do
+			build_target $VENDOR $MAINBOARD
+			test_target $VENDOR $MAINBOARD
+			remove_target $VENDOR $MAINBOARD
+		done
+	done
+}
+else
+# Limit to 32 parallel builds for now.
+# Thrashing all caches because we run
+# 160 abuilds in parallel is no fun.
+if [ "$cpus" = "" ]; then
+	cpus=32
+fi
+build_all_targets()
+{
+	# seed shared utils
+	MAKEFLAGS="-j $cpus" $0 $cmdline -t emulation/qemu-x86
+	for VENDOR in $( vendors ); do
+		for MAINBOARD in $( mainboards $VENDOR ); do
+			echo $VENDOR/$MAINBOARD
+		done
+	done | xargs -P 0$cpus -n 1 $0 $cmdline -t
+}
 fi

# /path/to/freebios2/
@@ -659,14 +697,7 @@ if [ "$target" != "" ]; then
    cat $TARGET/${VENDOR}_${MAINBOARD}/abuild.xml >> $REAL_XMLFILE
    XMLFILE=$REAL_XMLFILE
 else
-	# build all boards per default
-	for VENDOR in $( vendors ); do
-		for MAINBOARD in $( mainboards $VENDOR ); do
-			build_target $VENDOR $MAINBOARD
-			test_target $VENDOR $MAINBOARD
-			remove_target $VENDOR $MAINBOARD
-		done
-	done
+	build_all_targets
    for xmlfile in $TARGET/*_*/abuild.xml; do
    	cat $xmlfile >> $REAL_XMLFILE
    done