4.9-rt: add script to auto create bisect branches

Sample usage:

	mkdir rt-test
	cd rt-test
	# clone mainline or clone from a local copy with >=4.9 tags in it.
	git clone /path/to/my/existing/mainline/linux linux-rt-bisect
	git clone git://git.kernel.org/pub/scm/linux/kernel/git/paulg/4.9-rt-patches.git
	cd linux-rt-bisect
	../4.9-rt-patches.git/scripts/create-branches.sh

1 files changed, 157 insertions, 0 deletions

diff --git a/scripts/create-branches.sh b/scripts/create-branches.sh
new file mode 100755
index 00000000000000..b9da8a8e65f778
--- /dev/null
+++ b/scripts/create-branches.sh
@@ -0,0 +1,157 @@
+#!/bin/bash
+
+# Create an -rt branch on top of each incremental merge in mainline by Linus.
+
+# Assumes patches for merge "v4.x-gabcdef" are on tag "rt-v4.x-gabcdef" in
+# the $PATCHES repo.
+
+START=v4.8
+END=v4.9
+RC=8
+
+# Collect path info and then clone ourselves and fork.
+if [ -z "$KERNEL" ]; then
+	echo "Path to existing mainline kernel repo where you want the rt bisect branches."
+	echo -n "(e.g.  \"/home/paul/git/linux-rt-bisect\") Default is \"./\": "
+	read KERNEL
+	if [ -z "$KERNEL" ]; then
+		KERNEL="./"
+	fi
+
+	KERNEL=`readlink -f $KERNEL`
+	if [ ! -d "$KERNEL"/.git ]; then
+		echo Entry $KERNEL does not appear to be a git repo
+		exit 1
+	fi
+
+	PATCHES=`dirname $0 | sed 's/scripts/patches/'`
+	PATCHES=`readlink -f $PATCHES`
+
+	# We'll check out tags where we don't exist; so copy ourselves.
+	SCRIPT=`mktemp`
+	echo '#!/bin/bash' > $SCRIPT
+	echo SCRIPT=$SCRIPT >> $SCRIPT
+	echo KERNEL=$KERNEL >> $SCRIPT
+	echo PATCHES=$PATCHES >> $SCRIPT
+	cat $0 | grep -v '^#!/bin/bash' >> $SCRIPT
+	chmod +x $SCRIPT
+	exec $SCRIPT
+fi
+
+MERGES=`mktemp`
+DMERGES=`mktemp`
+MAPPING=`mktemp`
+LOG=`mktemp`
+
+echo Logging debug and errors to $LOG
+# echo Mapping of merges to patch tags in $MAPPING
+
+cd $PATCHES > $LOG 2>&1
+if [ $? != 0 ]; then
+	echo Can not cd into $PATCHES
+	exit 1
+fi
+
+git checkout $END-rt >> $LOG 2>&1
+if [ $? != 0 ];then
+	echo Checkout of $END-rt in $PATCHES failed
+	exit 1
+fi
+
+if [ ! -f $PATCHES/series ]; then
+	echo Can not find series file in $PATCHES
+	exit 1
+fi
+
+cd $KERNEL >> $LOG 2>&1
+if [ $? != 0 ]; then
+	echo Can not cd into $KERNEL
+	exit 1
+fi
+
+# Sanity check
+git rev-parse $START >> $LOG 2>&1
+if [ $? != 0 ]; then
+	echo Cant resolve $START in $KERNEL
+	exit 1
+fi
+git rev-parse $END >> $LOG 2>&1
+if [ $? != 0 ]; then
+	echo Cant resolve $END in $KERNEL
+	exit 1
+fi
+
+echo "Getting merges.."
+git log --oneline --merges --author=Torvalds --reverse ^$START $END-rc1 | awk '{print $1}' > $MERGES
+
+# post rc1 we dont do it per merge, just per rc tag.
+for i in `seq $RC` ; do echo $END-rc$i >> $MERGES ; done
+echo $END >> $MERGES
+MCOUNT=`cat $MERGES | wc -l`
+
+echo -n "Describing $MCOUNT merges"
+for i in `cat $MERGES` ; do
+	git describe $i >> $DMERGES
+	echo -n .
+done
+echo done.
+
+echo $START $START.0-rt > $MAPPING
+PTAG=rt-START.0
+
+cd $PATCHES
+# echo "Mapping $MCOUNT merges to patch repo tags."
+for i in `cat $DMERGES` ; do
+
+	git tag | grep -q $i
+
+	if [ $? = 0 ]; then	# patch tag match for this merge
+		PTAG=rt-$i
+	fi
+
+	echo $i $PTAG >> $MAPPING
+done
+
+HERE=1
+for i in `cat $DMERGES` ; do
+
+	PTAG=`grep "^$i " $MAPPING | awk '{print $2}'`
+	echo "[$HERE/$MCOUNT] Applying $PTAG to $i in $KERNEL" >> $LOG
+
+	cd $PATCHES
+	git checkout $PTAG >> $LOG 2>&1
+	if [ $? != 0 ];then
+		echo Checkout of $PTAG in $PATCHES failed
+		exit 1
+	fi
+
+	cd $KERNEL
+	git checkout -b $i-rt $i >> $LOG 2>&1
+	if [ $? != 0 ];then
+		echo New branch of $i-rt in $KERNEL failed
+		exit
+	fi
+
+	COUNT=`cat $PATCHES/series | grep '^[a-zA-Z0-9_]' | wc -l`
+	echo "[$HERE/$MCOUNT] Applying $PTAG ($COUNT patches) to $i baseline"
+	for i in `cat $PATCHES/series | grep '^[a-zA-Z0-9_]'`; do
+		git am $PATCHES/$i >> $LOG 2>&1
+		if [ $? != 0 ]; then
+			echo Git am of $PATCHES/$i failed
+			exit 1
+		fi
+	done
+
+	HERE=$[$HERE+1]
+done
+
+cd $PATCHES
+git checkout $END-rt >> $LOG 2>&1
+cd $KERNEL
+
+# rm -f $LOG
+rm -f $MERGES
+rm -f $DMERGES
+rm -f $MAPPING
+# Finally, remove ourselves.
+rm -f $SCRIPT