test: Add two tests for pre-dump action

The first is similar to existing snapshot test -- it calls
several pre-dumps on memory-changing zdtm test, then dumps
and check restore goes OK.

The second test is aimed at measuring frozen-time -- it
takes zdtm test with big mappings, dumps one, then start the
test again and calls one pre-dump plus dump. The sum of
frozen times in the 2nd dump (well, pre-dump + dump) should
be much smaller then the one of the 1st "just dump".
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

test/mem-snap/run-predump-2.sh

+#!/bin/bash
+
+function fail {
+	echo "$@"
+	exit 1
+}
+set -x
+
+CRTOOLS="../../crtools"
+IMGDIR="dump/"
+
+rm -rf "$IMGDIR"
+mkdir "$IMGDIR"
+
+function launch_test {
+	echo "Launching test"
+	cd ../zdtm/live/static/
+	make cleanout
+	make maps04
+	make maps04.pid || fail "Can't start test"
+	PID=$(cat maps04.pid)
+	kill -0 $PID || fail "Test didn't start"
+	cd -
+}
+
+function stop_test {
+	wtime=1
+	cd ../zdtm/live/static/
+	make maps04.out
+	while [ ! -f maps04.out ]; do echo "Wait for maps04.out"; sleep $wtime; ((wtime++)); done
+	cat maps04.out | fgrep PASS || fail "Test failed"
+	echo "OK"
+}
+
+launch_test
+
+echo "Taking plain dump"
+
+mkdir "$IMGDIR/dump-1/"
+${CRTOOLS} dump -D "$IMGDIR/dump-1/" -o dump.log -t ${PID} -v 4 || fail "Fail to dump"
+
+sleep 1
+echo "Restore to check it works"
+${CRTOOLS} restore -D "${IMGDIR}/dump-1/" -o restore.log -d -v 4 || fail "Fail to restore server"
+
+stop_test
+
+
+launch_test
+
+echo "Taking pre and plain dumps"
+
+echo "Pre-dump"
+mkdir "$IMGDIR/dump-2/"
+mkdir "$IMGDIR/dump-2/pre/"
+${CRTOOLS} pre-dump -D "$IMGDIR/dump-2/pre/" -o dump.log -t ${PID} -v 4 || fail "Fail to pre-dump"
+
+echo "Plain dump"
+mkdir "$IMGDIR/dump-2/plain/"
+${CRTOOLS} dump -D "$IMGDIR/dump-2/plain/" -o dump.log -t ${PID} -v 4 --prev-images-dir=../pre/ || fail "Fail to dump"
+
+sleep 1
+echo "Restore"
+${CRTOOLS} restore -D "${IMGDIR}/dump-2/plain/" -o restore.log -d -v 4 || fail "Fail to restore server"
+
+stop_test

test/mem-snap/run-predump.sh

+#!/bin/bash
+
+USEPS=0
+
+if [ "$1" = "-s" ]; then
+	echo "Will test via page-server"
+	USEPS=1
+	shift
+fi
+
+NRSNAP=${1:-3}
+SPAUSE=${2:-4}
+PORT=12345
+
+function fail {
+	echo "$@"
+	exit 1
+}
+set -x
+
+CRTOOLS="../../crtools"
+IMGDIR="dump/"
+
+rm -rf "$IMGDIR"
+mkdir "$IMGDIR"
+
+echo "Launching test"
+cd ../zdtm/live/static/
+make cleanout
+make mem-touch
+make mem-touch.pid || fail "Can't start test"
+PID=$(cat mem-touch.pid)
+kill -0 $PID || fail "Test didn't start"
+cd -
+
+echo "Making $NRSNAP pre-dumps"
+
+for SNAP in $(seq 1 $NRSNAP); do
+	sleep $SPAUSE
+	mkdir "$IMGDIR/$SNAP/"
+	if [ $SNAP -eq 1 ] ; then
+		# First pre-dump
+		cmd="pre-dump"
+		args="--track-mem -R"
+	elif [ $SNAP -eq $NRSNAP ]; then
+		# Last dump
+		cmd="dump"
+		args="--prev-images-dir=../$((SNAP - 1))/"
+	else
+		# Other pre-dumps
+		cmd="pre-dump"
+		args="--prev-images-dir=../$((SNAP - 1))/ --track-mem -R"
+	fi
+
+	if [ $USEPS -eq 1 ]; then
+		${CRTOOLS} page-server -D "${IMGDIR}/$SNAP/" -o ps.log --port ${PORT} -v 4 &
+		PS_PID=$!
+		ps_args="--page-server --address 127.0.0.1 --port=${PORT}"
+	else
+		ps_args=""
+	fi
+
+	${CRTOOLS} $cmd -D "${IMGDIR}/$SNAP/" -o dump.log -t ${PID} -v 4 $args $ps_args || fail "Fail to dump"
+	if [ $USEPS -eq 1 ]; then
+		wait $PS_PID
+	fi
+done
+
+echo "Restoring"
+${CRTOOLS} restore -D "${IMGDIR}/$NRSNAP/" -o restore.log -t ${PID} -d -v 4 || fail "Fail to restore server"
+
+cd ../zdtm/live/static/
+make mem-touch.out
+cat mem-touch.out | fgrep PASS || fail "Test failed"
+
+echo "Test PASSED"