test: Add test for memory snapshots

Two args (optional) -- number of snaps (3 defail) and pause
between them (4 defail).

Uses memory toucher from zdtm/.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

test/mem-snap/run.sh

+#!/bin/bash
+
+NRSNAP=${1:-3}
+SPAUSE=${2:-4}
+
+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 snapshots"
+
+for SNAP in $(seq 1 $NRSNAP); do
+	sleep $SPAUSE
+	mkdir "$IMGDIR/$SNAP/"
+	if [ $SNAP -eq 1 ] ; then
+		# First snapshot -- no parent, keep running
+		args="--snapshot -R"
+	elif [ $SNAP -eq $NRSNAP ]; then
+		# Last snapshot -- has parent, kill afterwards
+		args="--snapshot=../$((SNAP - 1))/"
+	else
+		# Other snapshots -- have parent, keep running
+		args="--snapshot=../$((SNAP - 1))/ -R"
+	fi
+
+	${CRTOOLS} dump -D "${IMGDIR}/$SNAP/" -o dump.log -t ${PID} $args || fail "Fail to dump"
+done
+
+echo "Restoring"
+${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"