torture: Permit running of experimental torture types

This commit weakens the checks of the kvm.sh script's --torture parameter
and the kvm-recheck.sh script's parsing so that experimental torture tests
may be created without updating these two scripts.  The changes required
are to the appropriate Makefile and Kconfig file, plus a directory
whose name begins with "X" must be added to the rcutorture/configs file.
This new directory's name can then be passed in via the kvm.sh script's
--torture parameter.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

tools/testing/selftests/rcutorture/bin/kvm-recheck.sh

@@ -33,7 +33,12 @@ do
 		TORTURE_SUITE="`cat $i/../torture_suite`"
 		configfile=`echo $i | sed -e 's,^.*/,,'`
 		rm -f $i/console.log.*.diags
-		kvm-recheck-${TORTURE_SUITE}.sh $i
+		case "${TORTURE_SUITE}" in
+		X*)
+			;;
+		*)
+			kvm-recheck-${TORTURE_SUITE}.sh $i
+		esac
 		if test -f "$i/qemu-retval" && test "`cat $i/qemu-retval`" -ne 0 && test "`cat $i/qemu-retval`" -ne 137
 		then
 			echo QEMU error, output:

tools/testing/selftests/rcutorture/bin/kvm.sh

@@ -86,7 +86,7 @@ usage () {
 	echo "       --remote"
 	echo "       --results absolute-pathname"
 	echo "       --shutdown-grace seconds"
-	echo "       --torture lock|rcu|rcuscale|refscale|scf"
+	echo "       --torture lock|rcu|rcuscale|refscale|scf|X*"
 	echo "       --trust-make"
 	exit 1
 }
@@ -231,7 +231,7 @@ do
 		shift
 		;;
 	--torture)
-		checkarg --torture "(suite name)" "$#" "$2" '^\(lock\|rcu\|rcuscale\|refscale\|scf\)$' '^--'
+		checkarg --torture "(suite name)" "$#" "$2" '^\(lock\|rcu\|rcuscale\|refscale\|scf\|X.*\)$' '^--'
 		TORTURE_SUITE=$2
 		TORTURE_MOD="`echo $TORTURE_SUITE | sed -e 's/^\(lock\|rcu\|scf\)$/\1torture/'`"
 		shift