torture: s/STOP/STOP.1/ to avoid scenario collision

This commit changes the "STOP" file that is used to cleanly halt a running
rcutorture run to "STOP.1" because no scenario directory will ever end
with ".1".  If there really was a scenario named "STOP", its directories
would instead be named "STOP", "STOP.2", "STOP.3", and so on.  While in
the area, the commit also changes the kernel-run-time checks for this
file to look directly in the directory above $resdir, thus avoiding the
need to pass the TORTURE_STOPFILE environment variable to remote systems.

While in the area, move the STOP.1 file to the top-level directory
covering all of the scenarios.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh

@@ -211,7 +211,7 @@ do
 		if test -n "$TORTURE_KCONFIG_GDB_ARG"
 		then
 			:
-		elif test $kruntime -ge $seconds || test -f "$TORTURE_STOPFILE"
+		elif test $kruntime -ge $seconds || test -f "$resdir/../STOP.1"
 		then
 			break;
 		fi
@@ -254,16 +254,16 @@ then
 fi
 if test $commandcompleted -eq 0 -a -n "$qemu_pid"
 then
-	if ! test -f "$TORTURE_STOPFILE"
+	if ! test -f "$resdir/../STOP.1"
 	then
 		echo Grace period for qemu job at pid $qemu_pid
 	fi
 	oldline="`tail $resdir/console.log`"
 	while :
 	do
-		if test -f "$TORTURE_STOPFILE"
+		if test -f "$resdir/../STOP.1"
 		then
-			echo "PID $qemu_pid killed due to run STOP request" >> $resdir/Warnings 2>&1
+			echo "PID $qemu_pid killed due to run STOP.1 request" >> $resdir/Warnings 2>&1
 			kill -KILL $qemu_pid
 			break
 		fi

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

@@ -386,7 +386,7 @@ then
 fi
 mkdir -p $resdir/$ds
 TORTURE_RESDIR="$resdir/$ds"; export TORTURE_RESDIR
-TORTURE_STOPFILE="$resdir/$ds/STOP"; export TORTURE_STOPFILE
+TORTURE_STOPFILE="$resdir/$ds/STOP.1"; export TORTURE_STOPFILE
 echo Results directory: $resdir/$ds
 echo $scriptname $args
 touch $resdir/$ds/log