Merge tag 'core-rcu-2021-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RCU updates from Ingo Molnar:

 - Support for "N" as alias for last bit in bitmap parsing library (eg
   using syntax like "nohz_full=2-N")

 - kvfree_rcu updates

 - mm_dump_obj() updates. (One of these is to mm, but was suggested by
   Andrew Morton.)

 - RCU callback offloading update

 - Polling RCU grace-period interfaces

 - Realtime-related RCU updates

 - Tasks-RCU updates

 - Torture-test updates

 - Torture-test scripting updates

 - Miscellaneous fixes

* tag 'core-rcu-2021-04-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (77 commits)
  rcutorture: Test start_poll_synchronize_rcu() and poll_state_synchronize_rcu()
  rcu: Provide polling interfaces for Tiny RCU grace periods
  torture: Fix kvm.sh --datestamp regex check
  torture: Consolidate qemu-cmd duration editing into kvm-transform.sh
  torture: Print proper vmlinux path for kvm-again.sh runs
  torture: Make TORTURE_TRUST_MAKE available in kvm-again.sh environment
  torture: Make kvm-transform.sh update jitter commands
  torture: Add --duration argument to kvm-again.sh
  torture: Add kvm-again.sh to rerun a previous torture-test
  torture: Create a "batches" file for build reuse
  torture: De-capitalize TORTURE_SUITE
  torture: Make upper-case-only no-dot no-slash scenario names official
  torture: Rename SRCU-t and SRCU-u to avoid lowercase characters
  torture: Remove no-mpstat error message
  torture: Record kvm-test-1-run.sh and kvm-test-1-run-qemu.sh PIDs
  torture: Record jitter start/stop commands
  torture: Extract kvm-test-1-run-qemu.sh from kvm-test-1-run.sh
  torture: Record TORTURE_KCONFIG_GDB_ARG in qemu-cmd
  torture: Abstract jitter.sh start/stop into scripts
  rcu: Provide polling interfaces for Tree RCU grace periods
  ...

22 files changed, 694 insertions, 216 deletions

diff --git a/tools/testing/selftests/rcutorture/bin/cpus2use.sh b/tools/testing/selftests/rcutorture/bin/cpus2use.sh
index 1dbfb62567d2..6bb993001680 100755
--- a/tools/testing/selftests/rcutorture/bin/cpus2use.sh
+++ b/tools/testing/selftests/rcutorture/bin/cpus2use.sh
@@ -21,7 +21,6 @@ then
 		awk -v ncpus=$ncpus '{ print ncpus * ($7 + $NF) / 100 }'`
 else
 	# No mpstat command, so use all available CPUs.
-	echo The mpstat command is not available, so greedily using all CPUs.
 	idlecpus=$ncpus
 fi
 awk -v ncpus=$ncpus -v idlecpus=$idlecpus < /dev/null '
diff --git a/tools/testing/selftests/rcutorture/bin/jitter.sh b/tools/testing/selftests/rcutorture/bin/jitter.sh
index 188b864bc4bf..15d937ba96ca 100755
--- a/tools/testing/selftests/rcutorture/bin/jitter.sh
+++ b/tools/testing/selftests/rcutorture/bin/jitter.sh
@@ -5,10 +5,11 @@
 # of this script is to inflict random OS jitter on a concurrently running
 # test.
 #
-# Usage: jitter.sh me duration [ sleepmax [ spinmax ] ]
+# Usage: jitter.sh me jittering-path duration [ sleepmax [ spinmax ] ]
 #
 # me: Random-number-generator seed salt.
 # duration: Time to run in seconds.
+# jittering-path: Path to file whose removal will stop this script.
 # sleepmax: Maximum microseconds to sleep, defaults to one second.
 # spinmax: Maximum microseconds to spin, defaults to one millisecond.
 #
@@ -17,9 +18,10 @@
 # Authors: Paul E. McKenney <paulmck@linux.ibm.com>
 
 me=$(($1 * 1000))
-duration=$2
-sleepmax=${3-1000000}
-spinmax=${4-1000}
+jittering=$2
+duration=$3
+sleepmax=${4-1000000}
+spinmax=${5-1000}
 
 n=1
 
@@ -47,7 +49,7 @@ do
 	fi
 
 	# Check for stop request.
-	if test -f "$TORTURE_STOPFILE"
+	if ! test -f "$jittering"
 	then
 		exit 1;
 	fi
@@ -67,10 +69,10 @@ do
 		srand(n + me + systime());
 		ncpus = split(cpus, ca);
 		curcpu = ca[int(rand() * ncpus + 1)];
-		mask = lshift(1, curcpu);
-		if (mask + 0 <= 0)
-			mask = 1;
-		printf("%#x\n", mask);
+		z = "";
+		for (i = 1; 4 * i <= curcpu; i++)
+			z = z "0";
+		print "0x" 2 ^ (curcpu % 4) z;
 	}' < /dev/null`
 	n=$(($n+1))
 	if ! taskset -p $cpumask $$ > /dev/null 2>&1
diff --git a/tools/testing/selftests/rcutorture/bin/jitterstart.sh b/tools/testing/selftests/rcutorture/bin/jitterstart.sh
new file mode 100644
index 000000000000..3d710ad291c3
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/bin/jitterstart.sh
@@ -0,0 +1,37 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Start up the specified number of jitter.sh scripts in the background.
+#
+# Usage: . jitterstart.sh n jittering-dir duration [ sleepmax [ spinmax ] ]
+#
+# n: Number of jitter.sh scripts to start up.
+# jittering-dir: Directory in which to put "jittering" file.
+# duration: Time to run in seconds.
+# sleepmax: Maximum microseconds to sleep, defaults to one second.
+# spinmax: Maximum microseconds to spin, defaults to one millisecond.
+#
+# Copyright (C) 2021 Facebook, Inc.
+#
+# Authors: Paul E. McKenney <paulmck@kernel.org>
+
+jitter_n=$1
+if test -z "$jitter_n"
+then
+	echo jitterstart.sh: Missing count of jitter.sh scripts to start.
+	exit 33
+fi
+jittering_dir=$2
+if test -z "$jittering_dir"
+then
+	echo jitterstart.sh: Missing directory in which to place jittering file.
+	exit 34
+fi
+shift
+shift
+
+touch ${jittering_dir}/jittering
+for ((jitter_i = 1; jitter_i <= $jitter_n; jitter_i++))
+do
+	jitter.sh $jitter_i "${jittering_dir}/jittering" "$@" &
+done
diff --git a/tools/testing/selftests/rcutorture/bin/jitterstop.sh b/tools/testing/selftests/rcutorture/bin/jitterstop.sh
new file mode 100644
index 000000000000..576a4cf4b79a
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/bin/jitterstop.sh
@@ -0,0 +1,23 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Remove the "jittering" file, signaling the jitter.sh scripts to stop,
+# then wait for them to terminate.
+#
+# Usage: . jitterstop.sh jittering-dir
+#
+# jittering-dir: Directory containing "jittering" file.
+#
+# Copyright (C) 2021 Facebook, Inc.
+#
+# Authors: Paul E. McKenney <paulmck@kernel.org>
+
+jittering_dir=$1
+if test -z "$jittering_dir"
+then
+	echo jitterstop.sh: Missing directory in which to place jittering file.
+	exit 34
+fi
+
+rm -f ${jittering_dir}/jittering
+wait
diff --git a/tools/testing/selftests/rcutorture/bin/kvm-again.sh b/tools/testing/selftests/rcutorture/bin/kvm-again.sh
new file mode 100755
index 000000000000..46e47a00a7db
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/bin/kvm-again.sh
@@ -0,0 +1,199 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Rerun a series of tests under KVM.
+#
+# Usage: kvm-again.sh /path/to/old/run [ options ]
+#
+# Copyright (C) 2021 Facebook, Inc.
+#
+# Authors: Paul E. McKenney <paulmck@kernel.org>
+
+scriptname=$0
+args="$*"
+
+T=${TMPDIR-/tmp}/kvm-again.sh.$$
+trap 'rm -rf $T' 0
+mkdir $T
+
+if ! test -d tools/testing/selftests/rcutorture/bin
+then
+	echo $scriptname must be run from top-level directory of kernel source tree.
+	exit 1
+fi
+
+oldrun=$1
+shift
+if ! test -d "$oldrun"
+then
+	echo "Usage: $scriptname /path/to/old/run [ options ]"
+	exit 1
+fi
+if ! cp "$oldrun/batches" $T/batches.oldrun
+then
+	# Later on, can reconstitute this from console.log files.
+	echo Prior run batches file does not exist: $oldrun/batches
+	exit 1
+fi
+
+if test -f "$oldrun/torture_suite"
+then
+	torture_suite="`cat $oldrun/torture_suite`"
+elif test -f "$oldrun/TORTURE_SUITE"
+then
+	torture_suite="`cat $oldrun/TORTURE_SUITE`"
+else
+	echo "Prior run torture_suite file does not exist: $oldrun/{torture_suite,TORTURE_SUITE}"
+	exit 1
+fi
+
+KVM="`pwd`/tools/testing/selftests/rcutorture"; export KVM
+PATH=${KVM}/bin:$PATH; export PATH
+. functions.sh
+
+dryrun=
+dur=
+default_link="cp -R"
+rundir="`pwd`/tools/testing/selftests/rcutorture/res/`date +%Y.%m.%d-%H.%M.%S-again`"
+
+startdate="`date`"
+starttime="`get_starttime`"
+
+usage () {
+	echo "Usage: $scriptname $oldrun [ arguments ]:"
+	echo "       --dryrun"
+	echo "       --duration minutes | <seconds>s | <hours>h | <days>d"
+	echo "       --link hard|soft|copy"
+	echo "       --remote"
+	echo "       --rundir /new/res/path"
+	exit 1
+}
+
+while test $# -gt 0
+do
+	case "$1" in
+	--dryrun)
+		dryrun=1
+		;;
+	--duration)
+		checkarg --duration "(minutes)" $# "$2" '^[0-9][0-9]*\(s\|m\|h\|d\|\)$' '^error'
+		mult=60
+		if echo "$2" | grep -q 's$'
+		then
+			mult=1
+		elif echo "$2" | grep -q 'h$'
+		then
+			mult=3600
+		elif echo "$2" | grep -q 'd$'
+		then
+			mult=86400
+		fi
+		ts=`echo $2 | sed -e 's/[smhd]$//'`
+		dur=$(($ts*mult))
+		shift
+		;;
+	--link)
+		checkarg --link "hard|soft|copy" "$#" "$2" 'hard\|soft\|copy' '^--'
+		case "$2" in
+		copy)
+			arg_link="cp -R"
+			;;
+		hard)
+			arg_link="cp -Rl"
+			;;
+		soft)
+			arg_link="cp -Rs"
+			;;
+		esac
+		shift
+		;;
+	--remote)
+		arg_remote=1
+		default_link="cp -as"
+		;;
+	--rundir)
+		checkarg --rundir "(absolute pathname)" "$#" "$2" '^/' '^error'
+		rundir=$2
+		if test -e "$rundir"
+		then
+			echo "--rundir $2: Already exists."
+			usage
+		fi
+		shift
+		;;
+	*)
+		echo Unknown argument $1
+		usage
+		;;
+	esac
+	shift
+done
+if test -z "$arg_link"
+then
+	arg_link="$default_link"
+fi
+
+echo ---- Re-run results directory: $rundir
+
+# Copy old run directory tree over and adjust.
+mkdir -p "`dirname "$rundir"`"
+if ! $arg_link "$oldrun" "$rundir"
+then
+	echo "Cannot copy from $oldrun to $rundir."
+	usage
+fi
+rm -f "$rundir"/*/{console.log,console.log.diags,qemu_pid,qemu-retval,Warnings,kvm-test-1-run.sh.out,kvm-test-1-run-qemu.sh.out,vmlinux} "$rundir"/log
+echo $oldrun > "$rundir/re-run"
+if ! test -d "$rundir/../../bin"
+then
+	$arg_link "$oldrun/../../bin" "$rundir/../.."
+fi
+for i in $rundir/*/qemu-cmd
+do
+	cp "$i" $T
+	qemu_cmd_dir="`dirname "$i"`"
+	kernel_dir="`echo $qemu_cmd_dir | sed -e 's/\.[0-9]\+$//'`"
+	jitter_dir="`dirname "$kernel_dir"`"
+	kvm-transform.sh "$kernel_dir/bzImage" "$qemu_cmd_dir/console.log" "$jitter_dir" $dur < $T/qemu-cmd > $i
+	if test -n "$arg_remote"
+	then
+		echo "# TORTURE_KCONFIG_GDB_ARG=''" >> $i
+	fi
+done
+
+# Extract settings from the last qemu-cmd file transformed above.
+grep '^#' $i | sed -e 's/^# //' > $T/qemu-cmd-settings
+. $T/qemu-cmd-settings
+
+grep -v '^#' $T/batches.oldrun | awk '
+BEGIN {
+	oldbatch = 1;
+}
+
+{
+	if (oldbatch != $1) {
+		print "kvm-test-1-run-batch.sh" curbatch;
+		curbatch = "";
+		oldbatch = $1;
+	}
+	curbatch = curbatch " " $2;
+}
+
+END {
+	print "kvm-test-1-run-batch.sh" curbatch
+}' > $T/runbatches.sh
+
+if test -n "$dryrun"
+then
+	echo ---- Dryrun complete, directory: $rundir | tee -a "$rundir/log"
+else
+	( cd "$rundir"; sh $T/runbatches.sh )
+	kcsan-collapse.sh "$rundir" | tee -a "$rundir/log"
+	echo | tee -a "$rundir/log"
+	echo ---- Results directory: $rundir | tee -a "$rundir/log"
+	kvm-recheck.sh "$rundir" > $T/kvm-recheck.sh.out 2>&1
+	ret=$?
+	cat $T/kvm-recheck.sh.out | tee -a "$rundir/log"
+	echo " --- Done at `date` (`get_starttime_duration $starttime`) exitcode $ret" | tee -a "$rundir/log"
+	exit $ret
+fi
diff --git a/tools/testing/selftests/rcutorture/bin/kvm-recheck.sh b/tools/testing/selftests/rcutorture/bin/kvm-recheck.sh
index 47cf4db10896..e01b31b87044 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm-recheck.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm-recheck.sh
@@ -30,7 +30,7 @@ do
 			resdir=`echo $i | sed -e 's,/$,,' -e 's,/[^/]*$,,'`
 			head -1 $resdir/log
 		fi
-		TORTURE_SUITE="`cat $i/../TORTURE_SUITE`"
+		TORTURE_SUITE="`cat $i/../torture_suite`"
 		configfile=`echo $i | sed -e 's,^.*/,,'`
 		rm -f $i/console.log.*.diags
 		kvm-recheck-${TORTURE_SUITE}.sh $i
diff --git a/tools/testing/selftests/rcutorture/bin/kvm-test-1-run-batch.sh b/tools/testing/selftests/rcutorture/bin/kvm-test-1-run-batch.sh
new file mode 100755
index 000000000000..7ea0809e229e
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/bin/kvm-test-1-run-batch.sh
@@ -0,0 +1,67 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Carry out a kvm-based run for the specified batch of scenarios, which
+# might have been built by --build-only kvm.sh run.
+#
+# Usage: kvm-test-1-run-batch.sh SCENARIO [ SCENARIO ... ]
+#
+# Each SCENARIO is the name of a directory in the current directory
+#	containing a ready-to-run qemu-cmd file.
+#
+# Copyright (C) 2021 Facebook, Inc.
+#
+# Authors: Paul E. McKenney <paulmck@kernel.org>
+
+T=${TMPDIR-/tmp}/kvm-test-1-run-batch.sh.$$
+trap 'rm -rf $T' 0
+mkdir $T
+
+echo ---- Running batch $*
+# Check arguments
+runfiles=
+for i in "$@"
+do
+	if ! echo $i | grep -q '^[^/.a-z]\+\(\.[0-9]\+\)\?$'
+	then
+		echo Bad scenario name: \"$i\" 1>&2
+		exit 1
+	fi
+	if ! test -d "$i"
+	then
+		echo Scenario name not a directory: \"$i\" 1>&2
+		exit 2
+	fi
+	if ! test -f "$i/qemu-cmd"
+	then
+		echo Scenario lacks a command file: \"$i/qemu-cmd\" 1>&2
+		exit 3
+	fi
+	rm -f $i/build.*
+	touch $i/build.run
+	runfiles="$runfiles $i/build.run"
+done
+
+# Extract settings from the qemu-cmd file.
+grep '^#' $1/qemu-cmd | sed -e 's/^# //' > $T/qemu-cmd-settings
+. $T/qemu-cmd-settings
+
+# Start up jitter, start each scenario, wait, end jitter.
+echo ---- System running test: `uname -a`
+echo ---- Starting kernels. `date` | tee -a log
+$TORTURE_JITTER_START
+for i in "$@"
+do
+	echo ---- System running test: `uname -a` > $i/kvm-test-1-run-qemu.sh.out
+	echo > $i/kvm-test-1-run-qemu.sh.out
+	kvm-test-1-run-qemu.sh $i >> $i/kvm-test-1-run-qemu.sh.out 2>&1 &
+done
+for i in $runfiles
+do
+	while ls $i > /dev/null 2>&1
+	do
+		:
+	done
+done
+echo ---- All kernel runs complete. `date` | tee -a log
+$TORTURE_JITTER_STOP
diff --git a/tools/testing/selftests/rcutorture/bin/kvm-test-1-run-qemu.sh b/tools/testing/selftests/rcutorture/bin/kvm-test-1-run-qemu.sh
new file mode 100755
index 000000000000..5b1aa2a4f3f6
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/bin/kvm-test-1-run-qemu.sh
@@ -0,0 +1,176 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Carry out a kvm-based run for the specified qemu-cmd file, which might
+# have been generated by --build-only kvm.sh run.
+#
+# Usage: kvm-test-1-run-qemu.sh qemu-cmd-dir
+#
+# qemu-cmd-dir provides the directory containing qemu-cmd file.
+#	This is assumed to be of the form prefix/ds/scenario, where
+#	"ds" is the top-level date-stamped directory and "scenario"
+#	is the scenario name.  Any required adjustments to this file
+#	must have been made by the caller.  The shell-command comments
+#	at the end of the qemu-cmd file are not optional.
+#
+# Copyright (C) 2021 Facebook, Inc.
+#
+# Authors: Paul E. McKenney <paulmck@kernel.org>
+
+T=${TMPDIR-/tmp}/kvm-test-1-run-qemu.sh.$$
+trap 'rm -rf $T' 0
+mkdir $T
+
+resdir="$1"
+if ! test -d "$resdir"
+then
+	echo $0: Nonexistent directory: $resdir
+	exit 1
+fi
+if ! test -f "$resdir/qemu-cmd"
+then
+	echo $0: Nonexistent qemu-cmd file: $resdir/qemu-cmd
+	exit 1
+fi
+
+echo ' ---' `date`: Starting kernel, PID $$
+
+# Obtain settings from the qemu-cmd file.
+grep '^#' $resdir/qemu-cmd | sed -e 's/^# //' > $T/qemu-cmd-settings
+. $T/qemu-cmd-settings
+
+# Decorate qemu-cmd with redirection, backgrounding, and PID capture
+sed -e 's/$/ 2>\&1 \&/' < $resdir/qemu-cmd > $T/qemu-cmd
+echo 'echo $! > $resdir/qemu_pid' >> $T/qemu-cmd
+
+# In case qemu refuses to run...
+echo "NOTE: $QEMU either did not run or was interactive" > $resdir/console.log
+
+# Attempt to run qemu
+kstarttime=`gawk 'BEGIN { print systime() }' < /dev/null`
+( . $T/qemu-cmd; wait `cat  $resdir/qemu_pid`; echo $? > $resdir/qemu-retval ) &
+commandcompleted=0
+if test -z "$TORTURE_KCONFIG_GDB_ARG"
+then
+	sleep 10 # Give qemu's pid a chance to reach the file
+	if test -s "$resdir/qemu_pid"
+	then
+		qemu_pid=`cat "$resdir/qemu_pid"`
+		echo Monitoring qemu job at pid $qemu_pid
+	else
+		qemu_pid=""
+		echo Monitoring qemu job at yet-as-unknown pid
+	fi
+fi
+if test -n "$TORTURE_KCONFIG_GDB_ARG"
+then
+	base_resdir=`echo $resdir | sed -e 's/\.[0-9]\+$//'`
+	if ! test -f $base_resdir/vmlinux
+	then
+		base_resdir="`cat re-run`/$resdir"
+		if ! test -f $base_resdir/vmlinux
+		then
+			base_resdir=/path/to
+		fi
+	fi
+	echo Waiting for you to attach a debug session, for example: > /dev/tty
+	echo "    gdb $base_resdir/vmlinux" > /dev/tty
+	echo 'After symbols load and the "(gdb)" prompt appears:' > /dev/tty
+	echo "    target remote :1234" > /dev/tty
+	echo "    continue" > /dev/tty
+	kstarttime=`gawk 'BEGIN { print systime() }' < /dev/null`
+fi
+while :
+do
+	if test -z "$qemu_pid" -a -s "$resdir/qemu_pid"
+	then
+		qemu_pid=`cat "$resdir/qemu_pid"`
+	fi
+	kruntime=`gawk 'BEGIN { print systime() - '"$kstarttime"' }' < /dev/null`
+	if test -z "$qemu_pid" || kill -0 "$qemu_pid" > /dev/null 2>&1
+	then
+		if test -n "$TORTURE_KCONFIG_GDB_ARG"
+		then
+			:
+		elif test $kruntime -ge $seconds || test -f "$resdir/../STOP.1"
+		then
+			break;
+		fi
+		sleep 1
+	else
+		commandcompleted=1
+		if test $kruntime -lt $seconds
+		then
+			echo Completed in $kruntime vs. $seconds >> $resdir/Warnings 2>&1
+			grep "^(qemu) qemu:" $resdir/kvm-test-1-run.sh.out >> $resdir/Warnings 2>&1
+			killpid="`sed -n "s/^(qemu) qemu: terminating on signal [0-9]* from pid \([0-9]*\).*$/\1/p" $resdir/Warnings`"
+			if test -n "$killpid"
+			then
+				echo "ps -fp $killpid" >> $resdir/Warnings 2>&1
+				ps -fp $killpid >> $resdir/Warnings 2>&1
+			fi
+		else
+			echo ' ---' `date`: "Kernel done"
+		fi
+		break
+	fi
+done
+if test -z "$qemu_pid" -a -s "$resdir/qemu_pid"
+then
+	qemu_pid=`cat "$resdir/qemu_pid"`
+fi
+if test $commandcompleted -eq 0 -a -n "$qemu_pid"
+then
+	if ! test -f "$resdir/../STOP.1"
+	then
+		echo Grace period for qemu job at pid $qemu_pid
+	fi
+	oldline="`tail $resdir/console.log`"
+	while :
+	do
+		if test -f "$resdir/../STOP.1"
+		then
+			echo "PID $qemu_pid killed due to run STOP.1 request" >> $resdir/Warnings 2>&1
+			kill -KILL $qemu_pid
+			break
+		fi
+		kruntime=`gawk 'BEGIN { print systime() - '"$kstarttime"' }' < /dev/null`
+		if kill -0 $qemu_pid > /dev/null 2>&1
+		then
+			:
+		else
+			break
+		fi
+		must_continue=no
+		newline="`tail $resdir/console.log`"
+		if test "$newline" != "$oldline" && echo $newline | grep -q ' [0-9]\+us : '
+		then
+			must_continue=yes
+		fi
+		last_ts="`tail $resdir/console.log | grep '^\[ *[0-9]\+\.[0-9]\+]' | tail -1 | sed -e 's/^\[ *//' -e 's/\..*$//'`"
+		if test -z "$last_ts"
+		then
+			last_ts=0
+		fi
+		if test "$newline" != "$oldline" -a "$last_ts" -lt $((seconds + $TORTURE_SHUTDOWN_GRACE))
+		then
+			must_continue=yes
+		fi
+		if test $must_continue = no -a $kruntime -ge $((seconds + $TORTURE_SHUTDOWN_GRACE))
+		then
+			echo "!!! PID $qemu_pid hung at $kruntime vs. $seconds seconds" >> $resdir/Warnings 2>&1
+			kill -KILL $qemu_pid
+			break
+		fi
+		oldline=$newline
+		sleep 10
+	done
+elif test -z "$qemu_pid"
+then
+	echo Unknown PID, cannot kill qemu command
+fi
+
+# Tell the script that this run is done.
+rm -f $resdir/build.run
+
+parse-console.sh $resdir/console.log $title
diff --git a/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh b/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh
index 536d103ef166..420ed5ce9d32 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh
@@ -7,15 +7,15 @@
 # Execute this in the source tree.  Do not run it as a background task
 # because qemu does not seem to like that much.
 #
-# Usage: kvm-test-1-run.sh config builddir resdir seconds qemu-args boot_args
+# Usage: kvm-test-1-run.sh config resdir seconds qemu-args boot_args_in
 #
 # qemu-args defaults to "-enable-kvm -nographic", along with arguments
 #			specifying the number of CPUs and other options
 #			generated from the underlying CPU architecture.
-# boot_args defaults to value returned by the per_version_boot_params
+# boot_args_in defaults to value returned by the per_version_boot_params
 #			shell function.
 #
-# Anything you specify for either qemu-args or boot_args is appended to
+# Anything you specify for either qemu-args or boot_args_in is appended to
 # the default values.  The "-smp" value is deduced from the contents of
 # the config fragment.
 #
@@ -35,14 +35,13 @@ mkdir $T
 config_template=${1}
 config_dir=`echo $config_template | sed -e 's,/[^/]*$,,'`
 title=`echo $config_template | sed -e 's/^.*\///'`
-builddir=${2}
-resdir=${3}
+resdir=${2}
 if test -z "$resdir" -o ! -d "$resdir" -o ! -w "$resdir"
 then
 	echo "kvm-test-1-run.sh :$resdir: Not a writable directory, cannot store results into it"
 	exit 1
 fi
-echo ' ---' `date`: Starting build
+echo ' ---' `date`: Starting build, PID $$
 echo ' ---' Kconfig fragment at: $config_template >> $resdir/log
 touch $resdir/ConfigFragment.input
 
@@ -73,7 +72,7 @@ config_override_param "--kconfig argument" KcList "$TORTURE_KCONFIG_ARG"
 cp $T/KcList $resdir/ConfigFragment
 
 base_resdir=`echo $resdir | sed -e 's/\.[0-9]\+$//'`
-if test "$base_resdir" != "$resdir" -a -f $base_resdir/bzImage -a -f $base_resdir/vmlinux
+if test "$base_resdir" != "$resdir" && test -f $base_resdir/bzImage && test -f $base_resdir/vmlinux
 then
 	# Rerunning previous test, so use that test's kernel.
 	QEMU="`identify_qemu $base_resdir/vmlinux`"
@@ -83,6 +82,17 @@ then
 	ln -s $base_resdir/.config $resdir  # for kvm-recheck.sh
 	# Arch-independent indicator
 	touch $resdir/builtkernel
+elif test "$base_resdir" != "$resdir"
+then
+	# Rerunning previous test for which build failed
+	ln -s $base_resdir/Make*.out $resdir  # for kvm-recheck.sh
+	ln -s $base_resdir/.config $resdir  # for kvm-recheck.sh
+	echo Initial build failed, not running KVM, see $resdir.
+	if test -f $resdir/build.wait
+	then
+		mv $resdir/build.wait $resdir/build.ready
+	fi
+	exit 1
 elif kvm-build.sh $T/KcList $resdir
 then
 	# Had to build a kernel for this test.
@@ -107,23 +117,23 @@ else
 	# Build failed.
 	cp .config $resdir || :
 	echo Build failed, not running KVM, see $resdir.
-	if test -f $builddir.wait
+	if test -f $resdir/build.wait
 	then
-		mv $builddir.wait $builddir.ready
+		mv $resdir/build.wait $resdir/build.ready
 	fi
 	exit 1
 fi
-if test -f $builddir.wait
+if test -f $resdir/build.wait
 then
-	mv $builddir.wait $builddir.ready
+	mv $resdir/build.wait $resdir/build.ready
 fi
-while test -f $builddir.ready
+while test -f $resdir/build.ready
 do
 	sleep 1
 done
-seconds=$4
-qemu_args=$5
-boot_args=$6
+seconds=$3
+qemu_args=$4
+boot_args_in=$5
 
 if test -z "$TORTURE_BUILDONLY"
 then
@@ -133,7 +143,7 @@ fi
 # Generate -smp qemu argument.
 qemu_args="-enable-kvm -nographic $qemu_args"
 cpu_count=`configNR_CPUS.sh $resdir/ConfigFragment`
-cpu_count=`configfrag_boot_cpus "$boot_args" "$config_template" "$cpu_count"`
+cpu_count=`configfrag_boot_cpus "$boot_args_in" "$config_template" "$cpu_count"`
 if test "$cpu_count" -gt "$TORTURE_ALLOTED_CPUS"
 then
 	echo CPU count limited from $cpu_count to $TORTURE_ALLOTED_CPUS | tee -a $resdir/Warnings
@@ -149,16 +159,52 @@ qemu_args="$qemu_args `identify_qemu_args "$QEMU" "$resdir/console.log"`"
 qemu_append="`identify_qemu_append "$QEMU"`"
 
 # Pull in Kconfig-fragment boot parameters
-boot_args="`configfrag_boot_params "$boot_args" "$config_template"`"
+boot_args="`configfrag_boot_params "$boot_args_in" "$config_template"`"
 # Generate kernel-version-specific boot parameters
 boot_args="`per_version_boot_params "$boot_args" $resdir/.config $seconds`"
 if test -n "$TORTURE_BOOT_GDB_ARG"
 then
 	boot_args="$boot_args $TORTURE_BOOT_GDB_ARG"
 fi
+
+# Give bare-metal advice
+modprobe_args="`echo $boot_args | tr -s ' ' '\012' | grep "^$TORTURE_MOD\." | sed -e "s/$TORTURE_MOD\.//g"`"
+kboot_args="`echo $boot_args | tr -s ' ' '\012' | grep -v "^$TORTURE_MOD\."`"
+testid_txt="`dirname $resdir`/testid.txt"
+touch $resdir/bare-metal
+echo To run this scenario on bare metal: >> $resdir/bare-metal
+echo >> $resdir/bare-metal
+echo " 1." Set your bare-metal build tree to the state shown in this file: >> $resdir/bare-metal
+echo "   " $testid_txt >> $resdir/bare-metal
+echo " 2." Update your bare-metal build tree"'"s .config based on this file: >> $resdir/bare-metal
+echo "   " $resdir/ConfigFragment >> $resdir/bare-metal
+echo " 3." Make the bare-metal kernel"'"s build system aware of your .config updates: >> $resdir/bare-metal
+echo "   " $ 'yes "" | make oldconfig' >> $resdir/bare-metal
+echo " 4." Build your bare-metal kernel. >> $resdir/bare-metal
+echo " 5." Boot your bare-metal kernel with the following parameters: >> $resdir/bare-metal
+echo "   " $kboot_args >> $resdir/bare-metal
+echo " 6." Start the test with the following command: >> $resdir/bare-metal
+echo "   " $ modprobe $TORTURE_MOD $modprobe_args >> $resdir/bare-metal
+echo " 7." After some time, end the test with the following command: >> $resdir/bare-metal
+echo "   " $ rmmod $TORTURE_MOD >> $resdir/bare-metal
+echo " 8." Copy your bare-metal kernel"'"s .config file, overwriting this file: >> $resdir/bare-metal
+echo "   " $resdir/.config >> $resdir/bare-metal
+echo " 9." Copy the console output from just before the modprobe to just after >> $resdir/bare-metal
+echo "   " the rmmod into this file: >> $resdir/bare-metal
+echo "   " $resdir/console.log >> $resdir/bare-metal
+echo "10." Check for runtime errors using the following command: >> $resdir/bare-metal
+echo "   " $ tools/testing/selftests/rcutorture/bin/kvm-recheck.sh `dirname $resdir` >> $resdir/bare-metal
+echo >> $resdir/bare-metal
+echo Some of the above steps may be skipped if you build your bare-metal >> $resdir/bare-metal
+echo kernel here: `head -n 1 $testid_txt | sed -e 's/^Build directory: //'`  >> $resdir/bare-metal
+
 echo $QEMU $qemu_args -m $TORTURE_QEMU_MEM -kernel $KERNEL -append \"$qemu_append $boot_args\" $TORTURE_QEMU_GDB_ARG > $resdir/qemu-cmd
 echo "# TORTURE_SHUTDOWN_GRACE=$TORTURE_SHUTDOWN_GRACE" >> $resdir/qemu-cmd
 echo "# seconds=$seconds" >> $resdir/qemu-cmd
+echo "# TORTURE_KCONFIG_GDB_ARG=\"$TORTURE_KCONFIG_GDB_ARG\"" >> $resdir/qemu-cmd
+echo "# TORTURE_JITTER_START=\"$TORTURE_JITTER_START\"" >> $resdir/qemu-cmd
+echo "# TORTURE_JITTER_STOP=\"$TORTURE_JITTER_STOP\"" >> $resdir/qemu-cmd
+echo "# TORTURE_TRUST_MAKE=\"$TORTURE_TRUST_MAKE\"; export TORTURE_TRUST_MAKE" >> $resdir/qemu-cmd
 
 if test -n "$TORTURE_BUILDONLY"
 then
@@ -167,140 +213,4 @@ then
 	exit 0
 fi
 
-# Decorate qemu-cmd with redirection, backgrounding, and PID capture
-sed -e 's/$/ 2>\&1 \&/' < $resdir/qemu-cmd > $T/qemu-cmd
-echo 'echo $! > $resdir/qemu_pid' >> $T/qemu-cmd
-
-# In case qemu refuses to run...
-echo "NOTE: $QEMU either did not run or was interactive" > $resdir/console.log
-
-# Attempt to run qemu
-kstarttime=`gawk 'BEGIN { print systime() }' < /dev/null`
-( . $T/qemu-cmd; wait `cat  $resdir/qemu_pid`; echo $? > $resdir/qemu-retval ) &
-commandcompleted=0
-if test -z "$TORTURE_KCONFIG_GDB_ARG"
-then
-	sleep 10 # Give qemu's pid a chance to reach the file
-	if test -s "$resdir/qemu_pid"
-	then
-		qemu_pid=`cat "$resdir/qemu_pid"`
-		echo Monitoring qemu job at pid $qemu_pid
-	else
-		qemu_pid=""
-		echo Monitoring qemu job at yet-as-unknown pid
-	fi
-fi
-if test -n "$TORTURE_KCONFIG_GDB_ARG"
-then
-	echo Waiting for you to attach a debug session, for example: > /dev/tty
-	echo "    gdb $base_resdir/vmlinux" > /dev/tty
-	echo 'After symbols load and the "(gdb)" prompt appears:' > /dev/tty
-	echo "    target remote :1234" > /dev/tty
-	echo "    continue" > /dev/tty
-	kstarttime=`gawk 'BEGIN { print systime() }' < /dev/null`
-fi
-while :
-do
-	if test -z "$qemu_pid" -a -s "$resdir/qemu_pid"
-	then
-		qemu_pid=`cat "$resdir/qemu_pid"`
-	fi
-	kruntime=`gawk 'BEGIN { print systime() - '"$kstarttime"' }' < /dev/null`
-	if test -z "$qemu_pid" || kill -0 "$qemu_pid" > /dev/null 2>&1
-	then
-		if test -n "$TORTURE_KCONFIG_GDB_ARG"
-		then
-			:
-		elif test $kruntime -ge $seconds || test -f "$resdir/../STOP.1"
-		then
-			break;
-		fi
-		sleep 1
-	else
-		commandcompleted=1
-		if test $kruntime -lt $seconds
-		then
-			echo Completed in $kruntime vs. $seconds >> $resdir/Warnings 2>&1
-			grep "^(qemu) qemu:" $resdir/kvm-test-1-run.sh.out >> $resdir/Warnings 2>&1
-			killpid="`sed -n "s/^(qemu) qemu: terminating on signal [0-9]* from pid \([0-9]*\).*$/\1/p" $resdir/Warnings`"
-			if test -n "$killpid"
-			then
-				echo "ps -fp $killpid" >> $resdir/Warnings 2>&1
-				ps -fp $killpid >> $resdir/Warnings 2>&1
-			fi
-			# Reduce probability of PID reuse by allowing a one-minute buffer
-			if test $((kruntime + 60)) -lt $seconds && test -s "$resdir/../jitter_pids"
-			then
-				awk < "$resdir/../jitter_pids" '
-				NF > 0 {
-					pidlist = pidlist " " $1;
-					n++;
-				}
-				END {
-					if (n > 0) {
-						print "kill " pidlist;
-					}
-				}' | sh
-			fi
-		else
-			echo ' ---' `date`: "Kernel done"
-		fi
-		break
-	fi
-done
-if test -z "$qemu_pid" -a -s "$resdir/qemu_pid"
-then
-	qemu_pid=`cat "$resdir/qemu_pid"`
-fi
-if test $commandcompleted -eq 0 -a -n "$qemu_pid"
-then
-	if ! test -f "$resdir/../STOP.1"
-	then
-		echo Grace period for qemu job at pid $qemu_pid
-	fi
-	oldline="`tail $resdir/console.log`"
-	while :
-	do
-		if test -f "$resdir/../STOP.1"
-		then
-			echo "PID $qemu_pid killed due to run STOP.1 request" >> $resdir/Warnings 2>&1
-			kill -KILL $qemu_pid
-			break
-		fi
-		kruntime=`gawk 'BEGIN { print systime() - '"$kstarttime"' }' < /dev/null`
-		if kill -0 $qemu_pid > /dev/null 2>&1
-		then
-			:
-		else
-			break
-		fi
-		must_continue=no
-		newline="`tail $resdir/console.log`"
-		if test "$newline" != "$oldline" && echo $newline | grep -q ' [0-9]\+us : '
-		then
-			must_continue=yes
-		fi
-		last_ts="`tail $resdir/console.log | grep '^\[ *[0-9]\+\.[0-9]\+]' | tail -1 | sed -e 's/^\[ *//' -e 's/\..*$//'`"
-		if test -z "$last_ts"
-		then
-			last_ts=0
-		fi
-		if test "$newline" != "$oldline" -a "$last_ts" -lt $((seconds + $TORTURE_SHUTDOWN_GRACE))
-		then
-			must_continue=yes
-		fi
-		if test $must_continue = no -a $kruntime -ge $((seconds + $TORTURE_SHUTDOWN_GRACE))
-		then
-			echo "!!! PID $qemu_pid hung at $kruntime vs. $seconds seconds" >> $resdir/Warnings 2>&1
-			kill -KILL $qemu_pid
-			break
-		fi
-		oldline=$newline
-		sleep 10
-	done
-elif test -z "$qemu_pid"
-then
-	echo Unknown PID, cannot kill qemu command
-fi
-
-parse-console.sh $resdir/console.log $title
+kvm-test-1-run-qemu.sh $resdir
diff --git a/tools/testing/selftests/rcutorture/bin/kvm-transform.sh b/tools/testing/selftests/rcutorture/bin/kvm-transform.sh
index c45a953ef393..d40b4e60a50c 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm-transform.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm-transform.sh
@@ -3,7 +3,7 @@
 #
 # Transform a qemu-cmd file to allow reuse.
 #
-# Usage: kvm-transform.sh bzImage console.log < qemu-cmd-in > qemu-cmd-out
+# Usage: kvm-transform.sh bzImage console.log jitter_dir [ seconds ] < qemu-cmd-in > qemu-cmd-out
 #
 #	bzImage: Kernel and initrd from the same prior kvm.sh run.
 #	console.log: File into which to place console output.
@@ -29,20 +29,62 @@ then
 	echo "Need console log file name."
 	exit 1
 fi
+jitter_dir="$3"
+if test -z "$jitter_dir" || ! test -d "$jitter_dir"
+then
+	echo "Need valid jitter directory: '$jitter_dir'"
+	exit 1
+fi
+seconds="$4"
+if test -n "$seconds" && echo $seconds | grep -q '[^0-9]'
+then
+	echo "Invalid duration, should be numeric in seconds: '$seconds'"
+	exit 1
+fi
+
+awk -v image="$image" -v consolelog="$consolelog" -v jitter_dir="$jitter_dir" \
+    -v seconds="$seconds" '
+/^# seconds=/ {
+	if (seconds == "")
+		print $0;
+	else
+		print "# seconds=" seconds;
+	next;
+}
+
+/^# TORTURE_JITTER_START=/ {
+	print "# TORTURE_JITTER_START=\". jitterstart.sh " $4 " " jitter_dir " " $6 " " $7;
+	next;
+}
+
+/^# TORTURE_JITTER_STOP=/ {
+	print "# TORTURE_JITTER_STOP=\". jitterstop.sh " " " jitter_dir " " $5;
+	next;
+}
+
+/^#/ {
+	print $0;
+	next;
+}
 
-awk -v image="$image" -v consolelog="$consolelog" '
 {
 	line = "";
 	for (i = 1; i <= NF; i++) {
-		if (line == "")
+		if ("" seconds != "" && $i ~ /\.shutdown_secs=[0-9]*$/) {
+			sub(/[0-9]*$/, seconds, $i);
+			if (line == "")
+				line = $i;
+			else
+				line = line " " $i;
+		} else if (line == "") {
 			line = $i;
-		else
+		} else {
 			line = line " " $i;
+		}
 		if ($i == "-serial") {
 			i++;
 			line = line " file:" consolelog;
-		}
-		if ($i == "-kernel") {
+		} else if ($i == "-kernel") {
 			i++;
 			line = line " " image;
 		}
diff --git a/tools/testing/selftests/rcutorture/bin/kvm.sh b/tools/testing/selftests/rcutorture/bin/kvm.sh
index 8d3c99b35e06..6bf00a003d3d 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm.sh
@@ -29,17 +29,21 @@ PATH=${KVM}/bin:$PATH; export PATH
 TORTURE_ALLOTED_CPUS="`identify_qemu_vcpus`"
 TORTURE_DEFCONFIG=defconfig
 TORTURE_BOOT_IMAGE=""
+TORTURE_BUILDONLY=
 TORTURE_INITRD="$KVM/initrd"; export TORTURE_INITRD
 TORTURE_KCONFIG_ARG=""
 TORTURE_KCONFIG_GDB_ARG=""
 TORTURE_BOOT_GDB_ARG=""
 TORTURE_QEMU_GDB_ARG=""
+TORTURE_JITTER_START=""
+TORTURE_JITTER_STOP=""
 TORTURE_KCONFIG_KASAN_ARG=""
 TORTURE_KCONFIG_KCSAN_ARG=""
 TORTURE_KMAKE_ARG=""
 TORTURE_QEMU_MEM=512
 TORTURE_SHUTDOWN_GRACE=180
 TORTURE_SUITE=rcu
+TORTURE_MOD=rcutorture
 TORTURE_TRUST_MAKE=""
 resdir=""
 configs=""
@@ -100,7 +104,7 @@ do
 		TORTURE_BUILDONLY=1
 		;;
 	--configs|--config)
-		checkarg --configs "(list of config files)" "$#" "$2" '^[^/]\+$' '^--'
+		checkarg --configs "(list of config files)" "$#" "$2" '^[^/.a-z]\+$' '^--'
 		configs="$configs $2"
 		shift
 		;;
@@ -116,7 +120,7 @@ do
 		shift
 		;;
 	--datestamp)
-		checkarg --datestamp "(relative pathname)" "$#" "$2" '^[a-zA-Z0-9._-/]*$' '^--'
+		checkarg --datestamp "(relative pathname)" "$#" "$2" '^[a-zA-Z0-9._/-]*$' '^--'
 		ds=$2
 		shift
 		;;
@@ -215,6 +219,7 @@ do
 	--torture)
 		checkarg --torture "(suite name)" "$#" "$2" '^\(lock\|rcu\|rcuscale\|refscale\|scf\)$' '^--'
 		TORTURE_SUITE=$2
+		TORTURE_MOD="`echo $TORTURE_SUITE | sed -e 's/^\(lock\|rcu\|scf\)$/\1torture/'`"
 		shift
 		if test "$TORTURE_SUITE" = rcuscale || test "$TORTURE_SUITE" = refscale
 		then
@@ -381,6 +386,7 @@ TORTURE_QEMU_GDB_ARG="$TORTURE_QEMU_GDB_ARG"; export TORTURE_QEMU_GDB_ARG
 TORTURE_KCONFIG_KASAN_ARG="$TORTURE_KCONFIG_KASAN_ARG"; export TORTURE_KCONFIG_KASAN_ARG
 TORTURE_KCONFIG_KCSAN_ARG="$TORTURE_KCONFIG_KCSAN_ARG"; export TORTURE_KCONFIG_KCSAN_ARG
 TORTURE_KMAKE_ARG="$TORTURE_KMAKE_ARG"; export TORTURE_KMAKE_ARG
+TORTURE_MOD="$TORTURE_MOD"; export TORTURE_MOD
 TORTURE_QEMU_CMD="$TORTURE_QEMU_CMD"; export TORTURE_QEMU_CMD
 TORTURE_QEMU_INTERACTIVE="$TORTURE_QEMU_INTERACTIVE"; export TORTURE_QEMU_INTERACTIVE
 TORTURE_QEMU_MAC="$TORTURE_QEMU_MAC"; export TORTURE_QEMU_MAC
@@ -399,12 +405,17 @@ echo Results directory: $resdir/$ds
 echo $scriptname $args
 touch $resdir/$ds/log
 echo $scriptname $args >> $resdir/$ds/log
-echo ${TORTURE_SUITE} > $resdir/$ds/TORTURE_SUITE
-pwd > $resdir/$ds/testid.txt
+echo ${TORTURE_SUITE} > $resdir/$ds/torture_suite
+echo Build directory: `pwd` > $resdir/$ds/testid.txt
 if test -d .git
 then
+	echo Current commit: `git rev-parse HEAD` >> $resdir/$ds/testid.txt
+	echo >> $resdir/$ds/testid.txt
+	echo ' ---' Output of "'"git status"'": >> $resdir/$ds/testid.txt
 	git status >> $resdir/$ds/testid.txt
-	git rev-parse HEAD >> $resdir/$ds/testid.txt
+	echo >> $resdir/$ds/testid.txt
+	echo >> $resdir/$ds/testid.txt
+	echo ' ---' Output of "'"git diff HEAD"'": >> $resdir/$ds/testid.txt
 	git diff HEAD >> $resdir/$ds/testid.txt
 fi
 ___EOF___
@@ -434,8 +445,17 @@ function dump(first, pastlast, batchnum)
 	print "echo ----Start batch " batchnum ": `date` | tee -a " rd "log";
 	print "needqemurun="
 	jn=1
+	njitter = 0;
+	split(jitter, ja);
+	if (ja[1] == -1 && ncpus == 0)
+		njitter = 1;
+	else if (ja[1] == -1)
+		njitter = ncpus;
+	else
+		njitter = ja[1];
+	print "TORTURE_JITTER_START=\". jitterstart.sh " njitter " " rd " " dur " " ja[2] " " ja[3] "\"; export TORTURE_JITTER_START";
+	print "TORTURE_JITTER_STOP=\". jitterstop.sh " rd " \"; export TORTURE_JITTER_STOP"
 	for (j = first; j < pastlast; j++) {
-		builddir=KVM "/b" j - first + 1
 		cpusr[jn] = cpus[j];
 		if (cfrep[cf[j]] == "") {
 			cfr[jn] = cf[j];
@@ -444,15 +464,15 @@ function dump(first, pastlast, batchnum)
 			cfrep[cf[j]]++;
 			cfr[jn] = cf[j] "." cfrep[cf[j]];
 		}
+		builddir=rd cfr[jn] "/build";
 		if (cpusr[jn] > ncpus && ncpus != 0)
 			ovf = "-ovf";
 		else
 			ovf = "";
 		print "echo ", cfr[jn], cpusr[jn] ovf ": Starting build. `date` | tee -a " rd "log";
-		print "rm -f " builddir ".*";
-		print "touch " builddir ".wait";
 		print "mkdir " rd cfr[jn] " || :";
-		print "kvm-test-1-run.sh " CONFIGDIR cf[j], builddir, rd cfr[jn], dur " \"" TORTURE_QEMU_ARG "\" \"" TORTURE_BOOTARGS "\" > " rd cfr[jn]  "/kvm-test-1-run.sh.out 2>&1 &"
+		print "touch " builddir ".wait";
+		print "kvm-test-1-run.sh " CONFIGDIR cf[j], rd cfr[jn], dur " \"" TORTURE_QEMU_ARG "\" \"" TORTURE_BOOTARGS "\" > " rd cfr[jn]  "/kvm-test-1-run.sh.out 2>&1 &"
 		print "echo ", cfr[jn], cpusr[jn] ovf ": Waiting for build to complete. `date` | tee -a " rd "log";
 		print "while test -f " builddir ".wait"
 		print "do"
@@ -461,23 +481,21 @@ function dump(first, pastlast, batchnum)
 		print "echo ", cfr[jn], cpusr[jn] ovf ": Build complete. `date` | tee -a " rd "log";
 		jn++;
 	}
+	print "runfiles="
 	for (j = 1; j < jn; j++) {
-		builddir=KVM "/b" j
-		print "rm -f " builddir ".ready"
+		builddir=rd cfr[j] "/build";
+		if (TORTURE_BUILDONLY)
+			print "rm -f " builddir ".ready"
+		else
+			print "mv " builddir ".ready " builddir ".run"
+			print "runfiles=\"$runfiles " builddir ".run\""
+		fi
 		print "if test -f \"" rd cfr[j] "/builtkernel\""
 		print "then"
 		print "\techo ----", cfr[j], cpusr[j] ovf ": Kernel present. `date` | tee -a " rd "log";
 		print "\tneedqemurun=1"
 		print "fi"
 	}
-	njitter = 0;
-	split(jitter, ja);
-	if (ja[1] == -1 && ncpus == 0)
-		njitter = 1;
-	else if (ja[1] == -1)
-		njitter = ncpus;
-	else
-		njitter = ja[1];
 	if (TORTURE_BUILDONLY && njitter != 0) {
 		njitter = 0;
 		print "echo Build-only run, so suppressing jitter | tee -a " rd "log"
@@ -488,19 +506,18 @@ function dump(first, pastlast, batchnum)
 	print "if test -n \"$needqemurun\""
 	print "then"
 	print "\techo ---- Starting kernels. `date` | tee -a " rd "log";
-	print "\techo > " rd "jitter_pids"
-	for (j = 0; j < njitter; j++) {
-		print "\tjitter.sh " j " " dur " " ja[2] " " ja[3] "&"
-		print "\techo $! >> " rd "jitter_pids"
-	}
-	print "\twait"
+	print "\t$TORTURE_JITTER_START";
+	print "\twhile ls $runfiles > /dev/null 2>&1"
+	print "\tdo"
+	print "\t\t:"
+	print "\tdone"
+	print "\t$TORTURE_JITTER_STOP";
 	print "\techo ---- All kernel runs complete. `date` | tee -a " rd "log";
 	print "else"
 	print "\twait"
 	print "\techo ---- No kernel runs. `date` | tee -a " rd "log";
 	print "fi"
 	for (j = 1; j < jn; j++) {
-		builddir=KVM "/b" j
 		print "echo ----", cfr[j], cpusr[j] ovf ": Build/run results: | tee -a " rd "log";
 		print "cat " rd cfr[j]  "/kvm-test-1-run.sh.out | tee -a " rd "log";
 	}
@@ -548,6 +565,18 @@ echo 'ret=$?' >> $T/script
 echo "cat $T/kvm-recheck.sh.out | tee -a $resdir/$ds/log" >> $T/script
 echo 'exit $ret' >> $T/script
 
+# Extract the tests and their batches from the script.
+egrep 'Start batch|Starting build\.' $T/script | grep -v ">>" |
+	sed -e 's/:.*$//' -e 's/^echo //' -e 's/-ovf//' |
+	awk '
+	/^----Start/ {
+		batchno = $3;
+		next;
+	}
+	{
+		print batchno, $1, $2
+	}' > $T/batches
+
 if test "$dryrun" = script
 then
 	cat $T/script
@@ -566,21 +595,14 @@ then
 	exit 0
 elif test "$dryrun" = batches
 then
-	# Extract the tests and their batches from the script.
-	egrep 'Start batch|Starting build\.' $T/script | grep -v ">>" |
-		sed -e 's/:.*$//' -e 's/^echo //' -e 's/-ovf//' |
-		awk '
-		/^----Start/ {
-			batchno = $3;
-			next;
-		}
-		{
-			print batchno, $1, $2
-		}'
+	cat $T/batches
+	exit 0
 else
-	# Not a dryrun, so run the script.
+	# Not a dryrun.  Record the batches and the number of CPUs, then run the script.
 	bash $T/script
 	ret=$?
+	cp $T/batches $resdir/$ds/batches
+	echo '#' cpus=$cpus >> $resdir/$ds/batches
 	echo " --- Done at `date` (`get_starttime_duration $starttime`) exitcode $ret" | tee -a $resdir/$ds/log
 	exit $ret
 fi
diff --git a/tools/testing/selftests/rcutorture/bin/torture.sh b/tools/testing/selftests/rcutorture/bin/torture.sh
index ad7525b7ac29..56e2e1a42569 100755
--- a/tools/testing/selftests/rcutorture/bin/torture.sh
+++ b/tools/testing/selftests/rcutorture/bin/torture.sh
@@ -374,7 +374,7 @@ done
 if test "$do_kvfree" = "yes"
 then
 	torture_bootargs="rcuscale.kfree_rcu_test=1 rcuscale.kfree_nthreads=16 rcuscale.holdoff=20 rcuscale.kfree_loops=10000 torture.disable_onoff_at_boot"
-	torture_set "rcuscale-kvfree" tools/testing/selftests/rcutorture/bin/kvm.sh --torture rcuscale --allcpus --duration 10 --kconfig "CONFIG_NR_CPUS=$HALF_ALLOTED_CPUS" --trust-make
+	torture_set "rcuscale-kvfree" tools/testing/selftests/rcutorture/bin/kvm.sh --torture rcuscale --allcpus --duration 10 --kconfig "CONFIG_NR_CPUS=$HALF_ALLOTED_CPUS" --memory 1G --trust-make
 fi
 
 echo " --- " $scriptname $args
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/CFLIST b/tools/testing/selftests/rcutorture/configs/rcu/CFLIST
index f2b20db9e296..98b6175e5aa0 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/CFLIST
+++ b/tools/testing/selftests/rcutorture/configs/rcu/CFLIST
@@ -7,8 +7,8 @@ TREE07
 TREE09
 SRCU-N
 SRCU-P
-SRCU-t
-SRCU-u
+SRCU-T
+SRCU-U
 TINY01
 TINY02
 TASKS01
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/SRCU-t b/tools/testing/selftests/rcutorture/configs/rcu/SRCU-T
index d6557c38dfe4..d6557c38dfe4 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/SRCU-t
+++ b/tools/testing/selftests/rcutorture/configs/rcu/SRCU-T
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/SRCU-t.boot b/tools/testing/selftests/rcutorture/configs/rcu/SRCU-T.boot
index 238bfe3bd0cc..238bfe3bd0cc 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/SRCU-t.boot
+++ b/tools/testing/selftests/rcutorture/configs/rcu/SRCU-T.boot
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/SRCU-u b/tools/testing/selftests/rcutorture/configs/rcu/SRCU-U
index 6bc24e99862f..6bc24e99862f 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/SRCU-u
+++ b/tools/testing/selftests/rcutorture/configs/rcu/SRCU-U
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/SRCU-u.boot b/tools/testing/selftests/rcutorture/configs/rcu/SRCU-U.boot
index ce48c7b82673..ce48c7b82673 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/SRCU-u.boot
+++ b/tools/testing/selftests/rcutorture/configs/rcu/SRCU-U.boot
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/TREE03.boot b/tools/testing/selftests/rcutorture/configs/rcu/TREE03.boot
index 1c218944b1e9..64f864f1f361 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/TREE03.boot
+++ b/tools/testing/selftests/rcutorture/configs/rcu/TREE03.boot
@@ -4,3 +4,4 @@ rcutree.gp_init_delay=3
 rcutree.gp_cleanup_delay=3
 rcutree.kthread_prio=2
 threadirqs
+tree.use_softirq=0
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/TREE04.boot b/tools/testing/selftests/rcutorture/configs/rcu/TREE04.boot
index 5adc6756792a..a8d94caf7d2f 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/TREE04.boot
+++ b/tools/testing/selftests/rcutorture/configs/rcu/TREE04.boot
@@ -1 +1 @@
-rcutree.rcu_fanout_leaf=4 nohz_full=1-7
+rcutree.rcu_fanout_leaf=4 nohz_full=1-N
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/TREE08.boot b/tools/testing/selftests/rcutorture/configs/rcu/TREE08.boot
index 22478fd3a865..94d38445d393 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/TREE08.boot
+++ b/tools/testing/selftests/rcutorture/configs/rcu/TREE08.boot
@@ -1,3 +1,3 @@
 rcupdate.rcu_self_test=1
 rcutree.rcu_fanout_exact=1
-rcu_nocbs=0-7
+rcu_nocbs=all
diff --git a/tools/testing/selftests/rcutorture/configs/rcuscale/ver_functions.sh b/tools/testing/selftests/rcutorture/configs/rcuscale/ver_functions.sh
index 0333e9b18522..ffbe15109f0d 100644
--- a/tools/testing/selftests/rcutorture/configs/rcuscale/ver_functions.sh
+++ b/tools/testing/selftests/rcutorture/configs/rcuscale/ver_functions.sh
@@ -12,5 +12,5 @@
 # Adds per-version torture-module parameters to kernels supporting them.
 per_version_boot_params () {
 	echo $1 rcuscale.shutdown=1 \
-		rcuscale.verbose=1
+		rcuscale.verbose=0
 }
diff --git a/tools/testing/selftests/rcutorture/configs/refscale/ver_functions.sh b/tools/testing/selftests/rcutorture/configs/refscale/ver_functions.sh
index 321e82641287..f81fa2c541a6 100644
--- a/tools/testing/selftests/rcutorture/configs/refscale/ver_functions.sh
+++ b/tools/testing/selftests/rcutorture/configs/refscale/ver_functions.sh
@@ -12,5 +12,5 @@
 # Adds per-version torture-module parameters to kernels supporting them.
 per_version_boot_params () {
 	echo $1 refscale.shutdown=1 \
-		refscale.verbose=1
+		refscale.verbose=0
 }