Merge tag 'rcu.2022.03.13a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu

Pull RCU updates from Paul McKenney:

 - Fix idle detection (Neeraj Upadhyay) and missing access marking
   detected by KCSAN.

 - Reduce coupling between rcu_barrier() and CPU-hotplug operations, so
   that rcu_barrier() no longer needs to do cpus_read_lock(). This may
   also someday allow system boot to bring CPUs online concurrently.

 - Enable more aggressive movement to per-CPU queueing when reacting to
   excessive lock contention due to workloads placing heavy update-side
   stress on RCU tasks.

 - Improvements to RCU priority boosting, including changes from Neeraj
   Upadhyay, Zqiang, and Alison Chaiken.

 - Various fixes improving test robustness and debug information.

 - Add tests for SRCU size transitions, further compress torture.sh
   build products, and improve debug output.

 - Miscellaneous fixes.

* tag 'rcu.2022.03.13a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (49 commits)
  rcu: Replace cpumask_weight with cpumask_empty where appropriate
  rcu: Remove __read_mostly annotations from rcu_scheduler_active externs
  rcu: Uninline multi-use function: finish_rcuwait()
  rcu: Mark writes to the rcu_segcblist structure's ->flags field
  kasan: Record work creation stack trace with interrupts enabled
  rcu: Inline __call_rcu() into call_rcu()
  rcu: Add mutex for rcu boost kthread spawning and affinity setting
  rcu: Fix description of kvfree_rcu()
  MAINTAINERS:  Add Frederic and Neeraj to their RCU files
  rcutorture: Provide non-power-of-two Tasks RCU scenarios
  rcutorture: Test SRCU size transitions
  torture: Make torture.sh help message match reality
  rcu-tasks: Set ->percpu_enqueue_shift to zero upon contention
  rcu-tasks: Use order_base_2() instead of ilog2()
  rcu: Create and use an rcu_rdp_cpu_online()
  rcu: Make rcu_barrier() no longer block CPU-hotplug operations
  rcu: Rework rcu_barrier() and callback-migration logic
  rcu: Refactor rcu_barrier() empty-list handling
  rcu: Kill rnp->ofl_seq and use only rcu_state.ofl_lock for exclusion
  torture: Change KVM environment variable to RCUTORTURE
  ...

14 files changed, 76 insertions, 42 deletions

diff --git a/tools/testing/selftests/rcutorture/bin/console-badness.sh b/tools/testing/selftests/rcutorture/bin/console-badness.sh
index e6a132df6172..69f8a5958cef 100755
--- a/tools/testing/selftests/rcutorture/bin/console-badness.sh
+++ b/tools/testing/selftests/rcutorture/bin/console-badness.sh
@@ -10,7 +10,7 @@
 #
 # Authors: Paul E. McKenney <paulmck@kernel.org>
 
-egrep 'Badness|WARNING:|Warn|BUG|===========|Call Trace:|Oops:|detected stalls on CPUs/tasks:|self-detected stall on CPU|Stall ended before state dump start|\?\?\? Writer stall state|rcu_.*kthread starved for|!!!' |
+egrep 'Badness|WARNING:|Warn|BUG|===========|BUG: KCSAN:|Call Trace:|Oops:|detected stalls on CPUs/tasks:|self-detected stall on CPU|Stall ended before state dump start|\?\?\? Writer stall state|rcu_.*kthread starved for|!!!' |
 grep -v 'ODEBUG: ' |
 grep -v 'This means that this is a DEBUG kernel and it is' |
 grep -v 'Warning: unable to open an initial console' |
diff --git a/tools/testing/selftests/rcutorture/bin/kvm-again.sh b/tools/testing/selftests/rcutorture/bin/kvm-again.sh
index 5a0023d183da..0941f1ddab65 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm-again.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm-again.sh
@@ -47,8 +47,8 @@ else
 	exit 1
 fi
 
-KVM="`pwd`/tools/testing/selftests/rcutorture"; export KVM
-PATH=${KVM}/bin:$PATH; export PATH
+RCUTORTURE="`pwd`/tools/testing/selftests/rcutorture"; export RCUTORTURE
+PATH=${RCUTORTURE}/bin:$PATH; export PATH
 . functions.sh
 
 dryrun=
diff --git a/tools/testing/selftests/rcutorture/bin/kvm-check-branches.sh b/tools/testing/selftests/rcutorture/bin/kvm-check-branches.sh
index 370406bbfeed..f17000a2ccf1 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm-check-branches.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm-check-branches.sh
@@ -49,8 +49,8 @@ fi
 mkdir $resdir/$ds
 echo Results directory: $resdir/$ds
 
-KVM="`pwd`/tools/testing/selftests/rcutorture"; export KVM
-PATH=${KVM}/bin:$PATH; export PATH
+RCUTORTURE="`pwd`/tools/testing/selftests/rcutorture"; export RCUTORTURE
+PATH=${RCUTORTURE}/bin:$PATH; export PATH
 . functions.sh
 echo Using all `identify_qemu_vcpus` CPUs.
 
diff --git a/tools/testing/selftests/rcutorture/bin/kvm-end-run-stats.sh b/tools/testing/selftests/rcutorture/bin/kvm-end-run-stats.sh
index e4a00779b8c6..ee886b40a5d2 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm-end-run-stats.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm-end-run-stats.sh
@@ -22,8 +22,8 @@ T=${TMPDIR-/tmp}/kvm-end-run-stats.sh.$$
 trap 'rm -rf $T' 0
 mkdir $T
 
-KVM="`pwd`/tools/testing/selftests/rcutorture"; export KVM
-PATH=${KVM}/bin:$PATH; export PATH
+RCUTORTURE="`pwd`/tools/testing/selftests/rcutorture"; export RCUTORTURE
+PATH=${RCUTORTURE}/bin:$PATH; export PATH
 . functions.sh
 default_starttime="`get_starttime`"
 starttime="${2-default_starttime}"
diff --git a/tools/testing/selftests/rcutorture/bin/kvm-find-errors.sh b/tools/testing/selftests/rcutorture/bin/kvm-find-errors.sh
index 2e9e9e2eedb6..5f682fc892dd 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm-find-errors.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm-find-errors.sh
@@ -30,10 +30,16 @@ editor=${EDITOR-vi}
 files=
 for i in ${rundir}/*/Make.out
 do
+	scenariodir="`dirname $i`"
+	scenariobasedir="`echo ${scenariodir} | sed -e 's/\.[0-9]*$//'`"
 	if egrep -q "error:|warning:|^ld: .*undefined reference to" < $i
 	then
 		egrep "error:|warning:|^ld: .*undefined reference to" < $i > $i.diags
 		files="$files $i.diags $i"
+	elif ! test -f ${scenariobasedir}/vmlinux
+	then
+		echo No ${scenariobasedir}/vmlinux file > $i.diags
+		files="$files $i.diags $i"
 	fi
 done
 if test -n "$files"
diff --git a/tools/testing/selftests/rcutorture/bin/kvm-recheck-rcu.sh b/tools/testing/selftests/rcutorture/bin/kvm-recheck-rcu.sh
index 1c4c2c727dad..43e1387234d1 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm-recheck-rcu.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm-recheck-rcu.sh
@@ -25,7 +25,7 @@ stopstate="`grep 'End-test grace-period state: g' $i/console.log 2> /dev/null |
 	    tail -1 | sed -e 's/^\[[ 0-9.]*] //' |
 	    awk '{ print \"[\" $1 \" \" $5 \" \" $6 \" \" $7 \"]\"; }' |
 	    tr -d '\012\015'`"
-fwdprog="`grep 'rcu_torture_fwd_prog n_max_cbs: ' $i/console.log 2> /dev/null | sed -e 's/^\[[^]]*] //' | sort -k3nr | head -1 | awk '{ print $2 " " $3 }'`"
+fwdprog="`grep 'rcu_torture_fwd_prog n_max_cbs: ' $i/console.log 2> /dev/null | sed -e 's/^\[[^]]*] //' | sort -k3nr | head -1 | awk '{ print $2 " " $3 }' | tr -d '\015'`"
 if test -z "$ngps"
 then
 	echo "$configfile ------- " $stopstate
diff --git a/tools/testing/selftests/rcutorture/bin/kvm-remote.sh b/tools/testing/selftests/rcutorture/bin/kvm-remote.sh
index e09b1bc78708..8c4c1e4792d0 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm-remote.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm-remote.sh
@@ -19,8 +19,8 @@ then
 	exit 1
 fi
 
-KVM="`pwd`/tools/testing/selftests/rcutorture"; export KVM
-PATH=${KVM}/bin:$PATH; export PATH
+RCUTORTURE="`pwd`/tools/testing/selftests/rcutorture"; export RCUTORTURE
+PATH=${RCUTORTURE}/bin:$PATH; export PATH
 . functions.sh
 
 starttime="`get_starttime`"
@@ -108,8 +108,8 @@ else
 		cat $T/kvm-again.sh.out | tee -a "$oldrun/remote-log"
 		exit 2
 	fi
-	cp -a "$rundir" "$KVM/res/"
-	oldrun="$KVM/res/$ds"
+	cp -a "$rundir" "$RCUTORTURE/res/"
+	oldrun="$RCUTORTURE/res/$ds"
 fi
 echo | tee -a "$oldrun/remote-log"
 echo " ----" kvm-again.sh output: "(`date`)" | tee -a "$oldrun/remote-log"
@@ -155,18 +155,23 @@ do
 	echo Downloading tarball to $i `date` | tee -a "$oldrun/remote-log"
 	cat $T/binres.tgz | ssh $i "cd /tmp; tar -xzf -"
 	ret=$?
-	if test "$ret" -ne 0
-	then
-		echo Unable to download $T/binres.tgz to system $i, waiting and then retrying. | tee -a "$oldrun/remote-log"
+	tries=0
+	while test "$ret" -ne 0
+	do
+		echo Unable to download $T/binres.tgz to system $i, waiting and then retrying.  $tries prior retries. | tee -a "$oldrun/remote-log"
 		sleep 60
 		cat $T/binres.tgz | ssh $i "cd /tmp; tar -xzf -"
 		ret=$?
 		if test "$ret" -ne 0
 		then
-			echo Unable to download $T/binres.tgz to system $i, giving up. | tee -a "$oldrun/remote-log"
-			exit 10
+			if test "$tries" > 5
+			then
+				echo Unable to download $T/binres.tgz to system $i, giving up. | tee -a "$oldrun/remote-log"
+				exit 10
+			fi
 		fi
-	fi
+		tries=$((tries+1))
+	done
 done
 
 # Function to check for presence of a file on the specified system.
diff --git a/tools/testing/selftests/rcutorture/bin/kvm.sh b/tools/testing/selftests/rcutorture/bin/kvm.sh
index 6de0c183db5b..55b2c1533282 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm.sh
@@ -25,15 +25,15 @@ LANG=en_US.UTF-8; export LANG
 
 dur=$((30*60))
 dryrun=""
-KVM="`pwd`/tools/testing/selftests/rcutorture"; export KVM
-PATH=${KVM}/bin:$PATH; export PATH
+RCUTORTURE="`pwd`/tools/testing/selftests/rcutorture"; export RCUTORTURE
+PATH=${RCUTORTURE}/bin:$PATH; export PATH
 . functions.sh
 
 TORTURE_ALLOTED_CPUS="`identify_qemu_vcpus`"
 TORTURE_DEFCONFIG=defconfig
 TORTURE_BOOT_IMAGE=""
 TORTURE_BUILDONLY=
-TORTURE_INITRD="$KVM/initrd"; export TORTURE_INITRD
+TORTURE_INITRD="$RCUTORTURE/initrd"; export TORTURE_INITRD
 TORTURE_KCONFIG_ARG=""
 TORTURE_KCONFIG_GDB_ARG=""
 TORTURE_BOOT_GDB_ARG=""
@@ -262,7 +262,7 @@ else
 	exit 1
 fi
 
-CONFIGFRAG=${KVM}/configs/${TORTURE_SUITE}; export CONFIGFRAG
+CONFIGFRAG=${RCUTORTURE}/configs/${TORTURE_SUITE}; export CONFIGFRAG
 
 defaultconfigs="`tr '\012' ' ' < $CONFIGFRAG/CFLIST`"
 if test -z "$configs"
@@ -272,7 +272,7 @@ fi
 
 if test -z "$resdir"
 then
-	resdir=$KVM/res
+	resdir=$RCUTORTURE/res
 fi
 
 # Create a file of test-name/#cpus pairs, sorted by decreasing #cpus.
@@ -280,7 +280,7 @@ configs_derep=
 for CF in $configs
 do
 	case $CF in
-	[0-9]\**|[0-9][0-9]\**|[0-9][0-9][0-9]\**)
+	[0-9]\**|[0-9][0-9]\**|[0-9][0-9][0-9]\**|[0-9][0-9][0-9][0-9]\**)
 		config_reps=`echo $CF | sed -e 's/\*.*$//'`
 		CF1=`echo $CF | sed -e 's/^[^*]*\*//'`
 		;;
@@ -386,7 +386,7 @@ END {
 # Generate a script to execute the tests in appropriate batches.
 cat << ___EOF___ > $T/script
 CONFIGFRAG="$CONFIGFRAG"; export CONFIGFRAG
-KVM="$KVM"; export KVM
+RCUTORTURE="$RCUTORTURE"; export RCUTORTURE
 PATH="$PATH"; export PATH
 TORTURE_ALLOTED_CPUS="$TORTURE_ALLOTED_CPUS"; export TORTURE_ALLOTED_CPUS
 TORTURE_BOOT_IMAGE="$TORTURE_BOOT_IMAGE"; export TORTURE_BOOT_IMAGE
@@ -569,7 +569,7 @@ ___EOF___
 awk < $T/cfgcpu.pack \
 	-v TORTURE_BUILDONLY="$TORTURE_BUILDONLY" \
 	-v CONFIGDIR="$CONFIGFRAG/" \
-	-v KVM="$KVM" \
+	-v RCUTORTURE="$RCUTORTURE" \
 	-v ncpus=$cpus \
 	-v jitter="$jitter" \
 	-v rd=$resdir/$ds/ \
diff --git a/tools/testing/selftests/rcutorture/bin/parse-console.sh b/tools/testing/selftests/rcutorture/bin/parse-console.sh
index 9f624bd53c27..822eb037a057 100755
--- a/tools/testing/selftests/rcutorture/bin/parse-console.sh
+++ b/tools/testing/selftests/rcutorture/bin/parse-console.sh
@@ -138,6 +138,16 @@ then
 	then
 		summary="$summary  Bugs: $n_bugs"
 	fi
+	n_kcsan=`egrep -c 'BUG: KCSAN: ' $file`
+	if test "$n_kcsan" -ne 0
+	then
+		if test "$n_bugs" = "$n_kcsan"
+		then
+			summary="$summary (all bugs kcsan)"
+		else
+			summary="$summary  KCSAN: $n_kcsan"
+		fi
+	fi
 	n_calltrace=`grep -c 'Call Trace:' $file`
 	if test "$n_calltrace" -ne 0
 	then
diff --git a/tools/testing/selftests/rcutorture/bin/torture.sh b/tools/testing/selftests/rcutorture/bin/torture.sh
index eae88aacca2a..bfe09e2829c8 100755
--- a/tools/testing/selftests/rcutorture/bin/torture.sh
+++ b/tools/testing/selftests/rcutorture/bin/torture.sh
@@ -13,8 +13,8 @@
 scriptname=$0
 args="$*"
 
-KVM="`pwd`/tools/testing/selftests/rcutorture"; export KVM
-PATH=${KVM}/bin:$PATH; export PATH
+RCUTORTURE="`pwd`/tools/testing/selftests/rcutorture"; export RCUTORTURE
+PATH=${RCUTORTURE}/bin:$PATH; export PATH
 . functions.sh
 
 TORTURE_ALLOTED_CPUS="`identify_qemu_vcpus`"
@@ -37,7 +37,7 @@ configs_scftorture=
 kcsan_kmake_args=
 
 # Default compression, duration, and apportionment.
-compress_kasan_vmlinux="`identify_qemu_vcpus`"
+compress_concurrency="`identify_qemu_vcpus`"
 duration_base=10
 duration_rcutorture_frac=7
 duration_locktorture_frac=1
@@ -67,12 +67,12 @@ function doyesno () {
 
 usage () {
 	echo "Usage: $scriptname optional arguments:"
-	echo "       --compress-kasan-vmlinux concurrency"
+	echo "       --compress-concurrency concurrency"
 	echo "       --configs-rcutorture \"config-file list w/ repeat factor (3*TINY01)\""
 	echo "       --configs-locktorture \"config-file list w/ repeat factor (10*LOCK01)\""
 	echo "       --configs-scftorture \"config-file list w/ repeat factor (2*CFLIST)\""
-	echo "       --doall"
-	echo "       --doallmodconfig / --do-no-allmodconfig"
+	echo "       --do-all"
+	echo "       --do-allmodconfig / --do-no-allmodconfig"
 	echo "       --do-clocksourcewd / --do-no-clocksourcewd"
 	echo "       --do-kasan / --do-no-kasan"
 	echo "       --do-kcsan / --do-no-kcsan"
@@ -91,9 +91,9 @@ usage () {
 while test $# -gt 0
 do
 	case "$1" in
-	--compress-kasan-vmlinux)
-		checkarg --compress-kasan-vmlinux "(concurrency level)" $# "$2" '^[0-9][0-9]*$' '^error'
-		compress_kasan_vmlinux=$2
+	--compress-concurrency)
+		checkarg --compress-concurrency "(concurrency level)" $# "$2" '^[0-9][0-9]*$' '^error'
+		compress_concurrency=$2
 		shift
 		;;
 	--config-rcutorture|--configs-rcutorture)
@@ -414,8 +414,14 @@ nfailures=0
 echo FAILURES: | tee -a $T/log
 if test -s "$T/failures"
 then
-	cat "$T/failures" | tee -a $T/log
+	awk < "$T/failures" -v sq="'" '{ print "echo " sq $0 sq; print "sed -e " sq "1,/^ --- .* Test summary:$/d" sq " " $2 "/log | grep Summary: | sed -e " sq "s/^[^S]*/  /" sq; }' | sh | tee -a $T/log | tee "$T/failuresum"
 	nfailures="`wc -l "$T/failures" | awk '{ print $1 }'`"
+	grep "^  Summary: " "$T/failuresum" |
+		grep -v '^  Summary: Bugs: [0-9]* (all bugs kcsan)$' > "$T/nonkcsan"
+	if test -s "$T/nonkcsan"
+	then
+		nonkcsanbug="yes"
+	fi
 	ret=2
 fi
 if test "$do_kcsan" = "yes"
@@ -424,12 +430,16 @@ then
 fi
 echo Started at $startdate, ended at `date`, duration `get_starttime_duration $starttime`. | tee -a $T/log
 echo Summary: Successes: $nsuccesses Failures: $nfailures. | tee -a $T/log
+if test -z "$nonkcsanbug" && test -s "$T/failuresum"
+then
+	echo "  All bugs were KCSAN failures."
+fi
 tdir="`cat $T/successes $T/failures | head -1 | awk '{ print $NF }' | sed -e 's,/[^/]\+/*$,,'`"
-if test -n "$tdir" && test $compress_kasan_vmlinux -gt 0
+if test -n "$tdir" && test $compress_concurrency -gt 0
 then
 	# KASAN vmlinux files can approach 1GB in size, so compress them.
-	echo Looking for KASAN files to compress: `date` > "$tdir/log-xz" 2>&1
-	find "$tdir" -type d -name '*-kasan' -print > $T/xz-todo
+	echo Looking for K[AC]SAN files to compress: `date` > "$tdir/log-xz" 2>&1
+	find "$tdir" -type d -name '*-k[ac]san' -print > $T/xz-todo
 	ncompresses=0
 	batchno=1
 	if test -s $T/xz-todo
@@ -447,7 +457,7 @@ then
 			do
 				xz "$j" >> "$tdir/log-xz" 2>&1 &
 				ncompresses=$((ncompresses+1))
-				if test $ncompresses -ge $compress_kasan_vmlinux
+				if test $ncompresses -ge $compress_concurrency
 				then
 					echo Waiting for batch $batchno of $ncompresses compressions `date` | tee -a "$tdir/log-xz" | tee -a $T/log
 					wait
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/RUDE01 b/tools/testing/selftests/rcutorture/configs/rcu/RUDE01
index 3ca112444ce7..7093422050f6 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/RUDE01
+++ b/tools/testing/selftests/rcutorture/configs/rcu/RUDE01
@@ -1,5 +1,5 @@
 CONFIG_SMP=y
-CONFIG_NR_CPUS=4
+CONFIG_NR_CPUS=3
 CONFIG_HOTPLUG_CPU=y
 CONFIG_PREEMPT_NONE=n
 CONFIG_PREEMPT_VOLUNTARY=n
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/SRCU-N.boot b/tools/testing/selftests/rcutorture/configs/rcu/SRCU-N.boot
index 238bfe3bd0cc..ce0694fd9b92 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/SRCU-N.boot
+++ b/tools/testing/selftests/rcutorture/configs/rcu/SRCU-N.boot
@@ -1 +1,2 @@
 rcutorture.torture_type=srcu
+rcutorture.fwd_progress=3
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/SRCU-P.boot b/tools/testing/selftests/rcutorture/configs/rcu/SRCU-P.boot
index ce48c7b82673..2db39f298d18 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/SRCU-P.boot
+++ b/tools/testing/selftests/rcutorture/configs/rcu/SRCU-P.boot
@@ -1,2 +1,4 @@
 rcutorture.torture_type=srcud
 rcupdate.rcu_self_test=1
+rcutorture.fwd_progress=3
+srcutree.big_cpu_lim=5
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/TRACE01 b/tools/testing/selftests/rcutorture/configs/rcu/TRACE01
index 34c8ff5a12f2..e4d74e5fc1d0 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/TRACE01
+++ b/tools/testing/selftests/rcutorture/configs/rcu/TRACE01
@@ -1,5 +1,5 @@
 CONFIG_SMP=y
-CONFIG_NR_CPUS=4
+CONFIG_NR_CPUS=5
 CONFIG_HOTPLUG_CPU=y
 CONFIG_PREEMPT_NONE=y
 CONFIG_PREEMPT_VOLUNTARY=n