Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RCU updates from Ingo Molnar:
 "The main RCU changes in this cycle are:

   - Documentation updates.

   - Miscellaneous fixes.

   - Preemptible-RCU fixes, including fixing an old bug in the
     interaction of RCU priority boosting and CPU hotplug.

   - SRCU updates.

   - RCU CPU stall-warning updates.

   - RCU torture-test updates"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
  rcu: Initialize tiny RCU stall-warning timeouts at boot
  rcu: Fix RCU CPU stall detection in tiny implementation
  rcu: Add GP-kthread-starvation checks to CPU stall warnings
  rcu: Make cond_resched_rcu_qs() apply to normal RCU flavors
  rcu: Optionally run grace-period kthreads at real-time priority
  ksoftirqd: Use new cond_resched_rcu_qs() function
  ksoftirqd: Enable IRQs and call cond_resched() before poking RCU
  rcutorture: Add more diagnostics in rcu_barrier() test failure case
  torture: Flag console.log file to prevent holdovers from earlier runs
  torture: Add "-enable-kvm -soundhw pcspk" to qemu command line
  rcutorture: Handle different mpstat versions
  rcutorture: Check from beginning to end of grace period
  rcu: Remove redundant rcu_batches_completed() declaration
  rcutorture: Drop rcu_torture_completed() and friends
  rcu: Provide rcu_batches_completed_sched() for TINY_RCU
  rcutorture: Use unsigned for Reader Batch computations
  rcutorture: Make build-output parsing correctly flag RCU's warnings
  rcu: Make _batches_completed() functions return unsigned long
  rcutorture: Issue warnings on close calls due to Reader Batch blows
  documentation: Fix smp typo in memory-barriers.txt
  ...

tools/testing/selftests/rcutorture/bin/cpus2use.sh

@@ -24,7 +24,7 @@
 
 ncpus=`grep '^processor' /proc/cpuinfo | wc -l`
 idlecpus=`mpstat | tail -1 | \
-	awk -v ncpus=$ncpus '{ print ncpus * ($7 + $12) / 100 }'`
+	awk -v ncpus=$ncpus '{ print ncpus * ($7 + $NF) / 100 }'`
 awk -v ncpus=$ncpus -v idlecpus=$idlecpus < /dev/null '
 BEGIN {
 	cpus2use = idlecpus;

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

@@ -30,6 +30,7 @@ else
 	echo Unreadable results directory: $i
 	exit 1
 fi
+. tools/testing/selftests/rcutorture/bin/functions.sh
 
 configfile=`echo $i | sed -e 's/^.*\///'`
 ngps=`grep ver: $i/console.log 2> /dev/null | tail -1 | sed -e 's/^.* ver: //' -e 's/ .*$//'`
@@ -48,4 +49,21 @@ else
 		title="$title ($ngpsps per second)"
 	fi
 	echo $title
+	nclosecalls=`grep --binary-files=text 'torture: Reader Batch' $i/console.log | tail -1 | awk '{for (i=NF-8;i<=NF;i++) sum+=$i; } END {print sum}'`
+	if test -z "$nclosecalls"
+	then
+		exit 0
+	fi
+	if test "$nclosecalls" -eq 0
+	then
+		exit 0
+	fi
+	# Compute number of close calls per tenth of an hour
+	nclosecalls10=`awk -v nclosecalls=$nclosecalls -v dur=$dur 'BEGIN { print int(nclosecalls * 36000 / dur) }' < /dev/null`
+	if test $nclosecalls10 -gt 5 -a $nclosecalls -gt 1
+	then
+		print_bug $nclosecalls "Reader Batch close calls in" $(($dur/60)) minute run: $i
+	else
+		print_warning $nclosecalls "Reader Batch close calls in" $(($dur/60)) minute run: $i
+	fi
 fi

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

@@ -8,9 +8,9 @@
 #
 # Usage: kvm-test-1-run.sh config builddir resdir minutes qemu-args boot_args
 #
-# qemu-args defaults to "-nographic", along with arguments specifying the
-#			number of CPUs and other options generated from
-#			the underlying CPU architecture.
+# qemu-args defaults to "-enable-kvm -soundhw pcspk -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
 #			shell function.
 #
@@ -138,7 +138,7 @@ then
 fi
 
 # Generate -smp qemu argument.
-qemu_args="-nographic $qemu_args"
+qemu_args="-enable-kvm -soundhw pcspk -nographic $qemu_args"
 cpu_count=`configNR_CPUS.sh $config_template`
 cpu_count=`configfrag_boot_cpus "$boot_args" "$config_template" "$cpu_count"`
 vcpus=`identify_qemu_vcpus`
@@ -168,6 +168,7 @@ then
 	touch $resdir/buildonly
 	exit 0
 fi
+echo "NOTE: $QEMU either did not run or was interactive" > $builddir/console.log
 echo $QEMU $qemu_args -m 512 -kernel $resdir/bzImage -append \"$qemu_append $boot_args\" > $resdir/qemu-cmd
 ( $QEMU $qemu_args -m 512 -kernel $resdir/bzImage -append "$qemu_append $boot_args"; echo $? > $resdir/qemu-retval ) &
 qemu_pid=$!

tools/testing/selftests/rcutorture/bin/parse-build.sh

@@ -26,12 +26,15 @@
 #
 # Authors: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
 
-T=$1
+F=$1
 title=$2
+T=/tmp/parse-build.sh.$$
+trap 'rm -rf $T' 0
+mkdir $T
 
 . functions.sh
 
-if grep -q CC < $T
+if grep -q CC < $F
 then
 	:
 else
@@ -39,18 +42,21 @@ else
 	exit 1
 fi
 
-if grep -q "error:" < $T
+if grep -q "error:" < $F
 then
 	print_bug $title build errors:
-	grep "error:" < $T
+	grep "error:" < $F
 	exit 2
 fi
-exit 0
 
-if egrep -q "rcu[^/]*\.c.*warning:|rcu.*\.h.*warning:" < $T
+grep warning: < $F > $T/warnings
+grep "include/linux/*rcu*\.h:" $T/warnings > $T/hwarnings
+grep "kernel/rcu/[^/]*:" $T/warnings > $T/cwarnings
+cat $T/hwarnings $T/cwarnings > $T/rcuwarnings
+if test -s $T/rcuwarnings
 then
 	print_warning $title build errors:
-	egrep "rcu[^/]*\.c.*warning:|rcu.*\.h.*warning:" < $T
+	cat $T/rcuwarnings
 	exit 2
 fi
 exit 0

tools/testing/selftests/rcutorture/bin/parse-console.sh

@@ -36,7 +36,7 @@ if grep -Pq '\x00' < $file
 then
 	print_warning Console output contains nul bytes, old qemu still running?
 fi
-egrep 'Badness|WARNING:|Warn|BUG|===========|Call Trace:|Oops:' < $file | grep -v 'ODEBUG: ' | grep -v 'Warning: unable to open an initial console' > $T
+egrep 'Badness|WARNING:|Warn|BUG|===========|Call Trace:|Oops:|Stall ended before state dump start' < $file | grep -v 'ODEBUG: ' | grep -v 'Warning: unable to open an initial console' > $T
 if test -s $T
 then
 	print_warning Assertion failure in $file $title