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 subsystem changes in this cycle were:

  - Miscellaneous fixes, perhaps most notably removing obsolete code
    whose only purpose in life was to gather information for the
    now-removed RCU debugfs facility. Other notable changes include
    removing NO_HZ_FULL_ALL in favor of the nohz_full kernel boot
    parameter, minor optimizations for expedited grace periods, some
    added tracing, creating an RCU-specific workqueue using Tejun's new
    WQ_MEM_RECLAIM flag, and several cleanups to code and comments.

  - SRCU cleanups and optimizations.

  - Torture-test updates, perhaps most notably the adding of ARMv8
    support, but also including numerous cleanups and usability fixes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
  rcu: Create RCU-specific workqueues with rescuers
  torture: Provide more sensible nreader/nwriter defaults for rcuperf
  torture: Grace periods do not piggyback off of themselves
  torture: Adjust rcuperf trace processing to allow for workqueues
  torture: Default jitter off when running rcuperf
  torture: Specify qemu memory size with --memory argument
  rcutorture: Add basic ARM64 support to run scripts
  rcutorture: Update kvm.sh header comment
  rcutorture: Record which grace-period primitives are tested
  rcutorture: Re-enable testing of dynamic expediting
  rcutorture: Avoid fake-writer use of undefined primitives
  rcutorture: Abstract function and module names
  rcutorture: Replace multi-instance kzalloc() with kcalloc()
  rcu: Remove SRCU throttling
  srcu: Remove dead code in srcu_gp_end()
  srcu: Reduce scans of srcu_data in counter wrap check
  srcu: Prevent sdp->srcu_gp_seq_needed_exp counter wrap
  srcu: Abstract function name
  rcu: Make expedited RCU CPU selection avoid unnecessary stores
  rcu: Trace expedited GP delays due to transitioning CPUs
  ...

11 files changed, 44 insertions, 43 deletions

diff --git a/tools/testing/selftests/rcutorture/bin/functions.sh b/tools/testing/selftests/rcutorture/bin/functions.sh
index 07a13779eece..65f6655026f0 100644
--- a/tools/testing/selftests/rcutorture/bin/functions.sh
+++ b/tools/testing/selftests/rcutorture/bin/functions.sh
@@ -136,6 +136,9 @@ identify_boot_image () {
                 qemu-system-x86_64|qemu-system-i386)
                         echo arch/x86/boot/bzImage
                         ;;
+                qemu-system-aarch64)
+                        echo arch/arm64/boot/Image
+                        ;;
                 *)
                         echo vmlinux
                         ;;
@@ -158,6 +161,9 @@ identify_qemu () {
         elif echo $u | grep -q "Intel 80386"
         then
                 echo qemu-system-i386
+        elif echo $u | grep -q aarch64
+        then
+                echo qemu-system-aarch64
         elif uname -a | grep -q ppc64
         then
                 echo qemu-system-ppc64
@@ -176,16 +182,20 @@ identify_qemu () {
 # Output arguments for the qemu "-append" string based on CPU type
 # and the TORTURE_QEMU_INTERACTIVE environment variable.
 identify_qemu_append () {
+        local console=ttyS0
         case "$1" in
         qemu-system-x86_64|qemu-system-i386)
                 echo noapic selinux=0 initcall_debug debug
                 ;;
+        qemu-system-aarch64)
+                console=ttyAMA0
+                ;;
         esac
         if test -n "$TORTURE_QEMU_INTERACTIVE"
         then
                 echo root=/dev/sda
         else
-                echo console=ttyS0
+                echo console=$console
         fi
 }
 
@@ -197,6 +207,9 @@ identify_qemu_args () {
         case "$1" in
         qemu-system-x86_64|qemu-system-i386)
                 ;;
+        qemu-system-aarch64)
+                echo -machine virt,gic-version=host -cpu host
+                ;;
         qemu-system-ppc64)
                 echo -enable-kvm -M pseries -nodefaults
                 echo -device spapr-vscsi
@@ -254,7 +267,7 @@ specify_qemu_cpus () {
                 echo $2
         else
                 case "$1" in
-                qemu-system-x86_64|qemu-system-i386)
+                qemu-system-x86_64|qemu-system-i386|qemu-system-aarch64)
                         echo $2 -smp $3
                         ;;
                 qemu-system-ppc64)
diff --git a/tools/testing/selftests/rcutorture/bin/kvm-recheck-rcuperf-ftrace.sh b/tools/testing/selftests/rcutorture/bin/kvm-recheck-rcuperf-ftrace.sh
index 963f71289d22..8948f7926b21 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm-recheck-rcuperf-ftrace.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm-recheck-rcuperf-ftrace.sh
@@ -39,30 +39,31 @@ sed -e 's/us : / : /' |
 tr -d '\015' |
 awk '
 $8 == "start" {
-        if (starttask != "")
+        if (startseq != "")
                 nlost++;
         starttask = $1;
         starttime = $3;
         startseq = $7;
+        seqtask[startseq] = starttask;
 }
 
 $8 == "end" {
-        if (starttask == $1 && startseq == $7) {
+        if (startseq == $7) {
                 curgpdur = $3 - starttime;
                 gptimes[++n] = curgpdur;
                 gptaskcnt[starttask]++;
                 sum += curgpdur;
                 if (curgpdur > 1000)
                         print "Long GP " starttime "us to " $3 "us (" curgpdur "us)";
-                starttask = "";
+                startseq = "";
         } else {
                 # Lost a message or some such, reset.
-                starttask = "";
+                startseq = "";
                 nlost++;
         }
 }
 
-$8 == "done" {
+$8 == "done" && seqtask[$7] != $1 {
         piggybackcnt[$1]++;
 }
 
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 1b78a12740e5..5f8fbb0d7c17 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh
@@ -177,8 +177,8 @@ then
         exit 0
 fi
 echo "NOTE: $QEMU either did not run or was interactive" > $resdir/console.log
-echo $QEMU $qemu_args -m 512 -kernel $KERNEL -append \"$qemu_append $boot_args\" > $resdir/qemu-cmd
-( $QEMU $qemu_args -m 512 -kernel $KERNEL -append "$qemu_append $boot_args"& echo $! > $resdir/qemu_pid; wait `cat  $resdir/qemu_pid`; echo $? > $resdir/qemu-retval ) &
+echo $QEMU $qemu_args -m $TORTURE_QEMU_MEM -kernel $KERNEL -append \"$qemu_append $boot_args\" > $resdir/qemu-cmd
+( $QEMU $qemu_args -m $TORTURE_QEMU_MEM -kernel $KERNEL -append "$qemu_append $boot_args"& echo $! > $resdir/qemu_pid; wait `cat  $resdir/qemu_pid`; echo $? > $resdir/qemu-retval ) &
 commandcompleted=0
 sleep 10 # Give qemu's pid a chance to reach the file
 if test -s "$resdir/qemu_pid"
diff --git a/tools/testing/selftests/rcutorture/bin/kvm.sh b/tools/testing/selftests/rcutorture/bin/kvm.sh
index 7d1f607f0f76..56610dbbdf73 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm.sh
@@ -1,10 +1,8 @@
 #!/bin/bash
 #
-# Run a series of 14 tests under KVM.  These are not particularly
-# well-selected or well-tuned, but are the current set.
-#
-# Edit the definitions below to set the locations of the various directories,
-# as well as the test duration.
+# Run a series of tests under KVM.  By default, this series is specified
+# by the relevant CFLIST file, but can be overridden by the --configs
+# command-line argument.
 #
 # Usage: kvm.sh [ options ]
 #
@@ -44,6 +42,7 @@ TORTURE_BOOT_IMAGE=""
 TORTURE_INITRD="$KVM/initrd"; export TORTURE_INITRD
 TORTURE_KCONFIG_ARG=""
 TORTURE_KMAKE_ARG=""
+TORTURE_QEMU_MEM=512
 TORTURE_SHUTDOWN_GRACE=180
 TORTURE_SUITE=rcu
 resdir=""
@@ -70,6 +69,7 @@ usage () {
         echo "       --kconfig Kconfig-options"
         echo "       --kmake-arg kernel-make-arguments"
         echo "       --mac nn:nn:nn:nn:nn:nn"
+        echo "       --memory megabytes | nnnG"
         echo "       --no-initrd"
         echo "       --qemu-args qemu-arguments"
         echo "       --qemu-cmd qemu-system-..."
@@ -147,6 +147,11 @@ do
                 TORTURE_QEMU_MAC=$2
                 shift
                 ;;
+        --memory)
+                checkarg --memory "(memory size)" $# "$2" '^[0-9]\+[MG]\?$' error
+                TORTURE_QEMU_MEM=$2
+                shift
+                ;;
         --no-initrd)
                 TORTURE_INITRD=""; export TORTURE_INITRD
                 ;;
@@ -174,6 +179,12 @@ do
                 checkarg --torture "(suite name)" "$#" "$2" '^\(lock\|rcu\|rcuperf\)$' '^--'
                 TORTURE_SUITE=$2
                 shift
+                if test "$TORTURE_SUITE" = rcuperf
+                then
+                        # If you really want jitter for rcuperf, specify
+                        # it after specifying rcuperf.  (But why?)
+                        jitter=0
+                fi
                 ;;
         *)
                 echo Unknown argument $1
@@ -288,6 +299,7 @@ TORTURE_KMAKE_ARG="$TORTURE_KMAKE_ARG"; export TORTURE_KMAKE_ARG
 TORTURE_QEMU_CMD="$TORTURE_QEMU_CMD"; export TORTURE_QEMU_CMD
 TORTURE_QEMU_INTERACTIVE="$TORTURE_QEMU_INTERACTIVE"; export TORTURE_QEMU_INTERACTIVE
 TORTURE_QEMU_MAC="$TORTURE_QEMU_MAC"; export TORTURE_QEMU_MAC
+TORTURE_QEMU_MEM="$TORTURE_QEMU_MEM"; export TORTURE_QEMU_MEM
 TORTURE_SHUTDOWN_GRACE="$TORTURE_SHUTDOWN_GRACE"; export TORTURE_SHUTDOWN_GRACE
 TORTURE_SUITE="$TORTURE_SUITE"; export TORTURE_SUITE
 if ! test -e $resdir
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/TASKS03 b/tools/testing/selftests/rcutorture/configs/rcu/TASKS03
index c70c51d5ded1..28568b72a31b 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/TASKS03
+++ b/tools/testing/selftests/rcutorture/configs/rcu/TASKS03
@@ -9,5 +9,4 @@ CONFIG_PREEMPT=y
 CONFIG_HZ_PERIODIC=n
 CONFIG_NO_HZ_IDLE=n
 CONFIG_NO_HZ_FULL=y
-CONFIG_NO_HZ_FULL_ALL=y
 #CHECK#CONFIG_RCU_EXPERT=n
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/TASKS03.boot b/tools/testing/selftests/rcutorture/configs/rcu/TASKS03.boot
index cd2a188eeb6d..838297c58318 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/TASKS03.boot
+++ b/tools/testing/selftests/rcutorture/configs/rcu/TASKS03.boot
@@ -1 +1 @@
-rcutorture.torture_type=tasks
+rcutorture.torture_type=tasks nohz_full=1
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/TREE04 b/tools/testing/selftests/rcutorture/configs/rcu/TREE04
index 27d22695d64c..24c9f6012e35 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/TREE04
+++ b/tools/testing/selftests/rcutorture/configs/rcu/TREE04
@@ -7,7 +7,6 @@ CONFIG_PREEMPT=n
 CONFIG_HZ_PERIODIC=n
 CONFIG_NO_HZ_IDLE=n
 CONFIG_NO_HZ_FULL=y
-CONFIG_NO_HZ_FULL_ALL=y
 CONFIG_RCU_FAST_NO_HZ=y
 CONFIG_RCU_TRACE=y
 CONFIG_HOTPLUG_CPU=n
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/TREE04.boot b/tools/testing/selftests/rcutorture/configs/rcu/TREE04.boot
index e34c33430447..e6071bb96c7d 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/TREE04.boot
+++ b/tools/testing/selftests/rcutorture/configs/rcu/TREE04.boot
@@ -1 +1 @@
-rcutorture.torture_type=rcu_bh rcutree.rcu_fanout_leaf=4
+rcutorture.torture_type=rcu_bh rcutree.rcu_fanout_leaf=4 nohz_full=1-7
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/TREE07 b/tools/testing/selftests/rcutorture/configs/rcu/TREE07
index 0f4759f4232e..d7afb271a586 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/TREE07
+++ b/tools/testing/selftests/rcutorture/configs/rcu/TREE07
@@ -7,7 +7,6 @@ CONFIG_PREEMPT=n
 CONFIG_HZ_PERIODIC=n
 CONFIG_NO_HZ_IDLE=n
 CONFIG_NO_HZ_FULL=y
-CONFIG_NO_HZ_FULL_ALL=n
 CONFIG_RCU_FAST_NO_HZ=n
 CONFIG_RCU_TRACE=y
 CONFIG_HOTPLUG_CPU=y
diff --git a/tools/testing/selftests/rcutorture/configs/rcuperf/ver_functions.sh b/tools/testing/selftests/rcutorture/configs/rcuperf/ver_functions.sh
index b9603115d7c7..d36b8fd6f0fc 100644
--- a/tools/testing/selftests/rcutorture/configs/rcuperf/ver_functions.sh
+++ b/tools/testing/selftests/rcutorture/configs/rcuperf/ver_functions.sh
@@ -20,32 +20,10 @@
 #
 # Authors: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
 
-# rcuperf_param_nreaders bootparam-string
-#
-# Adds nreaders rcuperf module parameter if not already specified.
-rcuperf_param_nreaders () {
-        if ! echo "$1" | grep -q "rcuperf.nreaders"
-        then
-                echo rcuperf.nreaders=-1
-        fi
-}
-
-# rcuperf_param_nwriters bootparam-string
-#
-# Adds nwriters rcuperf module parameter if not already specified.
-rcuperf_param_nwriters () {
-        if ! echo "$1" | grep -q "rcuperf.nwriters"
-        then
-                echo rcuperf.nwriters=-1
-        fi
-}
-
 # per_version_boot_params bootparam-string config-file seconds
 #
 # Adds per-version torture-module parameters to kernels supporting them.
 per_version_boot_params () {
-        echo $1 `rcuperf_param_nreaders "$1"` \
-                `rcuperf_param_nwriters "$1"` \
-                rcuperf.shutdown=1 \
+        echo $1 rcuperf.shutdown=1 \
                 rcuperf.verbose=1
 }
diff --git a/tools/testing/selftests/rcutorture/doc/rcu-test-image.txt b/tools/testing/selftests/rcutorture/doc/rcu-test-image.txt
index 66efb59a1bd1..449cf579d6f9 100644
--- a/tools/testing/selftests/rcutorture/doc/rcu-test-image.txt
+++ b/tools/testing/selftests/rcutorture/doc/rcu-test-image.txt
@@ -1,4 +1,4 @@
-This document describes one way to created the rcu-test-image file
+This document describes one way to create the rcu-test-image file
 that contains the filesystem used by the guest-OS kernel.  There are
 probably much better ways of doing this, and this filesystem could no
 doubt be smaller.  It is probably also possible to simply download