Merge tag 'rcu.release.v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux

Pull RCU updates from Neeraj Upadhyay:
 "Context tracking:
   - rename context tracking state related symbols and remove references
     to "dynticks" in various context tracking state variables and
     related helpers
   - force context_tracking_enabled_this_cpu() to be inlined to avoid
     leaving a noinstr section

  CSD lock:
   - enhance CSD-lock diagnostic reports
   - add an API to provide an indication of ongoing CSD-lock stall

  nocb:
   - update and simplify RCU nocb code to handle (de-)offloading of
     callbacks only for offline CPUs
   - fix RT throttling hrtimer being armed from offline CPU

  rcutorture:
   - remove redundant rcu_torture_ops get_gp_completed fields
   - add SRCU ->same_gp_state and ->get_comp_state functions
   - add generic test for NUM_ACTIVE_*RCU_POLL* for testing RCU and SRCU
     polled grace periods
   - add CFcommon.arch for arch-specific Kconfig options
   - print number of update types in rcu_torture_write_types()
   - add rcutree.nohz_full_patience_delay testing to the TREE07 scenario
   - add a stall_cpu_repeat module parameter to test repeated CPU stalls
   - add argument to limit number of CPUs a guest OS can use in
     torture.sh

  rcustall:
   - abbreviate RCU CPU stall warnings during CSD-lock stalls
   - Allow dump_cpu_task() to be called without disabling preemption
   - defer printing stall-warning backtrace when holding rcu_node lock

  srcu:
   - make SRCU gp seq wrap-around faster
   - add KCSAN checks for concurrent updates to ->srcu_n_exp_nodelay and
     ->reschedule_count which are used in heuristics governing
     auto-expediting of normal SRCU grace periods and
     grace-period-state-machine delays
   - mark idle SRCU-barrier callbacks to help identify stuck
     SRCU-barrier callback

  rcu tasks:
   - remove RCU Tasks Rude asynchronous APIs as they are no longer used
   - stop testing RCU Tasks Rude asynchronous APIs
   - fix access to non-existent percpu regions
   - check processor-ID assumptions during chosen CPU calculation for
     callback enqueuing
   - update description of rtp->tasks_gp_seq grace-period sequence
     number
   - add rcu_barrier_cb_is_done() to identify whether a given
     rcu_barrier callback is stuck
   - mark idle Tasks-RCU-barrier callbacks
   - add *torture_stats_print() functions to print detailed diagnostics
     for Tasks-RCU variants
   - capture start time of rcu_barrier_tasks*() operation to help
     distinguish a hung barrier operation from a long series of barrier
     operations

  refscale:
   - add a TINY scenario to support tests of Tiny RCU and Tiny
     SRCU
   - optimize process_durations() operation

  rcuscale:
   - dump stacks of stalled rcu_scale_writer() instances and
     grace-period statistics when rcu_scale_writer() stalls
   - mark idle RCU-barrier callbacks to identify stuck RCU-barrier
     callbacks
   - print detailed grace-period and barrier diagnostics on
     rcu_scale_writer() hangs for Tasks-RCU variants
   - warn if async module parameter is specified for RCU implementations
     that do not have async primitives such as RCU Tasks Rude
   - make all writer tasks report upon hang
   - tolerate repeated GFP_KERNEL failure in rcu_scale_writer()
   - use special allocator for rcu_scale_writer()
   - NULL out top-level pointers to heap memory to avoid double-free
     bugs on modprobe failures
   - maintain per-task instead of per-CPU callbacks count to avoid any
     issues with migration of either tasks or callbacks
   - constify struct ref_scale_ops

  Fixes:
   - use system_unbound_wq for kfree_rcu work to avoid disturbing
     isolated CPUs

  Misc:
   - warn on unexpected rcu_state.srs_done_tail state
   - better define "atomic" for list_replace_rcu() and
     hlist_replace_rcu() routines
   - annotate struct kvfree_rcu_bulk_data with __counted_by()"

* tag 'rcu.release.v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux: (90 commits)
  rcu: Defer printing stall-warning backtrace when holding rcu_node lock
  rcu/nocb: Remove superfluous memory barrier after bypass enqueue
  rcu/nocb: Conditionally wake up rcuo if not already waiting on GP
  rcu/nocb: Fix RT throttling hrtimer armed from offline CPU
  rcu/nocb: Simplify (de-)offloading state machine
  context_tracking: Tag context_tracking_enabled_this_cpu() __always_inline
  context_tracking, rcu: Rename rcu_dyntick trace event into rcu_watching
  rcu: Update stray documentation references to rcu_dynticks_eqs_{enter, exit}()
  rcu: Rename rcu_momentary_dyntick_idle() into rcu_momentary_eqs()
  rcu: Rename rcu_implicit_dynticks_qs() into rcu_watching_snap_recheck()
  rcu: Rename dyntick_save_progress_counter() into rcu_watching_snap_save()
  rcu: Rename struct rcu_data .exp_dynticks_snap into .exp_watching_snap
  rcu: Rename struct rcu_data .dynticks_snap into .watching_snap
  rcu: Rename rcu_dynticks_zero_in_eqs() into rcu_watching_zero_in_eqs()
  rcu: Rename rcu_dynticks_in_eqs_since() into rcu_watching_snap_stopped_since()
  rcu: Rename rcu_dynticks_in_eqs() into rcu_watching_snap_in_eqs()
  rcu: Rename rcu_dynticks_eqs_online() into rcu_watching_online()
  context_tracking, rcu: Rename rcu_dynticks_curr_cpu_in_eqs() into rcu_is_watching_curr_cpu()
  context_tracking, rcu: Rename rcu_dynticks_task*() into rcu_task*()
  refscale: Constify struct ref_scale_ops
  ...

9 files changed, 55 insertions, 15 deletions

diff --git a/tools/rcu/rcu-updaters.sh b/tools/rcu/rcu-updaters.sh
index 4ef1397927bb..8a5df3f22550 100755
--- a/tools/rcu/rcu-updaters.sh
+++ b/tools/rcu/rcu-updaters.sh
@@ -21,12 +21,10 @@ fi
 bpftrace -e 'kprobe:kvfree_call_rcu,
 	     kprobe:call_rcu,
 	     kprobe:call_rcu_tasks,
-	     kprobe:call_rcu_tasks_rude,
 	     kprobe:call_rcu_tasks_trace,
 	     kprobe:call_srcu,
 	     kprobe:rcu_barrier,
 	     kprobe:rcu_barrier_tasks,
-	     kprobe:rcu_barrier_tasks_rude,
 	     kprobe:rcu_barrier_tasks_trace,
 	     kprobe:srcu_barrier,
 	     kprobe:synchronize_rcu,
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 b33cd8753689..ad79784e552d 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm-test-1-run.sh
@@ -68,6 +68,8 @@ config_override_param "--gdb options" KcList "$TORTURE_KCONFIG_GDB_ARG"
 config_override_param "--kasan options" KcList "$TORTURE_KCONFIG_KASAN_ARG"
 config_override_param "--kcsan options" KcList "$TORTURE_KCONFIG_KCSAN_ARG"
 config_override_param "--kconfig argument" KcList "$TORTURE_KCONFIG_ARG"
+config_override_param "$config_dir/CFcommon.$(uname -m)" KcList \
+		      "`cat $config_dir/CFcommon.$(uname -m) 2> /dev/null`"
 cp $T/KcList $resdir/ConfigFragment
 
 base_resdir=`echo $resdir | sed -e 's/\.[0-9]\+$//'`
diff --git a/tools/testing/selftests/rcutorture/bin/torture.sh b/tools/testing/selftests/rcutorture/bin/torture.sh
index 990d24696fd3..0447c4a00cc4 100755
--- a/tools/testing/selftests/rcutorture/bin/torture.sh
+++ b/tools/testing/selftests/rcutorture/bin/torture.sh
@@ -19,10 +19,10 @@ PATH=${RCUTORTURE}/bin:$PATH; export PATH
 
 TORTURE_ALLOTED_CPUS="`identify_qemu_vcpus`"
 MAKE_ALLOTED_CPUS=$((TORTURE_ALLOTED_CPUS*2))
-HALF_ALLOTED_CPUS=$((TORTURE_ALLOTED_CPUS/2))
-if test "$HALF_ALLOTED_CPUS" -lt 1
+SCALE_ALLOTED_CPUS=$((TORTURE_ALLOTED_CPUS/2))
+if test "$SCALE_ALLOTED_CPUS" -lt 1
 then
-	HALF_ALLOTED_CPUS=1
+	SCALE_ALLOTED_CPUS=1
 fi
 VERBOSE_BATCH_CPUS=$((TORTURE_ALLOTED_CPUS/16))
 if test "$VERBOSE_BATCH_CPUS" -lt 2
@@ -90,6 +90,7 @@ usage () {
 	echo "       --do-scftorture / --do-no-scftorture / --no-scftorture"
 	echo "       --do-srcu-lockdep / --do-no-srcu-lockdep / --no-srcu-lockdep"
 	echo "       --duration [ <minutes> | <hours>h | <days>d ]"
+	echo "       --guest-cpu-limit N"
 	echo "       --kcsan-kmake-arg kernel-make-arguments"
 	exit 1
 }
@@ -203,6 +204,21 @@ do
 		duration_base=$(($ts*mult))
 		shift
 		;;
+	--guest-cpu-limit|--guest-cpu-lim)
+		checkarg --guest-cpu-limit "(number)" "$#" "$2" '^[0-9]*$' '^--'
+		if (("$2" <= "$TORTURE_ALLOTED_CPUS" / 2))
+		then
+			SCALE_ALLOTED_CPUS="$2"
+			VERBOSE_BATCH_CPUS="$((SCALE_ALLOTED_CPUS/8))"
+			if (("$VERBOSE_BATCH_CPUS" < 2))
+			then
+				VERBOSE_BATCH_CPUS=0
+			fi
+		else
+			echo "Ignoring value of $2 for --guest-cpu-limit which is greater than (("$TORTURE_ALLOTED_CPUS" / 2))."
+		fi
+		shift
+		;;
 	--kcsan-kmake-arg|--kcsan-kmake-args)
 		checkarg --kcsan-kmake-arg "(kernel make arguments)" $# "$2" '.*' '^error$'
 		kcsan_kmake_args="`echo "$kcsan_kmake_args $2" | sed -e 's/^ *//' -e 's/ *$//'`"
@@ -425,9 +441,9 @@ fi
 if test "$do_scftorture" = "yes"
 then
 	# Scale memory based on the number of CPUs.
-	scfmem=$((3+HALF_ALLOTED_CPUS/16))
-	torture_bootargs="scftorture.nthreads=$HALF_ALLOTED_CPUS torture.disable_onoff_at_boot csdlock_debug=1"
-	torture_set "scftorture" tools/testing/selftests/rcutorture/bin/kvm.sh --torture scf --allcpus --duration "$duration_scftorture" --configs "$configs_scftorture" --kconfig "CONFIG_NR_CPUS=$HALF_ALLOTED_CPUS" --memory ${scfmem}G --trust-make
+	scfmem=$((3+SCALE_ALLOTED_CPUS/16))
+	torture_bootargs="scftorture.nthreads=$SCALE_ALLOTED_CPUS torture.disable_onoff_at_boot csdlock_debug=1"
+	torture_set "scftorture" tools/testing/selftests/rcutorture/bin/kvm.sh --torture scf --allcpus --duration "$duration_scftorture" --configs "$configs_scftorture" --kconfig "CONFIG_NR_CPUS=$SCALE_ALLOTED_CPUS" --memory ${scfmem}G --trust-make
 fi
 
 if test "$do_rt" = "yes"
@@ -471,8 +487,8 @@ for prim in $primlist
 do
 	if test -n "$firsttime"
 	then
-		torture_bootargs="refscale.scale_type="$prim" refscale.nreaders=$HALF_ALLOTED_CPUS refscale.loops=10000 refscale.holdoff=20 torture.disable_onoff_at_boot"
-		torture_set "refscale-$prim" tools/testing/selftests/rcutorture/bin/kvm.sh --torture refscale --allcpus --duration 5 --kconfig "CONFIG_TASKS_TRACE_RCU=y CONFIG_NR_CPUS=$HALF_ALLOTED_CPUS" --bootargs "refscale.verbose_batched=$VERBOSE_BATCH_CPUS torture.verbose_sleep_frequency=8 torture.verbose_sleep_duration=$VERBOSE_BATCH_CPUS" --trust-make
+		torture_bootargs="refscale.scale_type="$prim" refscale.nreaders=$SCALE_ALLOTED_CPUS refscale.loops=10000 refscale.holdoff=20 torture.disable_onoff_at_boot"
+		torture_set "refscale-$prim" tools/testing/selftests/rcutorture/bin/kvm.sh --torture refscale --allcpus --duration 5 --kconfig "CONFIG_TASKS_TRACE_RCU=y CONFIG_NR_CPUS=$SCALE_ALLOTED_CPUS" --bootargs "refscale.verbose_batched=$VERBOSE_BATCH_CPUS torture.verbose_sleep_frequency=8 torture.verbose_sleep_duration=$VERBOSE_BATCH_CPUS" --trust-make
 		mv $T/last-resdir-nodebug $T/first-resdir-nodebug || :
 		if test -f "$T/last-resdir-kasan"
 		then
@@ -520,8 +536,8 @@ for prim in $primlist
 do
 	if test -n "$firsttime"
 	then
-		torture_bootargs="rcuscale.scale_type="$prim" rcuscale.nwriters=$HALF_ALLOTED_CPUS rcuscale.holdoff=20 torture.disable_onoff_at_boot"
-		torture_set "rcuscale-$prim" tools/testing/selftests/rcutorture/bin/kvm.sh --torture rcuscale --allcpus --duration 5 --kconfig "CONFIG_TASKS_TRACE_RCU=y CONFIG_NR_CPUS=$HALF_ALLOTED_CPUS" --trust-make
+		torture_bootargs="rcuscale.scale_type="$prim" rcuscale.nwriters=$SCALE_ALLOTED_CPUS rcuscale.holdoff=20 torture.disable_onoff_at_boot"
+		torture_set "rcuscale-$prim" tools/testing/selftests/rcutorture/bin/kvm.sh --torture rcuscale --allcpus --duration 5 --kconfig "CONFIG_TASKS_TRACE_RCU=y CONFIG_NR_CPUS=$SCALE_ALLOTED_CPUS" --trust-make
 		mv $T/last-resdir-nodebug $T/first-resdir-nodebug || :
 		if test -f "$T/last-resdir-kasan"
 		then
@@ -559,7 +575,7 @@ do_kcsan="$do_kcsan_save"
 if test "$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 $duration_rcutorture --kconfig "CONFIG_NR_CPUS=$HALF_ALLOTED_CPUS" --memory 2G --trust-make
+	torture_set "rcuscale-kvfree" tools/testing/selftests/rcutorture/bin/kvm.sh --torture rcuscale --allcpus --duration $duration_rcutorture --kconfig "CONFIG_NR_CPUS=$SCALE_ALLOTED_CPUS" --memory 2G --trust-make
 fi
 
 if test "$do_clocksourcewd" = "yes"
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/CFcommon b/tools/testing/selftests/rcutorture/configs/rcu/CFcommon
index 0e92d85313aa..217597e84905 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/CFcommon
+++ b/tools/testing/selftests/rcutorture/configs/rcu/CFcommon
@@ -1,7 +1,5 @@
 CONFIG_RCU_TORTURE_TEST=y
 CONFIG_PRINTK_TIME=y
-CONFIG_HYPERVISOR_GUEST=y
 CONFIG_PARAVIRT=y
-CONFIG_KVM_GUEST=y
 CONFIG_KCSAN_ASSUME_PLAIN_WRITES_ATOMIC=n
 CONFIG_KCSAN_REPORT_VALUE_CHANGE_ONLY=n
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/CFcommon.i686 b/tools/testing/selftests/rcutorture/configs/rcu/CFcommon.i686
new file mode 100644
index 000000000000..d8b2f555686f
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/configs/rcu/CFcommon.i686
@@ -0,0 +1,2 @@
+CONFIG_HYPERVISOR_GUEST=y
+CONFIG_KVM_GUEST=y
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/CFcommon.ppc64le b/tools/testing/selftests/rcutorture/configs/rcu/CFcommon.ppc64le
new file mode 100644
index 000000000000..133da04247ee
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/configs/rcu/CFcommon.ppc64le
@@ -0,0 +1 @@
+CONFIG_KVM_GUEST=y
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/CFcommon.x86_64 b/tools/testing/selftests/rcutorture/configs/rcu/CFcommon.x86_64
new file mode 100644
index 000000000000..d8b2f555686f
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/configs/rcu/CFcommon.x86_64
@@ -0,0 +1,2 @@
+CONFIG_HYPERVISOR_GUEST=y
+CONFIG_KVM_GUEST=y
diff --git a/tools/testing/selftests/rcutorture/configs/rcu/TREE07.boot b/tools/testing/selftests/rcutorture/configs/rcu/TREE07.boot
index 979edbf4c820..55ce305b2a3d 100644
--- a/tools/testing/selftests/rcutorture/configs/rcu/TREE07.boot
+++ b/tools/testing/selftests/rcutorture/configs/rcu/TREE07.boot
@@ -2,3 +2,4 @@ nohz_full=2-9
 rcutorture.stall_cpu=14
 rcutorture.stall_cpu_holdoff=90
 rcutorture.fwd_progress=0
+rcutree.nohz_full_patience_delay=1000
diff --git a/tools/testing/selftests/rcutorture/configs/refscale/TINY b/tools/testing/selftests/rcutorture/configs/refscale/TINY
new file mode 100644
index 000000000000..759343980b80
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/configs/refscale/TINY
@@ -0,0 +1,20 @@
+CONFIG_SMP=n
+CONFIG_PREEMPT_NONE=y
+CONFIG_PREEMPT_VOLUNTARY=n
+CONFIG_PREEMPT=n
+CONFIG_PREEMPT_DYNAMIC=n
+#CHECK#CONFIG_PREEMPT_RCU=n
+CONFIG_HZ_PERIODIC=n
+CONFIG_NO_HZ_IDLE=y
+CONFIG_NO_HZ_FULL=n
+CONFIG_HOTPLUG_CPU=n
+CONFIG_SUSPEND=n
+CONFIG_HIBERNATION=n
+CONFIG_RCU_NOCB_CPU=n
+CONFIG_DEBUG_LOCK_ALLOC=n
+CONFIG_PROVE_LOCKING=n
+CONFIG_RCU_BOOST=n
+CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
+CONFIG_RCU_EXPERT=y
+CONFIG_KPROBES=n
+CONFIG_FTRACE=n