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-rwxr-xr-xtools/rcu/extract-stall.sh48
-rw-r--r--tools/rcu/rcu-cbs.py46
2 files changed, 94 insertions, 0 deletions
diff --git a/tools/rcu/extract-stall.sh b/tools/rcu/extract-stall.sh
new file mode 100755
index 0000000000..08a39ad443
--- /dev/null
+++ b/tools/rcu/extract-stall.sh
@@ -0,0 +1,48 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0+
+
+usage() {
+ echo Extract any RCU CPU stall warnings present in specified file.
+ echo Filter out clocksource lines. Note that preceding-lines excludes the
+ echo initial line of the stall warning but trailing-lines includes it.
+ echo
+ echo Usage: $(basename $0) dmesg-file [ preceding-lines [ trailing-lines ] ]
+ echo
+ echo Error: $1
+}
+
+# Terminate the script, if the argument is missing
+
+if test -f "$1" && test -r "$1"
+then
+ :
+else
+ usage "Console log file \"$1\" missing or unreadable."
+ exit 1
+fi
+
+echo $1
+preceding_lines="${2-3}"
+trailing_lines="${3-10}"
+
+awk -v preceding_lines="$preceding_lines" -v trailing_lines="$trailing_lines" '
+suffix <= 0 {
+ for (i = preceding_lines; i > 0; i--)
+ last[i] = last[i - 1];
+ last[0] = $0;
+}
+
+suffix > 0 {
+ print $0;
+ suffix--;
+ if (suffix <= 0)
+ print "";
+}
+
+suffix <= 0 && /detected stall/ {
+ for (i = preceding_lines; i >= 0; i--)
+ if (last[i] != "")
+ print last[i];
+ suffix = trailing_lines;
+}' < "$1" | tr -d '\015' | grep -v clocksource
+
diff --git a/tools/rcu/rcu-cbs.py b/tools/rcu/rcu-cbs.py
new file mode 100644
index 0000000000..f8b461b9ea
--- /dev/null
+++ b/tools/rcu/rcu-cbs.py
@@ -0,0 +1,46 @@
+#!/usr/bin/env drgn
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Dump out the number of RCU callbacks outstanding.
+#
+# On older kernels having multiple flavors of RCU, this dumps out the
+# number of callbacks for the most heavily used flavor.
+#
+# Usage: sudo drgn rcu-cbs.py
+#
+# Copyright (C) 2021 Facebook, Inc.
+#
+# Authors: Paul E. McKenney <paulmck@kernel.org>
+
+import sys
+import drgn
+from drgn import NULL, Object
+from drgn.helpers.linux import *
+
+def get_rdp0(prog):
+ try:
+ rdp0 = prog.variable('rcu_preempt_data', 'kernel/rcu/tree.c');
+ except LookupError:
+ rdp0 = NULL;
+
+ if rdp0 == NULL:
+ try:
+ rdp0 = prog.variable('rcu_sched_data',
+ 'kernel/rcu/tree.c');
+ except LookupError:
+ rdp0 = NULL;
+
+ if rdp0 == NULL:
+ rdp0 = prog.variable('rcu_data', 'kernel/rcu/tree.c');
+ return rdp0.address_of_();
+
+rdp0 = get_rdp0(prog);
+
+# Sum up RCU callbacks.
+sum = 0;
+for cpu in for_each_possible_cpu(prog):
+ rdp = per_cpu_ptr(rdp0, cpu);
+ len = rdp.cblist.len.value_();
+ # print("CPU " + str(cpu) + " RCU callbacks: " + str(len));
+ sum += len;
+print("Number of RCU callbacks in flight: " + str(sum));