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diff --git a/‎ch13/3_lockdep/lock_stats_demo.sh
+60 b/‎ch13/3_lockdep/lock_stats_demo.sh
+60
@@ -0,0 +1,60 @@
+#!/bin/bash
+# ch13/3_lockdep/lock_stats_demo.sh
+# ***************************************************************
+# This program is part of the source code released for the book
+#  "Linux Kernel Programming"
+#  (c) Author: Kaiwan N Billimoria
+#  Publisher:  Packt
+#  GitHub repository:
+#  https://github.com/PacktPublishing/Linux-Kernel-Programming
+#****************************************************************
+# Brief Description:
+# Simple script to demo some kernel locking statistics.
+# [This script was initially not in the repo; apologies!]
+name=$(basename $0)
+
+die()
+{
+echo >&2 "FATAL: $@"
+exit 1
+}
+
+clear_lock_stats() {
+  echo 0 > /proc/lock_stat
+}
+enable_lock_stats() {
+  echo 1 > /proc/sys/kernel/lock_stat
+}
+disable_lock_stats() {
+  echo 0 > /proc/sys/kernel/lock_stat
+}
+view_lock_stats() {
+  cat /proc/lock_stat
+}
+
+
+#--- 'main'
+[[ -f /boot/config-$(uname -r) ]] && { # at least on x86[_64]
+   grep -w "CONFIG_LOCK_STAT=y" /boot/config-$(uname -r) >/dev/null 2>&1
+   [[ $? -ne 0 ]] && die "${name}: you're running this on a kernel without lock stats (CONFIG_LOCK_STAT) enabled"
+}
+
+[[ $(id -u) -ne 0 ]] && die "Needs root."
+
+disable_lock_stats
+
+#--- Test case --------------------------------------------------------
+# We want to see some kernel locks and their stats.
+# So run a simple command and capture the stats.
+# Enable lock stats only now!
+clear_lock_stats
+enable_lock_stats
+cat /proc/self/cmdline
+#----------------------------------------------------------------------
+
+disable_lock_stats
+REPFILE=lockstats.txt
+view_lock_stats > ${REPFILE}
+#view_lock_stats |tee ${REPFILE}
+echo "${name}: done, see the kernel locking stats in ${REPFILE}"
+exit 0