1#!/bin/sh
 2# SPDX-License-Identifier: GPL-2.0+
 3#
 4# Extract any RCU CPU stall warnings present in specified file.
 5# Filter out clocksource lines.  Note that preceding-lines excludes the
 6# initial line of the stall warning but trailing-lines includes it.
 7#
 8# Usage: extract-stall.sh dmesg-file [ preceding-lines [ trailing-lines ] ]
 9
10echo $1
11preceding_lines="${2-3}"
12trailing_lines="${3-10}"
13
14awk -v preceding_lines="$preceding_lines" -v trailing_lines="$trailing_lines" '
15suffix <= 0 {
16	for (i = preceding_lines; i > 0; i--)
17		last[i] = last[i - 1];
18	last[0] = $0;
19}
20
21suffix > 0 {
22	print $0;
23	suffix--;
24	if (suffix <= 0)
25		print "";
26}
27
28suffix <= 0 && /detected stall/ {
29	for (i = preceding_lines; i >= 0; i--)
30		if (last[i] != "")
31			print last[i];
32	suffix = trailing_lines;
33}' < "$1" | tr -d '\015' | grep -v clocksource
34