xref: /linux/scripts/checkstack.pl (revision 5c35a02c545a7bbe77f3a1ae337d9e29beed079b)
1#!/usr/bin/env perl
2# SPDX-License-Identifier: GPL-2.0
3
4#	Check the stack usage of functions
5#
6#	Copyright Joern Engel <joern@lazybastard.org>
7#	Inspired by Linus Torvalds
8#	Original idea maybe from Keith Owens
9#	s390 port and big speedup by Arnd Bergmann <arnd@bergmann-dalldorf.de>
10#	Mips port by Juan Quintela <quintela@mandrakesoft.com>
11#	IA64 port via Andreas Dilger
12#	Arm port by Holger Schurig
13#	sh64 port by Paul Mundt
14#	Random bits by Matt Mackall <mpm@selenic.com>
15#	M68k port by Geert Uytterhoeven and Andreas Schwab
16#	AArch64, PARISC ports by Kyle McMartin
17#	sparc port by Martin Habets <errandir_news@mph.eclipse.co.uk>
18#	ppc64le port by Breno Leitao <leitao@debian.org>
19#
20#	Usage:
21#	objdump -d vmlinux | scripts/checkstack.pl [arch]
22#
23#	TODO :	Port to all architectures (one regex per arch)
24
25use strict;
26
27# check for arch
28#
29# $re is used for two matches:
30# $& (whole re) matches the complete objdump line with the stack growth
31# $1 (first bracket) matches the size of the stack growth
32#
33# $dre is similar, but for dynamic stack redutions:
34# $& (whole re) matches the complete objdump line with the stack growth
35# $1 (first bracket) matches the dynamic amount of the stack growth
36#
37# use anything else and feel the pain ;)
38my (@stack, $re, $dre, $x, $xs, $funcre);
39{
40	my $arch = shift;
41	if ($arch eq "") {
42		$arch = `uname -m`;
43		chomp($arch);
44	}
45
46	$x	= "[0-9a-f]";	# hex character
47	$xs	= "[0-9a-f ]";	# hex character or space
48	$funcre = qr/^$x* <(.*)>:$/;
49	if ($arch eq 'aarch64') {
50		#ffffffc0006325cc:       a9bb7bfd        stp     x29, x30, [sp,#-80]!
51		$re = qr/^.*stp.*sp,\#-([0-9]{1,8})\]\!/o;
52	} elsif ($arch eq 'arm') {
53		#c0008ffc:	e24dd064	sub	sp, sp, #100	; 0x64
54		$re = qr/.*sub.*sp, sp, #(([0-9]{2}|[3-9])[0-9]{2})/o;
55	} elsif ($arch =~ /^x86(_64)?$/ || $arch =~ /^i[3456]86$/) {
56		#c0105234:       81 ec ac 05 00 00       sub    $0x5ac,%esp
57		# or
58		#    2f60:    48 81 ec e8 05 00 00       sub    $0x5e8,%rsp
59		$re = qr/^.*[as][du][db]    \$(0x$x{1,8}),\%(e|r)sp$/o;
60		$dre = qr/^.*[as][du][db]    (%.*),\%(e|r)sp$/o;
61	} elsif ($arch eq 'ia64') {
62		#e0000000044011fc:       01 0f fc 8c     adds r12=-384,r12
63		$re = qr/.*adds.*r12=-(([0-9]{2}|[3-9])[0-9]{2}),r12/o;
64	} elsif ($arch eq 'm68k') {
65		#    2b6c:       4e56 fb70       linkw %fp,#-1168
66		#  1df770:       defc ffe4       addaw #-28,%sp
67		$re = qr/.*(?:linkw %fp,|addaw )#-([0-9]{1,4})(?:,%sp)?$/o;
68	} elsif ($arch eq 'mips64') {
69		#8800402c:       67bdfff0        daddiu  sp,sp,-16
70		$re = qr/.*daddiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
71	} elsif ($arch eq 'mips') {
72		#88003254:       27bdffe0        addiu   sp,sp,-32
73		$re = qr/.*addiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
74	} elsif ($arch eq 'nios2') {
75		#25a8:	defffb04 	addi	sp,sp,-20
76		$re = qr/.*addi.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
77	} elsif ($arch eq 'openrisc') {
78		# c000043c:       9c 21 fe f0     l.addi r1,r1,-272
79		$re = qr/.*l\.addi.*r1,r1,-(([0-9]{2}|[3-9])[0-9]{2})/o;
80	} elsif ($arch eq 'parisc' || $arch eq 'parisc64') {
81		$re = qr/.*ldo ($x{1,8})\(sp\),sp/o;
82	} elsif ($arch eq 'powerpc' || $arch =~ /^ppc(64)?(le)?$/ ) {
83		# powerpc    : 94 21 ff 30     stwu    r1,-208(r1)
84		# ppc64(le)  : 81 ff 21 f8     stdu    r1,-128(r1)
85		$re = qr/.*st[dw]u.*r1,-($x{1,8})\(r1\)/o;
86	} elsif ($arch =~ /^s390x?$/) {
87		#   11160:       a7 fb ff 60             aghi   %r15,-160
88		# or
89		#  100092:	 e3 f0 ff c8 ff 71	 lay	 %r15,-56(%r15)
90		$re = qr/.*(?:lay|ag?hi).*\%r15,-(([0-9]{2}|[3-9])[0-9]{2})
91		      (?:\(\%r15\))?$/ox;
92	} elsif ($arch =~ /^sh64$/) {
93		#XXX: we only check for the immediate case presently,
94		#     though we will want to check for the movi/sub
95		#     pair for larger users. -- PFM.
96		#a00048e0:       d4fc40f0        addi.l  r15,-240,r15
97		$re = qr/.*addi\.l.*r15,-(([0-9]{2}|[3-9])[0-9]{2}),r15/o;
98	} elsif ($arch eq 'sparc' || $arch eq 'sparc64') {
99		# f0019d10:       9d e3 bf 90     save  %sp, -112, %sp
100		$re = qr/.*save.*%sp, -(([0-9]{2}|[3-9])[0-9]{2}), %sp/o;
101	} else {
102		print("wrong or unknown architecture \"$arch\"\n");
103		exit
104	}
105}
106
107#
108# main()
109#
110my ($func, $file, $lastslash);
111
112while (my $line = <STDIN>) {
113	if ($line =~ m/$funcre/) {
114		$func = $1;
115	}
116	elsif ($line =~ m/(.*):\s*file format/) {
117		$file = $1;
118		$file =~ s/\.ko//;
119		$lastslash = rindex($file, "/");
120		if ($lastslash != -1) {
121			$file = substr($file, $lastslash + 1);
122		}
123	}
124	elsif ($line =~ m/$re/) {
125		my $size = $1;
126		$size = hex($size) if ($size =~ /^0x/);
127
128		if ($size > 0xf0000000) {
129			$size = - $size;
130			$size += 0x80000000;
131			$size += 0x80000000;
132		}
133		next if ($size > 0x10000000);
134
135		next if $line !~ m/^($xs*)/;
136		my $addr = $1;
137		$addr =~ s/ /0/g;
138		$addr = "0x$addr";
139
140		my $intro = "$addr $func [$file]:";
141		my $padlen = 56 - length($intro);
142		while ($padlen > 0) {
143			$intro .= '	';
144			$padlen -= 8;
145		}
146		next if ($size < 100);
147		push @stack, "$intro$size\n";
148	}
149	elsif (defined $dre && $line =~ m/$dre/) {
150		my $size = "Dynamic ($1)";
151
152		next if $line !~ m/^($xs*)/;
153		my $addr = $1;
154		$addr =~ s/ /0/g;
155		$addr = "0x$addr";
156
157		my $intro = "$addr $func [$file]:";
158		my $padlen = 56 - length($intro);
159		while ($padlen > 0) {
160			$intro .= '	';
161			$padlen -= 8;
162		}
163		push @stack, "$intro$size\n";
164	}
165}
166
167# Sort output by size (last field)
168print sort { ($b =~ /:\t*(\d+)$/)[0] <=> ($a =~ /:\t*(\d+)$/)[0] } @stack;
169