xref: /linux/scripts/checkstack.pl (revision 2d972b6ac972b3d3c2e4336325745568c79a5dd3)
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 #
19 #	Usage:
20 #	objdump -d vmlinux | scripts/checkstack.pl [arch]
21 #
22 #	TODO :	Port to all architectures (one regex per arch)
23 
24 use strict;
25 
26 # check for arch
27 #
28 # $re is used for two matches:
29 # $& (whole re) matches the complete objdump line with the stack growth
30 # $1 (first bracket) matches the size of the stack growth
31 #
32 # $dre is similar, but for dynamic stack redutions:
33 # $& (whole re) matches the complete objdump line with the stack growth
34 # $1 (first bracket) matches the dynamic amount of the stack growth
35 #
36 # use anything else and feel the pain ;)
37 my (@stack, $re, $dre, $x, $xs, $funcre);
38 {
39 	my $arch = shift;
40 	if ($arch eq "") {
41 		$arch = `uname -m`;
42 		chomp($arch);
43 	}
44 
45 	$x	= "[0-9a-f]";	# hex character
46 	$xs	= "[0-9a-f ]";	# hex character or space
47 	$funcre = qr/^$x* <(.*)>:$/;
48 	if ($arch eq 'aarch64') {
49 		#ffffffc0006325cc:       a9bb7bfd        stp     x29, x30, [sp,#-80]!
50 		$re = qr/^.*stp.*sp,\#-([0-9]{1,8})\]\!/o;
51 	} elsif ($arch eq 'arm') {
52 		#c0008ffc:	e24dd064	sub	sp, sp, #100	; 0x64
53 		$re = qr/.*sub.*sp, sp, #(([0-9]{2}|[3-9])[0-9]{2})/o;
54 	} elsif ($arch =~ /^x86(_64)?$/ || $arch =~ /^i[3456]86$/) {
55 		#c0105234:       81 ec ac 05 00 00       sub    $0x5ac,%esp
56 		# or
57 		#    2f60:    48 81 ec e8 05 00 00       sub    $0x5e8,%rsp
58 		$re = qr/^.*[as][du][db]    \$(0x$x{1,8}),\%(e|r)sp$/o;
59 		$dre = qr/^.*[as][du][db]    (%.*),\%(e|r)sp$/o;
60 	} elsif ($arch eq 'ia64') {
61 		#e0000000044011fc:       01 0f fc 8c     adds r12=-384,r12
62 		$re = qr/.*adds.*r12=-(([0-9]{2}|[3-9])[0-9]{2}),r12/o;
63 	} elsif ($arch eq 'm68k') {
64 		#    2b6c:       4e56 fb70       linkw %fp,#-1168
65 		#  1df770:       defc ffe4       addaw #-28,%sp
66 		$re = qr/.*(?:linkw %fp,|addaw )#-([0-9]{1,4})(?:,%sp)?$/o;
67 	} elsif ($arch eq 'mips64') {
68 		#8800402c:       67bdfff0        daddiu  sp,sp,-16
69 		$re = qr/.*daddiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
70 	} elsif ($arch eq 'mips') {
71 		#88003254:       27bdffe0        addiu   sp,sp,-32
72 		$re = qr/.*addiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
73 	} elsif ($arch eq 'nios2') {
74 		#25a8:	defffb04 	addi	sp,sp,-20
75 		$re = qr/.*addi.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
76 	} elsif ($arch eq 'openrisc') {
77 		# c000043c:       9c 21 fe f0     l.addi r1,r1,-272
78 		$re = qr/.*l\.addi.*r1,r1,-(([0-9]{2}|[3-9])[0-9]{2})/o;
79 	} elsif ($arch eq 'parisc' || $arch eq 'parisc64') {
80 		$re = qr/.*ldo ($x{1,8})\(sp\),sp/o;
81 	} elsif ($arch eq 'ppc') {
82 		#c00029f4:       94 21 ff 30     stwu    r1,-208(r1)
83 		$re = qr/.*stwu.*r1,-($x{1,8})\(r1\)/o;
84 	} elsif ($arch eq 'ppc64') {
85 		#XXX
86 		$re = qr/.*stdu.*r1,-($x{1,8})\(r1\)/o;
87 	} elsif ($arch eq 'powerpc') {
88 		$re = qr/.*st[dw]u.*r1,-($x{1,8})\(r1\)/o;
89 	} elsif ($arch =~ /^s390x?$/) {
90 		#   11160:       a7 fb ff 60             aghi   %r15,-160
91 		# or
92 		#  100092:	 e3 f0 ff c8 ff 71	 lay	 %r15,-56(%r15)
93 		$re = qr/.*(?:lay|ag?hi).*\%r15,-(([0-9]{2}|[3-9])[0-9]{2})
94 		      (?:\(\%r15\))?$/ox;
95 	} elsif ($arch =~ /^sh64$/) {
96 		#XXX: we only check for the immediate case presently,
97 		#     though we will want to check for the movi/sub
98 		#     pair for larger users. -- PFM.
99 		#a00048e0:       d4fc40f0        addi.l  r15,-240,r15
100 		$re = qr/.*addi\.l.*r15,-(([0-9]{2}|[3-9])[0-9]{2}),r15/o;
101 	} elsif ($arch eq 'sparc' || $arch eq 'sparc64') {
102 		# f0019d10:       9d e3 bf 90     save  %sp, -112, %sp
103 		$re = qr/.*save.*%sp, -(([0-9]{2}|[3-9])[0-9]{2}), %sp/o;
104 	} else {
105 		print("wrong or unknown architecture \"$arch\"\n");
106 		exit
107 	}
108 }
109 
110 #
111 # main()
112 #
113 my ($func, $file, $lastslash);
114 
115 while (my $line = <STDIN>) {
116 	if ($line =~ m/$funcre/) {
117 		$func = $1;
118 	}
119 	elsif ($line =~ m/(.*):\s*file format/) {
120 		$file = $1;
121 		$file =~ s/\.ko//;
122 		$lastslash = rindex($file, "/");
123 		if ($lastslash != -1) {
124 			$file = substr($file, $lastslash + 1);
125 		}
126 	}
127 	elsif ($line =~ m/$re/) {
128 		my $size = $1;
129 		$size = hex($size) if ($size =~ /^0x/);
130 
131 		if ($size > 0xf0000000) {
132 			$size = - $size;
133 			$size += 0x80000000;
134 			$size += 0x80000000;
135 		}
136 		next if ($size > 0x10000000);
137 
138 		next if $line !~ m/^($xs*)/;
139 		my $addr = $1;
140 		$addr =~ s/ /0/g;
141 		$addr = "0x$addr";
142 
143 		my $intro = "$addr $func [$file]:";
144 		my $padlen = 56 - length($intro);
145 		while ($padlen > 0) {
146 			$intro .= '	';
147 			$padlen -= 8;
148 		}
149 		next if ($size < 100);
150 		push @stack, "$intro$size\n";
151 	}
152 	elsif (defined $dre && $line =~ m/$dre/) {
153 		my $size = "Dynamic ($1)";
154 
155 		next if $line !~ m/^($xs*)/;
156 		my $addr = $1;
157 		$addr =~ s/ /0/g;
158 		$addr = "0x$addr";
159 
160 		my $intro = "$addr $func [$file]:";
161 		my $padlen = 56 - length($intro);
162 		while ($padlen > 0) {
163 			$intro .= '	';
164 			$padlen -= 8;
165 		}
166 		push @stack, "$intro$size\n";
167 	}
168 }
169 
170 # Sort output by size (last field)
171 print sort { ($b =~ /:\t*(\d+)$/)[0] <=> ($a =~ /:\t*(\d+)$/)[0] } @stack;
172