xref: /linux/scripts/checkstack.pl (revision 14b42963f64b98ab61fa9723c03d71aa5ef4f862)
1#!/usr/bin/perl
2
3#	Check the stack usage of functions
4#
5#	Copyright Joern Engel <joern@wh.fh-wedel.de>
6#	Inspired by Linus Torvalds
7#	Original idea maybe from Keith Owens
8#	s390 port and big speedup by Arnd Bergmann <arnd@bergmann-dalldorf.de>
9#	Mips port by Juan Quintela <quintela@mandrakesoft.com>
10#	IA64 port via Andreas Dilger
11#	Arm port by Holger Schurig
12#	sh64 port by Paul Mundt
13#	Random bits by Matt Mackall <mpm@selenic.com>
14#	M68k port by Geert Uytterhoeven and Andreas Schwab
15#
16#	Usage:
17#	objdump -d vmlinux | stackcheck.pl [arch]
18#
19#	TODO :	Port to all architectures (one regex per arch)
20
21# check for arch
22#
23# $re is used for two matches:
24# $& (whole re) matches the complete objdump line with the stack growth
25# $1 (first bracket) matches the size of the stack growth
26#
27# use anything else and feel the pain ;)
28my (@stack, $re, $x, $xs);
29{
30	my $arch = shift;
31	if ($arch eq "") {
32		$arch = `uname -m`;
33	}
34
35	$x	= "[0-9a-f]";	# hex character
36	$xs	= "[0-9a-f ]";	# hex character or space
37	if ($arch eq 'arm') {
38		#c0008ffc:	e24dd064	sub	sp, sp, #100	; 0x64
39		$re = qr/.*sub.*sp, sp, #(([0-9]{2}|[3-9])[0-9]{2})/o;
40	} elsif ($arch =~ /^i[3456]86$/) {
41		#c0105234:       81 ec ac 05 00 00       sub    $0x5ac,%esp
42		$re = qr/^.*[as][du][db]    \$(0x$x{1,8}),\%esp$/o;
43	} elsif ($arch eq 'x86_64') {
44		#    2f60:	48 81 ec e8 05 00 00 	sub    $0x5e8,%rsp
45		$re = qr/^.*[as][du][db]    \$(0x$x{1,8}),\%rsp$/o;
46	} elsif ($arch eq 'ia64') {
47		#e0000000044011fc:       01 0f fc 8c     adds r12=-384,r12
48		$re = qr/.*adds.*r12=-(([0-9]{2}|[3-9])[0-9]{2}),r12/o;
49	} elsif ($arch eq 'm68k') {
50		#    2b6c:       4e56 fb70       linkw %fp,#-1168
51		#  1df770:       defc ffe4       addaw #-28,%sp
52		$re = qr/.*(?:linkw %fp,|addaw )#-([0-9]{1,4})(?:,%sp)?$/o;
53	} elsif ($arch eq 'mips64') {
54		#8800402c:       67bdfff0        daddiu  sp,sp,-16
55		$re = qr/.*daddiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
56	} elsif ($arch eq 'mips') {
57		#88003254:       27bdffe0        addiu   sp,sp,-32
58		$re = qr/.*addiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
59	} elsif ($arch eq 'ppc') {
60		#c00029f4:       94 21 ff 30     stwu    r1,-208(r1)
61		$re = qr/.*stwu.*r1,-($x{1,8})\(r1\)/o;
62	} elsif ($arch eq 'ppc64') {
63		#XXX
64		$re = qr/.*stdu.*r1,-($x{1,8})\(r1\)/o;
65	} elsif ($arch =~ /^s390x?$/) {
66		#   11160:       a7 fb ff 60             aghi   %r15,-160
67		$re = qr/.*ag?hi.*\%r15,-(([0-9]{2}|[3-9])[0-9]{2})/o;
68	} elsif ($arch =~ /^sh64$/) {
69		#XXX: we only check for the immediate case presently,
70		#     though we will want to check for the movi/sub
71		#     pair for larger users. -- PFM.
72		#a00048e0:       d4fc40f0        addi.l  r15,-240,r15
73		$re = qr/.*addi\.l.*r15,-(([0-9]{2}|[3-9])[0-9]{2}),r15/o;
74	} else {
75		print("wrong or unknown architecture\n");
76		exit
77	}
78}
79
80sub bysize($) {
81	my ($asize, $bsize);
82	($asize = $a) =~ s/.*:	*(.*)$/$1/;
83	($bsize = $b) =~ s/.*:	*(.*)$/$1/;
84	$bsize <=> $asize
85}
86
87#
88# main()
89#
90my $funcre = qr/^$x* <(.*)>:$/;
91my $func;
92my $file, $lastslash;
93
94while (my $line = <STDIN>) {
95	if ($line =~ m/$funcre/) {
96		$func = $1;
97	}
98	elsif ($line =~ m/(.*):\s*file format/) {
99		$file = $1;
100		$file =~ s/\.ko//;
101		$lastslash = rindex($file, "/");
102		if ($lastslash != -1) {
103			$file = substr($file, $lastslash + 1);
104		}
105	}
106	elsif ($line =~ m/$re/) {
107		my $size = $1;
108		$size = hex($size) if ($size =~ /^0x/);
109
110		if ($size > 0xf0000000) {
111			$size = - $size;
112			$size += 0x80000000;
113			$size += 0x80000000;
114		}
115		next if ($size > 0x10000000);
116
117		next if $line !~ m/^($xs*)/;
118		my $addr = $1;
119		$addr =~ s/ /0/g;
120		$addr = "0x$addr";
121
122		my $intro = "$addr $func [$file]:";
123		my $padlen = 56 - length($intro);
124		while ($padlen > 0) {
125			$intro .= '	';
126			$padlen -= 8;
127		}
128		next if ($size < 100);
129		push @stack, "$intro$size\n";
130	}
131}
132
133print sort bysize @stack;
134