scripts/checkstack.pl

   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
  25 use 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 ;)
  38 my (@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 =~ '^(aarch|arm)64$') {
  50                 #ffffffc0006325cc:       a9bb7bfd        stp     x29, x30, [sp, #-80]!
  51                 #a110:       d11643ff        sub     sp, sp, #0x590
  52                 $re = qr/^.*stp.*sp, \#-([0-9]{1,8})\]\!/o;
  53                 $dre = qr/^.*sub.*sp, sp, #(0x$x{1,8})/o;
  54         } elsif ($arch eq 'arm') {
  55                 #c0008ffc:      e24dd064        sub     sp, sp, #100    ; 0x64
  56                 $re = qr/.*sub.*sp, sp, #(([0-9]{2}|[3-9])[0-9]{2})/o;
  57         } elsif ($arch =~ /^x86(_64)?$/ || $arch =~ /^i[3456]86$/) {
  58                 #c0105234:       81 ec ac 05 00 00       sub    $0x5ac,%esp
  59                 # or
  60                 #    2f60:    48 81 ec e8 05 00 00       sub    $0x5e8,%rsp
  61                 $re = qr/^.*[as][du][db]    \$(0x$x{1,8}),\%(e|r)sp$/o;
  62                 $dre = qr/^.*[as][du][db]    (%.*),\%(e|r)sp$/o;
  63         } elsif ($arch eq 'ia64') {
  64                 #e0000000044011fc:       01 0f fc 8c     adds r12=-384,r12
  65                 $re = qr/.*adds.*r12=-(([0-9]{2}|[3-9])[0-9]{2}),r12/o;
  66         } elsif ($arch eq 'm68k') {
  67                 #    2b6c:       4e56 fb70       linkw %fp,#-1168
  68                 #  1df770:       defc ffe4       addaw #-28,%sp
  69                 $re = qr/.*(?:linkw %fp,|addaw )#-([0-9]{1,4})(?:,%sp)?$/o;
  70         } elsif ($arch eq 'mips64') {
  71                 #8800402c:       67bdfff0        daddiu  sp,sp,-16
  72                 $re = qr/.*daddiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
  73         } elsif ($arch eq 'mips') {
  74                 #88003254:       27bdffe0        addiu   sp,sp,-32
  75                 $re = qr/.*addiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
  76         } elsif ($arch eq 'nios2') {
  77                 #25a8:  defffb04        addi    sp,sp,-20
  78                 $re = qr/.*addi.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
  79         } elsif ($arch eq 'openrisc') {
  80                 # c000043c:       9c 21 fe f0     l.addi r1,r1,-272
  81                 $re = qr/.*l\.addi.*r1,r1,-(([0-9]{2}|[3-9])[0-9]{2})/o;
  82         } elsif ($arch eq 'parisc' || $arch eq 'parisc64') {
  83                 $re = qr/.*ldo ($x{1,8})\(sp\),sp/o;
  84         } elsif ($arch eq 'powerpc' || $arch =~ /^ppc(64)?(le)?$/ ) {
  85                 # powerpc    : 94 21 ff 30     stwu    r1,-208(r1)
  86                 # ppc64(le)  : 81 ff 21 f8     stdu    r1,-128(r1)
  87                 $re = qr/.*st[dw]u.*r1,-($x{1,8})\(r1\)/o;
  88         } elsif ($arch =~ /^s390x?$/) {
  89                 #   11160:       a7 fb ff 60             aghi   %r15,-160
  90                 # or
  91                 #  100092:       e3 f0 ff c8 ff 71       lay     %r15,-56(%r15)
  92                 $re = qr/.*(?:lay|ag?hi).*\%r15,-(([0-9]{2}|[3-9])[0-9]{2})
  93                       (?:\(\%r15\))?$/ox;
  94         } elsif ($arch =~ /^sh64$/) {
  95                 #XXX: we only check for the immediate case presently,
  96                 #     though we will want to check for the movi/sub
  97                 #     pair for larger users. -- PFM.
  98                 #a00048e0:       d4fc40f0        addi.l  r15,-240,r15
  99                 $re = qr/.*addi\.l.*r15,-(([0-9]{2}|[3-9])[0-9]{2}),r15/o;
 100         } elsif ($arch eq 'sparc' || $arch eq 'sparc64') {
 101                 # f0019d10:       9d e3 bf 90     save  %sp, -112, %sp
 102                 $re = qr/.*save.*%sp, -(([0-9]{2}|[3-9])[0-9]{2}), %sp/o;
 103         } else {
 104                 print("wrong or unknown architecture \"$arch\"\n");
 105                 exit
 106         }
 107 }
 108
 109 #
 110 # main()
 111 #
 112 my ($func, $file, $lastslash);
 113
 114 while (my $line = <STDIN>) {
 115         if ($line =~ m/$funcre/) {
 116                 $func = $1;
 117         }
 118         elsif ($line =~ m/(.*):\s*file format/) {
 119                 $file = $1;
 120                 $file =~ s/\.ko//;
 121                 $lastslash = rindex($file, "/");
 122                 if ($lastslash != -1) {
 123                         $file = substr($file, $lastslash + 1);
 124                 }
 125         }
 126         elsif ($line =~ m/$re/) {
 127                 my $size = $1;
 128                 $size = hex($size) if ($size =~ /^0x/);
 129
 130                 if ($size > 0xf0000000) {
 131                         $size = - $size;
 132                         $size += 0x80000000;
 133                         $size += 0x80000000;
 134                 }
 135                 next if ($size > 0x10000000);
 136
 137                 next if $line !~ m/^($xs*)/;
 138                 my $addr = $1;
 139                 $addr =~ s/ /0/g;
 140                 $addr = "0x$addr";
 141
 142                 my $intro = "$addr $func [$file]:";
 143                 my $padlen = 56 - length($intro);
 144                 while ($padlen > 0) {
 145                         $intro .= '     ';
 146                         $padlen -= 8;
 147                 }
 148                 next if ($size < 100);
 149                 push @stack, "$intro$size\n";
 150         }
 151         elsif (defined $dre && $line =~ m/$dre/) {
 152                 my $size = "Dynamic ($1)";
 153
 154                 next if $line !~ m/^($xs*)/;
 155                 my $addr = $1;
 156                 $addr =~ s/ /0/g;
 157                 $addr = "0x$addr";
 158
 159                 my $intro = "$addr $func [$file]:";
 160                 my $padlen = 56 - length($intro);
 161                 while ($padlen > 0) {
 162                         $intro .= '     ';
 163                         $padlen -= 8;
 164                 }
 165                 push @stack, "$intro$size\n";
 166         }
 167 }
 168
 169 # Sort output by size (last field)
 170 print sort { ($b =~ /:\t*(\d+)$/)[0] <=> ($a =~ /:\t*(\d+)$/)[0] } @stack;