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 #       Arm port by Holger Schurig
  12 #       Random bits by Matt Mackall <mpm@selenic.com>
  13 #       M68k port by Geert Uytterhoeven and Andreas Schwab
  14 #       AArch64, PARISC ports by Kyle McMartin
  15 #       sparc port by Martin Habets <errandir_news@mph.eclipse.co.uk>
  16 #       ppc64le port by Breno Leitao <leitao@debian.org>
  17 #       riscv port by Wadim Mueller <wafgo01@gmail.com>
  18 #       loongarch port by Youling Tang <tangyouling@kylinos.cn>
  19 #
  20 #       Usage:
  21 #       objdump -d vmlinux | scripts/checkstack.pl [arch] [min_stack]
  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 # $sub: subroutine for special handling to check stack usage.
  38 #
  39 # use anything else and feel the pain ;)
  40 my (@stack, $re, $dre, $sub, $x, $xs, $funcre, $min_stack);
  41 {
  42         my $arch = shift;
  43         if ($arch eq "") {
  44                 $arch = `uname -m`;
  45                 chomp($arch);
  46         }
  47
  48         $min_stack = shift;
  49         if ($min_stack eq "" || $min_stack !~ /^\d+$/) {
  50                 $min_stack = 512;
  51         }
  52
  53         $x      = "[0-9a-f]";   # hex character
  54         $xs     = "[0-9a-f ]";  # hex character or space
  55         $funcre = qr/^$x* <(.*)>:$/;
  56         if ($arch =~ '^(aarch|arm)64$') {
  57                 #ffffffc0006325cc:       a9bb7bfd        stp     x29, x30, [sp, #-80]!
  58                 #a110:       d11643ff        sub     sp, sp, #0x590
  59                 $re = qr/^.*stp.*sp, ?\#-([0-9]{1,8})\]\!/o;
  60                 $dre = qr/^.*sub.*sp, sp, #(0x$x{1,8})/o;
  61         } elsif ($arch eq 'arm') {
  62                 #c0008ffc:      e24dd064        sub     sp, sp, #100    ; 0x64
  63                 $re = qr/.*sub.*sp, sp, #([0-9]{1,4})/o;
  64                 $sub = \&arm_push_handling;
  65         } elsif ($arch =~ /^x86(_64)?$/ || $arch =~ /^i[3456]86$/) {
  66                 #c0105234:       81 ec ac 05 00 00       sub    $0x5ac,%esp
  67                 # or
  68                 #    2f60:    48 81 ec e8 05 00 00       sub    $0x5e8,%rsp
  69                 $re = qr/^.*[as][du][db]    \$(0x$x{1,8}),\%(e|r)sp$/o;
  70                 $dre = qr/^.*[as][du][db]    (%.*),\%(e|r)sp$/o;
  71         } elsif ($arch eq 'm68k') {
  72                 #    2b6c:       4e56 fb70       linkw %fp,#-1168
  73                 #  1df770:       defc ffe4       addaw #-28,%sp
  74                 $re = qr/.*(?:linkw %fp,|addaw )#-([0-9]{1,4})(?:,%sp)?$/o;
  75         } elsif ($arch eq 'mips64') {
  76                 #8800402c:       67bdfff0        daddiu  sp,sp,-16
  77                 $re = qr/.*daddiu.*sp,sp,-([0-9]{1,8})/o;
  78         } elsif ($arch eq 'mips') {
  79                 #88003254:       27bdffe0        addiu   sp,sp,-32
  80                 $re = qr/.*addiu.*sp,sp,-([0-9]{1,8})/o;
  81         } elsif ($arch eq 'nios2') {
  82                 #25a8:  defffb04        addi    sp,sp,-20
  83                 $re = qr/.*addi.*sp,sp,-([0-9]{1,8})/o;
  84         } elsif ($arch eq 'openrisc') {
  85                 # c000043c:       9c 21 fe f0     l.addi r1,r1,-272
  86                 $re = qr/.*l\.addi.*r1,r1,-([0-9]{1,8})/o;
  87         } elsif ($arch eq 'parisc' || $arch eq 'parisc64') {
  88                 $re = qr/.*ldo ($x{1,8})\(sp\),sp/o;
  89         } elsif ($arch eq 'powerpc' || $arch =~ /^ppc(64)?(le)?$/ ) {
  90                 # powerpc    : 94 21 ff 30     stwu    r1,-208(r1)
  91                 # ppc64(le)  : 81 ff 21 f8     stdu    r1,-128(r1)
  92                 $re = qr/.*st[dw]u.*r1,-($x{1,8})\(r1\)/o;
  93         } elsif ($arch =~ /^s390x?$/) {
  94                 #   11160:       a7 fb ff 60             aghi   %r15,-160
  95                 # or
  96                 #  100092:       e3 f0 ff c8 ff 71       lay     %r15,-56(%r15)
  97                 $re = qr/.*(?:lay|ag?hi).*\%r15,-([0-9]+)(?:\(\%r15\))?$/o;
  98         } elsif ($arch eq 'sparc' || $arch eq 'sparc64') {
  99                 # f0019d10:       9d e3 bf 90     save  %sp, -112, %sp
 100                 $re = qr/.*save.*%sp, -([0-9]{1,8}), %sp/o;
 101         } elsif ($arch =~ /^riscv(64)?$/) {
 102                 #ffffffff8036e868:      c2010113                addi    sp,sp,-992
 103                 $re = qr/.*addi.*sp,sp,-([0-9]{1,8})/o;
 104         } elsif ($arch =~ /^loongarch(32|64)?$/) {
 105                 #9000000000224708:      02ff4063                addi.d  $sp, $sp, -48(0xfd0)
 106                 $re = qr/.*addi\..*sp, .*sp, -([0-9]{1,8}).*/o;
 107         } else {
 108                 print("wrong or unknown architecture \"$arch\"\n");
 109                 exit
 110         }
 111 }
 112
 113 #
 114 # To count stack usage of push {*, fp, ip, lr, pc} instruction in ARM,
 115 # if FRAME POINTER is enabled.
 116 # e.g. c01f0d48: e92ddff0 push {r4, r5, r6, r7, r8, r9, sl, fp, ip, lr, pc}
 117 #
 118 sub arm_push_handling {
 119         my $regex = qr/.*push.*fp, ip, lr, pc}/o;
 120         my $size = 0;
 121         my $line_arg = shift;
 122
 123         if ($line_arg =~ m/$regex/) {
 124                 $size = $line_arg =~ tr/,//;
 125                 $size = ($size + 1) * 4;
 126         }
 127
 128         return $size;
 129 }
 130
 131 #
 132 # main()
 133 #
 134 my ($func, $file, $lastslash, $total_size, $addr, $intro);
 135
 136 $total_size = 0;
 137
 138 while (my $line = <STDIN>) {
 139         if ($line =~ m/$funcre/) {
 140                 $func = $1;
 141                 next if $line !~ m/^($x*)/;
 142                 if ($total_size > $min_stack) {
 143                         push @stack, "$intro$total_size\n";
 144                 }
 145                 $addr = "0x$1";
 146                 $intro = "$addr $func [$file]:";
 147                 my $padlen = 56 - length($intro);
 148                 while ($padlen > 0) {
 149                         $intro .= '     ';
 150                         $padlen -= 8;
 151                 }
 152
 153                 $total_size = 0;
 154         }
 155         elsif ($line =~ m/(.*):\s*file format/) {
 156                 $file = $1;
 157                 $file =~ s/\.ko//;
 158                 $lastslash = rindex($file, "/");
 159                 if ($lastslash != -1) {
 160                         $file = substr($file, $lastslash + 1);
 161                 }
 162         }
 163         elsif ($line =~ m/$re/) {
 164                 my $size = $1;
 165                 $size = hex($size) if ($size =~ /^0x/);
 166
 167                 if ($size > 0xf0000000) {
 168                         $size = - $size;
 169                         $size += 0x80000000;
 170                         $size += 0x80000000;
 171                 }
 172                 next if ($size > 0x10000000);
 173
 174                 $total_size += $size;
 175         }
 176         elsif (defined $dre && $line =~ m/$dre/) {
 177                 my $size = $1;
 178
 179                 $size = hex($size) if ($size =~ /^0x/);
 180                 $total_size += $size;
 181         }
 182         elsif (defined $sub) {
 183                 my $size = &$sub($line);
 184
 185                 $total_size += $size;
 186         }
 187 }
 188 if ($total_size > $min_stack) {
 189         push @stack, "$intro$total_size\n";
 190 }
 191
 192 # Sort output by size (last field) and function name if size is the same
 193 sub sort_lines {
 194         my ($a, $b) = @_;
 195
 196         my $num_a = $1 if $a =~ /:\t*(\d+)$/;
 197         my $num_b = $1 if $b =~ /:\t*(\d+)$/;
 198         my $func_a = $1 if $a =~ / (.*):/;
 199         my $func_b = $1 if $b =~ / (.*):/;
 200
 201         if ($num_a != $num_b) {
 202                 return $num_b <=> $num_a;
 203         } else {
 204                 return $func_a cmp $func_b;
 205         }
 206 }
 207
 208 print sort { sort_lines($a, $b) } @stack;