the-tree/scripts/checkstack.pl

0001 #!/usr/bin/env perl
0002 # SPDX-License-Identifier: GPL-2.0
0003
0004 #   Check the stack usage of functions
0005 #
0006 #   Copyright Joern Engel <joern@lazybastard.org>
0007 #   Inspired by Linus Torvalds
0008 #   Original idea maybe from Keith Owens
0009 #   s390 port and big speedup by Arnd Bergmann <arnd@bergmann-dalldorf.de>
0010 #   Mips port by Juan Quintela <quintela@mandrakesoft.com>
0011 #   IA64 port via Andreas Dilger
0012 #   Arm port by Holger Schurig
0013 #   sh64 port by Paul Mundt
0014 #   Random bits by Matt Mackall <mpm@selenic.com>
0015 #   M68k port by Geert Uytterhoeven and Andreas Schwab
0016 #   AArch64, PARISC ports by Kyle McMartin
0017 #   sparc port by Martin Habets <errandir_news@mph.eclipse.co.uk>
0018 #   ppc64le port by Breno Leitao <leitao@debian.org>
0019 #   riscv port by Wadim Mueller <wafgo01@gmail.com>
0020 #
0021 #   Usage:
0022 #   objdump -d vmlinux | scripts/checkstack.pl [arch]
0023 #
0024 #   TODO :  Port to all architectures (one regex per arch)
0025
0026 use strict;
0027
0028 # check for arch
0029 #
0030 # $re is used for two matches:
0031 # $& (whole re) matches the complete objdump line with the stack growth
0032 # $1 (first bracket) matches the size of the stack growth
0033 #
0034 # $dre is similar, but for dynamic stack redutions:
0035 # $& (whole re) matches the complete objdump line with the stack growth
0036 # $1 (first bracket) matches the dynamic amount of the stack growth
0037 #
0038 # $sub: subroutine for special handling to check stack usage.
0039 #
0040 # use anything else and feel the pain ;)
0041 my (@stack, $re, $dre, $sub, $x, $xs, $funcre, $min_stack);
0042 {
0043     my $arch = shift;
0044     if ($arch eq "") {
0045         $arch = `uname -m`;
0046         chomp($arch);
0047     }
0048
0049     $min_stack = shift;
0050     if ($min_stack eq "" || $min_stack !~ /^\d+$/) {
0051         $min_stack = 100;
0052     }
0053
0054     $x  = "[0-9a-f]";   # hex character
0055     $xs = "[0-9a-f ]";  # hex character or space
0056     $funcre = qr/^$x* <(.*)>:$/;
0057     if ($arch =~ '^(aarch|arm)64$') {
0058         #ffffffc0006325cc:       a9bb7bfd        stp     x29, x30, [sp, #-80]!
0059         #a110:       d11643ff        sub     sp, sp, #0x590
0060         $re = qr/^.*stp.*sp, \#-([0-9]{1,8})\]\!/o;
0061         $dre = qr/^.*sub.*sp, sp, #(0x$x{1,8})/o;
0062     } elsif ($arch eq 'arm') {
0063         #c0008ffc:  e24dd064    sub sp, sp, #100    ; 0x64
0064         $re = qr/.*sub.*sp, sp, #([0-9]{1,4})/o;
0065         $sub = \&arm_push_handling;
0066     } elsif ($arch =~ /^x86(_64)?$/ || $arch =~ /^i[3456]86$/) {
0067         #c0105234:       81 ec ac 05 00 00       sub    $0x5ac,%esp
0068         # or
0069         #    2f60:    48 81 ec e8 05 00 00       sub    $0x5e8,%rsp
0070         $re = qr/^.*[as][du][db]    \$(0x$x{1,8}),\%(e|r)sp$/o;
0071         $dre = qr/^.*[as][du][db]    (%.*),\%(e|r)sp$/o;
0072     } elsif ($arch eq 'ia64') {
0073         #e0000000044011fc:       01 0f fc 8c     adds r12=-384,r12
0074         $re = qr/.*adds.*r12=-(([0-9]{2}|[3-9])[0-9]{2}),r12/o;
0075     } elsif ($arch eq 'm68k') {
0076         #    2b6c:       4e56 fb70       linkw %fp,#-1168
0077         #  1df770:       defc ffe4       addaw #-28,%sp
0078         $re = qr/.*(?:linkw %fp,|addaw )#-([0-9]{1,4})(?:,%sp)?$/o;
0079     } elsif ($arch eq 'mips64') {
0080         #8800402c:       67bdfff0        daddiu  sp,sp,-16
0081         $re = qr/.*daddiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
0082     } elsif ($arch eq 'mips') {
0083         #88003254:       27bdffe0        addiu   sp,sp,-32
0084         $re = qr/.*addiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
0085     } elsif ($arch eq 'nios2') {
0086         #25a8:  defffb04    addi    sp,sp,-20
0087         $re = qr/.*addi.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
0088     } elsif ($arch eq 'openrisc') {
0089         # c000043c:       9c 21 fe f0     l.addi r1,r1,-272
0090         $re = qr/.*l\.addi.*r1,r1,-(([0-9]{2}|[3-9])[0-9]{2})/o;
0091     } elsif ($arch eq 'parisc' || $arch eq 'parisc64') {
0092         $re = qr/.*ldo ($x{1,8})\(sp\),sp/o;
0093     } elsif ($arch eq 'powerpc' || $arch =~ /^ppc(64)?(le)?$/ ) {
0094         # powerpc    : 94 21 ff 30     stwu    r1,-208(r1)
0095         # ppc64(le)  : 81 ff 21 f8     stdu    r1,-128(r1)
0096         $re = qr/.*st[dw]u.*r1,-($x{1,8})\(r1\)/o;
0097     } elsif ($arch =~ /^s390x?$/) {
0098         #   11160:       a7 fb ff 60             aghi   %r15,-160
0099         # or
0100         #  100092:   e3 f0 ff c8 ff 71   lay     %r15,-56(%r15)
0101         $re = qr/.*(?:lay|ag?hi).*\%r15,-(([0-9]{2}|[3-9])[0-9]{2})
0102               (?:\(\%r15\))?$/ox;
0103     } elsif ($arch =~ /^sh64$/) {
0104         #XXX: we only check for the immediate case presently,
0105         #     though we will want to check for the movi/sub
0106         #     pair for larger users. -- PFM.
0107         #a00048e0:       d4fc40f0        addi.l  r15,-240,r15
0108         $re = qr/.*addi\.l.*r15,-(([0-9]{2}|[3-9])[0-9]{2}),r15/o;
0109     } elsif ($arch eq 'sparc' || $arch eq 'sparc64') {
0110         # f0019d10:       9d e3 bf 90     save  %sp, -112, %sp
0111         $re = qr/.*save.*%sp, -(([0-9]{2}|[3-9])[0-9]{2}), %sp/o;
0112     } elsif ($arch =~ /^riscv(64)?$/) {
0113         #ffffffff8036e868:  c2010113            addi    sp,sp,-992
0114         $re = qr/.*addi.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
0115     } else {
0116         print("wrong or unknown architecture \"$arch\"\n");
0117         exit
0118     }
0119 }
0120
0121 #
0122 # To count stack usage of push {*, fp, ip, lr, pc} instruction in ARM,
0123 # if FRAME POINTER is enabled.
0124 # e.g. c01f0d48: e92ddff0 push {r4, r5, r6, r7, r8, r9, sl, fp, ip, lr, pc}
0125 #
0126 sub arm_push_handling {
0127     my $regex = qr/.*push.*fp, ip, lr, pc}/o;
0128     my $size = 0;
0129     my $line_arg = shift;
0130
0131     if ($line_arg =~ m/$regex/) {
0132         $size = $line_arg =~ tr/,//;
0133         $size = ($size + 1) * 4;
0134     }
0135
0136     return $size;
0137 }
0138
0139 #
0140 # main()
0141 #
0142 my ($func, $file, $lastslash, $total_size, $addr, $intro);
0143
0144 $total_size = 0;
0145
0146 while (my $line = <STDIN>) {
0147     if ($line =~ m/$funcre/) {
0148         $func = $1;
0149         next if $line !~ m/^($xs*)/;
0150         if ($total_size > $min_stack) {
0151             push @stack, "$intro$total_size\n";
0152         }
0153
0154         $addr = $1;
0155         $addr =~ s/ /0/g;
0156         $addr = "0x$addr";
0157
0158         $intro = "$addr $func [$file]:";
0159         my $padlen = 56 - length($intro);
0160         while ($padlen > 0) {
0161             $intro .= ' ';
0162             $padlen -= 8;
0163         }
0164
0165         $total_size = 0;
0166     }
0167     elsif ($line =~ m/(.*):\s*file format/) {
0168         $file = $1;
0169         $file =~ s/\.ko//;
0170         $lastslash = rindex($file, "/");
0171         if ($lastslash != -1) {
0172             $file = substr($file, $lastslash + 1);
0173         }
0174     }
0175     elsif ($line =~ m/$re/) {
0176         my $size = $1;
0177         $size = hex($size) if ($size =~ /^0x/);
0178
0179         if ($size > 0xf0000000) {
0180             $size = - $size;
0181             $size += 0x80000000;
0182             $size += 0x80000000;
0183         }
0184         next if ($size > 0x10000000);
0185
0186         $total_size += $size;
0187     }
0188     elsif (defined $dre && $line =~ m/$dre/) {
0189         my $size = $1;
0190
0191         $size = hex($size) if ($size =~ /^0x/);
0192         $total_size += $size;
0193     }
0194     elsif (defined $sub) {
0195         my $size = &$sub($line);
0196
0197         $total_size += $size;
0198     }
0199 }
0200 if ($total_size > $min_stack) {
0201     push @stack, "$intro$total_size\n";
0202 }
0203
0204 # Sort output by size (last field)
0205 print sort { ($b =~ /:\t*(\d+)$/)[0] <=> ($a =~ /:\t*(\d+)$/)[0] } @stack;