diff options
Diffstat (limited to 'arch/x86/tools')
-rw-r--r-- | arch/x86/tools/calc_run_size.pl | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/arch/x86/tools/calc_run_size.pl b/arch/x86/tools/calc_run_size.pl new file mode 100644 index 000000000000..23210baade2d --- /dev/null +++ b/arch/x86/tools/calc_run_size.pl @@ -0,0 +1,39 @@ +#!/usr/bin/perl +# +# Calculate the amount of space needed to run the kernel, including room for +# the .bss and .brk sections. +# +# Usage: +# objdump -h a.out | perl calc_run_size.pl +use strict; + +my $mem_size = 0; +my $file_offset = 0; + +my $sections=" *[0-9]+ \.(?:bss|brk) +"; +while (<>) { + if (/^$sections([0-9a-f]+) +(?:[0-9a-f]+ +){2}([0-9a-f]+)/) { + my $size = hex($1); + my $offset = hex($2); + $mem_size += $size; + if ($file_offset == 0) { + $file_offset = $offset; + } elsif ($file_offset != $offset) { + # BFD linker shows the same file offset in ELF. + # Gold linker shows them as consecutive. + next if ($file_offset + $mem_size == $offset + $size); + + printf STDERR "file_offset: 0x%lx\n", $file_offset; + printf STDERR "mem_size: 0x%lx\n", $mem_size; + printf STDERR "offset: 0x%lx\n", $offset; + printf STDERR "size: 0x%lx\n", $size; + + die ".bss and .brk are non-contiguous\n"; + } + } +} + +if ($file_offset == 0) { + die "Never found .bss or .brk file offset\n"; +} +printf("%d\n", $mem_size + $file_offset); |