455 lines
13 KiB
Prolog
455 lines
13 KiB
Prolog
#!/usr/bin/perl -w
|
|
#
|
|
# namespace.pl. Mon Aug 30 2004
|
|
#
|
|
# Perform a name space analysis on the linux kernel.
|
|
#
|
|
# Copyright Keith Owens <kaos@ocs.com.au>. GPL.
|
|
#
|
|
# Invoke by changing directory to the top of the kernel object
|
|
# tree then namespace.pl, no parameters.
|
|
#
|
|
# Tuned for 2.1.x kernels with the new module handling, it will
|
|
# work with 2.0 kernels as well.
|
|
#
|
|
# Last change 2.6.9-rc1, adding support for separate source and object
|
|
# trees.
|
|
#
|
|
# The source must be compiled/assembled first, the object files
|
|
# are the primary input to this script. Incomplete or missing
|
|
# objects will result in a flawed analysis. Compile both vmlinux
|
|
# and modules.
|
|
#
|
|
# Even with complete objects, treat the result of the analysis
|
|
# with caution. Some external references are only used by
|
|
# certain architectures, others with certain combinations of
|
|
# configuration parameters. Ideally the source should include
|
|
# something like
|
|
#
|
|
# #ifndef CONFIG_...
|
|
# static
|
|
# #endif
|
|
# symbol_definition;
|
|
#
|
|
# so the symbols are defined as static unless a particular
|
|
# CONFIG_... requires it to be external.
|
|
#
|
|
# A symbol that is suffixed with '(export only)' has these properties
|
|
#
|
|
# * It is global.
|
|
# * It is marked EXPORT_SYMBOL or EXPORT_SYMBOL_GPL, either in the same
|
|
# source file or a different source file.
|
|
# * Given the current .config, nothing uses the symbol.
|
|
#
|
|
# The symbol is a candidate for conversion to static, plus removal of the
|
|
# export. But be careful that a different .config might use the symbol.
|
|
#
|
|
#
|
|
# Name space analysis and cleanup is an iterative process. You cannot
|
|
# expect to find all the problems in a single pass.
|
|
#
|
|
# * Identify possibly unnecessary global declarations, verify that they
|
|
# really are unnecessary and change them to static.
|
|
# * Compile and fix up gcc warnings about static, removing dead symbols
|
|
# as necessary.
|
|
# * make clean and rebuild with different configs (especially
|
|
# CONFIG_MODULES=n) to see which symbols are being defined when the
|
|
# config does not require them. These symbols bloat the kernel object
|
|
# for no good reason, which is frustrating for embedded systems.
|
|
# * Wrap config sensitive symbols in #ifdef CONFIG_foo, as long as the
|
|
# code does not get too ugly.
|
|
# * Repeat the name space analysis until you can live with with the
|
|
# result.
|
|
#
|
|
|
|
require 5; # at least perl 5
|
|
use strict;
|
|
use File::Find;
|
|
|
|
my $nm = "/usr/bin/nm -p";
|
|
my $objdump = "/usr/bin/objdump -s -j .comment";
|
|
my $srctree = "";
|
|
my $objtree = "";
|
|
$srctree = "$ENV{'srctree'}/" if (exists($ENV{'srctree'}));
|
|
$objtree = "$ENV{'objtree'}/" if (exists($ENV{'objtree'}));
|
|
|
|
if ($#ARGV != -1) {
|
|
print STDERR "usage: $0 takes no parameters\n";
|
|
die("giving up\n");
|
|
}
|
|
|
|
my %nmdata = (); # nm data for each object
|
|
my %def = (); # all definitions for each name
|
|
my %ksymtab = (); # names that appear in __ksymtab_
|
|
my %ref = (); # $ref{$name} exists if there is a true external reference to $name
|
|
my %export = (); # $export{$name} exists if there is an EXPORT_... of $name
|
|
|
|
&find(\&linux_objects, '.'); # find the objects and do_nm on them
|
|
&list_multiply_defined();
|
|
&resolve_external_references();
|
|
&list_extra_externals();
|
|
|
|
exit(0);
|
|
|
|
sub linux_objects
|
|
{
|
|
# Select objects, ignoring objects which are only created by
|
|
# merging other objects. Also ignore all of modules, scripts
|
|
# and compressed. Most conglomerate objects are handled by do_nm,
|
|
# this list only contains the special cases. These include objects
|
|
# that are linked from just one other object and objects for which
|
|
# there is really no permanent source file.
|
|
my $basename = $_;
|
|
$_ = $File::Find::name;
|
|
s:^\./::;
|
|
if (/.*\.o$/ &&
|
|
! (
|
|
m:/built-in.o$:
|
|
|| m:arch/i386/kernel/vsyscall-syms.o$:
|
|
|| m:arch/ia64/ia32/ia32.o$:
|
|
|| m:arch/ia64/kernel/gate-syms.o$:
|
|
|| m:arch/ia64/lib/__divdi3.o$:
|
|
|| m:arch/ia64/lib/__divsi3.o$:
|
|
|| m:arch/ia64/lib/__moddi3.o$:
|
|
|| m:arch/ia64/lib/__modsi3.o$:
|
|
|| m:arch/ia64/lib/__udivdi3.o$:
|
|
|| m:arch/ia64/lib/__udivsi3.o$:
|
|
|| m:arch/ia64/lib/__umoddi3.o$:
|
|
|| m:arch/ia64/lib/__umodsi3.o$:
|
|
|| m:arch/ia64/scripts/check_gas_for_hint.o$:
|
|
|| m:arch/ia64/sn/kernel/xp.o$:
|
|
|| m:boot/bbootsect.o$:
|
|
|| m:boot/bsetup.o$:
|
|
|| m:/bootsect.o$:
|
|
|| m:/boot/setup.o$:
|
|
|| m:/compressed/:
|
|
|| m:drivers/cdrom/driver.o$:
|
|
|| m:drivers/char/drm/tdfx_drv.o$:
|
|
|| m:drivers/ide/ide-detect.o$:
|
|
|| m:drivers/ide/pci/idedriver-pci.o$:
|
|
|| m:drivers/media/media.o$:
|
|
|| m:drivers/scsi/sd_mod.o$:
|
|
|| m:drivers/video/video.o$:
|
|
|| m:fs/devpts/devpts.o$:
|
|
|| m:fs/exportfs/exportfs.o$:
|
|
|| m:fs/hugetlbfs/hugetlbfs.o$:
|
|
|| m:fs/msdos/msdos.o$:
|
|
|| m:fs/nls/nls.o$:
|
|
|| m:fs/ramfs/ramfs.o$:
|
|
|| m:fs/romfs/romfs.o$:
|
|
|| m:fs/vfat/vfat.o$:
|
|
|| m:init/mounts.o$:
|
|
|| m:^modules/:
|
|
|| m:net/netlink/netlink.o$:
|
|
|| m:net/sched/sched.o$:
|
|
|| m:/piggy.o$:
|
|
|| m:^scripts/:
|
|
|| m:sound/.*/snd-:
|
|
|| m:^.*/\.tmp_:
|
|
|| m:^\.tmp_:
|
|
|| m:/vmlinux-obj.o$:
|
|
)
|
|
) {
|
|
do_nm($basename, $_);
|
|
}
|
|
$_ = $basename; # File::Find expects $_ untouched (undocumented)
|
|
}
|
|
|
|
sub do_nm
|
|
{
|
|
my ($basename, $fullname) = @_;
|
|
my ($source, $type, $name);
|
|
if (! -e $basename) {
|
|
printf STDERR "$basename does not exist\n";
|
|
return;
|
|
}
|
|
if ($fullname !~ /\.o$/) {
|
|
printf STDERR "$fullname is not an object file\n";
|
|
return;
|
|
}
|
|
($source = $fullname) =~ s/\.o$//;
|
|
if (-e "$objtree$source.c" || -e "$objtree$source.S") {
|
|
$source = "$objtree$source";
|
|
} else {
|
|
$source = "$srctree$source";
|
|
}
|
|
if (! -e "$source.c" && ! -e "$source.S") {
|
|
# No obvious source, exclude the object if it is conglomerate
|
|
if (! open(OBJDUMPDATA, "$objdump $basename|")) {
|
|
printf STDERR "$objdump $fullname failed $!\n";
|
|
return;
|
|
}
|
|
my $comment;
|
|
while (<OBJDUMPDATA>) {
|
|
chomp();
|
|
if (/^In archive/) {
|
|
# Archives are always conglomerate
|
|
$comment = "GCC:GCC:";
|
|
last;
|
|
}
|
|
next if (! /^[ 0-9a-f]{5,} /);
|
|
$comment .= substr($_, 43);
|
|
}
|
|
close(OBJDUMPDATA);
|
|
if (!defined($comment) || $comment !~ /GCC\:.*GCC\:/m) {
|
|
printf STDERR "No source file found for $fullname\n";
|
|
}
|
|
return;
|
|
}
|
|
if (! open(NMDATA, "$nm $basename|")) {
|
|
printf STDERR "$nm $fullname failed $!\n";
|
|
return;
|
|
}
|
|
my @nmdata;
|
|
while (<NMDATA>) {
|
|
chop;
|
|
($type, $name) = (split(/ +/, $_, 3))[1..2];
|
|
# Expected types
|
|
# A absolute symbol
|
|
# B weak external reference to data that has been resolved
|
|
# C global variable, uninitialised
|
|
# D global variable, initialised
|
|
# G global variable, initialised, small data section
|
|
# R global array, initialised
|
|
# S global variable, uninitialised, small bss
|
|
# T global label/procedure
|
|
# U external reference
|
|
# W weak external reference to text that has been resolved
|
|
# a assembler equate
|
|
# b static variable, uninitialised
|
|
# d static variable, initialised
|
|
# g static variable, initialised, small data section
|
|
# r static array, initialised
|
|
# s static variable, uninitialised, small bss
|
|
# t static label/procedures
|
|
# w weak external reference to text that has not been resolved
|
|
# ? undefined type, used a lot by modules
|
|
if ($type !~ /^[ABCDGRSTUWabdgrstw?]$/) {
|
|
printf STDERR "nm output for $fullname contains unknown type '$_'\n";
|
|
}
|
|
elsif ($name =~ /\./) {
|
|
# name with '.' is local static
|
|
}
|
|
else {
|
|
$type = 'R' if ($type eq '?'); # binutils replaced ? with R at one point
|
|
# binutils keeps changing the type for exported symbols, force it to R
|
|
$type = 'R' if ($name =~ /^__ksymtab/ || $name =~ /^__kstrtab/);
|
|
$name =~ s/_R[a-f0-9]{8}$//; # module versions adds this
|
|
if ($type =~ /[ABCDGRSTW]/ &&
|
|
$name ne 'init_module' &&
|
|
$name ne 'cleanup_module' &&
|
|
$name ne 'Using_Versions' &&
|
|
$name !~ /^Version_[0-9]+$/ &&
|
|
$name !~ /^__parm_/ &&
|
|
$name !~ /^__kstrtab/ &&
|
|
$name !~ /^__ksymtab/ &&
|
|
$name !~ /^__kcrctab_/ &&
|
|
$name !~ /^__exitcall_/ &&
|
|
$name !~ /^__initcall_/ &&
|
|
$name !~ /^__kdb_initcall_/ &&
|
|
$name !~ /^__kdb_exitcall_/ &&
|
|
$name !~ /^__module_/ &&
|
|
$name !~ /^__mod_/ &&
|
|
$name !~ /^__crc_/ &&
|
|
$name ne '__this_module' &&
|
|
$name ne 'kernel_version') {
|
|
if (!exists($def{$name})) {
|
|
$def{$name} = [];
|
|
}
|
|
push(@{$def{$name}}, $fullname);
|
|
}
|
|
push(@nmdata, "$type $name");
|
|
if ($name =~ /^__ksymtab_/) {
|
|
$name = substr($name, 10);
|
|
if (!exists($ksymtab{$name})) {
|
|
$ksymtab{$name} = [];
|
|
}
|
|
push(@{$ksymtab{$name}}, $fullname);
|
|
}
|
|
}
|
|
}
|
|
close(NMDATA);
|
|
if ($#nmdata < 0) {
|
|
if (
|
|
$fullname ne "lib/brlock.o"
|
|
&& $fullname ne "lib/dec_and_lock.o"
|
|
&& $fullname ne "fs/xfs/xfs_macros.o"
|
|
&& $fullname ne "drivers/ide/ide-probe-mini.o"
|
|
&& $fullname ne "usr/initramfs_data.o"
|
|
&& $fullname ne "drivers/acpi/executer/exdump.o"
|
|
&& $fullname ne "drivers/acpi/resources/rsdump.o"
|
|
&& $fullname ne "drivers/acpi/namespace/nsdumpdv.o"
|
|
&& $fullname ne "drivers/acpi/namespace/nsdump.o"
|
|
&& $fullname ne "arch/ia64/sn/kernel/sn2/io.o"
|
|
&& $fullname ne "arch/ia64/kernel/gate-data.o"
|
|
&& $fullname ne "drivers/ieee1394/oui.o"
|
|
&& $fullname ne "security/capability.o"
|
|
&& $fullname ne "sound/core/wrappers.o"
|
|
&& $fullname ne "fs/ntfs/sysctl.o"
|
|
&& $fullname ne "fs/jfs/jfs_debug.o"
|
|
) {
|
|
printf "No nm data for $fullname\n";
|
|
}
|
|
return;
|
|
}
|
|
$nmdata{$fullname} = \@nmdata;
|
|
}
|
|
|
|
sub drop_def
|
|
{
|
|
my ($object, $name) = @_;
|
|
my $nmdata = $nmdata{$object};
|
|
my ($i, $j);
|
|
for ($i = 0; $i <= $#{$nmdata}; ++$i) {
|
|
if ($name eq (split(' ', $nmdata->[$i], 2))[1]) {
|
|
splice(@{$nmdata{$object}}, $i, 1);
|
|
my $def = $def{$name};
|
|
for ($j = 0; $j < $#{$def{$name}}; ++$j) {
|
|
if ($def{$name}[$j] eq $object) {
|
|
splice(@{$def{$name}}, $j, 1);
|
|
}
|
|
}
|
|
last;
|
|
}
|
|
}
|
|
}
|
|
|
|
sub list_multiply_defined
|
|
{
|
|
my ($name, $module);
|
|
foreach $name (keys(%def)) {
|
|
if ($#{$def{$name}} > 0) {
|
|
# Special case for cond_syscall
|
|
if ($#{$def{$name}} == 1 && $name =~ /^sys_/ &&
|
|
($def{$name}[0] eq "kernel/sys.o" ||
|
|
$def{$name}[1] eq "kernel/sys.o")) {
|
|
&drop_def("kernel/sys.o", $name);
|
|
next;
|
|
}
|
|
# Special case for i386 entry code
|
|
if ($#{$def{$name}} == 1 && $name =~ /^__kernel_/ &&
|
|
$def{$name}[0] eq "arch/i386/kernel/vsyscall-int80.o" &&
|
|
$def{$name}[1] eq "arch/i386/kernel/vsyscall-sysenter.o") {
|
|
&drop_def("arch/i386/kernel/vsyscall-sysenter.o", $name);
|
|
next;
|
|
}
|
|
printf "$name is multiply defined in :-\n";
|
|
foreach $module (@{$def{$name}}) {
|
|
printf "\t$module\n";
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
sub resolve_external_references
|
|
{
|
|
my ($object, $type, $name, $i, $j, $kstrtab, $ksymtab, $export);
|
|
printf "\n";
|
|
foreach $object (keys(%nmdata)) {
|
|
my $nmdata = $nmdata{$object};
|
|
for ($i = 0; $i <= $#{$nmdata}; ++$i) {
|
|
($type, $name) = split(' ', $nmdata->[$i], 2);
|
|
if ($type eq "U" || $type eq "w") {
|
|
if (exists($def{$name}) || exists($ksymtab{$name})) {
|
|
# add the owning object to the nmdata
|
|
$nmdata->[$i] = "$type $name $object";
|
|
# only count as a reference if it is not EXPORT_...
|
|
$kstrtab = "R __kstrtab_$name";
|
|
$ksymtab = "R __ksymtab_$name";
|
|
$export = 0;
|
|
for ($j = 0; $j <= $#{$nmdata}; ++$j) {
|
|
if ($nmdata->[$j] eq $kstrtab ||
|
|
$nmdata->[$j] eq $ksymtab) {
|
|
$export = 1;
|
|
last;
|
|
}
|
|
}
|
|
if ($export) {
|
|
$export{$name} = "";
|
|
}
|
|
else {
|
|
$ref{$name} = ""
|
|
}
|
|
}
|
|
elsif ( $name ne "mod_use_count_"
|
|
&& $name ne "__initramfs_end"
|
|
&& $name ne "__initramfs_start"
|
|
&& $name ne "_einittext"
|
|
&& $name ne "_sinittext"
|
|
&& $name ne "kallsyms_names"
|
|
&& $name ne "kallsyms_num_syms"
|
|
&& $name ne "kallsyms_addresses"
|
|
&& $name ne "__this_module"
|
|
&& $name ne "_etext"
|
|
&& $name ne "_edata"
|
|
&& $name ne "_end"
|
|
&& $name ne "__bss_start"
|
|
&& $name ne "_text"
|
|
&& $name ne "_stext"
|
|
&& $name ne "__gp"
|
|
&& $name ne "ia64_unw_start"
|
|
&& $name ne "ia64_unw_end"
|
|
&& $name ne "__init_begin"
|
|
&& $name ne "__init_end"
|
|
&& $name ne "__bss_stop"
|
|
&& $name ne "__nosave_begin"
|
|
&& $name ne "__nosave_end"
|
|
&& $name ne "pg0"
|
|
&& $name ne "__module_text_address"
|
|
&& $name !~ /^__sched_text_/
|
|
&& $name !~ /^__start_/
|
|
&& $name !~ /^__end_/
|
|
&& $name !~ /^__stop_/
|
|
&& $name !~ /^__scheduling_functions_.*_here/
|
|
&& $name !~ /^__.*initcall_/
|
|
&& $name !~ /^__.*per_cpu_start/
|
|
&& $name !~ /^__.*per_cpu_end/
|
|
&& $name !~ /^__alt_instructions/
|
|
&& $name !~ /^__setup_/
|
|
&& $name !~ /^jiffies/
|
|
&& $name !~ /^__mod_timer/
|
|
&& $name !~ /^__mod_page_state/
|
|
&& $name !~ /^init_module/
|
|
&& $name !~ /^cleanup_module/
|
|
) {
|
|
printf "Cannot resolve ";
|
|
printf "weak " if ($type eq "w");
|
|
printf "reference to $name from $object\n";
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
sub list_extra_externals
|
|
{
|
|
my %noref = ();
|
|
my ($name, @module, $module, $export);
|
|
foreach $name (keys(%def)) {
|
|
if (! exists($ref{$name})) {
|
|
@module = @{$def{$name}};
|
|
foreach $module (@module) {
|
|
if (! exists($noref{$module})) {
|
|
$noref{$module} = [];
|
|
}
|
|
push(@{$noref{$module}}, $name);
|
|
}
|
|
}
|
|
}
|
|
if (%noref) {
|
|
printf "\nExternally defined symbols with no external references\n";
|
|
foreach $module (sort(keys(%noref))) {
|
|
printf " $module\n";
|
|
foreach (sort(@{$noref{$module}})) {
|
|
if (exists($export{$_})) {
|
|
$export = " (export only)";
|
|
}
|
|
else {
|
|
$export = "";
|
|
}
|
|
printf " $_$export\n";
|
|
}
|
|
}
|
|
}
|
|
}
|