3 # Copyright 2005-2009 - Steven Rostedt
4 # Licensed under the terms of the GNU GPL License version 2
6 # It's simple enough to figure out how this works.
7 # If not, then you can ask me at stripconfig@goodmis.org
11 # If you have installed a Linux kernel from a distribution
12 # that turns on way too many modules than you need, and
13 # you only want the modules you use, then this program
16 # It gives you the ability to turn off all the modules that are
17 # not loaded on your system.
21 # 1. Boot up the kernel that you want to stream line the config on.
22 # 2. Change directory to the directory holding the source of the
23 # kernel that you just booted.
24 # 3. Copy the configuraton file to this directory as .config
25 # 4. Have all your devices that you need modules for connected and
26 # operational (make sure that their corresponding modules are loaded)
27 # 5. Run this script redirecting the output to some other file
29 # 6. Back up your old config (if you want too).
30 # 7. copy the config_strip file to .config
31 # 8. Run "make oldconfig"
33 # Now your kernel is ready to be built with only the modules that
36 # Here's what I did with my Debian distribution.
38 # cd /usr/src/linux-2.6.10
39 # cp /boot/config-2.6.10-1-686-smp .config
40 # ~/bin/streamline_config > config_strip
41 # mv .config config_sav
42 # mv config_strip .config
47 my $config = ".config";
49 my $uname = `uname -r`;
58 "file" => "/proc/config.gz",
62 "file" => "/boot/config-$uname",
66 "file" => "/boot/vmlinuz-$uname",
67 "exec" => "scripts/extract-ikconfig",
68 "test" => "scripts/extract-ikconfig",
72 "exec" => "scripts/extract-ikconfig",
73 "test" => "scripts/extract-ikconfig",
76 "file" => "/lib/modules/$uname/kernel/kernel/configs.ko",
77 "exec" => "scripts/extract-ikconfig",
78 "test" => "scripts/extract-ikconfig",
81 "file" => "kernel/configs.ko",
82 "exec" => "scripts/extract-ikconfig",
83 "test" => "scripts/extract-ikconfig",
86 "file" => "kernel/configs.o",
87 "exec" => "scripts/extract-ikconfig",
88 "test" => "scripts/extract-ikconfig",
93 foreach my $conf (@searchconfigs) {
94 my $file = $conf->{"file"};
96 next if ( ! -f
"$file");
98 if (defined($conf->{"test"})) {
99 `$conf->{"test"} $conf->{"file"} 2>/dev/null`;
103 my $exec = $conf->{"exec"};
105 print STDERR
"using config: '$file'\n";
107 open(CIN
, "$exec $file |") || die "Failed to run $exec $file";
110 die "No config file found";
115 # Get the build source and top level Kconfig file (passed in)
116 my $ksource = $ARGV[0];
117 my $kconfig = $ARGV[1];
118 my $lsmod_file = $ARGV[2];
120 my @makefiles = `find $ksource -name Makefile 2>/dev/null`;
144 my $source = "$ksource/$kconfig";
145 my $last_source = "";
147 # Check for any environment variables used
148 while ($source =~ /\$(\w+)/ && $last_source ne $source) {
150 $last_source = $source;
151 $source =~ s/\$$env/$ENV{$env}/;
154 open(KIN
, "$source") || die "Can't open $kconfig";
158 # Make sure that lines ending with \ continue
160 $_ = $line . " " . $_;
171 # collect any Kconfig sources
172 if (/^source\s*"(.*)"/) {
173 $kconfigs[$#kconfigs+1] = $1;
177 if (/^\s*(menu)?config\s+(\S+)\s*$/) {
181 for (my $i = 0; $i < $iflevel; $i++) {
183 $depends{$config} .= " " . $ifdeps[$i];
185 $depends{$config} = $ifdeps[$i];
190 # collect the depends for the config
191 } elsif ($state eq "NEW" && /^\s*depends\s+on\s+(.*)$/) {
193 $depends{$config} = $1;
194 } elsif ($state eq "DEP" && /^\s*depends\s+on\s+(.*)$/) {
195 $depends{$config} .= " " . $1;
197 # Get the configs that select this config
198 } elsif ($state ne "NONE" && /^\s*select\s+(\S+)/) {
199 if (defined($selects{$1})) {
200 $selects{$1} .= " " . $config;
202 $selects{$1} = $config;
205 # configs without prompts must be selected
206 } elsif ($state ne "NONE" && /^\s*tristate\s\S/) {
207 # note if the config has a prompt
208 $prompts{$config} = 1;
210 # Check for if statements
211 } elsif (/^if\s+(.*\S)\s*$/) {
213 # remove beginning and ending non text
214 $deps =~ s/^[^a-zA-Z0-9_]*//;
215 $deps =~ s/[^a-zA-Z0-9_]*$//;
217 my @deps = split /[^a-zA-Z0-9_]+/, $deps;
219 $ifdeps[$iflevel++] = join ':', @deps;
223 $iflevel-- if ($iflevel);
226 } elsif (/^\s*help\s*$/) {
232 # read in any configs that were found.
233 foreach $kconfig (@kconfigs) {
234 if (!defined($read_kconfigs{$kconfig})) {
235 $read_kconfigs{$kconfig} = 1;
236 read_kconfig
($kconfig);
242 read_kconfig
($kconfig);
245 # Read all Makefiles to map the configs to the objects
246 foreach my $makefile (@makefiles) {
250 open(MIN
,$makefile) || die "Can't open $makefile";
252 # if this line ends with a backslash, continue
265 # collect objects after obj-$(CONFIG_FOO_BAR)
266 if (/obj-\$\((CONFIG_[^\)]*)\)\s*[+:]?=\s*(.*)/) {
270 if (defined($objs)) {
271 foreach my $obj (split /\s+/,$objs) {
273 if ($obj =~ /(.*)\.o$/) {
274 # Objects may be enabled by more than one config.
275 # Store configs in an array.
278 if (defined($objects{$1})) {
279 @arr = @
{$objects{$1}};
282 $arr[$#arr+1] = $var;
284 # The objects have a hash mapping to a reference
285 # of an array of configs.
286 $objects{$1} = \
@arr;
296 if (defined($lsmod_file)) {
297 if ( ! -f
$lsmod_file) {
298 die "$lsmod_file not found";
300 if ( -x
$lsmod_file) {
301 # the file is executable, run it
302 open(LIN
, "$lsmod_file|");
304 # Just read the contents
305 open(LIN
, "$lsmod_file");
309 # see what modules are loaded on this system
312 foreach my $dir ( ("/sbin", "/bin", "/usr/sbin", "/usr/bin") ) {
313 if ( -x
"$dir/lsmod" ) {
314 $lsmod = "$dir/lsmod";
318 if (!defined($lsmod)) {
323 open(LIN
,"$lsmod|") || die "Can not call lsmod with $lsmod";
327 next if (/^Module/); # Skip the first line.
334 # add to the configs hash all configs that are needed to enable
337 foreach my $module (keys(%modules)) {
338 if (defined($objects{$module})) {
339 my @arr = @
{$objects{$module}};
340 foreach my $conf (@arr) {
341 $configs{$conf} = $module;
344 # Most likely, someone has a custom (binary?) module loaded.
345 print STDERR
"$module config not found!!\n";
349 my $valid = "A-Za-z_0-9";
353 # Note, we do not care about operands (like: &&, ||, !) we want to add any
354 # config that is in the depend list of another config. This script does
355 # not enable configs that are not already enabled. If we come across a
356 # config A that depends on !B, we can still add B to the list of depends
357 # to keep on. If A was on in the original config, B would not have been
358 # and B would not be turned on by this script.
360 sub parse_config_dep_select
364 while ($p =~ /[$valid]/) {
366 if ($p =~ /^[^$valid]*([$valid]+)/) {
367 my $conf = "CONFIG_" . $1;
369 $p =~ s/^[^$valid]*[$valid]+//;
371 if (!defined($configs{$conf})) {
372 # We must make sure that this config has its
374 $repeat = 1; # do again
378 die "this should never happen";
386 foreach my $config (keys %configs) {
387 $config =~ s/^CONFIG_//;
389 if (defined($depends{$config})) {
390 # This config has dependencies. Make sure they are also included
391 parse_config_dep_select
$depends{$config};
394 if (defined($prompts{$config}) || !defined($selects{$config})) {
398 # config has no prompt and must be selected.
399 parse_config_dep_select
$selects{$config};
405 # Finally, read the .config file and turn off any module enabled that
406 # we could not find a reason to keep enabled.
409 if (/CONFIG_IKCONFIG/) {
410 if (/# CONFIG_IKCONFIG is not set/) {
411 # enable IKCONFIG at least as a module
412 print "CONFIG_IKCONFIG=m\n";
413 # don't ask about PROC
414 print "# CONFIG_IKCONFIG_PROC is not set\n";
421 if (/^(CONFIG.*)=(m|y)/) {
422 if (defined($configs{$1})) {
423 $setconfigs{$1} = $2;
424 } elsif ($2 eq "m") {
425 print "# $1 is not set\n";
433 # Integrity check, make sure all modules that we want enabled do
434 # indeed have their configs set.
436 foreach my $module (keys(%modules)) {
437 if (defined($objects{$module})) {
438 my @arr = @
{$objects{$module}};
439 foreach my $conf (@arr) {
440 if (defined($setconfigs{$conf})) {
444 print STDERR
"module $module did not have configs";
445 foreach my $conf (@arr) {
446 print STDERR
" " , $conf;