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
48 # set the environment variable LOCALMODCONFIG_DEBUG to get
51 $debugprint = 1 if (defined($ENV{LOCALMODCONFIG_DEBUG
}));
54 return if (!$debugprint);
58 my $config = ".config";
60 my $uname = `uname -r`;
69 "file" => "/proc/config.gz",
73 "file" => "/boot/config-$uname",
77 "file" => "/boot/vmlinuz-$uname",
78 "exec" => "scripts/extract-ikconfig",
79 "test" => "scripts/extract-ikconfig",
83 "exec" => "scripts/extract-ikconfig",
84 "test" => "scripts/extract-ikconfig",
87 "file" => "/lib/modules/$uname/kernel/kernel/configs.ko",
88 "exec" => "scripts/extract-ikconfig",
89 "test" => "scripts/extract-ikconfig",
92 "file" => "kernel/configs.ko",
93 "exec" => "scripts/extract-ikconfig",
94 "test" => "scripts/extract-ikconfig",
97 "file" => "kernel/configs.o",
98 "exec" => "scripts/extract-ikconfig",
99 "test" => "scripts/extract-ikconfig",
104 foreach my $conf (@searchconfigs) {
105 my $file = $conf->{"file"};
107 next if ( ! -f
"$file");
109 if (defined($conf->{"test"})) {
110 `$conf->{"test"} $conf->{"file"} 2>/dev/null`;
114 my $exec = $conf->{"exec"};
116 print STDERR
"using config: '$file'\n";
118 open(CIN
, "$exec $file |") || die "Failed to run $exec $file";
121 die "No config file found";
126 # Read in the entire config file into config_file
127 my @config_file = <CIN
>;
131 my $localmodconfig = 0;
132 my $localyesconfig = 0;
134 GetOptions
("localmodconfig" => \
$localmodconfig,
135 "localyesconfig" => \
$localyesconfig);
137 # Get the build source and top level Kconfig file (passed in)
138 my $ksource = $ARGV[0];
139 my $kconfig = $ARGV[1];
140 my $lsmod_file = $ENV{'LSMOD'};
142 my @makefiles = `find $ksource -name Makefile 2>/dev/null`;
166 my $source = "$ksource/$kconfig";
167 my $last_source = "";
169 # Check for any environment variables used
170 while ($source =~ /\$(\w+)/ && $last_source ne $source) {
172 $last_source = $source;
173 $source =~ s/\$$env/$ENV{$env}/;
176 open(KIN
, "$source") || die "Can't open $kconfig";
180 # Make sure that lines ending with \ continue
182 $_ = $line . " " . $_;
193 # collect any Kconfig sources
194 if (/^source\s*"(.*)"/) {
195 $kconfigs[$#kconfigs+1] = $1;
199 if (/^\s*(menu)?config\s+(\S+)\s*$/) {
203 # Add depends for 'if' nesting
204 for (my $i = 0; $i < $iflevel; $i++) {
206 $depends{$config} .= " " . $ifdeps[$i];
208 $depends{$config} = $ifdeps[$i];
213 # collect the depends for the config
214 } elsif ($state eq "NEW" && /^\s*depends\s+on\s+(.*)$/) {
216 $depends{$config} = $1;
217 } elsif ($state eq "DEP" && /^\s*depends\s+on\s+(.*)$/) {
218 $depends{$config} .= " " . $1;
220 # Get the configs that select this config
221 } elsif ($state ne "NONE" && /^\s*select\s+(\S+)/) {
223 if (defined($selects{$conf})) {
224 $selects{$conf} .= " " . $config;
226 $selects{$conf} = $config;
229 # configs without prompts must be selected
230 } elsif ($state ne "NONE" && /^\s*tristate\s\S/) {
231 # note if the config has a prompt
232 $prompts{$config} = 1;
234 # Check for if statements
235 } elsif (/^if\s+(.*\S)\s*$/) {
237 # remove beginning and ending non text
238 $deps =~ s/^[^a-zA-Z0-9_]*//;
239 $deps =~ s/[^a-zA-Z0-9_]*$//;
241 my @deps = split /[^a-zA-Z0-9_]+/, $deps;
243 $ifdeps[$iflevel++] = join ':', @deps;
247 $iflevel-- if ($iflevel);
250 } elsif (/^\s*help\s*$/) {
256 # read in any configs that were found.
257 foreach $kconfig (@kconfigs) {
258 if (!defined($read_kconfigs{$kconfig})) {
259 $read_kconfigs{$kconfig} = 1;
260 read_kconfig
($kconfig);
266 read_kconfig
($kconfig);
269 # Makefiles can use variables to define their dependencies
271 my ($line, %vars) = @_;
275 while ($line =~ s/^(.*?)(\$\((.*?)\))//) {
280 if (defined($vars{$var})) {
281 $process .= $start . $vars{$var};
283 $process .= $start . $variable;
292 # Read all Makefiles to map the configs to the objects
293 foreach my $makefile (@makefiles) {
298 open(MIN
,$makefile) || die "Can't open $makefile";
300 # if this line ends with a backslash, continue
313 # Convert variables in a line (could define configs)
314 $_ = convert_vars
($_, %make_vars);
316 # collect objects after obj-$(CONFIG_FOO_BAR)
317 if (/obj-\$\((CONFIG_[^\)]*)\)\s*[+:]?=\s*(.*)/) {
321 # check if variables are set
322 } elsif (/^\s*(\S+)\s*[:]?=\s*(.*\S)/) {
325 if (defined($objs)) {
326 foreach my $obj (split /\s+/,$objs) {
328 if ($obj =~ /(.*)\.o$/) {
329 # Objects may be enabled by more than one config.
330 # Store configs in an array.
333 if (defined($objects{$1})) {
334 @arr = @
{$objects{$1}};
337 $arr[$#arr+1] = $var;
339 # The objects have a hash mapping to a reference
340 # of an array of configs.
341 $objects{$1} = \
@arr;
351 if (defined($lsmod_file)) {
352 if ( ! -f
$lsmod_file) {
353 if ( -f
$ENV{'objtree'}."/".$lsmod_file) {
354 $lsmod_file = $ENV{'objtree'}."/".$lsmod_file;
356 die "$lsmod_file not found";
359 if ( -x
$lsmod_file) {
360 # the file is executable, run it
361 open(LIN
, "$lsmod_file|");
363 # Just read the contents
364 open(LIN
, "$lsmod_file");
368 # see what modules are loaded on this system
371 foreach my $dir ( ("/sbin", "/bin", "/usr/sbin", "/usr/bin") ) {
372 if ( -x
"$dir/lsmod" ) {
373 $lsmod = "$dir/lsmod";
377 if (!defined($lsmod)) {
382 open(LIN
,"$lsmod|") || die "Can not call lsmod with $lsmod";
386 next if (/^Module/); # Skip the first line.
393 # add to the configs hash all configs that are needed to enable
394 # a loaded module. This is a direct obj-${CONFIG_FOO} += bar.o
395 # where we know we need bar.o so we add FOO to the list.
397 foreach my $module (keys(%modules)) {
398 if (defined($objects{$module})) {
399 my @arr = @
{$objects{$module}};
400 foreach my $conf (@arr) {
401 $configs{$conf} = $module;
402 dprint
"$conf added by direct ($module)\n";
405 # Most likely, someone has a custom (binary?) module loaded.
406 print STDERR
"$module config not found!!\n";
410 # Read the current config, and see what is enabled. We want to
411 # ignore configs that we would not enable anyway.
414 my $valid = "A-Za-z_0-9";
416 foreach my $line (@config_file) {
419 if (/(CONFIG_[$valid]*)=(m|y)/) {
420 $orig_configs{$1} = $2;
429 # Note, we do not care about operands (like: &&, ||, !) we want to add any
430 # config that is in the depend list of another config. This script does
431 # not enable configs that are not already enabled. If we come across a
432 # config A that depends on !B, we can still add B to the list of depends
433 # to keep on. If A was on in the original config, B would not have been
434 # and B would not be turned on by this script.
436 sub parse_config_depends
440 while ($p =~ /[$valid]/) {
442 if ($p =~ /^[^$valid]*([$valid]+)/) {
443 my $conf = "CONFIG_" . $1;
445 $p =~ s/^[^$valid]*[$valid]+//;
447 # We only need to process if the depend config is a module
448 if (!defined($orig_configs{$conf}) || !$orig_configs{conf
} eq "m") {
452 if (!defined($configs{$conf})) {
453 # We must make sure that this config has its
455 $repeat = 1; # do again
456 dprint
"$conf selected by depend $depconfig\n";
460 die "this should never happen";
465 # Select is treated a bit differently than depends. We call this
466 # when a config has no prompt and requires another config to be
467 # selected. We use to just select all configs that selected this
468 # config, but found that that can balloon into enabling hundreds
469 # of configs that we do not care about.
471 # The idea is we look at all the configs that select it. If one
472 # is already in our list of configs to enable, then there's nothing
473 # else to do. If there isn't, we pick the first config that was
474 # enabled in the orignal config and use that.
475 sub parse_config_selects
477 my ($config, $p) = @_;
481 while ($p =~ /[$valid]/) {
483 if ($p =~ /^[^$valid]*([$valid]+)/) {
484 my $conf = "CONFIG_" . $1;
486 $p =~ s/^[^$valid]*[$valid]+//;
488 # Make sure that this config exists in the current .config file
489 if (!defined($orig_configs{$conf})) {
490 dprint
"$conf not set for $config select\n";
494 # Check if something other than a module selects this config
495 if (defined($orig_configs{$conf}) && $orig_configs{$conf} ne "m") {
496 dprint
"$conf (non module) selects config, we are good\n";
497 # we are good with this
500 if (defined($configs{$conf})) {
501 dprint
"$conf selects $config so we are good\n";
502 # A set config selects this config, we are good
505 # Set this config to be selected
506 if (!defined($next_config)) {
507 $next_config = $conf;
510 die "this should never happen";
514 # If no possible config selected this, then something happened.
515 if (!defined($next_config)) {
516 print STDERR
"WARNING: $config is required, but nothing in the\n";
517 print STDERR
" current config selects it.\n";
521 # If we are here, then we found no config that is set and
522 # selects this config. Repeat.
524 # Make this config need to be selected
525 $configs{$next_config} = 1;
526 dprint
"$next_config selected by select $config\n";
531 # loop through all configs, select their dependencies.
539 foreach my $config (keys %configs) {
541 # If this config is not a module, we do not need to process it
542 if (defined($orig_configs{$config}) && $orig_configs{$config} ne "m") {
546 $config =~ s/^CONFIG_//;
547 $depconfig = $config;
549 if (defined($depends{$config})) {
550 # This config has dependencies. Make sure they are also included
551 parse_config_depends
$depends{$config};
554 # If the config has no prompt, then we need to check if a config
555 # that is enabled selected it. Or if we need to enable one.
556 if (!defined($prompts{$config}) && defined($selects{$config})) {
557 $process_selects{$config} = 1;
565 foreach my $config (keys %process_selects) {
566 $config =~ s/^CONFIG_//;
568 dprint
"Process select $config\n";
570 # config has no prompt and must be selected.
571 parse_config_selects
$config, $selects{$config};
576 # Get the first set of configs and their dependencies.
581 # Now we need to see if we have to check selects;
587 # Finally, read the .config file and turn off any module enabled that
588 # we could not find a reason to keep enabled.
589 foreach my $line (@config_file) {
592 if (/CONFIG_IKCONFIG/) {
593 if (/# CONFIG_IKCONFIG is not set/) {
594 # enable IKCONFIG at least as a module
595 print "CONFIG_IKCONFIG=m\n";
596 # don't ask about PROC
597 print "# CONFIG_IKCONFIG_PROC is not set\n";
604 if (/^(CONFIG.*)=(m|y)/) {
605 if (defined($configs{$1})) {
606 if ($localyesconfig) {
607 $setconfigs{$1} = 'y';
609 $setconfigs{$1} = $2;
611 } elsif ($2 eq "m") {
612 print "# $1 is not set\n";
619 # Integrity check, make sure all modules that we want enabled do
620 # indeed have their configs set.
622 foreach my $module (keys(%modules)) {
623 if (defined($objects{$module})) {
624 my @arr = @
{$objects{$module}};
625 foreach my $conf (@arr) {
626 if (defined($setconfigs{$conf})) {
630 print STDERR
"module $module did not have configs";
631 foreach my $conf (@arr) {
632 print STDERR
" " , $conf;