3 # Copywrite 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
45 my $config = ".config";
47 my $uname = `uname -r`;
56 "file" => "/proc/config.gz",
60 "file" => "/boot/config-$uname",
64 "file" => "/boot/vmlinuz-$uname",
65 "exec" => "scripts/extract-ikconfig",
66 "test" => "scripts/extract-ikconfig",
70 "exec" => "scripts/extract-ikconfig",
71 "test" => "scripts/extract-ikconfig",
74 "file" => "/lib/modules/$uname/kernel/kernel/configs.ko",
75 "exec" => "scripts/extract-ikconfig",
76 "test" => "scripts/extract-ikconfig",
79 "file" => "kernel/configs.ko",
80 "exec" => "scripts/extract-ikconfig",
81 "test" => "scripts/extract-ikconfig",
84 "file" => "kernel/configs.o",
85 "exec" => "scripts/extract-ikconfig",
86 "test" => "scripts/extract-ikconfig",
91 foreach my $conf (@searchconfigs) {
92 my $file = $conf->{"file"};
94 next if ( ! -f "$file");
96 if (defined($conf->{"test"})) {
97 `$conf->{"test"} $conf->{"file"} 2>/dev/null`;
101 my $exec = $conf->{"exec"};
103 print STDERR "using config: '$file'\n";
105 open(CIN, "$exec $file |") || die "Failed to run $exec $file";
108 die "No config file found";
113 # Get the build source and top level Kconfig file (passed in)
114 my $ksource = $ARGV[0];
115 my $kconfig = $ARGV[1];
117 my @makefiles = `find $ksource -name Makefile`;
137 open(KIN, "$ksource/$kconfig") || die "Can't open $kconfig";
141 # collect any Kconfig sources
142 if (/^source\s*"(.*)"/) {
143 $kconfigs[$#kconfigs+1] = $1;
147 if (/^\s*config\s+(\S+)\s*$/) {
151 for (my $i = 0; $i < $iflevel; $i++) {
153 $depends{$config} .= " " . $ifdeps[$i];
155 $depends{$config} = $ifdeps[$i];
160 # collect the depends for the config
161 } elsif ($state eq "NEW" && /^\s*depends\s+on\s+(.*)$/) {
163 $depends{$config} = $1;
164 } elsif ($state eq "DEP" && /^\s*depends\s+on\s+(.*)$/) {
165 $depends{$config} .= " " . $1;
167 # Get the configs that select this config
168 } elsif ($state ne "NONE" && /^\s*select\s+(\S+)/) {
169 if (defined($selects{$1})) {
170 $selects{$1} .= " " . $config;
172 $selects{$1} = $config;
175 # configs without prompts must be selected
176 } elsif ($state ne "NONE" && /^\s*tristate\s\S/) {
177 # note if the config has a prompt
178 $prompt{$config} = 1;
180 # Check for if statements
181 } elsif (/^if\s+(.*\S)\s*$/) {
183 # remove beginning and ending non text
184 $deps =~ s/^[^a-zA-Z0-9_]*//;
185 $deps =~ s/[^a-zA-Z0-9_]*$//;
187 my @deps = split /[^a-zA-Z0-9_]+/, $deps;
189 $ifdeps[$iflevel++] = join ':', @deps;
193 $iflevel-- if ($iflevel);
196 } elsif (/^\s*help\s*$/) {
202 # read in any configs that were found.
203 foreach $kconfig (@kconfigs) {
204 if (!defined($read_kconfigs{$kconfig})) {
205 $read_kconfigs{$kconfig} = 1;
206 read_kconfig($kconfig);
212 read_kconfig($kconfig);
215 # Read all Makefiles to map the configs to the objects
216 foreach my $makefile (@makefiles) {
219 open(MIN,$makefile) || die "Can't open $makefile";
223 # is this a line after a line with a backslash?
224 if ($cont && /(\S.*)$/) {
229 # collect objects after obj-$(CONFIG_FOO_BAR)
230 if (/obj-\$\((CONFIG_[^\)]*)\)\s*[+:]?=\s*(.*)/) {
234 if (defined($objs)) {
235 # test if the line ends with a backslash
236 if ($objs =~ m,(.*)\\$,) {
241 foreach my $obj (split /\s+/,$objs) {
243 if ($obj =~ /(.*)\.o$/) {
244 # Objects may bes enabled by more than one config.
245 # Store configs in an array.
248 if (defined($objects{$1})) {
249 @arr = @{$objects{$1}};
252 $arr[$#arr+1] = $var;
254 # The objects have a hash mapping to a reference
255 # of an array of configs.
256 $objects{$1} = \@arr;
266 # see what modules are loaded on this system
269 foreach $dir ( ("/sbin", "/bin", "/usr/sbin", "/usr/bin") ) {
270 if ( -x "$dir/lsmod" ) {
271 $lsmod = "$dir/lsmod";
275 if (!defined($lsmod)) {
280 open(LIN,"$lsmod|") || die "Can not call lsmod with $lsmod";
282 next if (/^Module/); # Skip the first line.
289 # add to the configs hash all configs that are needed to enable
292 foreach my $module (keys(%modules)) {
293 if (defined($objects{$module})) {
294 @arr = @{$objects{$module}};
295 foreach my $conf (@arr) {
296 $configs{$conf} = $module;
299 # Most likely, someone has a custom (binary?) module loaded.
300 print STDERR "$module config not found!!\n";
304 my $valid = "A-Za-z_0-9";
308 # Note, we do not care about operands (like: &&, ||, !) we want to add any
309 # config that is in the depend list of another config. This script does
310 # not enable configs that are not already enabled. If we come across a
311 # config A that depends on !B, we can still add B to the list of depends
312 # to keep on. If A was on in the original config, B would not have been
313 # and B would not be turned on by this script.
315 sub parse_config_dep_select
319 while ($p =~ /[$valid]/) {
321 if ($p =~ /^[^$valid]*([$valid]+)/) {
322 my $conf = "CONFIG_" . $1;
324 $p =~ s/^[^$valid]*[$valid]+//;
326 if (!defined($configs{$conf})) {
327 # We must make sure that this config has its
329 $repeat = 1; # do again
333 die "this should never happen";
341 foreach my $config (keys %configs) {
342 $config =~ s/^CONFIG_//;
344 if (defined($depends{$config})) {
345 # This config has dependencies. Make sure they are also included
346 parse_config_dep_select $depends{$config};
349 if (defined($prompt{$config}) || !defined($selects{$config})) {
353 # config has no prompt and must be selected.
354 parse_config_dep_select $selects{$config};
360 # Finally, read the .config file and turn off any module enabled that
361 # we could not find a reason to keep enabled.
364 if (/CONFIG_IKCONFIG/) {
365 if (/# CONFIG_IKCONFIG is not set/) {
366 # enable IKCONFIG at least as a module
367 print "CONFIG_IKCONFIG=m\n";
368 # don't ask about PROC
369 print "# CONFIG_IKCONFIG_PROC is not set\n";
376 if (/^(CONFIG.*)=(m|y)/) {
377 if (defined($configs{$1})) {
378 $setconfigs{$1} = $2;
379 } elsif ($2 eq "m") {
380 print "# $1 is not set\n";
388 # Integrity check, make sure all modules that we want enabled do
389 # indeed have their configs set.
391 foreach my $module (keys(%modules)) {
392 if (defined($objects{$module})) {
393 my @arr = @{$objects{$module}};
394 foreach my $conf (@arr) {
395 if (defined($setconfigs{$conf})) {
399 print STDERR "module $module did not have configs";
400 foreach my $conf (@arr) {
401 print STDERR " " , $conf;