linux/scripts/kconfig/streamline_config.pl
<<
>>
Prefs
   1#!/usr/bin/perl -w
   2#
   3# Copywrite 2005-2009 - Steven Rostedt
   4# Licensed under the terms of the GNU GPL License version 2
   5#
   6#  It's simple enough to figure out how this works.
   7#  If not, then you can ask me at stripconfig@goodmis.org
   8#
   9# What it does?
  10#
  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
  14#   is perfect for you.
  15#
  16#   It gives you the ability to turn off all the modules that are
  17#   not loaded on your system.
  18#
  19# Howto:
  20#
  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
  28#       like config_strip.
  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"
  32#
  33#  Now your kernel is ready to be built with only the modules that
  34#  are loaded.
  35#
  36# Here's what I did with my Debian distribution.
  37#
  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
  43#    make oldconfig
  44#
  45my $config = ".config";
  46
  47my $uname = `uname -r`;
  48chomp $uname;
  49
  50my @searchconfigs = (
  51        {
  52            "file" => ".config",
  53            "exec" => "cat",
  54        },
  55        {
  56            "file" => "/proc/config.gz",
  57            "exec" => "zcat",
  58        },
  59        {
  60            "file" => "/boot/config-$uname",
  61            "exec" => "cat",
  62        },
  63        {
  64            "file" => "/boot/vmlinuz-$uname",
  65            "exec" => "scripts/extract-ikconfig",
  66            "test" => "scripts/extract-ikconfig",
  67        },
  68        {
  69            "file" => "vmlinux",
  70            "exec" => "scripts/extract-ikconfig",
  71            "test" => "scripts/extract-ikconfig",
  72        },
  73        {
  74            "file" => "/lib/modules/$uname/kernel/kernel/configs.ko",
  75            "exec" => "scripts/extract-ikconfig",
  76            "test" => "scripts/extract-ikconfig",
  77        },
  78        {
  79            "file" => "kernel/configs.ko",
  80            "exec" => "scripts/extract-ikconfig",
  81            "test" => "scripts/extract-ikconfig",
  82        },
  83        {
  84            "file" => "kernel/configs.o",
  85            "exec" => "scripts/extract-ikconfig",
  86            "test" => "scripts/extract-ikconfig",
  87        },
  88);
  89
  90sub find_config {
  91    foreach my $conf (@searchconfigs) {
  92        my $file = $conf->{"file"};
  93
  94        next if ( ! -f "$file");
  95
  96        if (defined($conf->{"test"})) {
  97            `$conf->{"test"} $conf->{"file"} 2>/dev/null`;
  98            next if ($?);
  99        }
 100
 101        my $exec = $conf->{"exec"};
 102
 103        print STDERR "using config: '$file'\n";
 104
 105        open(CIN, "$exec $file |") || die "Failed to run $exec $file";
 106        return;
 107    }
 108    die "No config file found";
 109}
 110
 111find_config;
 112
 113# Get the build source and top level Kconfig file (passed in)
 114my $ksource = $ARGV[0];
 115my $kconfig = $ARGV[1];
 116my $lsmod_file = $ARGV[2];
 117
 118my @makefiles = `find $ksource -name Makefile 2>/dev/null`;
 119chomp @makefiles;
 120
 121my %depends;
 122my %selects;
 123my %prompts;
 124my %objects;
 125my $var;
 126my $cont = 0;
 127my $iflevel = 0;
 128my @ifdeps;
 129
 130# prevent recursion
 131my %read_kconfigs;
 132
 133sub read_kconfig {
 134    my ($kconfig) = @_;
 135
 136    my $state = "NONE";
 137    my $config;
 138    my @kconfigs;
 139
 140    open(KIN, "$ksource/$kconfig") || die "Can't open $kconfig";
 141    while (<KIN>) {
 142        chomp;
 143
 144        # collect any Kconfig sources
 145        if (/^source\s*"(.*)"/) {
 146            $kconfigs[$#kconfigs+1] = $1;
 147        }
 148
 149        # configs found
 150        if (/^\s*config\s+(\S+)\s*$/) {
 151            $state = "NEW";
 152            $config = $1;
 153
 154            for (my $i = 0; $i < $iflevel; $i++) {
 155                if ($i) {
 156                    $depends{$config} .= " " . $ifdeps[$i];
 157                } else {
 158                    $depends{$config} = $ifdeps[$i];
 159                }
 160                $state = "DEP";
 161            }
 162
 163        # collect the depends for the config
 164        } elsif ($state eq "NEW" && /^\s*depends\s+on\s+(.*)$/) {
 165            $state = "DEP";
 166            $depends{$config} = $1;
 167        } elsif ($state eq "DEP" && /^\s*depends\s+on\s+(.*)$/) {
 168            $depends{$config} .= " " . $1;
 169
 170        # Get the configs that select this config
 171        } elsif ($state ne "NONE" && /^\s*select\s+(\S+)/) {
 172            if (defined($selects{$1})) {
 173                $selects{$1} .= " " . $config;
 174            } else {
 175                $selects{$1} = $config;
 176            }
 177
 178        # configs without prompts must be selected
 179        } elsif ($state ne "NONE" && /^\s*tristate\s\S/) {
 180            # note if the config has a prompt
 181            $prompt{$config} = 1;
 182
 183        # Check for if statements
 184        } elsif (/^if\s+(.*\S)\s*$/) {
 185            my $deps = $1;
 186            # remove beginning and ending non text
 187            $deps =~ s/^[^a-zA-Z0-9_]*//;
 188            $deps =~ s/[^a-zA-Z0-9_]*$//;
 189
 190            my @deps = split /[^a-zA-Z0-9_]+/, $deps;
 191
 192            $ifdeps[$iflevel++] = join ':', @deps;
 193
 194        } elsif (/^endif/) {
 195
 196            $iflevel-- if ($iflevel);
 197
 198        # stop on "help"
 199        } elsif (/^\s*help\s*$/) {
 200            $state = "NONE";
 201        }
 202    }
 203    close(KIN);
 204
 205    # read in any configs that were found.
 206    foreach $kconfig (@kconfigs) {
 207        if (!defined($read_kconfigs{$kconfig})) {
 208            $read_kconfigs{$kconfig} = 1;
 209            read_kconfig($kconfig);
 210        }
 211    }
 212}
 213
 214if ($kconfig) {
 215    read_kconfig($kconfig);
 216}
 217
 218# Read all Makefiles to map the configs to the objects
 219foreach my $makefile (@makefiles) {
 220
 221    open(MIN,$makefile) || die "Can't open $makefile";
 222    while (<MIN>) {
 223        my $objs;
 224
 225        # is this a line after a line with a backslash?
 226        if ($cont && /(\S.*)$/) {
 227            $objs = $1;
 228        }
 229        $cont = 0;
 230
 231        # collect objects after obj-$(CONFIG_FOO_BAR)
 232        if (/obj-\$\((CONFIG_[^\)]*)\)\s*[+:]?=\s*(.*)/) {
 233            $var = $1;
 234            $objs = $2;
 235        }
 236        if (defined($objs)) {
 237            # test if the line ends with a backslash
 238            if ($objs =~ m,(.*)\\$,) {
 239                $objs = $1;
 240                $cont = 1;
 241            }
 242
 243            foreach my $obj (split /\s+/,$objs) {
 244                $obj =~ s/-/_/g;
 245                if ($obj =~ /(.*)\.o$/) {
 246                    # Objects may be enabled by more than one config.
 247                    # Store configs in an array.
 248                    my @arr;
 249
 250                    if (defined($objects{$1})) {
 251                        @arr = @{$objects{$1}};
 252                    }
 253
 254                    $arr[$#arr+1] = $var;
 255
 256                    # The objects have a hash mapping to a reference
 257                    # of an array of configs.
 258                    $objects{$1} = \@arr;
 259                }
 260            }
 261        }
 262    }
 263    close(MIN);
 264}
 265
 266my %modules;
 267
 268if (defined($lsmod_file)) {
 269    if ( ! -f $lsmod_file) {
 270        die "$lsmod_file not found";
 271    }
 272    if ( -x $lsmod_file) {
 273        # the file is executable, run it
 274        open(LIN, "$lsmod_file|");
 275    } else {
 276        # Just read the contents
 277        open(LIN, "$lsmod_file");
 278    }
 279} else {
 280
 281    # see what modules are loaded on this system
 282    my $lsmod;
 283
 284    foreach $dir ( ("/sbin", "/bin", "/usr/sbin", "/usr/bin") ) {
 285        if ( -x "$dir/lsmod" ) {
 286            $lsmod = "$dir/lsmod";
 287            last;
 288        }
 289}
 290    if (!defined($lsmod)) {
 291        # try just the path
 292        $lsmod = "lsmod";
 293    }
 294
 295    open(LIN,"$lsmod|") || die "Can not call lsmod with $lsmod";
 296}
 297
 298while (<LIN>) {
 299        next if (/^Module/);  # Skip the first line.
 300        if (/^(\S+)/) {
 301                $modules{$1} = 1;
 302        }
 303}
 304close (LIN);
 305
 306# add to the configs hash all configs that are needed to enable
 307# a loaded module.
 308my %configs;
 309foreach my $module (keys(%modules)) {
 310    if (defined($objects{$module})) {
 311        my @arr = @{$objects{$module}};
 312        foreach my $conf (@arr) {
 313            $configs{$conf} = $module;
 314        }
 315    } else {
 316        # Most likely, someone has a custom (binary?) module loaded.
 317        print STDERR "$module config not found!!\n";
 318    }
 319}
 320
 321my $valid = "A-Za-z_0-9";
 322my $repeat = 1;
 323
 324#
 325# Note, we do not care about operands (like: &&, ||, !) we want to add any
 326# config that is in the depend list of another config. This script does
 327# not enable configs that are not already enabled. If we come across a
 328# config A that depends on !B, we can still add B to the list of depends
 329# to keep on. If A was on in the original config, B would not have been
 330# and B would not be turned on by this script.
 331#
 332sub parse_config_dep_select
 333{
 334    my ($p) = @_;
 335
 336    while ($p =~ /[$valid]/) {
 337
 338        if ($p =~ /^[^$valid]*([$valid]+)/) {
 339            my $conf = "CONFIG_" . $1;
 340
 341            $p =~ s/^[^$valid]*[$valid]+//;
 342
 343            if (!defined($configs{$conf})) {
 344                # We must make sure that this config has its
 345                # dependencies met.
 346                $repeat = 1; # do again
 347                $configs{$conf} = 1;
 348            }
 349        } else {
 350            die "this should never happen";
 351        }
 352    }
 353}
 354
 355while ($repeat) {
 356    $repeat = 0;
 357
 358    foreach my $config (keys %configs) {
 359        $config =~ s/^CONFIG_//;
 360
 361        if (defined($depends{$config})) {
 362            # This config has dependencies. Make sure they are also included
 363            parse_config_dep_select $depends{$config};
 364        }
 365
 366        if (defined($prompt{$config}) || !defined($selects{$config})) {
 367            next;
 368        }
 369
 370        # config has no prompt and must be selected.
 371        parse_config_dep_select $selects{$config};
 372    }
 373}
 374
 375my %setconfigs;
 376
 377# Finally, read the .config file and turn off any module enabled that
 378# we could not find a reason to keep enabled.
 379while(<CIN>) {
 380
 381    if (/CONFIG_IKCONFIG/) {
 382        if (/# CONFIG_IKCONFIG is not set/) {
 383            # enable IKCONFIG at least as a module
 384            print "CONFIG_IKCONFIG=m\n";
 385            # don't ask about PROC
 386            print "# CONFIG_IKCONFIG_PROC is not set\n";
 387        } else {
 388            print;
 389        }
 390        next;
 391    }
 392
 393    if (/^(CONFIG.*)=(m|y)/) {
 394        if (defined($configs{$1})) {
 395            $setconfigs{$1} = $2;
 396        } elsif ($2 eq "m") {
 397            print "# $1 is not set\n";
 398            next;
 399        }
 400    }
 401    print;
 402}
 403close(CIN);
 404
 405# Integrity check, make sure all modules that we want enabled do
 406# indeed have their configs set.
 407loop:
 408foreach my $module (keys(%modules)) {
 409    if (defined($objects{$module})) {
 410        my @arr = @{$objects{$module}};
 411        foreach my $conf (@arr) {
 412            if (defined($setconfigs{$conf})) {
 413                next loop;
 414            }
 415        }
 416        print STDERR "module $module did not have configs";
 417        foreach my $conf (@arr) {
 418            print STDERR " " , $conf;
 419        }
 420        print STDERR "\n";
 421    }
 422}
 423