scripts/kconfig/streamline_config.pl

   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 #
  45 use strict;
  46
  47 my $config = ".config";
  48
  49 my $uname = `uname -r`;
  50 chomp $uname;
  51
  52 my @searchconfigs = (
  53         {
  54             "file" => ".config",
  55             "exec" => "cat",
  56         },
  57         {
  58             "file" => "/proc/config.gz",
  59             "exec" => "zcat",
  60         },
  61         {
  62             "file" => "/boot/config-$uname",
  63             "exec" => "cat",
  64         },
  65         {
  66             "file" => "/boot/vmlinuz-$uname",
  67             "exec" => "scripts/extract-ikconfig",
  68             "test" => "scripts/extract-ikconfig",
  69         },
  70         {
  71             "file" => "vmlinux",
  72             "exec" => "scripts/extract-ikconfig",
  73             "test" => "scripts/extract-ikconfig",
  74         },
  75         {
  76             "file" => "/lib/modules/$uname/kernel/kernel/configs.ko",
  77             "exec" => "scripts/extract-ikconfig",
  78             "test" => "scripts/extract-ikconfig",
  79         },
  80         {
  81             "file" => "kernel/configs.ko",
  82             "exec" => "scripts/extract-ikconfig",
  83             "test" => "scripts/extract-ikconfig",
  84         },
  85         {
  86             "file" => "kernel/configs.o",
  87             "exec" => "scripts/extract-ikconfig",
  88             "test" => "scripts/extract-ikconfig",
  89         },
  90 );
  91
  92 sub find_config {
  93     foreach my $conf (@searchconfigs) {
  94         my $file = $conf->{"file"};
  95
  96         next if ( ! -f "$file");
  97
  98         if (defined($conf->{"test"})) {
  99             `$conf->{"test"} $conf->{"file"} 2>/dev/null`;
 100             next if ($?);
 101         }
 102
 103         my $exec = $conf->{"exec"};
 104
 105         print STDERR "using config: '$file'\n";
 106
 107         open(CIN, "$exec $file |") || die "Failed to run $exec $file";
 108         return;
 109     }
 110     die "No config file found";
 111 }
 112
 113 find_config;
 114
 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];
 119
 120 my @makefiles = `find $ksource -name Makefile 2>/dev/null`;
 121 chomp @makefiles;
 122
 123 my %depends;
 124 my %selects;
 125 my %prompts;
 126 my %objects;
 127 my $var;
 128 my $iflevel = 0;
 129 my @ifdeps;
 130
 131 # prevent recursion
 132 my %read_kconfigs;
 133
 134 sub read_kconfig {
 135     my ($kconfig) = @_;
 136
 137     my $state = "NONE";
 138     my $config;
 139     my @kconfigs;
 140
 141     my $cont = 0;
 142     my $line;
 143
 144     my $source = "$ksource/$kconfig";
 145     my $last_source = "";
 146
 147     # Check for any environment variables used
 148     while ($source =~ /\$(\w+)/ && $last_source ne $source) {
 149         my $env = $1;
 150         $last_source = $source;
 151         $source =~ s/\$$env/$ENV{$env}/;
 152     }
 153
 154     open(KIN, "$source") || die "Can't open $kconfig";
 155     while (<KIN>) {
 156         chomp;
 157
 158         # Make sure that lines ending with \ continue
 159         if ($cont) {
 160             $_ = $line . " " . $_;
 161         }
 162
 163         if (s/\\$//) {
 164             $cont = 1;
 165             $line = $_;
 166             next;
 167         }
 168
 169         $cont = 0;
 170
 171         # collect any Kconfig sources
 172         if (/^source\s*"(.*)"/) {
 173             $kconfigs[$#kconfigs+1] = $1;
 174         }
 175
 176         # configs found
 177         if (/^\s*(menu)?config\s+(\S+)\s*$/) {
 178             $state = "NEW";
 179             $config = $2;
 180
 181             for (my $i = 0; $i < $iflevel; $i++) {
 182                 if ($i) {
 183                     $depends{$config} .= " " . $ifdeps[$i];
 184                 } else {
 185                     $depends{$config} = $ifdeps[$i];
 186                 }
 187                 $state = "DEP";
 188             }
 189
 190         # collect the depends for the config
 191         } elsif ($state eq "NEW" && /^\s*depends\s+on\s+(.*)$/) {
 192             $state = "DEP";
 193             $depends{$config} = $1;
 194         } elsif ($state eq "DEP" && /^\s*depends\s+on\s+(.*)$/) {
 195             $depends{$config} .= " " . $1;
 196
 197         # Get the configs that select this config
 198         } elsif ($state ne "NONE" && /^\s*select\s+(\S+)/) {
 199             if (defined($selects{$1})) {
 200                 $selects{$1} .= " " . $config;
 201             } else {
 202                 $selects{$1} = $config;
 203             }
 204
 205         # configs without prompts must be selected
 206         } elsif ($state ne "NONE" && /^\s*tristate\s\S/) {
 207             # note if the config has a prompt
 208             $prompts{$config} = 1;
 209
 210         # Check for if statements
 211         } elsif (/^if\s+(.*\S)\s*$/) {
 212             my $deps = $1;
 213             # remove beginning and ending non text
 214             $deps =~ s/^[^a-zA-Z0-9_]*//;
 215             $deps =~ s/[^a-zA-Z0-9_]*$//;
 216
 217             my @deps = split /[^a-zA-Z0-9_]+/, $deps;
 218
 219             $ifdeps[$iflevel++] = join ':', @deps;
 220
 221         } elsif (/^endif/) {
 222
 223             $iflevel-- if ($iflevel);
 224
 225         # stop on "help"
 226         } elsif (/^\s*help\s*$/) {
 227             $state = "NONE";
 228         }
 229     }
 230     close(KIN);
 231
 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($kconfig);
 237         }
 238     }
 239 }
 240
 241 if ($kconfig) {
 242     read_kconfig($kconfig);
 243 }
 244
 245 # Read all Makefiles to map the configs to the objects
 246 foreach my $makefile (@makefiles) {
 247
 248     my $cont = 0;
 249
 250     open(MIN,$makefile) || die "Can't open $makefile";
 251     while (<MIN>) {
 252         my $objs;
 253
 254         # is this a line after a line with a backslash?
 255         if ($cont && /(\S.*)$/) {
 256             $objs = $1;
 257         }
 258         $cont = 0;
 259
 260         # collect objects after obj-$(CONFIG_FOO_BAR)
 261         if (/obj-\$\((CONFIG_[^\)]*)\)\s*[+:]?=\s*(.*)/) {
 262             $var = $1;
 263             $objs = $2;
 264         }
 265         if (defined($objs)) {
 266             # test if the line ends with a backslash
 267             if ($objs =~ m,(.*)\\$,) {
 268                 $objs = $1;
 269                 $cont = 1;
 270             }
 271
 272             foreach my $obj (split /\s+/,$objs) {
 273                 $obj =~ s/-/_/g;
 274                 if ($obj =~ /(.*)\.o$/) {
 275                     # Objects may be enabled by more than one config.
 276                     # Store configs in an array.
 277                     my @arr;
 278
 279                     if (defined($objects{$1})) {
 280                         @arr = @{$objects{$1}};
 281                     }
 282
 283                     $arr[$#arr+1] = $var;
 284
 285                     # The objects have a hash mapping to a reference
 286                     # of an array of configs.
 287                     $objects{$1} = \@arr;
 288                 }
 289             }
 290         }
 291     }
 292     close(MIN);
 293 }
 294
 295 my %modules;
 296
 297 if (defined($lsmod_file)) {
 298     if ( ! -f $lsmod_file) {
 299         die "$lsmod_file not found";
 300     }
 301     if ( -x $lsmod_file) {
 302         # the file is executable, run it
 303         open(LIN, "$lsmod_file|");
 304     } else {
 305         # Just read the contents
 306         open(LIN, "$lsmod_file");
 307     }
 308 } else {
 309
 310     # see what modules are loaded on this system
 311     my $lsmod;
 312
 313     foreach my $dir ( ("/sbin", "/bin", "/usr/sbin", "/usr/bin") ) {
 314         if ( -x "$dir/lsmod" ) {
 315             $lsmod = "$dir/lsmod";
 316             last;
 317         }
 318 }
 319     if (!defined($lsmod)) {
 320         # try just the path
 321         $lsmod = "lsmod";
 322     }
 323
 324     open(LIN,"$lsmod|") || die "Can not call lsmod with $lsmod";
 325 }
 326
 327 while (<LIN>) {
 328         next if (/^Module/);  # Skip the first line.
 329         if (/^(\S+)/) {
 330                 $modules{$1} = 1;
 331         }
 332 }
 333 close (LIN);
 334
 335 # add to the configs hash all configs that are needed to enable
 336 # a loaded module.
 337 my %configs;
 338 foreach my $module (keys(%modules)) {
 339     if (defined($objects{$module})) {
 340         my @arr = @{$objects{$module}};
 341         foreach my $conf (@arr) {
 342             $configs{$conf} = $module;
 343         }
 344     } else {
 345         # Most likely, someone has a custom (binary?) module loaded.
 346         print STDERR "$module config not found!!\n";
 347     }
 348 }
 349
 350 my $valid = "A-Za-z_0-9";
 351 my $repeat = 1;
 352
 353 #
 354 # Note, we do not care about operands (like: &&, ||, !) we want to add any
 355 # config that is in the depend list of another config. This script does
 356 # not enable configs that are not already enabled. If we come across a
 357 # config A that depends on !B, we can still add B to the list of depends
 358 # to keep on. If A was on in the original config, B would not have been
 359 # and B would not be turned on by this script.
 360 #
 361 sub parse_config_dep_select
 362 {
 363     my ($p) = @_;
 364
 365     while ($p =~ /[$valid]/) {
 366
 367         if ($p =~ /^[^$valid]*([$valid]+)/) {
 368             my $conf = "CONFIG_" . $1;
 369
 370             $p =~ s/^[^$valid]*[$valid]+//;
 371
 372             if (!defined($configs{$conf})) {
 373                 # We must make sure that this config has its
 374                 # dependencies met.
 375                 $repeat = 1; # do again
 376                 $configs{$conf} = 1;
 377             }
 378         } else {
 379             die "this should never happen";
 380         }
 381     }
 382 }
 383
 384 while ($repeat) {
 385     $repeat = 0;
 386
 387     foreach my $config (keys %configs) {
 388         $config =~ s/^CONFIG_//;
 389
 390         if (defined($depends{$config})) {
 391             # This config has dependencies. Make sure they are also included
 392             parse_config_dep_select $depends{$config};
 393         }
 394
 395         if (defined($prompts{$config}) || !defined($selects{$config})) {
 396             next;
 397         }
 398
 399         # config has no prompt and must be selected.
 400         parse_config_dep_select $selects{$config};
 401     }
 402 }
 403
 404 my %setconfigs;
 405
 406 # Finally, read the .config file and turn off any module enabled that
 407 # we could not find a reason to keep enabled.
 408 while(<CIN>) {
 409
 410     if (/CONFIG_IKCONFIG/) {
 411         if (/# CONFIG_IKCONFIG is not set/) {
 412             # enable IKCONFIG at least as a module
 413             print "CONFIG_IKCONFIG=m\n";
 414             # don't ask about PROC
 415             print "# CONFIG_IKCONFIG_PROC is not set\n";
 416         } else {
 417             print;
 418         }
 419         next;
 420     }
 421
 422     if (/^(CONFIG.*)=(m|y)/) {
 423         if (defined($configs{$1})) {
 424             $setconfigs{$1} = $2;
 425         } elsif ($2 eq "m") {
 426             print "# $1 is not set\n";
 427             next;
 428         }
 429     }
 430     print;
 431 }
 432 close(CIN);
 433
 434 # Integrity check, make sure all modules that we want enabled do
 435 # indeed have their configs set.
 436 loop:
 437 foreach my $module (keys(%modules)) {
 438     if (defined($objects{$module})) {
 439         my @arr = @{$objects{$module}};
 440         foreach my $conf (@arr) {
 441             if (defined($setconfigs{$conf})) {
 442                 next loop;
 443             }
 444         }
 445         print STDERR "module $module did not have configs";
 446         foreach my $conf (@arr) {
 447             print STDERR " " , $conf;
 448         }
 449         print STDERR "\n";
 450     }
 451 }