summaryrefslogtreecommitdiffstats
path: root/scripts/kconfig/streamline_config.pl
blob: f3d3fb42b8735e76aa54bd4c433574f7afc43b0e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
#!/usr/bin/perl -w
#
# Copyright 2005-2009 - Steven Rostedt
# Licensed under the terms of the GNU GPL License version 2
#
#  It's simple enough to figure out how this works.
#  If not, then you can ask me at stripconfig@goodmis.org
#
# What it does?
#
#   If you have installed a Linux kernel from a distribution
#   that turns on way too many modules than you need, and
#   you only want the modules you use, then this program
#   is perfect for you.
#
#   It gives you the ability to turn off all the modules that are
#   not loaded on your system.
#
# Howto:
#
#  1. Boot up the kernel that you want to stream line the config on.
#  2. Change directory to the directory holding the source of the
#       kernel that you just booted.
#  3. Copy the configuraton file to this directory as .config
#  4. Have all your devices that you need modules for connected and
#      operational (make sure that their corresponding modules are loaded)
#  5. Run this script redirecting the output to some other file
#       like config_strip.
#  6. Back up your old config (if you want too).
#  7. copy the config_strip file to .config
#  8. Run "make oldconfig"
#
#  Now your kernel is ready to be built with only the modules that
#  are loaded.
#
# Here's what I did with my Debian distribution.
#
#    cd /usr/src/linux-2.6.10
#    cp /boot/config-2.6.10-1-686-smp .config
#    ~/bin/streamline_config > config_strip
#    mv .config config_sav
#    mv config_strip .config
#    make oldconfig
#
use strict;
use Getopt::Long;

# set the environment variable LOCALMODCONFIG_DEBUG to get
# debug output.
my $debugprint = 0;
$debugprint = 1 if (defined($ENV{LOCALMODCONFIG_DEBUG}));

sub dprint {
    return if (!$debugprint);
    print STDERR @_;
}

my $config = ".config";

my $uname = `uname -r`;
chomp $uname;

my @searchconfigs = (
	{
	    "file" => ".config",
	    "exec" => "cat",
	},
	{
	    "file" => "/proc/config.gz",
	    "exec" => "zcat",
	},
	{
	    "file" => "/boot/config-$uname",
	    "exec" => "cat",
	},
	{
	    "file" => "/boot/vmlinuz-$uname",
	    "exec" => "scripts/extract-ikconfig",
	    "test" => "scripts/extract-ikconfig",
	},
	{
	    "file" => "vmlinux",
	    "exec" => "scripts/extract-ikconfig",
	    "test" => "scripts/extract-ikconfig",
	},
	{
	    "file" => "/lib/modules/$uname/kernel/kernel/configs.ko",
	    "exec" => "scripts/extract-ikconfig",
	    "test" => "scripts/extract-ikconfig",
	},
	{
	    "file" => "kernel/configs.ko",
	    "exec" => "scripts/extract-ikconfig",
	    "test" => "scripts/extract-ikconfig",
	},
	{
	    "file" => "kernel/configs.o",
	    "exec" => "scripts/extract-ikconfig",
	    "test" => "scripts/extract-ikconfig",
	},
);

sub read_config {
    foreach my $conf (@searchconfigs) {
	my $file = $conf->{"file"};

	next if ( ! -f "$file");

	if (defined($conf->{"test"})) {
	    `$conf->{"test"} $conf->{"file"} 2>/dev/null`;
	    next if ($?);
	}

	my $exec = $conf->{"exec"};

	print STDERR "using config: '$file'\n";

	open(my $infile, '-|', "$exec $file") || die "Failed to run $exec $file";
	my @x = <$infile>;
	close $infile;
	return @x;
    }
    die "No config file found";
}

my @config_file = read_config;

# Parse options
my $localmodconfig = 0;
my $localyesconfig = 0;

GetOptions("localmodconfig" => \$localmodconfig,
	   "localyesconfig" => \$localyesconfig);

# Get the build source and top level Kconfig file (passed in)
my $ksource = ($ARGV[0] ? $ARGV[0] : '.');
my $kconfig = $ARGV[1];
my $lsmod_file = $ENV{'LSMOD'};

my @makefiles = `find $ksource -name Makefile -or -name Kbuild 2>/dev/null`;
chomp @makefiles;

my %depends;
my %selects;
my %prompts;
my %objects;
my $var;
my $iflevel = 0;
my @ifdeps;

# prevent recursion
my %read_kconfigs;

sub read_kconfig {
    my ($kconfig) = @_;

    my $state = "NONE";
    my $config;

    my $cont = 0;
    my $line;

    my $source = "$ksource/$kconfig";
    my $last_source = "";

    # Check for any environment variables used
    while ($source =~ /\$(\w+)/ && $last_source ne $source) {
	my $env = $1;
	$last_source = $source;
	$source =~ s/\$$env/$ENV{$env}/;
    }

    open(my $kinfile, '<', $source) || die "Can't open $kconfig";
    while (<$kinfile>) {
	chomp;

	# Make sure that lines ending with \ continue
	if ($cont) {
	    $_ = $line . " " . $_;
	}

	if (s/\\$//) {
	    $cont = 1;
	    $line = $_;
	    next;
	}

	$cont = 0;

	# collect any Kconfig sources
	if (/^source\s*"(.*)"/) {
	    my $kconfig = $1;
	    # prevent reading twice.
	    if (!defined($read_kconfigs{$kconfig})) {
		$read_kconfigs{$kconfig} = 1;
		read_kconfig($kconfig);
	    }
	    next;
	}

	# configs found
	if (/^\s*(menu)?config\s+(\S+)\s*$/) {
	    $state = "NEW";
	    $config = $2;

	    # Add depends for 'if' nesting
	    for (my $i = 0; $i < $iflevel; $i++) {
		if ($i) {
		    $depends{$config} .= " " . $ifdeps[$i];
		} else {
		    $depends{$config} = $ifdeps[$i];
		}
		$state = "DEP";
	    }

	# collect the depends for the config
	} elsif ($state eq "NEW" && /^\s*depends\s+on\s+(.*)$/) {
	    $state = "DEP";
	    $depends{$config} = $1;
	} elsif ($state eq "DEP" && /^\s*depends\s+on\s+(.*)$/) {
	    $depends{$config} .= " " . $1;
	} elsif ($state eq "DEP" && /^\s*def(_(bool|tristate)|ault)\s+(\S.*)$/) {
	    my $dep = $3;
	    if ($dep !~ /^\s*(y|m|n)\s*$/) {
		$dep =~ s/.*\sif\s+//;
		$depends{$config} .= " " . $dep;
		dprint "Added default depends $dep to $config\n";
	    }

	# Get the configs that select this config
	} elsif ($state ne "NONE" && /^\s*select\s+(\S+)/) {
	    my $conf = $1;
	    if (defined($selects{$conf})) {
		$selects{$conf} .= " " . $config;
	    } else {
		$selects{$conf} = $config;
	    }

	# configs without prompts must be selected
	} elsif ($state ne "NONE" && /^\s*tristate\s\S/) {
	    # note if the config has a prompt
	    $prompts{$config} = 1;

	# Check for if statements
	} elsif (/^if\s+(.*\S)\s*$/) {
	    my $deps = $1;
	    # remove beginning and ending non text
	    $deps =~ s/^[^a-zA-Z0-9_]*//;
	    $deps =~ s/[^a-zA-Z0-9_]*$//;

	    my @deps = split /[^a-zA-Z0-9_]+/, $deps;

	    $ifdeps[$iflevel++] = join ':', @deps;

	} elsif (/^endif/) {

	    $iflevel-- if ($iflevel);

	# stop on "help"
	} elsif (/^\s*help\s*$/) {
	    $state = "NONE";
	}
    }
    close($kinfile);
}

if ($kconfig) {
    read_kconfig($kconfig);
}

# Makefiles can use variables to define their dependencies
sub convert_vars {
    my ($line, %vars) = @_;

    my $process = "";

    while ($line =~ s/^(.*?)(\$\((.*?)\))//) {
	my $start = $1;
	my $variable = $2;
	my $var = $3;

	if (defined($vars{$var})) {
	    $process .= $start . $vars{$var};
	} else {
	    $process .= $start . $variable;
	}
    }

    $process .= $line;

    return $process;
}

# Read all Makefiles to map the configs to the objects
foreach my $makefile (@makefiles) {

    my $line = "";
    my %make_vars;

    open(my $infile, '<', $makefile) || die "Can't open $makefile";
    while (<$infile>) {
	# if this line ends with a backslash, continue
	chomp;
	if (/^(.*)\\$/) {
	    $line .= $1;
	    next;
	}

	$line .= $_;
	$_ = $line;
	$line = "";

	my $objs;

	# Convert variables in a line (could define configs)
	$_ = convert_vars($_, %make_vars);

	# collect objects after obj-$(CONFIG_FOO_BAR)
	if (/obj-\$\((CONFIG_[^\)]*)\)\s*[+:]?=\s*(.*)/) {
	    $var = $1;
	    $objs = $2;

	# check if variables are set
	} elsif (/^\s*(\S+)\s*[:]?=\s*(.*\S)/) {
	    $make_vars{$1} = $2;
	}
	if (defined($objs)) {
	    foreach my $obj (split /\s+/,$objs) {
		$obj =~ s/-/_/g;
		if ($obj =~ /(.*)\.o$/) {
		    # Objects may be enabled by more than one config.
		    # Store configs in an array.
		    my @arr;

		    if (defined($objects{$1})) {
			@arr = @{$objects{$1}};
		    }

		    $arr[$#arr+1] = $var;

		    # The objects have a hash mapping to a reference
		    # of an array of configs.
		    $objects{$1} = \@arr;
		}
	    }
	}
    }
    close($infile);
}

my %modules;
my $linfile;

if (defined($lsmod_file)) {
    if ( ! -f $lsmod_file) {
	if ( -f $ENV{'objtree'}."/".$lsmod_file) {
	    $lsmod_file = $ENV{'objtree'}."/".$lsmod_file;
	} else {
		die "$lsmod_file not found";
	}
    }

    my $otype = ( -x $lsmod_file) ? '-|' : '<';
    open($linfile, $otype, $lsmod_file);

} else {

    # see what modules are loaded on this system
    my $lsmod;

    foreach my $dir ( ("/sbin", "/bin", "/usr/sbin", "/usr/bin") ) {
	if ( -x "$dir/lsmod" ) {
	    $lsmod = "$dir/lsmod";
	    last;
	}
}
    if (!defined($lsmod)) {
	# try just the path
	$lsmod = "lsmod";
    }

    open($linfile, '-|', $lsmod) || die "Can not call lsmod with $lsmod";
}

while (<$linfile>) {
	next if (/^Module/);  # Skip the first line.
	if (/^(\S+)/) {
		$modules{$1} = 1;
	}
}
close ($linfile);

# add to the configs hash all configs that are needed to enable
# a loaded module. This is a direct obj-${CONFIG_FOO} += bar.o
# where we know we need bar.o so we add FOO to the list.
my %configs;
foreach my $module (keys(%modules)) {
    if (defined($objects{$module})) {
	my @arr = @{$objects{$module}};
	foreach my $conf (@arr) {
	    $configs{$conf} = $module;
	    dprint "$conf added by direct ($module)\n";
	    if ($debugprint) {
		my $c=$conf;
		$c =~ s/^CONFIG_//;
		if (defined($depends{$c})) {
		    dprint " deps = $depends{$c}\n";
		} else {
		    dprint " no deps\n";
		}
	    }
	}
    } else {
	# Most likely, someone has a custom (binary?) module loaded.
	print STDERR "$module config not found!!\n";
    }
}

# Read the current config, and see what is enabled. We want to
# ignore configs that we would not enable anyway.

my %orig_configs;
my $valid = "A-Za-z_0-9";

foreach my $line (@config_file) {
    $_ = $line;

    if (/(CONFIG_[$valid]*)=(m|y)/) {
	$orig_configs{$1} = $2;
    }
}

my $repeat = 1;

my $depconfig;

#
# Note, we do not care about operands (like: &&, ||, !) we want to add any
# config that is in the depend list of another config. This script does
# not enable configs that are not already enabled. If we come across a
# config A that depends on !B, we can still add B to the list of depends
# to keep on. If A was on in the original config, B would not have been
# and B would not be turned on by this script.
#
sub parse_config_depends
{
    my ($p) = @_;

    while ($p =~ /[$valid]/) {

	if ($p =~ /^[^$valid]*([$valid]+)/) {
	    my $conf = "CONFIG_" . $1;

	    $p =~ s/^[^$valid]*[$valid]+//;

	    # We only need to process if the depend config is a module
	    if (!defined($orig_configs{$conf}) || !$orig_configs{conf} eq "m") {
		next;
	    }

	    if (!defined($configs{$conf})) {
		# We must make sure that this config has its
		# dependencies met.
		$repeat = 1; # do again
		dprint "$conf selected by depend $depconfig\n";
		$configs{$conf} = 1;
	    }
	} else {
	    die "this should never happen";
	}
    }
}

# Select is treated a bit differently than depends. We call this
# when a config has no prompt and requires another config to be
# selected. We use to just select all configs that selected this
# config, but found that that can balloon into enabling hundreds
# of configs that we do not care about.
#
# The idea is we look at all the configs that select it. If one
# is already in our list of configs to enable, then there's nothing
# else to do. If there isn't, we pick the first config that was
# enabled in the orignal config and use that.
sub parse_config_selects
{
    my ($config, $p) = @_;

    my $next_config;

    while ($p =~ /[$valid]/) {

	if ($p =~ /^[^$valid]*([$valid]+)/) {
	    my $conf = "CONFIG_" . $1;

	    $p =~ s/^[^$valid]*[$valid]+//;

	    # Make sure that this config exists in the current .config file
	    if (!defined($orig_configs{$conf})) {
		dprint "$conf not set for $config select\n";
		next;
	    }

	    # Check if something other than a module selects this config
	    if (defined($orig_configs{$conf}) && $orig_configs{$conf} ne "m") {
		dprint "$conf (non module) selects config, we are good\n";
		# we are good with this
		return;
	    }
	    if (defined($configs{$conf})) {
		dprint "$conf selects $config so we are good\n";
		# A set config selects this config, we are good
		return;
	    }
	    # Set this config to be selected
	    if (!defined($next_config)) {
		$next_config = $conf;
	    }
	} else {
	    die "this should never happen";
	}
    }

    # If no possible config selected this, then something happened.
    if (!defined($next_config)) {
	print STDERR "WARNING: $config is required, but nothing in the\n";
	print STDERR "  current config selects it.\n";
	return;
    }

    # If we are here, then we found no config that is set and
    # selects this config. Repeat.
    $repeat = 1;
    # Make this config need to be selected
    $configs{$next_config} = 1;
    dprint "$next_config selected by select $config\n";
}

my %process_selects;

# loop through all configs, select their dependencies.
sub loop_depend {
    $repeat = 1;

    while ($repeat) {
	$repeat = 0;

      forloop:
	foreach my $config (keys %configs) {

	    # If this config is not a module, we do not need to process it
	    if (defined($orig_configs{$config}) && $orig_configs{$config} ne "m") {
		next forloop;
	    }

	    $config =~ s/^CONFIG_//;
	    $depconfig = $config;

	    if (defined($depends{$config})) {
		# This config has dependencies. Make sure they are also included
		parse_config_depends $depends{$config};
	    }

	    # If the config has no prompt, then we need to check if a config
	    # that is enabled selected it. Or if we need to enable one.
	    if (!defined($prompts{$config}) && defined($selects{$config})) {
		$process_selects{$config} = 1;
	    }
	}
    }
}

sub loop_select {

    foreach my $config (keys %process_selects) {
	$config =~ s/^CONFIG_//;

	dprint "Process select $config\n";

	# config has no prompt and must be selected.
	parse_config_selects $config, $selects{$config};
    }
}

while ($repeat) {
    # Get the first set of configs and their dependencies.
    loop_depend;

    $repeat = 0;

    # Now we need to see if we have to check selects;
    loop_select;
}

my %setconfigs;

# Finally, read the .config file and turn off any module enabled that
# we could not find a reason to keep enabled.
foreach my $line (@config_file) {
    $_ = $line;

    if (/CONFIG_IKCONFIG/) {
	if (/# CONFIG_IKCONFIG is not set/) {
	    # enable IKCONFIG at least as a module
	    print "CONFIG_IKCONFIG=m\n";
	    # don't ask about PROC
	    print "# CONFIG_IKCONFIG_PROC is not set\n";
	} else {
	    print;
	}
	next;
    }

    if (/^(CONFIG.*)=(m|y)/) {
	if (defined($configs{$1})) {
	    if ($localyesconfig) {
	        $setconfigs{$1} = 'y';
		print "$1=y\n";
		next;
	    } else {
	        $setconfigs{$1} = $2;
	    }
	} elsif ($2 eq "m") {
	    print "# $1 is not set\n";
	    next;
	}
    }
    print;
}

# Integrity check, make sure all modules that we want enabled do
# indeed have their configs set.
loop:
foreach my $module (keys(%modules)) {
    if (defined($objects{$module})) {
	my @arr = @{$objects{$module}};
	foreach my $conf (@arr) {
	    if (defined($setconfigs{$conf})) {
		next loop;
	    }
	}
	print STDERR "module $module did not have configs";
	foreach my $conf (@arr) {
	    print STDERR " " , $conf;
	}
	print STDERR "\n";
    }
}
OpenPOWER on IntegriCloud