aboutsummaryrefslogtreecommitdiffstats
path: root/scripts/kconfig/streamline_config.pl
blob: 0d800820c3cd72d6408079b6dbdec96eac954515 (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
#!/usr/bin/perl -w
#
# Copywrite 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
#
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 find_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(CIN, "$exec $file |") || die "Failed to run $exec $file";
	return;
    }
    die "No config file found";
}

find_config;

# Get the build source and top level Kconfig file (passed in)
my $ksource = $ARGV[0];
my $kconfig = $ARGV[1];

my @makefiles = `find $ksource -name Makefile`;
my %depends;
my %selects;
my %prompts;
my %objects;
my $var;
my $cont = 0;

# prevent recursion
my %read_kconfigs;

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

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

    open(KIN, "$ksource/$kconfig") || die "Can't open $kconfig";
    while (<KIN>) {
	chomp;

	# collect any Kconfig sources
	if (/^source\s*"(.*)"/) {
	    $kconfigs[$#kconfigs+1] = $1;
	}

	# configs found
	if (/^\s*config\s+(\S+)\s*$/) {
	    $state = "NEW";
	    $config = $1;

	# 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;

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

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

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

    # read in any configs that were found.
    foreach $kconfig (@kconfigs) {
	if (!defined($read_kconfigs{$kconfig})) {
	    $read_kconfigs{$kconfig} = 1;
	    read_kconfig($kconfig);
	}
    }
}

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

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

    open(MIN,$makefile) || die "Can't open $makefile";
    while (<MIN>) {
	my $objs;

	# is this a line after a line with a backslash?
	if ($cont && /(\S.*)$/) {
	    $objs = $1;
	}
	$cont = 0;

	# collect objects after obj-$(CONFIG_FOO_BAR)
	if (/obj-\$\((CONFIG_[^\)]*)\)\s*[+:]?=\s*(.*)/) {
	    $var = $1;
	    $objs = $2;
	}
	if (defined($objs)) {
	    # test if the line ends with a backslash
	    if ($objs =~ m,(.*)\\$,) {
		$objs = $1;
		$cont = 1;
	    }

	    foreach my $obj (split /\s+/,$objs) {
		$obj =~ s/-/_/g;
		if ($obj =~ /(.*)\.o$/) {
		    # Objects may bes 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(MIN);
}

my %modules;

# see what modules are loaded on this system
open(LIN,"/sbin/lsmod|") || die "Cant lsmod";
while (<LIN>) {
	next if (/^Module/);  # Skip the first line.
	if (/^(\S+)/) {
		$modules{$1} = 1;
	}
}
close (LIN);

# add to the configs hash all configs that are needed to enable
# a loaded module.
my %configs;
foreach my $module (keys(%modules)) {
    if (defined($objects{$module})) {
	@arr = @{$objects{$module}};
	foreach my $conf (@arr) {
	    $configs{$conf} = $module;
	}
    } else {
	# Most likely, someone has a custom (binary?) module loaded.
	print STDERR "$module config not found!!\n";
    }
}

my $valid = "A-Za-z_0-9";
my $repeat = 1;

#
# 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_dep_select
{
    my ($p) = @_;

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

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

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

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

while ($repeat) {
    $repeat = 0;

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

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

	if (defined($prompt{$config}) || !defined($selects{$config})) {
	    next;
	}

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

my %setconfigs;

# Finally, read the .config file and turn off any module enabled that
# we could not find a reason to keep enabled.
while(<CIN>) {

    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})) {
	    $setconfigs{$1} = $2;
	} elsif ($2 eq "m") {
	    print "# $1 is not set\n";
	    next;
	}
    }
    print;
}
close(CIN);

# 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";
    }
}

Privacy Policy