Free Electrons

Embedded Linux Experts

  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
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
/* Generate assembler source containing symbol information
 *
 * Copyright 2002       by Kai Germaschewski
 *
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 *
 * Usage: nm -n vmlinux | scripts/kallsyms [--all-symbols] > symbols.S
 *
 *      Table compression uses all the unused char codes on the symbols and
 *  maps these to the most used substrings (tokens). For instance, it might
 *  map char code 0xF7 to represent "write_" and then in every symbol where
 *  "write_" appears it can be replaced by 0xF7, saving 5 bytes.
 *      The used codes themselves are also placed in the table so that the
 *  decompresion can work without "special cases".
 *      Applied to kernel symbols, this usually produces a compression ratio
 *  of about 50%.
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <limits.h>

#ifndef ARRAY_SIZE
#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
#endif

#define KSYM_NAME_LEN		128

struct sym_entry {
	unsigned long long addr;
	unsigned int len;
	unsigned int start_pos;
	unsigned char *sym;
	unsigned int percpu_absolute;
};

struct addr_range {
	const char *start_sym, *end_sym;
	unsigned long long start, end;
};

static unsigned long long _text;
static unsigned long long relative_base;
static struct addr_range text_ranges[] = {
	{ "_stext",     "_etext"     },
	{ "_sinittext", "_einittext" },
	{ "_stext_l1",  "_etext_l1"  },	/* Blackfin on-chip L1 inst SRAM */
	{ "_stext_l2",  "_etext_l2"  },	/* Blackfin on-chip L2 SRAM */
};
#define text_range_text     (&text_ranges[0])
#define text_range_inittext (&text_ranges[1])

static struct addr_range percpu_range = {
	"__per_cpu_start", "__per_cpu_end", -1ULL, 0
};

static struct sym_entry *table;
static unsigned int table_size, table_cnt;
static int all_symbols = 0;
static int absolute_percpu = 0;
static char symbol_prefix_char = '\0';
static int base_relative = 0;

int token_profit[0x10000];

/* the table that holds the result of the compression */
unsigned char best_table[256][2];
unsigned char best_table_len[256];


static void usage(void)
{
	fprintf(stderr, "Usage: kallsyms [--all-symbols] "
			"[--symbol-prefix=<prefix char>] "
			"[--base-relative] < in.map > out.S\n");
	exit(1);
}

/*
 * This ignores the intensely annoying "mapping symbols" found
 * in ARM ELF files: $a, $t and $d.
 */
static inline int is_arm_mapping_symbol(const char *str)
{
	return str[0] == '$' && strchr("axtd", str[1])
	       && (str[2] == '\0' || str[2] == '.');
}

static int check_symbol_range(const char *sym, unsigned long long addr,
			      struct addr_range *ranges, int entries)
{
	size_t i;
	struct addr_range *ar;

	for (i = 0; i < entries; ++i) {
		ar = &ranges[i];

		if (strcmp(sym, ar->start_sym) == 0) {
			ar->start = addr;
			return 0;
		} else if (strcmp(sym, ar->end_sym) == 0) {
			ar->end = addr;
			return 0;
		}
	}

	return 1;
}

static int read_symbol(FILE *in, struct sym_entry *s)
{
	char str[500];
	char *sym, stype;
	int rc;

	rc = fscanf(in, "%llx %c %499s\n", &s->addr, &stype, str);
	if (rc != 3) {
		if (rc != EOF && fgets(str, 500, in) == NULL)
			fprintf(stderr, "Read error or end of file.\n");
		return -1;
	}
	if (strlen(str) > KSYM_NAME_LEN) {
		fprintf(stderr, "Symbol %s too long for kallsyms (%zu vs %d).\n"
				"Please increase KSYM_NAME_LEN both in kernel and kallsyms.c\n",
			str, strlen(str), KSYM_NAME_LEN);
		return -1;
	}

	sym = str;
	/* skip prefix char */
	if (symbol_prefix_char && str[0] == symbol_prefix_char)
		sym++;

	/* Ignore most absolute/undefined (?) symbols. */
	if (strcmp(sym, "_text") == 0)
		_text = s->addr;
	else if (check_symbol_range(sym, s->addr, text_ranges,
				    ARRAY_SIZE(text_ranges)) == 0)
		/* nothing to do */;
	else if (toupper(stype) == 'A')
	{
		/* Keep these useful absolute symbols */
		if (strcmp(sym, "__kernel_syscall_via_break") &&
		    strcmp(sym, "__kernel_syscall_via_epc") &&
		    strcmp(sym, "__kernel_sigtramp") &&
		    strcmp(sym, "__gp"))
			return -1;

	}
	else if (toupper(stype) == 'U' ||
		 is_arm_mapping_symbol(sym))
		return -1;
	/* exclude also MIPS ELF local symbols ($L123 instead of .L123) */
	else if (str[0] == '$')
		return -1;
	/* exclude debugging symbols */
	else if (stype == 'N')
		return -1;

	/* include the type field in the symbol name, so that it gets
	 * compressed together */
	s->len = strlen(str) + 1;
	s->sym = malloc(s->len + 1);
	if (!s->sym) {
		fprintf(stderr, "kallsyms failure: "
			"unable to allocate required amount of memory\n");
		exit(EXIT_FAILURE);
	}
	strcpy((char *)s->sym + 1, str);
	s->sym[0] = stype;

	s->percpu_absolute = 0;

	/* Record if we've found __per_cpu_start/end. */
	check_symbol_range(sym, s->addr, &percpu_range, 1);

	return 0;
}

static int symbol_in_range(struct sym_entry *s, struct addr_range *ranges,
			   int entries)
{
	size_t i;
	struct addr_range *ar;

	for (i = 0; i < entries; ++i) {
		ar = &ranges[i];

		if (s->addr >= ar->start && s->addr <= ar->end)
			return 1;
	}

	return 0;
}

static int symbol_valid(struct sym_entry *s)
{
	/* Symbols which vary between passes.  Passes 1 and 2 must have
	 * identical symbol lists.  The kallsyms_* symbols below are only added
	 * after pass 1, they would be included in pass 2 when --all-symbols is
	 * specified so exclude them to get a stable symbol list.
	 */
	static char *special_symbols[] = {
		"kallsyms_addresses",
		"kallsyms_offsets",
		"kallsyms_relative_base",
		"kallsyms_num_syms",
		"kallsyms_names",
		"kallsyms_markers",
		"kallsyms_token_table",
		"kallsyms_token_index",

	/* Exclude linker generated symbols which vary between passes */
		"_SDA_BASE_",		/* ppc */
		"_SDA2_BASE_",		/* ppc */
		NULL };

	static char *special_prefixes[] = {
		"__crc_",		/* modversions */
		NULL };

	static char *special_suffixes[] = {
		"_veneer",		/* arm */
		"_from_arm",		/* arm */
		"_from_thumb",		/* arm */
		NULL };

	int i;
	char *sym_name = (char *)s->sym + 1;

	/* skip prefix char */
	if (symbol_prefix_char && *sym_name == symbol_prefix_char)
		sym_name++;


	/* if --all-symbols is not specified, then symbols outside the text
	 * and inittext sections are discarded */
	if (!all_symbols) {
		if (symbol_in_range(s, text_ranges,
				    ARRAY_SIZE(text_ranges)) == 0)
			return 0;
		/* Corner case.  Discard any symbols with the same value as
		 * _etext _einittext; they can move between pass 1 and 2 when
		 * the kallsyms data are added.  If these symbols move then
		 * they may get dropped in pass 2, which breaks the kallsyms
		 * rules.
		 */
		if ((s->addr == text_range_text->end &&
				strcmp(sym_name,
				       text_range_text->end_sym)) ||
		    (s->addr == text_range_inittext->end &&
				strcmp(sym_name,
				       text_range_inittext->end_sym)))
			return 0;
	}

	/* Exclude symbols which vary between passes. */
	for (i = 0; special_symbols[i]; i++)
		if (strcmp(sym_name, special_symbols[i]) == 0)
			return 0;

	for (i = 0; special_prefixes[i]; i++) {
		int l = strlen(special_prefixes[i]);

		if (l <= strlen(sym_name) &&
		    strncmp(sym_name, special_prefixes[i], l) == 0)
			return 0;
	}

	for (i = 0; special_suffixes[i]; i++) {
		int l = strlen(sym_name) - strlen(special_suffixes[i]);

		if (l >= 0 && strcmp(sym_name + l, special_suffixes[i]) == 0)
			return 0;
	}

	return 1;
}

static void read_map(FILE *in)
{
	while (!feof(in)) {
		if (table_cnt >= table_size) {
			table_size += 10000;
			table = realloc(table, sizeof(*table) * table_size);
			if (!table) {
				fprintf(stderr, "out of memory\n");
				exit (1);
			}
		}
		if (read_symbol(in, &table[table_cnt]) == 0) {
			table[table_cnt].start_pos = table_cnt;
			table_cnt++;
		}
	}
}

static void output_label(char *label)
{
	if (symbol_prefix_char)
		printf(".globl %c%s\n", symbol_prefix_char, label);
	else
		printf(".globl %s\n", label);
	printf("\tALGN\n");
	if (symbol_prefix_char)
		printf("%c%s:\n", symbol_prefix_char, label);
	else
		printf("%s:\n", label);
}

/* uncompress a compressed symbol. When this function is called, the best table
 * might still be compressed itself, so the function needs to be recursive */
static int expand_symbol(unsigned char *data, int len, char *result)
{
	int c, rlen, total=0;

	while (len) {
		c = *data;
		/* if the table holds a single char that is the same as the one
		 * we are looking for, then end the search */
		if (best_table[c][0]==c && best_table_len[c]==1) {
			*result++ = c;
			total++;
		} else {
			/* if not, recurse and expand */
			rlen = expand_symbol(best_table[c], best_table_len[c], result);
			total += rlen;
			result += rlen;
		}
		data++;
		len--;
	}
	*result=0;

	return total;
}

static int symbol_absolute(struct sym_entry *s)
{
	return s->percpu_absolute;
}

static void write_src(void)
{
	unsigned int i, k, off;
	unsigned int best_idx[256];
	unsigned int *markers;
	char buf[KSYM_NAME_LEN];

	printf("#include <asm/types.h>\n");
	printf("#if BITS_PER_LONG == 64\n");
	printf("#define PTR .quad\n");
	printf("#define ALGN .align 8\n");
	printf("#else\n");
	printf("#define PTR .long\n");
	printf("#define ALGN .align 4\n");
	printf("#endif\n");

	printf("\t.section .rodata, \"a\"\n");

	/* Provide proper symbols relocatability by their relativeness
	 * to a fixed anchor point in the runtime image, either '_text'
	 * for absolute address tables, in which case the linker will
	 * emit the final addresses at build time. Otherwise, use the
	 * offset relative to the lowest value encountered of all relative
	 * symbols, and emit non-relocatable fixed offsets that will be fixed
	 * up at runtime.
	 *
	 * The symbol names cannot be used to construct normal symbol
	 * references as the list of symbols contains symbols that are
	 * declared static and are private to their .o files.  This prevents
	 * .tmp_kallsyms.o or any other object from referencing them.
	 */
	if (!base_relative)
		output_label("kallsyms_addresses");
	else
		output_label("kallsyms_offsets");

	for (i = 0; i < table_cnt; i++) {
		if (base_relative) {
			long long offset;
			int overflow;

			if (!absolute_percpu) {
				offset = table[i].addr - relative_base;
				overflow = (offset < 0 || offset > UINT_MAX);
			} else if (symbol_absolute(&table[i])) {
				offset = table[i].addr;
				overflow = (offset < 0 || offset > INT_MAX);
			} else {
				offset = relative_base - table[i].addr - 1;
				overflow = (offset < INT_MIN || offset >= 0);
			}
			if (overflow) {
				fprintf(stderr, "kallsyms failure: "
					"%s symbol value %#llx out of range in relative mode\n",
					symbol_absolute(&table[i]) ? "absolute" : "relative",
					table[i].addr);
				exit(EXIT_FAILURE);
			}
			printf("\t.long\t%#x\n", (int)offset);
		} else if (!symbol_absolute(&table[i])) {
			if (_text <= table[i].addr)
				printf("\tPTR\t_text + %#llx\n",
					table[i].addr - _text);
			else
				printf("\tPTR\t_text - %#llx\n",
					_text - table[i].addr);
		} else {
			printf("\tPTR\t%#llx\n", table[i].addr);
		}
	}
	printf("\n");

	if (base_relative) {
		output_label("kallsyms_relative_base");
		printf("\tPTR\t_text - %#llx\n", _text - relative_base);
		printf("\n");
	}

	output_label("kallsyms_num_syms");
	printf("\tPTR\t%d\n", table_cnt);
	printf("\n");

	/* table of offset markers, that give the offset in the compressed stream
	 * every 256 symbols */
	markers = malloc(sizeof(unsigned int) * ((table_cnt + 255) / 256));
	if (!markers) {
		fprintf(stderr, "kallsyms failure: "
			"unable to allocate required memory\n");
		exit(EXIT_FAILURE);
	}

	output_label("kallsyms_names");
	off = 0;
	for (i = 0; i < table_cnt; i++) {
		if ((i & 0xFF) == 0)
			markers[i >> 8] = off;

		printf("\t.byte 0x%02x", table[i].len);
		for (k = 0; k < table[i].len; k++)
			printf(", 0x%02x", table[i].sym[k]);
		printf("\n");

		off += table[i].len + 1;
	}
	printf("\n");

	output_label("kallsyms_markers");
	for (i = 0; i < ((table_cnt + 255) >> 8); i++)
		printf("\tPTR\t%d\n", markers[i]);
	printf("\n");

	free(markers);

	output_label("kallsyms_token_table");
	off = 0;
	for (i = 0; i < 256; i++) {
		best_idx[i] = off;
		expand_symbol(best_table[i], best_table_len[i], buf);
		printf("\t.asciz\t\"%s\"\n", buf);
		off += strlen(buf) + 1;
	}
	printf("\n");

	output_label("kallsyms_token_index");
	for (i = 0; i < 256; i++)
		printf("\t.short\t%d\n", best_idx[i]);
	printf("\n");
}


/* table lookup compression functions */

/* count all the possible tokens in a symbol */
static void learn_symbol(unsigned char *symbol, int len)
{
	int i;

	for (i = 0; i < len - 1; i++)
		token_profit[ symbol[i] + (symbol[i + 1] << 8) ]++;
}

/* decrease the count for all the possible tokens in a symbol */
static void forget_symbol(unsigned char *symbol, int len)
{
	int i;

	for (i = 0; i < len - 1; i++)
		token_profit[ symbol[i] + (symbol[i + 1] << 8) ]--;
}

/* remove all the invalid symbols from the table and do the initial token count */
static void build_initial_tok_table(void)
{
	unsigned int i, pos;

	pos = 0;
	for (i = 0; i < table_cnt; i++) {
		if ( symbol_valid(&table[i]) ) {
			if (pos != i)
				table[pos] = table[i];
			learn_symbol(table[pos].sym, table[pos].len);
			pos++;
		}
	}
	table_cnt = pos;
}

static void *find_token(unsigned char *str, int len, unsigned char *token)
{
	int i;

	for (i = 0; i < len - 1; i++) {
		if (str[i] == token[0] && str[i+1] == token[1])
			return &str[i];
	}
	return NULL;
}

/* replace a given token in all the valid symbols. Use the sampled symbols
 * to update the counts */
static void compress_symbols(unsigned char *str, int idx)
{
	unsigned int i, len, size;
	unsigned char *p1, *p2;

	for (i = 0; i < table_cnt; i++) {

		len = table[i].len;
		p1 = table[i].sym;

		/* find the token on the symbol */
		p2 = find_token(p1, len, str);
		if (!p2) continue;

		/* decrease the counts for this symbol's tokens */
		forget_symbol(table[i].sym, len);

		size = len;

		do {
			*p2 = idx;
			p2++;
			size -= (p2 - p1);
			memmove(p2, p2 + 1, size);
			p1 = p2;
			len--;

			if (size < 2) break;

			/* find the token on the symbol */
			p2 = find_token(p1, size, str);

		} while (p2);

		table[i].len = len;

		/* increase the counts for this symbol's new tokens */
		learn_symbol(table[i].sym, len);
	}
}

/* search the token with the maximum profit */
static int find_best_token(void)
{
	int i, best, bestprofit;

	bestprofit=-10000;
	best = 0;

	for (i = 0; i < 0x10000; i++) {
		if (token_profit[i] > bestprofit) {
			best = i;
			bestprofit = token_profit[i];
		}
	}
	return best;
}

/* this is the core of the algorithm: calculate the "best" table */
static void optimize_result(void)
{
	int i, best;

	/* using the '\0' symbol last allows compress_symbols to use standard
	 * fast string functions */
	for (i = 255; i >= 0; i--) {

		/* if this table slot is empty (it is not used by an actual
		 * original char code */
		if (!best_table_len[i]) {

			/* find the token with the breates profit value */
			best = find_best_token();
			if (token_profit[best] == 0)
				break;

			/* place it in the "best" table */
			best_table_len[i] = 2;
			best_table[i][0] = best & 0xFF;
			best_table[i][1] = (best >> 8) & 0xFF;

			/* replace this token in all the valid symbols */
			compress_symbols(best_table[i], i);
		}
	}
}

/* start by placing the symbols that are actually used on the table */
static void insert_real_symbols_in_table(void)
{
	unsigned int i, j, c;

	memset(best_table, 0, sizeof(best_table));
	memset(best_table_len, 0, sizeof(best_table_len));

	for (i = 0; i < table_cnt; i++) {
		for (j = 0; j < table[i].len; j++) {
			c = table[i].sym[j];
			best_table[c][0]=c;
			best_table_len[c]=1;
		}
	}
}

static void optimize_token_table(void)
{
	build_initial_tok_table();

	insert_real_symbols_in_table();

	/* When valid symbol is not registered, exit to error */
	if (!table_cnt) {
		fprintf(stderr, "No valid symbol.\n");
		exit(1);
	}

	optimize_result();
}

/* guess for "linker script provide" symbol */
static int may_be_linker_script_provide_symbol(const struct sym_entry *se)
{
	const char *symbol = (char *)se->sym + 1;
	int len = se->len - 1;

	if (len < 8)
		return 0;

	if (symbol[0] != '_' || symbol[1] != '_')
		return 0;

	/* __start_XXXXX */
	if (!memcmp(symbol + 2, "start_", 6))
		return 1;

	/* __stop_XXXXX */
	if (!memcmp(symbol + 2, "stop_", 5))
		return 1;

	/* __end_XXXXX */
	if (!memcmp(symbol + 2, "end_", 4))
		return 1;

	/* __XXXXX_start */
	if (!memcmp(symbol + len - 6, "_start", 6))
		return 1;

	/* __XXXXX_end */
	if (!memcmp(symbol + len - 4, "_end", 4))
		return 1;

	return 0;
}

static int prefix_underscores_count(const char *str)
{
	const char *tail = str;

	while (*tail == '_')
		tail++;

	return tail - str;
}

static int compare_symbols(const void *a, const void *b)
{
	const struct sym_entry *sa;
	const struct sym_entry *sb;
	int wa, wb;

	sa = a;
	sb = b;

	/* sort by address first */
	if (sa->addr > sb->addr)
		return 1;
	if (sa->addr < sb->addr)
		return -1;

	/* sort by "weakness" type */
	wa = (sa->sym[0] == 'w') || (sa->sym[0] == 'W');
	wb = (sb->sym[0] == 'w') || (sb->sym[0] == 'W');
	if (wa != wb)
		return wa - wb;

	/* sort by "linker script provide" type */
	wa = may_be_linker_script_provide_symbol(sa);
	wb = may_be_linker_script_provide_symbol(sb);
	if (wa != wb)
		return wa - wb;

	/* sort by the number of prefix underscores */
	wa = prefix_underscores_count((const char *)sa->sym + 1);
	wb = prefix_underscores_count((const char *)sb->sym + 1);
	if (wa != wb)
		return wa - wb;

	/* sort by initial order, so that other symbols are left undisturbed */
	return sa->start_pos - sb->start_pos;
}

static void sort_symbols(void)
{
	qsort(table, table_cnt, sizeof(struct sym_entry), compare_symbols);
}

static void make_percpus_absolute(void)
{
	unsigned int i;

	for (i = 0; i < table_cnt; i++)
		if (symbol_in_range(&table[i], &percpu_range, 1)) {
			/*
			 * Keep the 'A' override for percpu symbols to
			 * ensure consistent behavior compared to older
			 * versions of this tool.
			 */
			table[i].sym[0] = 'A';
			table[i].percpu_absolute = 1;
		}
}

/* find the minimum non-absolute symbol address */
static void record_relative_base(void)
{
	unsigned int i;

	relative_base = -1ULL;
	for (i = 0; i < table_cnt; i++)
		if (!symbol_absolute(&table[i]) &&
		    table[i].addr < relative_base)
			relative_base = table[i].addr;
}

int main(int argc, char **argv)
{
	if (argc >= 2) {
		int i;
		for (i = 1; i < argc; i++) {
			if(strcmp(argv[i], "--all-symbols") == 0)
				all_symbols = 1;
			else if (strcmp(argv[i], "--absolute-percpu") == 0)
				absolute_percpu = 1;
			else if (strncmp(argv[i], "--symbol-prefix=", 16) == 0) {
				char *p = &argv[i][16];
				/* skip quote */
				if ((*p == '"' && *(p+2) == '"') || (*p == '\'' && *(p+2) == '\''))
					p++;
				symbol_prefix_char = *p;
			} else if (strcmp(argv[i], "--base-relative") == 0)
				base_relative = 1;
			else
				usage();
		}
	} else if (argc != 1)
		usage();

	read_map(stdin);
	if (absolute_percpu)
		make_percpus_absolute();
	if (base_relative)
		record_relative_base();
	sort_symbols();
	optimize_token_table();
	write_src();

	return 0;
}