*
* Usage: nm -n vmlinux | scripts/kallsyms [--all-symbols] > symbols.S
*
- * ChangeLog:
- *
- * (25/Aug/2004) Paulo Marques <pmarques@grupopie.com>
- * Changed the compression method from stem compression to "table lookup"
- * compression
- *
* 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
*
*/
-#define _GNU_SOURCE
-
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
-#define KSYM_NAME_LEN 127
-
+#define KSYM_NAME_LEN 128
struct sym_entry {
unsigned long long addr;
unsigned int len;
+ unsigned int start_pos;
unsigned char *sym;
};
-
static struct sym_entry *table;
static unsigned int table_size, table_cnt;
-static unsigned long long _text, _stext, _etext, _sinittext, _einittext, _sextratext, _eextratext;
+static unsigned long long _text, _stext, _etext, _sinittext, _einittext;
static int all_symbols = 0;
static char symbol_prefix_char = '\0';
_sinittext = s->addr;
else if (strcmp(sym, "_einittext") == 0)
_einittext = s->addr;
- else if (strcmp(sym, "_sextratext") == 0)
- _sextratext = s->addr;
- else if (strcmp(sym, "_eextratext") == 0)
- _eextratext = s->addr;
else if (toupper(stype) == 'A')
{
/* Keep these useful absolute symbols */
/* 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 */
* and inittext sections are discarded */
if (!all_symbols) {
if ((s->addr < _stext || s->addr > _etext)
- && (s->addr < _sinittext || s->addr > _einittext)
- && (s->addr < _sextratext || s->addr > _eextratext))
+ && (s->addr < _sinittext || s->addr > _einittext))
return 0;
/* Corner case. Discard any symbols with the same value as
- * _etext _einittext or _eextratext; 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.
+ * _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 == _etext && strcmp((char*)s->sym + offset, "_etext")) ||
- (s->addr == _einittext && strcmp((char*)s->sym + offset, "_einittext")) ||
- (s->addr == _eextratext && strcmp((char*)s->sym + offset, "_eextratext")))
+ if ((s->addr == _etext &&
+ strcmp((char *)s->sym + offset, "_etext")) ||
+ (s->addr == _einittext &&
+ strcmp((char *)s->sym + offset, "_einittext")))
return 0;
}
exit (1);
}
}
- if (read_symbol(in, &table[table_cnt]) == 0)
+ if (read_symbol(in, &table[table_cnt]) == 0) {
+ table[table_cnt].start_pos = table_cnt;
table_cnt++;
+ }
}
}
unsigned int i, k, off;
unsigned int best_idx[256];
unsigned int *markers;
- char buf[KSYM_NAME_LEN+1];
+ char buf[KSYM_NAME_LEN];
printf("#include <asm/types.h>\n");
printf("#if BITS_PER_LONG == 64\n");
printf("#define ALGN .align 4\n");
printf("#endif\n");
- printf(".data\n");
+ printf("\t.section .rodata, \"a\"\n");
/* Provide proper symbols relocatability by their '_text'
* relativeness. The symbol names cannot be used to construct
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)
p1 = table[i].sym;
/* find the token on the symbol */
- p2 = memmem(p1, len, str, 2);
+ p2 = find_token(p1, len, str);
if (!p2) continue;
/* decrease the counts for this symbol's tokens */
if (size < 2) break;
/* find the token on the symbol */
- p2 = memmem(p1, size, str, 2);
+ p2 = find_token(p1, size, str);
} while (p2);
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);
+}
int main(int argc, char **argv)
{
usage();
read_map(stdin);
+ sort_symbols();
optimize_token_table();
write_src();
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff