symbol.c 39.8 KB
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#include <dirent.h>
#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <fcntl.h>
#include <unistd.h>
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#include <inttypes.h>
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#include "build-id.h"
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#include "util.h"
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#include "debug.h"
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#include "machine.h"
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#include "symbol.h"
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#include "strlist.h"
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#include <elf.h>
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#include <limits.h>
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#include <symbol/kallsyms.h>
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#include <sys/utsname.h>
P
Peter Zijlstra 已提交
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static int dso__load_kernel_sym(struct dso *dso, struct map *map,
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				symbol_filter_t filter);
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static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
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			symbol_filter_t filter);
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int vmlinux_path__nr_entries;
char **vmlinux_path;
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struct symbol_conf symbol_conf = {
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	.use_modules	  = true,
	.try_vmlinux_path = true,
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	.annotate_src	  = true,
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	.demangle	  = true,
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	.symfs            = "",
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};

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static enum dso_binary_type binary_type_symtab[] = {
	DSO_BINARY_TYPE__KALLSYMS,
	DSO_BINARY_TYPE__GUEST_KALLSYMS,
	DSO_BINARY_TYPE__JAVA_JIT,
	DSO_BINARY_TYPE__DEBUGLINK,
	DSO_BINARY_TYPE__BUILD_ID_CACHE,
	DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
	DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
	DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
	DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
	DSO_BINARY_TYPE__GUEST_KMODULE,
	DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
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	DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
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	DSO_BINARY_TYPE__NOT_FOUND,
};

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#define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
56

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bool symbol_type__is_a(char symbol_type, enum map_type map_type)
58
{
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	symbol_type = toupper(symbol_type);

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	switch (map_type) {
	case MAP__FUNCTION:
		return symbol_type == 'T' || symbol_type == 'W';
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	case MAP__VARIABLE:
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		return symbol_type == 'D';
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	default:
		return false;
	}
}

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

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

	return tail - str;
}

#define SYMBOL_A 0
#define SYMBOL_B 1

static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
{
	s64 a;
	s64 b;
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	size_t na, nb;
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	/* Prefer a symbol with non zero length */
	a = syma->end - syma->start;
	b = symb->end - symb->start;
	if ((b == 0) && (a > 0))
		return SYMBOL_A;
	else if ((a == 0) && (b > 0))
		return SYMBOL_B;

	/* Prefer a non weak symbol over a weak one */
	a = syma->binding == STB_WEAK;
	b = symb->binding == STB_WEAK;
	if (b && !a)
		return SYMBOL_A;
	if (a && !b)
		return SYMBOL_B;

	/* Prefer a global symbol over a non global one */
	a = syma->binding == STB_GLOBAL;
	b = symb->binding == STB_GLOBAL;
	if (a && !b)
		return SYMBOL_A;
	if (b && !a)
		return SYMBOL_B;

	/* Prefer a symbol with less underscores */
	a = prefix_underscores_count(syma->name);
	b = prefix_underscores_count(symb->name);
	if (b > a)
		return SYMBOL_A;
	else if (a > b)
		return SYMBOL_B;

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	/* Choose the symbol with the longest name */
	na = strlen(syma->name);
	nb = strlen(symb->name);
	if (na > nb)
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		return SYMBOL_A;
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	else if (na < nb)
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		return SYMBOL_B;
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	/* Avoid "SyS" kernel syscall aliases */
	if (na >= 3 && !strncmp(syma->name, "SyS", 3))
		return SYMBOL_B;
	if (na >= 10 && !strncmp(syma->name, "compat_SyS", 10))
		return SYMBOL_B;

	return SYMBOL_A;
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}

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void symbols__fixup_duplicate(struct rb_root *symbols)
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{
	struct rb_node *nd;
	struct symbol *curr, *next;

	nd = rb_first(symbols);

	while (nd) {
		curr = rb_entry(nd, struct symbol, rb_node);
again:
		nd = rb_next(&curr->rb_node);
		next = rb_entry(nd, struct symbol, rb_node);

		if (!nd)
			break;

		if (curr->start != next->start)
			continue;

		if (choose_best_symbol(curr, next) == SYMBOL_A) {
			rb_erase(&next->rb_node, symbols);
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			symbol__delete(next);
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			goto again;
		} else {
			nd = rb_next(&curr->rb_node);
			rb_erase(&curr->rb_node, symbols);
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			symbol__delete(curr);
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		}
	}
}

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void symbols__fixup_end(struct rb_root *symbols)
171
{
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	struct rb_node *nd, *prevnd = rb_first(symbols);
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	struct symbol *curr, *prev;
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	if (prevnd == NULL)
		return;

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	curr = rb_entry(prevnd, struct symbol, rb_node);

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	for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
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		prev = curr;
		curr = rb_entry(nd, struct symbol, rb_node);
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		if (prev->end == prev->start && prev->end != curr->start)
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			prev->end = curr->start - 1;
	}
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	/* Last entry */
	if (curr->end == curr->start)
		curr->end = roundup(curr->start, 4096);
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}

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void __map_groups__fixup_end(struct map_groups *mg, enum map_type type)
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{
	struct map *prev, *curr;
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	struct rb_node *nd, *prevnd = rb_first(&mg->maps[type]);
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	if (prevnd == NULL)
		return;

	curr = rb_entry(prevnd, struct map, rb_node);

	for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
		prev = curr;
		curr = rb_entry(nd, struct map, rb_node);
		prev->end = curr->start - 1;
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	}
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	/*
	 * We still haven't the actual symbols, so guess the
	 * last map final address.
	 */
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	curr->end = ~0ULL;
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}

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struct symbol *symbol__new(u64 start, u64 len, u8 binding, const char *name)
217
{
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	size_t namelen = strlen(name) + 1;
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	struct symbol *sym = calloc(1, (symbol_conf.priv_size +
					sizeof(*sym) + namelen));
	if (sym == NULL)
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		return NULL;

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	if (symbol_conf.priv_size)
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		sym = ((void *)sym) + symbol_conf.priv_size;
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	sym->start   = start;
	sym->end     = len ? start + len - 1 : start;
	sym->binding = binding;
	sym->namelen = namelen - 1;
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	pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
		  __func__, name, start, sym->end);
	memcpy(sym->name, name, namelen);
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	return sym;
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}

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void symbol__delete(struct symbol *sym)
240
{
241
	free(((void *)sym) - symbol_conf.priv_size);
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}

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size_t symbol__fprintf(struct symbol *sym, FILE *fp)
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{
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	return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %c %s\n",
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		       sym->start, sym->end,
		       sym->binding == STB_GLOBAL ? 'g' :
		       sym->binding == STB_LOCAL  ? 'l' : 'w',
		       sym->name);
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}

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size_t symbol__fprintf_symname_offs(const struct symbol *sym,
				    const struct addr_location *al, FILE *fp)
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{
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	unsigned long offset;
	size_t length;

	if (sym && sym->name) {
		length = fprintf(fp, "%s", sym->name);
		if (al) {
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			if (al->addr < sym->end)
				offset = al->addr - sym->start;
			else
				offset = al->addr - al->map->start - sym->start;
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			length += fprintf(fp, "+0x%lx", offset);
		}
		return length;
	} else
		return fprintf(fp, "[unknown]");
}
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size_t symbol__fprintf_symname(const struct symbol *sym, FILE *fp)
{
	return symbol__fprintf_symname_offs(sym, NULL, fp);
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}

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void symbols__delete(struct rb_root *symbols)
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{
	struct symbol *pos;
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	struct rb_node *next = rb_first(symbols);
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	while (next) {
		pos = rb_entry(next, struct symbol, rb_node);
		next = rb_next(&pos->rb_node);
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		rb_erase(&pos->rb_node, symbols);
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		symbol__delete(pos);
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	}
}

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void symbols__insert(struct rb_root *symbols, struct symbol *sym)
292
{
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	struct rb_node **p = &symbols->rb_node;
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	struct rb_node *parent = NULL;
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	const u64 ip = sym->start;
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	struct symbol *s;

	while (*p != NULL) {
		parent = *p;
		s = rb_entry(parent, struct symbol, rb_node);
		if (ip < s->start)
			p = &(*p)->rb_left;
		else
			p = &(*p)->rb_right;
	}
	rb_link_node(&sym->rb_node, parent, p);
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	rb_insert_color(&sym->rb_node, symbols);
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}

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static struct symbol *symbols__find(struct rb_root *symbols, u64 ip)
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{
	struct rb_node *n;

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	if (symbols == NULL)
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		return NULL;

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	n = symbols->rb_node;
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	while (n) {
		struct symbol *s = rb_entry(n, struct symbol, rb_node);

		if (ip < s->start)
			n = n->rb_left;
		else if (ip > s->end)
			n = n->rb_right;
		else
			return s;
	}

	return NULL;
}

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static struct symbol *symbols__first(struct rb_root *symbols)
{
	struct rb_node *n = rb_first(symbols);

	if (n)
		return rb_entry(n, struct symbol, rb_node);

	return NULL;
}

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struct symbol_name_rb_node {
	struct rb_node	rb_node;
	struct symbol	sym;
};

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static void symbols__insert_by_name(struct rb_root *symbols, struct symbol *sym)
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{
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	struct rb_node **p = &symbols->rb_node;
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	struct rb_node *parent = NULL;
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	struct symbol_name_rb_node *symn, *s;

	symn = container_of(sym, struct symbol_name_rb_node, sym);
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	while (*p != NULL) {
		parent = *p;
		s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
		if (strcmp(sym->name, s->sym.name) < 0)
			p = &(*p)->rb_left;
		else
			p = &(*p)->rb_right;
	}
	rb_link_node(&symn->rb_node, parent, p);
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	rb_insert_color(&symn->rb_node, symbols);
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}

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static void symbols__sort_by_name(struct rb_root *symbols,
				  struct rb_root *source)
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{
	struct rb_node *nd;

	for (nd = rb_first(source); nd; nd = rb_next(nd)) {
		struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
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		symbols__insert_by_name(symbols, pos);
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	}
}

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static struct symbol *symbols__find_by_name(struct rb_root *symbols,
					    const char *name)
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{
	struct rb_node *n;

384
	if (symbols == NULL)
385 386
		return NULL;

387
	n = symbols->rb_node;
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	while (n) {
		struct symbol_name_rb_node *s;
		int cmp;

		s = rb_entry(n, struct symbol_name_rb_node, rb_node);
		cmp = strcmp(name, s->sym.name);

		if (cmp < 0)
			n = n->rb_left;
		else if (cmp > 0)
			n = n->rb_right;
		else
			return &s->sym;
	}

	return NULL;
}

407
struct symbol *dso__find_symbol(struct dso *dso,
408
				enum map_type type, u64 addr)
409
{
410
	return symbols__find(&dso->symbols[type], addr);
411 412
}

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struct symbol *dso__first_symbol(struct dso *dso, enum map_type type)
{
	return symbols__first(&dso->symbols[type]);
}

418
struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type,
419 420
					const char *name)
{
421
	return symbols__find_by_name(&dso->symbol_names[type], name);
422 423
}

424
void dso__sort_by_name(struct dso *dso, enum map_type type)
425
{
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	dso__set_sorted_by_name(dso, type);
	return symbols__sort_by_name(&dso->symbol_names[type],
				     &dso->symbols[type]);
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}

431 432
size_t dso__fprintf_symbols_by_name(struct dso *dso,
				    enum map_type type, FILE *fp)
433 434 435 436 437
{
	size_t ret = 0;
	struct rb_node *nd;
	struct symbol_name_rb_node *pos;

438
	for (nd = rb_first(&dso->symbol_names[type]); nd; nd = rb_next(nd)) {
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		pos = rb_entry(nd, struct symbol_name_rb_node, rb_node);
		fprintf(fp, "%s\n", pos->sym.name);
	}

	return ret;
}

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int modules__parse(const char *filename, void *arg,
		   int (*process_module)(void *arg, const char *name,
					 u64 start))
{
	char *line = NULL;
	size_t n;
	FILE *file;
	int err = 0;

	file = fopen(filename, "r");
	if (file == NULL)
		return -1;

	while (1) {
		char name[PATH_MAX];
		u64 start;
		char *sep;
		ssize_t line_len;

		line_len = getline(&line, &n, file);
		if (line_len < 0) {
			if (feof(file))
				break;
			err = -1;
			goto out;
		}

		if (!line) {
			err = -1;
			goto out;
		}

		line[--line_len] = '\0'; /* \n */

		sep = strrchr(line, 'x');
		if (sep == NULL)
			continue;

		hex2u64(sep + 1, &start);

		sep = strchr(line, ' ');
		if (sep == NULL)
			continue;

		*sep = '\0';

		scnprintf(name, sizeof(name), "[%s]", line);

		err = process_module(arg, name, start);
		if (err)
			break;
	}
out:
	free(line);
	fclose(file);
	return err;
}

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struct process_kallsyms_args {
	struct map *map;
	struct dso *dso;
};

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bool symbol__is_idle(struct symbol *sym)
{
	const char * const idle_symbols[] = {
		"cpu_idle",
		"intel_idle",
		"default_idle",
		"native_safe_halt",
		"enter_idle",
		"exit_idle",
		"mwait_idle",
		"mwait_idle_with_hints",
		"poll_idle",
		"ppc64_runlatch_off",
		"pseries_dedicated_idle_sleep",
		NULL
	};

	int i;

	if (!sym)
		return false;

	for (i = 0; idle_symbols[i]; i++) {
		if (!strcmp(idle_symbols[i], sym->name))
			return true;
	}

	return false;
}

539
static int map__process_kallsym_symbol(void *arg, const char *name,
540
				       char type, u64 start)
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{
	struct symbol *sym;
	struct process_kallsyms_args *a = arg;
	struct rb_root *root = &a->dso->symbols[a->map->type];

	if (!symbol_type__is_a(type, a->map->type))
		return 0;

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	/*
	 * module symbols are not sorted so we add all
	 * symbols, setting length to 0, and rely on
	 * symbols__fixup_end() to fix it up.
	 */
	sym = symbol__new(start, 0, kallsyms2elf_type(type), name);
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	if (sym == NULL)
		return -ENOMEM;
	/*
	 * We will pass the symbols to the filter later, in
	 * map__split_kallsyms, when we have split the maps per module
	 */
	symbols__insert(root, sym);
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	return 0;
}

/*
 * Loads the function entries in /proc/kallsyms into kernel_map->dso,
 * so that we can in the next step set the symbol ->end address and then
 * call kernel_maps__split_kallsyms.
 */
571
static int dso__load_all_kallsyms(struct dso *dso, const char *filename,
572
				  struct map *map)
573
{
574
	struct process_kallsyms_args args = { .map = map, .dso = dso, };
575
	return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
576 577
}

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static int dso__split_kallsyms_for_kcore(struct dso *dso, struct map *map,
					 symbol_filter_t filter)
{
	struct map_groups *kmaps = map__kmap(map)->kmaps;
	struct map *curr_map;
	struct symbol *pos;
	int count = 0, moved = 0;
	struct rb_root *root = &dso->symbols[map->type];
	struct rb_node *next = rb_first(root);

	while (next) {
		char *module;

		pos = rb_entry(next, struct symbol, rb_node);
		next = rb_next(&pos->rb_node);

		module = strchr(pos->name, '\t');
		if (module)
			*module = '\0';

		curr_map = map_groups__find(kmaps, map->type, pos->start);

		if (!curr_map || (filter && filter(curr_map, pos))) {
			rb_erase(&pos->rb_node, root);
			symbol__delete(pos);
		} else {
			pos->start -= curr_map->start - curr_map->pgoff;
			if (pos->end)
				pos->end -= curr_map->start - curr_map->pgoff;
			if (curr_map != map) {
				rb_erase(&pos->rb_node, root);
				symbols__insert(
					&curr_map->dso->symbols[curr_map->type],
					pos);
				++moved;
			} else {
				++count;
			}
		}
	}

	/* Symbols have been adjusted */
	dso->adjust_symbols = 1;

	return count + moved;
}

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/*
 * Split the symbols into maps, making sure there are no overlaps, i.e. the
 * kernel range is broken in several maps, named [kernel].N, as we don't have
 * the original ELF section names vmlinux have.
 */
630
static int dso__split_kallsyms(struct dso *dso, struct map *map,
631
			       symbol_filter_t filter)
632
{
633
	struct map_groups *kmaps = map__kmap(map)->kmaps;
634
	struct machine *machine = kmaps->machine;
635
	struct map *curr_map = map;
636
	struct symbol *pos;
637
	int count = 0, moved = 0;	
638
	struct rb_root *root = &dso->symbols[map->type];
639
	struct rb_node *next = rb_first(root);
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	int kernel_range = 0;

	while (next) {
		char *module;

		pos = rb_entry(next, struct symbol, rb_node);
		next = rb_next(&pos->rb_node);

		module = strchr(pos->name, '\t');
		if (module) {
650
			if (!symbol_conf.use_modules)
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				goto discard_symbol;

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			*module++ = '\0';

655
			if (strcmp(curr_map->dso->short_name, module)) {
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				if (curr_map != map &&
657
				    dso->kernel == DSO_TYPE_GUEST_KERNEL &&
658
				    machine__is_default_guest(machine)) {
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					/*
					 * We assume all symbols of a module are
					 * continuous in * kallsyms, so curr_map
					 * points to a module and all its
					 * symbols are in its kmap. Mark it as
					 * loaded.
					 */
					dso__set_loaded(curr_map->dso,
							curr_map->type);
				}

				curr_map = map_groups__find_by_name(kmaps,
							map->type, module);
672
				if (curr_map == NULL) {
673
					pr_debug("%s/proc/{kallsyms,modules} "
674
					         "inconsistency while looking "
675
						 "for \"%s\" module!\n",
676
						 machine->root_dir, module);
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					curr_map = map;
					goto discard_symbol;
679
				}
680

681
				if (curr_map->dso->loaded &&
682
				    !machine__is_default_guest(machine))
683
					goto discard_symbol;
684
			}
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			/*
			 * So that we look just like we get from .ko files,
			 * i.e. not prelinked, relative to map->start.
			 */
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			pos->start = curr_map->map_ip(curr_map, pos->start);
			pos->end   = curr_map->map_ip(curr_map, pos->end);
		} else if (curr_map != map) {
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			char dso_name[PATH_MAX];
693
			struct dso *ndso;
694

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			if (count == 0) {
				curr_map = map;
				goto filter_symbol;
			}

700
			if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
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				snprintf(dso_name, sizeof(dso_name),
					"[guest.kernel].%d",
					kernel_range++);
			else
				snprintf(dso_name, sizeof(dso_name),
					"[kernel].%d",
					kernel_range++);
708

709 710
			ndso = dso__new(dso_name);
			if (ndso == NULL)
711 712
				return -1;

713
			ndso->kernel = dso->kernel;
714

715
			curr_map = map__new2(pos->start, ndso, map->type);
716
			if (curr_map == NULL) {
717
				dso__delete(ndso);
718 719
				return -1;
			}
720

721
			curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
722
			map_groups__insert(kmaps, curr_map);
723 724
			++kernel_range;
		}
725
filter_symbol:
726
		if (filter && filter(curr_map, pos)) {
727
discard_symbol:		rb_erase(&pos->rb_node, root);
728
			symbol__delete(pos);
729
		} else {
730 731 732
			if (curr_map != map) {
				rb_erase(&pos->rb_node, root);
				symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
733 734 735
				++moved;
			} else
				++count;
736
		}
737 738
	}

739
	if (curr_map != map &&
740
	    dso->kernel == DSO_TYPE_GUEST_KERNEL &&
741
	    machine__is_default_guest(kmaps->machine)) {
742 743 744
		dso__set_loaded(curr_map->dso, curr_map->type);
	}

745
	return count + moved;
746
}
747

748 749
bool symbol__restricted_filename(const char *filename,
				 const char *restricted_filename)
750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765
{
	bool restricted = false;

	if (symbol_conf.kptr_restrict) {
		char *r = realpath(filename, NULL);

		if (r != NULL) {
			restricted = strcmp(r, restricted_filename) == 0;
			free(r);
			return restricted;
		}
	}

	return restricted;
}

766 767 768 769
struct module_info {
	struct rb_node rb_node;
	char *name;
	u64 start;
770 771
};

772
static void add_module(struct module_info *mi, struct rb_root *modules)
773
{
774 775 776
	struct rb_node **p = &modules->rb_node;
	struct rb_node *parent = NULL;
	struct module_info *m;
777

778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798
	while (*p != NULL) {
		parent = *p;
		m = rb_entry(parent, struct module_info, rb_node);
		if (strcmp(mi->name, m->name) < 0)
			p = &(*p)->rb_left;
		else
			p = &(*p)->rb_right;
	}
	rb_link_node(&mi->rb_node, parent, p);
	rb_insert_color(&mi->rb_node, modules);
}

static void delete_modules(struct rb_root *modules)
{
	struct module_info *mi;
	struct rb_node *next = rb_first(modules);

	while (next) {
		mi = rb_entry(next, struct module_info, rb_node);
		next = rb_next(&mi->rb_node);
		rb_erase(&mi->rb_node, modules);
799
		zfree(&mi->name);
800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832
		free(mi);
	}
}

static struct module_info *find_module(const char *name,
				       struct rb_root *modules)
{
	struct rb_node *n = modules->rb_node;

	while (n) {
		struct module_info *m;
		int cmp;

		m = rb_entry(n, struct module_info, rb_node);
		cmp = strcmp(name, m->name);
		if (cmp < 0)
			n = n->rb_left;
		else if (cmp > 0)
			n = n->rb_right;
		else
			return m;
	}

	return NULL;
}

static int __read_proc_modules(void *arg, const char *name, u64 start)
{
	struct rb_root *modules = arg;
	struct module_info *mi;

	mi = zalloc(sizeof(struct module_info));
	if (!mi)
833 834
		return -ENOMEM;

835 836
	mi->name = strdup(name);
	mi->start = start;
837

838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856
	if (!mi->name) {
		free(mi);
		return -ENOMEM;
	}

	add_module(mi, modules);

	return 0;
}

static int read_proc_modules(const char *filename, struct rb_root *modules)
{
	if (symbol__restricted_filename(filename, "/proc/modules"))
		return -1;

	if (modules__parse(filename, modules, __read_proc_modules)) {
		delete_modules(modules);
		return -1;
	}
857 858 859 860

	return 0;
}

861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901
int compare_proc_modules(const char *from, const char *to)
{
	struct rb_root from_modules = RB_ROOT;
	struct rb_root to_modules = RB_ROOT;
	struct rb_node *from_node, *to_node;
	struct module_info *from_m, *to_m;
	int ret = -1;

	if (read_proc_modules(from, &from_modules))
		return -1;

	if (read_proc_modules(to, &to_modules))
		goto out_delete_from;

	from_node = rb_first(&from_modules);
	to_node = rb_first(&to_modules);
	while (from_node) {
		if (!to_node)
			break;

		from_m = rb_entry(from_node, struct module_info, rb_node);
		to_m = rb_entry(to_node, struct module_info, rb_node);

		if (from_m->start != to_m->start ||
		    strcmp(from_m->name, to_m->name))
			break;

		from_node = rb_next(from_node);
		to_node = rb_next(to_node);
	}

	if (!from_node && !to_node)
		ret = 0;

	delete_modules(&to_modules);
out_delete_from:
	delete_modules(&from_modules);

	return ret;
}

902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937
static int do_validate_kcore_modules(const char *filename, struct map *map,
				  struct map_groups *kmaps)
{
	struct rb_root modules = RB_ROOT;
	struct map *old_map;
	int err;

	err = read_proc_modules(filename, &modules);
	if (err)
		return err;

	old_map = map_groups__first(kmaps, map->type);
	while (old_map) {
		struct map *next = map_groups__next(old_map);
		struct module_info *mi;

		if (old_map == map || old_map->start == map->start) {
			/* The kernel map */
			old_map = next;
			continue;
		}

		/* Module must be in memory at the same address */
		mi = find_module(old_map->dso->short_name, &modules);
		if (!mi || mi->start != old_map->start) {
			err = -EINVAL;
			goto out;
		}

		old_map = next;
	}
out:
	delete_modules(&modules);
	return err;
}

938
/*
939
 * If kallsyms is referenced by name then we look for filename in the same
940 941
 * directory.
 */
942 943 944
static bool filename_from_kallsyms_filename(char *filename,
					    const char *base_name,
					    const char *kallsyms_filename)
945 946 947
{
	char *name;

948 949
	strcpy(filename, kallsyms_filename);
	name = strrchr(filename, '/');
950 951 952
	if (!name)
		return false;

953 954 955 956
	name += 1;

	if (!strcmp(name, "kallsyms")) {
		strcpy(name, base_name);
957 958 959 960 961 962
		return true;
	}

	return false;
}

963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978
static int validate_kcore_modules(const char *kallsyms_filename,
				  struct map *map)
{
	struct map_groups *kmaps = map__kmap(map)->kmaps;
	char modules_filename[PATH_MAX];

	if (!filename_from_kallsyms_filename(modules_filename, "modules",
					     kallsyms_filename))
		return -EINVAL;

	if (do_validate_kcore_modules(modules_filename, map, kmaps))
		return -EINVAL;

	return 0;
}

979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995
static int validate_kcore_addresses(const char *kallsyms_filename,
				    struct map *map)
{
	struct kmap *kmap = map__kmap(map);

	if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
		u64 start;

		start = kallsyms__get_function_start(kallsyms_filename,
						     kmap->ref_reloc_sym->name);
		if (start != kmap->ref_reloc_sym->addr)
			return -EINVAL;
	}

	return validate_kcore_modules(kallsyms_filename, map);
}

996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018
struct kcore_mapfn_data {
	struct dso *dso;
	enum map_type type;
	struct list_head maps;
};

static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
{
	struct kcore_mapfn_data *md = data;
	struct map *map;

	map = map__new2(start, md->dso, md->type);
	if (map == NULL)
		return -ENOMEM;

	map->end = map->start + len;
	map->pgoff = pgoff;

	list_add(&map->node, &md->maps);

	return 0;
}

1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034
static int dso__load_kcore(struct dso *dso, struct map *map,
			   const char *kallsyms_filename)
{
	struct map_groups *kmaps = map__kmap(map)->kmaps;
	struct machine *machine = kmaps->machine;
	struct kcore_mapfn_data md;
	struct map *old_map, *new_map, *replacement_map = NULL;
	bool is_64_bit;
	int err, fd;
	char kcore_filename[PATH_MAX];
	struct symbol *sym;

	/* This function requires that the map is the kernel map */
	if (map != machine->vmlinux_maps[map->type])
		return -EINVAL;

1035 1036 1037 1038
	if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
					     kallsyms_filename))
		return -EINVAL;

1039 1040
	/* Modules and kernel must be present at their original addresses */
	if (validate_kcore_addresses(kallsyms_filename, map))
1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108
		return -EINVAL;

	md.dso = dso;
	md.type = map->type;
	INIT_LIST_HEAD(&md.maps);

	fd = open(kcore_filename, O_RDONLY);
	if (fd < 0)
		return -EINVAL;

	/* Read new maps into temporary lists */
	err = file__read_maps(fd, md.type == MAP__FUNCTION, kcore_mapfn, &md,
			      &is_64_bit);
	if (err)
		goto out_err;

	if (list_empty(&md.maps)) {
		err = -EINVAL;
		goto out_err;
	}

	/* Remove old maps */
	old_map = map_groups__first(kmaps, map->type);
	while (old_map) {
		struct map *next = map_groups__next(old_map);

		if (old_map != map)
			map_groups__remove(kmaps, old_map);
		old_map = next;
	}

	/* Find the kernel map using the first symbol */
	sym = dso__first_symbol(dso, map->type);
	list_for_each_entry(new_map, &md.maps, node) {
		if (sym && sym->start >= new_map->start &&
		    sym->start < new_map->end) {
			replacement_map = new_map;
			break;
		}
	}

	if (!replacement_map)
		replacement_map = list_entry(md.maps.next, struct map, node);

	/* Add new maps */
	while (!list_empty(&md.maps)) {
		new_map = list_entry(md.maps.next, struct map, node);
		list_del(&new_map->node);
		if (new_map == replacement_map) {
			map->start	= new_map->start;
			map->end	= new_map->end;
			map->pgoff	= new_map->pgoff;
			map->map_ip	= new_map->map_ip;
			map->unmap_ip	= new_map->unmap_ip;
			map__delete(new_map);
			/* Ensure maps are correctly ordered */
			map_groups__remove(kmaps, map);
			map_groups__insert(kmaps, map);
		} else {
			map_groups__insert(kmaps, new_map);
		}
	}

	/*
	 * Set the data type and long name so that kcore can be read via
	 * dso__data_read_addr().
	 */
	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1109
		dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE;
1110
	else
1111
		dso->binary_type = DSO_BINARY_TYPE__KCORE;
1112
	dso__set_long_name(dso, strdup(kcore_filename), true);
1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132

	close(fd);

	if (map->type == MAP__FUNCTION)
		pr_debug("Using %s for kernel object code\n", kcore_filename);
	else
		pr_debug("Using %s for kernel data\n", kcore_filename);

	return 0;

out_err:
	while (!list_empty(&md.maps)) {
		map = list_entry(md.maps.next, struct map, node);
		list_del(&map->node);
		map__delete(map);
	}
	close(fd);
	return -EINVAL;
}

1133
int dso__load_kallsyms(struct dso *dso, const char *filename,
1134
		       struct map *map, symbol_filter_t filter)
1135
{
1136 1137 1138
	if (symbol__restricted_filename(filename, "/proc/kallsyms"))
		return -1;

1139
	if (dso__load_all_kallsyms(dso, filename, map) < 0)
1140 1141
		return -1;

1142
	symbols__fixup_duplicate(&dso->symbols[map->type]);
1143 1144
	symbols__fixup_end(&dso->symbols[map->type]);

1145
	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1146
		dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1147
	else
1148
		dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
1149

1150 1151 1152 1153
	if (!dso__load_kcore(dso, map, filename))
		return dso__split_kallsyms_for_kcore(dso, map, filter);
	else
		return dso__split_kallsyms(dso, map, filter);
1154 1155
}

1156
static int dso__load_perf_map(struct dso *dso, struct map *map,
1157
			      symbol_filter_t filter)
1158 1159 1160 1161 1162 1163
{
	char *line = NULL;
	size_t n;
	FILE *file;
	int nr_syms = 0;

1164
	file = fopen(dso->long_name, "r");
1165 1166 1167 1168
	if (file == NULL)
		goto out_failure;

	while (!feof(file)) {
1169
		u64 start, size;
1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193
		struct symbol *sym;
		int line_len, len;

		line_len = getline(&line, &n, file);
		if (line_len < 0)
			break;

		if (!line)
			goto out_failure;

		line[--line_len] = '\0'; /* \n */

		len = hex2u64(line, &start);

		len++;
		if (len + 2 >= line_len)
			continue;

		len += hex2u64(line + len, &size);

		len++;
		if (len + 2 >= line_len)
			continue;

1194
		sym = symbol__new(start, size, STB_GLOBAL, line + len);
1195 1196 1197 1198

		if (sym == NULL)
			goto out_delete_line;

1199
		if (filter && filter(map, sym))
1200
			symbol__delete(sym);
1201
		else {
1202
			symbols__insert(&dso->symbols[map->type], sym);
1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217
			nr_syms++;
		}
	}

	free(line);
	fclose(file);

	return nr_syms;

out_delete_line:
	free(line);
out_failure:
	return -1;
}

1218
int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
1219
{
1220
	char *name;
1221
	int ret = -1;
1222
	u_int i;
1223
	struct machine *machine;
1224
	char *root_dir = (char *) "";
1225 1226 1227
	int ss_pos = 0;
	struct symsrc ss_[2];
	struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
1228

1229
	dso__set_loaded(dso, map->type);
1230

1231 1232 1233 1234
	if (dso->kernel == DSO_TYPE_KERNEL)
		return dso__load_kernel_sym(dso, map, filter);
	else if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
		return dso__load_guest_kernel_sym(dso, map, filter);
1235

1236 1237
	if (map->groups && map->groups->machine)
		machine = map->groups->machine;
1238
	else
1239
		machine = NULL;
1240

1241
	dso->adjust_symbols = 0;
1242

1243
	if (strncmp(dso->name, "/tmp/perf-", 10) == 0) {
1244 1245
		struct stat st;

1246
		if (lstat(dso->name, &st) < 0)
1247 1248 1249 1250 1251 1252 1253 1254
			return -1;

		if (st.st_uid && (st.st_uid != geteuid())) {
			pr_warning("File %s not owned by current user or root, "
				"ignoring it.\n", dso->name);
			return -1;
		}

1255
		ret = dso__load_perf_map(dso, map, filter);
1256 1257
		dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
					     DSO_BINARY_TYPE__NOT_FOUND;
1258 1259 1260
		return ret;
	}

1261 1262 1263
	if (machine)
		root_dir = machine->root_dir;

1264 1265 1266 1267
	name = malloc(PATH_MAX);
	if (!name)
		return -1;

1268
	/* Iterate over candidate debug images.
1269 1270
	 * Keep track of "interesting" ones (those which have a symtab, dynsym,
	 * and/or opd section) for processing.
1271
	 */
1272
	for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
1273 1274
		struct symsrc *ss = &ss_[ss_pos];
		bool next_slot = false;
1275

1276
		enum dso_binary_type symtab_type = binary_type_symtab[i];
1277

1278 1279
		if (dso__read_binary_type_filename(dso, symtab_type,
						   root_dir, name, PATH_MAX))
1280
			continue;
1281 1282

		/* Name is now the name of the next image to try */
1283
		if (symsrc__init(ss, dso, name, symtab_type) < 0)
1284
			continue;
1285

1286 1287 1288
		if (!syms_ss && symsrc__has_symtab(ss)) {
			syms_ss = ss;
			next_slot = true;
1289 1290
			if (!dso->symsrc_filename)
				dso->symsrc_filename = strdup(name);
1291 1292
		}

1293 1294 1295
		if (!runtime_ss && symsrc__possibly_runtime(ss)) {
			runtime_ss = ss;
			next_slot = true;
1296
		}
1297

1298 1299
		if (next_slot) {
			ss_pos++;
1300

1301 1302
			if (syms_ss && runtime_ss)
				break;
1303
		}
1304

1305
	}
1306

1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317
	if (!runtime_ss && !syms_ss)
		goto out_free;

	if (runtime_ss && !syms_ss) {
		syms_ss = runtime_ss;
	}

	/* We'll have to hope for the best */
	if (!runtime_ss && syms_ss)
		runtime_ss = syms_ss;

1318 1319 1320 1321 1322 1323 1324
	if (syms_ss) {
		int km;

		km = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
		     dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE;
		ret = dso__load_sym(dso, map, syms_ss, runtime_ss, filter, km);
	} else {
1325
		ret = -1;
1326
	}
1327

1328
	if (ret > 0) {
1329 1330 1331 1332 1333
		int nr_plt;

		nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss, map, filter);
		if (nr_plt > 0)
			ret += nr_plt;
1334 1335
	}

1336 1337 1338
	for (; ss_pos > 0; ss_pos--)
		symsrc__destroy(&ss_[ss_pos - 1]);
out_free:
1339
	free(name);
1340
	if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
1341
		return 0;
1342 1343 1344
	return ret;
}

1345
struct map *map_groups__find_by_name(struct map_groups *mg,
1346
				     enum map_type type, const char *name)
1347 1348 1349
{
	struct rb_node *nd;

1350
	for (nd = rb_first(&mg->maps[type]); nd; nd = rb_next(nd)) {
1351 1352
		struct map *map = rb_entry(nd, struct map, rb_node);

1353
		if (map->dso && strcmp(map->dso->short_name, name) == 0)
1354 1355 1356 1357 1358 1359
			return map;
	}

	return NULL;
}

1360
int dso__load_vmlinux(struct dso *dso, struct map *map,
1361 1362
		      const char *vmlinux, bool vmlinux_allocated,
		      symbol_filter_t filter)
1363
{
1364 1365
	int err = -1;
	struct symsrc ss;
1366
	char symfs_vmlinux[PATH_MAX];
1367
	enum dso_binary_type symtab_type;
1368

1369 1370 1371 1372 1373
	if (vmlinux[0] == '/')
		snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
	else
		snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s%s",
			 symbol_conf.symfs, vmlinux);
1374

1375
	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1376
		symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1377
	else
1378
		symtab_type = DSO_BINARY_TYPE__VMLINUX;
1379

1380
	if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
1381 1382
		return -1;

1383
	err = dso__load_sym(dso, map, &ss, &ss, filter, 0);
1384
	symsrc__destroy(&ss);
1385

1386
	if (err > 0) {
1387
		if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1388
			dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1389
		else
1390
			dso->binary_type = DSO_BINARY_TYPE__VMLINUX;
1391
		dso__set_long_name(dso, vmlinux, vmlinux_allocated);
1392
		dso__set_loaded(dso, map->type);
1393
		pr_debug("Using %s for symbols\n", symfs_vmlinux);
1394
	}
1395

1396 1397 1398
	return err;
}

1399
int dso__load_vmlinux_path(struct dso *dso, struct map *map,
1400
			   symbol_filter_t filter)
1401 1402
{
	int i, err = 0;
1403
	char *filename;
1404 1405

	pr_debug("Looking at the vmlinux_path (%d entries long)\n",
1406 1407
		 vmlinux_path__nr_entries + 1);

1408
	filename = dso__build_id_filename(dso, NULL, 0);
1409
	if (filename != NULL) {
1410 1411
		err = dso__load_vmlinux(dso, map, filename, true, filter);
		if (err > 0)
1412 1413 1414
			goto out;
		free(filename);
	}
1415 1416

	for (i = 0; i < vmlinux_path__nr_entries; ++i) {
1417 1418
		err = dso__load_vmlinux(dso, map, vmlinux_path[i], false, filter);
		if (err > 0)
1419 1420
			break;
	}
1421
out:
1422 1423 1424
	return err;
}

1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443
static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
{
	char kallsyms_filename[PATH_MAX];
	struct dirent *dent;
	int ret = -1;
	DIR *d;

	d = opendir(dir);
	if (!d)
		return -1;

	while (1) {
		dent = readdir(d);
		if (!dent)
			break;
		if (dent->d_type != DT_DIR)
			continue;
		scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
			  "%s/%s/kallsyms", dir, dent->d_name);
1444
		if (!validate_kcore_addresses(kallsyms_filename, map)) {
1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476
			strlcpy(dir, kallsyms_filename, dir_sz);
			ret = 0;
			break;
		}
	}

	closedir(d);

	return ret;
}

static char *dso__find_kallsyms(struct dso *dso, struct map *map)
{
	u8 host_build_id[BUILD_ID_SIZE];
	char sbuild_id[BUILD_ID_SIZE * 2 + 1];
	bool is_host = false;
	char path[PATH_MAX];

	if (!dso->has_build_id) {
		/*
		 * Last resort, if we don't have a build-id and couldn't find
		 * any vmlinux file, try the running kernel kallsyms table.
		 */
		goto proc_kallsyms;
	}

	if (sysfs__read_build_id("/sys/kernel/notes", host_build_id,
				 sizeof(host_build_id)) == 0)
		is_host = dso__build_id_equal(dso, host_build_id);

	build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);

1477 1478 1479
	scnprintf(path, sizeof(path), "%s/[kernel.kcore]/%s", buildid_dir,
		  sbuild_id);

1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498
	/* Use /proc/kallsyms if possible */
	if (is_host) {
		DIR *d;
		int fd;

		/* If no cached kcore go with /proc/kallsyms */
		d = opendir(path);
		if (!d)
			goto proc_kallsyms;
		closedir(d);

		/*
		 * Do not check the build-id cache, until we know we cannot use
		 * /proc/kcore.
		 */
		fd = open("/proc/kcore", O_RDONLY);
		if (fd != -1) {
			close(fd);
			/* If module maps match go with /proc/kallsyms */
1499
			if (!validate_kcore_addresses("/proc/kallsyms", map))
1500 1501 1502 1503 1504 1505 1506 1507 1508 1509
				goto proc_kallsyms;
		}

		/* Find kallsyms in build-id cache with kcore */
		if (!find_matching_kcore(map, path, sizeof(path)))
			return strdup(path);

		goto proc_kallsyms;
	}

1510 1511 1512 1513
	/* Find kallsyms in build-id cache with kcore */
	if (!find_matching_kcore(map, path, sizeof(path)))
		return strdup(path);

1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528
	scnprintf(path, sizeof(path), "%s/[kernel.kallsyms]/%s",
		  buildid_dir, sbuild_id);

	if (access(path, F_OK)) {
		pr_err("No kallsyms or vmlinux with build-id %s was found\n",
		       sbuild_id);
		return NULL;
	}

	return strdup(path);

proc_kallsyms:
	return strdup("/proc/kallsyms");
}

1529
static int dso__load_kernel_sym(struct dso *dso, struct map *map,
1530
				symbol_filter_t filter)
1531
{
1532
	int err;
1533 1534
	const char *kallsyms_filename = NULL;
	char *kallsyms_allocated_filename = NULL;
1535
	/*
1536 1537
	 * Step 1: if the user specified a kallsyms or vmlinux filename, use
	 * it and only it, reporting errors to the user if it cannot be used.
1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549
	 *
	 * For instance, try to analyse an ARM perf.data file _without_ a
	 * build-id, or if the user specifies the wrong path to the right
	 * vmlinux file, obviously we can't fallback to another vmlinux (a
	 * x86_86 one, on the machine where analysis is being performed, say),
	 * or worse, /proc/kallsyms.
	 *
	 * If the specified file _has_ a build-id and there is a build-id
	 * section in the perf.data file, we will still do the expected
	 * validation in dso__load_vmlinux and will bail out if they don't
	 * match.
	 */
1550 1551 1552 1553 1554
	if (symbol_conf.kallsyms_name != NULL) {
		kallsyms_filename = symbol_conf.kallsyms_name;
		goto do_kallsyms;
	}

1555
	if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
1556 1557
		return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name,
					 false, filter);
1558
	}
1559

1560
	if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
1561
		err = dso__load_vmlinux_path(dso, map, filter);
1562
		if (err > 0)
1563
			return err;
1564 1565
	}

1566 1567 1568 1569
	/* do not try local files if a symfs was given */
	if (symbol_conf.symfs[0] != 0)
		return -1;

1570 1571 1572
	kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
	if (!kallsyms_allocated_filename)
		return -1;
1573

1574
	kallsyms_filename = kallsyms_allocated_filename;
1575

1576
do_kallsyms:
1577
	err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1578 1579
	if (err > 0)
		pr_debug("Using %s for symbols\n", kallsyms_filename);
1580
	free(kallsyms_allocated_filename);
1581

1582
	if (err > 0 && !dso__is_kcore(dso)) {
1583
		dso__set_long_name(dso, "[kernel.kallsyms]", false);
1584 1585
		map__fixup_start(map);
		map__fixup_end(map);
1586
	}
1587

1588 1589 1590
	return err;
}

1591 1592
static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
				      symbol_filter_t filter)
1593 1594 1595
{
	int err;
	const char *kallsyms_filename = NULL;
1596
	struct machine *machine;
1597 1598 1599 1600 1601 1602
	char path[PATH_MAX];

	if (!map->groups) {
		pr_debug("Guest kernel map hasn't the point to groups\n");
		return -1;
	}
1603
	machine = map->groups->machine;
1604

1605
	if (machine__is_default_guest(machine)) {
1606 1607 1608 1609 1610 1611
		/*
		 * if the user specified a vmlinux filename, use it and only
		 * it, reporting errors to the user if it cannot be used.
		 * Or use file guest_kallsyms inputted by user on commandline
		 */
		if (symbol_conf.default_guest_vmlinux_name != NULL) {
1612
			err = dso__load_vmlinux(dso, map,
1613 1614
						symbol_conf.default_guest_vmlinux_name,
						false, filter);
1615
			return err;
1616 1617 1618 1619 1620 1621
		}

		kallsyms_filename = symbol_conf.default_guest_kallsyms;
		if (!kallsyms_filename)
			return -1;
	} else {
1622
		sprintf(path, "%s/proc/kallsyms", machine->root_dir);
1623 1624 1625
		kallsyms_filename = path;
	}

1626
	err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1627
	if (err > 0)
1628
		pr_debug("Using %s for symbols\n", kallsyms_filename);
1629
	if (err > 0 && !dso__is_kcore(dso)) {
1630
		machine__mmap_name(machine, path, sizeof(path));
1631
		dso__set_long_name(dso, strdup(path), true);
1632 1633 1634 1635 1636 1637
		map__fixup_start(map);
		map__fixup_end(map);
	}

	return err;
}
1638

1639 1640
static void vmlinux_path__exit(void)
{
1641 1642
	while (--vmlinux_path__nr_entries >= 0)
		zfree(&vmlinux_path[vmlinux_path__nr_entries]);
1643

1644
	zfree(&vmlinux_path);
1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663
}

static int vmlinux_path__init(void)
{
	struct utsname uts;
	char bf[PATH_MAX];

	vmlinux_path = malloc(sizeof(char *) * 5);
	if (vmlinux_path == NULL)
		return -1;

	vmlinux_path[vmlinux_path__nr_entries] = strdup("vmlinux");
	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
		goto out_fail;
	++vmlinux_path__nr_entries;
	vmlinux_path[vmlinux_path__nr_entries] = strdup("/boot/vmlinux");
	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
		goto out_fail;
	++vmlinux_path__nr_entries;
1664 1665 1666 1667 1668 1669 1670 1671

	/* only try running kernel version if no symfs was given */
	if (symbol_conf.symfs[0] != 0)
		return 0;

	if (uname(&uts) < 0)
		return -1;

1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695
	snprintf(bf, sizeof(bf), "/boot/vmlinux-%s", uts.release);
	vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
		goto out_fail;
	++vmlinux_path__nr_entries;
	snprintf(bf, sizeof(bf), "/lib/modules/%s/build/vmlinux", uts.release);
	vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
		goto out_fail;
	++vmlinux_path__nr_entries;
	snprintf(bf, sizeof(bf), "/usr/lib/debug/lib/modules/%s/vmlinux",
		 uts.release);
	vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
		goto out_fail;
	++vmlinux_path__nr_entries;

	return 0;

out_fail:
	vmlinux_path__exit();
	return -1;
}

D
David Ahern 已提交
1696
int setup_list(struct strlist **list, const char *list_str,
1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709
		      const char *list_name)
{
	if (list_str == NULL)
		return 0;

	*list = strlist__new(true, list_str);
	if (!*list) {
		pr_err("problems parsing %s list\n", list_name);
		return -1;
	}
	return 0;
}

1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728
static bool symbol__read_kptr_restrict(void)
{
	bool value = false;

	if (geteuid() != 0) {
		FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
		if (fp != NULL) {
			char line[8];

			if (fgets(line, sizeof(line), fp) != NULL)
				value = atoi(line) != 0;

			fclose(fp);
		}
	}

	return value;
}

1729
int symbol__init(void)
1730
{
1731 1732
	const char *symfs;

1733 1734 1735
	if (symbol_conf.initialized)
		return 0;

1736
	symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
1737

1738 1739
	symbol__elf_init();

1740 1741 1742
	if (symbol_conf.sort_by_name)
		symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
					  sizeof(struct symbol));
1743

1744
	if (symbol_conf.try_vmlinux_path && vmlinux_path__init() < 0)
1745 1746
		return -1;

1747 1748 1749 1750 1751
	if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
		pr_err("'.' is the only non valid --field-separator argument\n");
		return -1;
	}

1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763
	if (setup_list(&symbol_conf.dso_list,
		       symbol_conf.dso_list_str, "dso") < 0)
		return -1;

	if (setup_list(&symbol_conf.comm_list,
		       symbol_conf.comm_list_str, "comm") < 0)
		goto out_free_dso_list;

	if (setup_list(&symbol_conf.sym_list,
		       symbol_conf.sym_list_str, "symbol") < 0)
		goto out_free_comm_list;

1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775
	/*
	 * A path to symbols of "/" is identical to ""
	 * reset here for simplicity.
	 */
	symfs = realpath(symbol_conf.symfs, NULL);
	if (symfs == NULL)
		symfs = symbol_conf.symfs;
	if (strcmp(symfs, "/") == 0)
		symbol_conf.symfs = "";
	if (symfs != symbol_conf.symfs)
		free((void *)symfs);

1776 1777
	symbol_conf.kptr_restrict = symbol__read_kptr_restrict();

1778
	symbol_conf.initialized = true;
1779
	return 0;
1780 1781 1782

out_free_comm_list:
	strlist__delete(symbol_conf.comm_list);
1783 1784
out_free_dso_list:
	strlist__delete(symbol_conf.dso_list);
1785
	return -1;
1786 1787
}

1788 1789
void symbol__exit(void)
{
1790 1791
	if (!symbol_conf.initialized)
		return;
1792 1793 1794 1795 1796
	strlist__delete(symbol_conf.sym_list);
	strlist__delete(symbol_conf.dso_list);
	strlist__delete(symbol_conf.comm_list);
	vmlinux_path__exit();
	symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
1797
	symbol_conf.initialized = false;
1798
}