- 根目录:
- tools
- perf
- util
- symbol.c
#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>
#include <inttypes.h>
#include "build-id.h"
#include "util.h"
#include "debug.h"
#include "machine.h"
#include "symbol.h"
#include "strlist.h"
#include <elf.h>
#include <limits.h>
#include <symbol/kallsyms.h>
#include <sys/utsname.h>
static int dso__load_kernel_sym(struct dso *dso, struct map *map,
symbol_filter_t filter);
static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
symbol_filter_t filter);
int vmlinux_path__nr_entries;
char **vmlinux_path;
struct symbol_conf symbol_conf = {
.use_modules = true,
.try_vmlinux_path = true,
.annotate_src = true,
.demangle = true,
.symfs = "",
};
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,
DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
DSO_BINARY_TYPE__NOT_FOUND,
};
#define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
bool symbol_type__is_a(char symbol_type, enum map_type map_type)
{
symbol_type = toupper(symbol_type);
switch (map_type) {
case MAP__FUNCTION:
return symbol_type == 'T' || symbol_type == 'W';
case MAP__VARIABLE:
return symbol_type == 'D';
default:
return false;
}
}
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;
size_t na, nb;
/* 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;
/* Choose the symbol with the longest name */
na = strlen(syma->name);
nb = strlen(symb->name);
if (na > nb)
return SYMBOL_A;
else if (na < nb)
return SYMBOL_B;
/* 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;
}
void symbols__fixup_duplicate(struct rb_root *symbols)
{
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);
symbol__delete(next);
goto again;
} else {
nd = rb_next(&curr->rb_node);
rb_erase(&curr->rb_node, symbols);
symbol__delete(curr);
}
}
}
void symbols__fixup_end(struct rb_root *symbols)
{
struct rb_node *nd, *prevnd = rb_first(symbols);
struct symbol *curr, *prev;
if (prevnd == NULL)
return;
curr = rb_entry(prevnd, struct symbol, rb_node);
for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
prev = curr;
curr = rb_entry(nd, struct symbol, rb_node);
if (prev->end == prev->start && prev->end != curr->start)
prev->end = curr->start - 1;
}
/* Last entry */
if (curr->end == curr->start)
curr->end = roundup(curr->start, 4096);
}
void __map_groups__fixup_end(struct map_groups *mg, enum map_type type)
{
struct map *prev, *curr;
struct rb_node *nd, *prevnd = rb_first(&mg->maps[type]);
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;
}
/*
* We still haven't the actual symbols, so guess the
* last map final address.
*/
curr->end = ~0ULL;
}
struct symbol *symbol__new(u64 start, u64 len, u8 binding, const char *name)
{
size_t namelen = strlen(name) + 1;
struct symbol *sym = calloc(1, (symbol_conf.priv_size +
sizeof(*sym) + namelen));
if (sym == NULL)
return NULL;
if (symbol_conf.priv_size)
sym = ((void *)sym) + symbol_conf.priv_size;
sym->start = start;
sym->end = len ? start + len - 1 : start;
sym->binding = binding;
sym->namelen = namelen - 1;
pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
__func__, name, start, sym->end);
memcpy(sym->name, name, namelen);
return sym;
}
void symbol__delete(struct symbol *sym)
{
free(((void *)sym) - symbol_conf.priv_size);
}
size_t symbol__fprintf(struct symbol *sym, FILE *fp)
{
return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %c %s\n",
sym->start, sym->end,
sym->binding == STB_GLOBAL ? 'g' :
sym->binding == STB_LOCAL ? 'l' : 'w',
sym->name);
}
size_t symbol__fprintf_symname_offs(const struct symbol *sym,
const struct addr_location *al, FILE *fp)
{
unsigned long offset;
size_t length;
if (sym && sym->name) {
length = fprintf(fp, "%s", sym->name);
if (al) {
if (al->addr < sym->end)
offset = al->addr - sym->start;
else
offset = al->addr - al->map->start - sym->start;
length += fprintf(fp, "+0x%lx", offset);
}
return length;
} else
return fprintf(fp, "[unknown]");
}
size_t symbol__fprintf_symname(const struct symbol *sym, FILE *fp)
{
return symbol__fprintf_symname_offs(sym, NULL, fp);
}
void symbols__delete(struct rb_root *symbols)
{
struct symbol *pos;
struct rb_node *next = rb_first(symbols);
while (next) {
pos = rb_entry(next, struct symbol, rb_node);
next = rb_next(&pos->rb_node);
rb_erase(&pos->rb_node, symbols);
symbol__delete(pos);
}
}
void symbols__insert(struct rb_root *symbols, struct symbol *sym)
{
struct rb_node **p = &symbols->rb_node;
struct rb_node *parent = NULL;
const u64 ip = sym->start;
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);
rb_insert_color(&sym->rb_node, symbols);
}
static struct symbol *symbols__find(struct rb_root *symbols, u64 ip)
{
struct rb_node *n;
if (symbols == NULL)
return NULL;
n = symbols->rb_node;
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;
}
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;
}
struct symbol_name_rb_node {
struct rb_node rb_node;
struct symbol sym;
};
static void symbols__insert_by_name(struct rb_root *symbols, struct symbol *sym)
{
struct rb_node **p = &symbols->rb_node;
struct rb_node *parent = NULL;
struct symbol_name_rb_node *symn, *s;
symn = container_of(sym, struct symbol_name_rb_node, sym);
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);
rb_insert_color(&symn->rb_node, symbols);
}
static void symbols__sort_by_name(struct rb_root *symbols,
struct rb_root *source)
{
struct rb_node *nd;
for (nd = rb_first(source); nd; nd = rb_next(nd)) {
struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
symbols__insert_by_name(symbols, pos);
}
}
static struct symbol *symbols__find_by_name(struct rb_root *symbols,
const char *name)
{
struct rb_node *n;
if (symbols == NULL)
return NULL;
n = symbols->rb_node;
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;
}
struct symbol *dso__find_symbol(struct dso *dso,
enum map_type type, u64 addr)
{
return symbols__find(&dso->symbols[type], addr);
}
struct symbol *dso__first_symbol(struct dso *dso, enum map_type type)
{
return symbols__first(&dso->symbols[type]);
}
struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type,
const char *name)
{
return symbols__find_by_name(&dso->symbol_names[type], name);
}
void dso__sort_by_name(struct dso *dso, enum map_type type)
{
dso__set_sorted_by_name(dso, type);
return symbols__sort_by_name(&dso->symbol_names[type],
&dso->symbols[type]);
}
size_t dso__fprintf_symbols_by_name(struct dso *dso,
enum map_type type, FILE *fp)
{
size_t ret = 0;
struct rb_node *nd;
struct symbol_name_rb_node *pos;
for (nd = rb_first(&dso->symbol_names[type]); nd; nd = rb_next(nd)) {
pos = rb_entry(nd, struct symbol_name_rb_node, rb_node);
fprintf(fp, "%s\n", pos->sym.name);
}
return ret;
}
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;
}
struct process_kallsyms_args {
struct map *map;
struct dso *dso;
};
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;
}
static int map__process_kallsym_symbol(void *arg, const char *name,
char type, u64 start)
{
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;
/*
* 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);
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);
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.
*/
static int dso__load_all_kallsyms(struct dso *dso, const char *filename,
struct map *map)
{
struct process_kallsyms_args args = { .map = map, .dso = dso, };
return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
}
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;
}
/*
* 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.
*/
static int dso__split_kallsyms(struct dso *dso, struct map *map, u64 delta,
symbol_filter_t filter)
{
struct map_groups *kmaps = map__kmap(map)->kmaps;
struct machine *machine = kmaps->machine;
struct map *curr_map = map;
struct symbol *pos;
int count = 0, moved = 0;
struct rb_root *root = &dso->symbols[map->type];
struct rb_node *next = rb_first(root);
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) {
if (!symbol_conf.use_modules)
goto discard_symbol;
*module++ = '\0';
if (strcmp(curr_map->dso->short_name, module)) {
if (curr_map != map &&
dso->kernel == DSO_TYPE_GUEST_KERNEL &&
machine__is_default_guest(machine)) {
/*
* 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);
if (curr_map == NULL) {
pr_debug("%s/proc/{kallsyms,modules} "
"inconsistency while looking "
"for \"%s\" module!\n",
machine->root_dir, module);
curr_map = map;
goto discard_symbol;
}
if (curr_map->dso->loaded &&
!machine__is_default_guest(machine))
goto discard_symbol;
}
/*
* So that we look just like we get from .ko files,
* i.e. not prelinked, relative to map->start.
*/
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) {
char dso_name[PATH_MAX];
struct dso *ndso;
if (delta) {
/* Kernel was relocated at boot time */
pos->start -= delta;
pos->end -= delta;
}
if (count == 0) {
curr_map = map;
goto filter_symbol;
}
if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
snprintf(dso_name, sizeof(dso_name),
"[guest.kernel].%d",
kernel_range++);
else
snprintf(dso_name, sizeof(dso_name),
"[kernel].%d",
kernel_range++);
ndso = dso__new(dso_name);
if (ndso == NULL)
return -1;
ndso->kernel = dso->kernel;
curr_map = map__new2(pos->start, ndso, map->type);
if (curr_map == NULL) {
dso__delete(ndso);
return -1;
}
curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
map_groups__insert(kmaps, curr_map);
++kernel_range;
} else if (delta) {
/* Kernel was relocated at boot time */
pos->start -= delta;
pos->end -= delta;
}
filter_symbol:
if (filter && filter(curr_map, pos)) {
discard_symbol: rb_erase(&pos->rb_node, root);
symbol__delete(pos);
} else {
if (curr_map != map) {
rb_erase(&pos->rb_node, root);
symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
++moved;
} else
++count;
}
}
if (curr_map != map &&
dso->kernel == DSO_TYPE_GUEST_KERNEL &&
machine__is_default_guest(kmaps->machine)) {
dso__set_loaded(curr_map->dso, curr_map->type);
}
return count + moved;
}
bool symbol__restricted_filename(const char *filename,
const char *restricted_filename)
{
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;
}
struct module_info {
struct rb_node rb_node;
char *name;
u64 start;
};
static void add_module(struct module_info *mi, struct rb_root *modules)
{
struct rb_node **p = &modules->rb_node;
struct rb_node *parent = NULL;
struct module_info *m;
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);
zfree(&mi->name);
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)
return -ENOMEM;
mi->name = strdup(name);
mi->start = start;
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;
}
return 0;
}
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;
}
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;
}
/*
* If kallsyms is referenced by name then we look for filename in the same
* directory.
*/
static bool filename_from_kallsyms_filename(char *filename,
const char *base_name,
const char *kallsyms_filename)
{
char *name;
strcpy(filename, kallsyms_filename);
name = strrchr(filename, '/');
if (!name)
return false;
name += 1;
if (!strcmp(name, "kallsyms")) {
strcpy(name, base_name);
return true;
}
return false;
}
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;
}
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);
}
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;
}
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;
if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
kallsyms_filename))
return -EINVAL;
/* Modules and kernel must be present at their original addresses */
if (validate_kcore_addresses(kallsyms_filename, map))
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)
dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE;
else
dso->binary_type = DSO_BINARY_TYPE__KCORE;
dso__set_long_name(dso, strdup(kcore_filename), true);
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;
}
/*
* If the kernel is relocated at boot time, kallsyms won't match. Compute the
* delta based on the relocation reference symbol.
*/
static int kallsyms__delta(struct map *map, const char *filename, u64 *delta)
{
struct kmap *kmap = map__kmap(map);
u64 addr;
if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
return 0;
addr = kallsyms__get_function_start(filename,
kmap->ref_reloc_sym->name);
if (!addr)
return -1;
*delta = addr - kmap->ref_reloc_sym->addr;
return 0;
}
int dso__load_kallsyms(struct dso *dso, const char *filename,
struct map *map, symbol_filter_t filter)
{
u64 delta = 0;
if (symbol__restricted_filename(filename, "/proc/kallsyms"))
return -1;
if (dso__load_all_kallsyms(dso, filename, map) < 0)
return -1;
if (kallsyms__delta(map, filename, &delta))
return -1;
symbols__fixup_duplicate(&dso->symbols[map->type]);
symbols__fixup_end(&dso->symbols[map->type]);
if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
else
dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
if (!dso__load_kcore(dso, map, filename))
return dso__split_kallsyms_for_kcore(dso, map, filter);
else
return dso__split_kallsyms(dso, map, delta, filter);
}
static int dso__load_perf_map(struct dso *dso, struct map *map,
symbol_filter_t filter)
{
char *line = NULL;
size_t n;
FILE *file;
int nr_syms = 0;
file = fopen(dso->long_name, "r");
if (file == NULL)
goto out_failure;
while (!feof(file)) {
u64 start, size;
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;
sym = symbol__new(start, size, STB_GLOBAL, line + len);
if (sym == NULL)
goto out_delete_line;
if (filter && filter(map, sym))
symbol__delete(sym);
else {
symbols__insert(&dso->symbols[map->type], sym);
nr_syms++;
}
}
free(line);
fclose(file);
return nr_syms;
out_delete_line:
free(line);
out_failure:
return -1;
}
int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
{
char *name;
int ret = -1;
u_int i;
struct machine *machine;
char *root_dir = (char *) "";
int ss_pos = 0;
struct symsrc ss_[2];
struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
dso__set_loaded(dso, map->type);
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);
if (map->groups && map->groups->machine)
machine = map->groups->machine;
else
machine = NULL;
dso->adjust_symbols = 0;
if (strncmp(dso->name, "/tmp/perf-", 10) == 0) {
struct stat st;
if (lstat(dso->name, &st) < 0)
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;
}
ret = dso__load_perf_map(dso, map, filter);
dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
DSO_BINARY_TYPE__NOT_FOUND;
return ret;
}
if (machine)
root_dir = machine->root_dir;
name = malloc(PATH_MAX);
if (!name)
return -1;
/* Iterate over candidate debug images.
* Keep track of "interesting" ones (those which have a symtab, dynsym,
* and/or opd section) for processing.
*/
for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
struct symsrc *ss = &ss_[ss_pos];
bool next_slot = false;
enum dso_binary_type symtab_type = binary_type_symtab[i];
if (dso__read_binary_type_filename(dso, symtab_type,
root_dir, name, PATH_MAX))
continue;
/* Name is now the name of the next image to try */
if (symsrc__init(ss, dso, name, symtab_type) < 0)
continue;
if (!syms_ss && symsrc__has_symtab(ss)) {
syms_ss = ss;
next_slot = true;
if (!dso->symsrc_filename)
dso->symsrc_filename = strdup(name);
}
if (!runtime_ss && symsrc__possibly_runtime(ss)) {
runtime_ss = ss;
next_slot = true;
}
if (next_slot) {
ss_pos++;
if (syms_ss && runtime_ss)
break;
} else {
symsrc__destroy(ss);
}
}
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;
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 {
ret = -1;
}
if (ret > 0) {
int nr_plt;
nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss, map, filter);
if (nr_plt > 0)
ret += nr_plt;
}
for (; ss_pos > 0; ss_pos--)
symsrc__destroy(&ss_[ss_pos - 1]);
out_free:
free(name);
if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
return 0;
return ret;
}
struct map *map_groups__find_by_name(struct map_groups *mg,
enum map_type type, const char *name)
{
struct rb_node *nd;
for (nd = rb_first(&mg->maps[type]); nd; nd = rb_next(nd)) {
struct map *map = rb_entry(nd, struct map, rb_node);
if (map->dso && strcmp(map->dso->short_name, name) == 0)
return map;
}
return NULL;
}
int dso__load_vmlinux(struct dso *dso, struct map *map,
const char *vmlinux, bool vmlinux_allocated,
symbol_filter_t filter)
{
int err = -1;
struct symsrc ss;
char symfs_vmlinux[PATH_MAX];
enum dso_binary_type symtab_type;
if (vmlinux[0] == '/')
snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
else
snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s%s",
symbol_conf.symfs, vmlinux);
if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
else
symtab_type = DSO_BINARY_TYPE__VMLINUX;
if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
return -1;
err = dso__load_sym(dso, map, &ss, &ss, filter, 0);
symsrc__destroy(&ss);
if (err > 0) {
if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
else
dso->binary_type = DSO_BINARY_TYPE__VMLINUX;
dso__set_long_name(dso, vmlinux, vmlinux_allocated);
dso__set_loaded(dso, map->type);
pr_debug("Using %s for symbols\n", symfs_vmlinux);
}
return err;
}
int dso__load_vmlinux_path(struct dso *dso, struct map *map,
symbol_filter_t filter)
{
int i, err = 0;
char *filename;
pr_debug("Looking at the vmlinux_path (%d entries long)\n",
vmlinux_path__nr_entries + 1);
filename = dso__build_id_filename(dso, NULL, 0);
if (filename != NULL) {
err = dso__load_vmlinux(dso, map, filename, true, filter);
if (err > 0)
goto out;
free(filename);
}
for (i = 0; i < vmlinux_path__nr_entries; ++i) {
err = dso__load_vmlinux(dso, map, vmlinux_path[i], false, filter);
if (err > 0)
break;
}
out:
return err;
}
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);
if (!validate_kcore_addresses(kallsyms_filename, map)) {
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);
scnprintf(path, sizeof(path), "%s/[kernel.kcore]/%s", buildid_dir,
sbuild_id);
/* 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 */
if (!validate_kcore_addresses("/proc/kallsyms", map))
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;
}
/* Find kallsyms in build-id cache with kcore */
if (!find_matching_kcore(map, path, sizeof(path)))
return strdup(path);
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");
}
static int dso__load_kernel_sym(struct dso *dso, struct map *map,
symbol_filter_t filter)
{
int err;
const char *kallsyms_filename = NULL;
char *kallsyms_allocated_filename = NULL;
/*
* 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.
*
* 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.
*/
if (symbol_conf.kallsyms_name != NULL) {
kallsyms_filename = symbol_conf.kallsyms_name;
goto do_kallsyms;
}
if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name,
false, filter);
}
if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
err = dso__load_vmlinux_path(dso, map, filter);
if (err > 0)
return err;
}
/* do not try local files if a symfs was given */
if (symbol_conf.symfs[0] != 0)
return -1;
kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
if (!kallsyms_allocated_filename)
return -1;
kallsyms_filename = kallsyms_allocated_filename;
do_kallsyms:
err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
if (err > 0)
pr_debug("Using %s for symbols\n", kallsyms_filename);
free(kallsyms_allocated_filename);
if (err > 0 && !dso__is_kcore(dso)) {
dso__set_long_name(dso, "[kernel.kallsyms]", false);
map__fixup_start(map);
map__fixup_end(map);
}
return err;
}
static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
symbol_filter_t filter)
{
int err;
const char *kallsyms_filename = NULL;
struct machine *machine;
char path[PATH_MAX];
if (!map->groups) {
pr_debug("Guest kernel map hasn't the point to groups\n");
return -1;
}
machine = map->groups->machine;
if (machine__is_default_guest(machine)) {
/*
* 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) {
err = dso__load_vmlinux(dso, map,
symbol_conf.default_guest_vmlinux_name,
false, filter);
return err;
}
kallsyms_filename = symbol_conf.default_guest_kallsyms;
if (!kallsyms_filename)
return -1;
} else {
sprintf(path, "%s/proc/kallsyms", machine->root_dir);
kallsyms_filename = path;
}
err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
if (err > 0)
pr_debug("Using %s for symbols\n", kallsyms_filename);
if (err > 0 && !dso__is_kcore(dso)) {
machine__mmap_name(machine, path, sizeof(path));
dso__set_long_name(dso, strdup(path), true);
map__fixup_start(map);
map__fixup_end(map);
}
return err;
}
static void vmlinux_path__exit(void)
{
while (--vmlinux_path__nr_entries >= 0)
zfree(&vmlinux_path[vmlinux_path__nr_entries]);
zfree(&vmlinux_path);
}
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;
/* only try running kernel version if no symfs was given */
if (symbol_conf.symfs[0] != 0)
return 0;
if (uname(&uts) < 0)
return -1;
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;
}
int setup_list(struct strlist **list, const char *list_str,
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;
}
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;
}
int symbol__init(void)
{
const char *symfs;
if (symbol_conf.initialized)
return 0;
symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
symbol__elf_init();
if (symbol_conf.sort_by_name)
symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
sizeof(struct symbol));
if (symbol_conf.try_vmlinux_path && vmlinux_path__init() < 0)
return -1;
if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
pr_err("'.' is the only non valid --field-separator argument\n");
return -1;
}
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;
/*
* 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);
symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
symbol_conf.initialized = true;
return 0;
out_free_comm_list:
strlist__delete(symbol_conf.comm_list);
out_free_dso_list:
strlist__delete(symbol_conf.dso_list);
return -1;
}
void symbol__exit(void)
{
if (!symbol_conf.initialized)
return;
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;
symbol_conf.initialized = false;
}