Linux-2.6.33.2/tools/perf/util/symbol.c
#include "util.h"
#include "../perf.h"
#include "session.h"
#include "sort.h"
#include "string.h"
#include "symbol.h"
#include "thread.h"
#include "debug.h"
#include <asm/bug.h>
#include <libelf.h>
#include <gelf.h>
#include <elf.h>
#include <limits.h>
#include <sys/utsname.h>
#ifndef NT_GNU_BUILD_ID
#define NT_GNU_BUILD_ID 3
#endif
enum dso_origin {
DSO__ORIG_KERNEL = 0,
DSO__ORIG_JAVA_JIT,
DSO__ORIG_FEDORA,
DSO__ORIG_UBUNTU,
DSO__ORIG_BUILDID,
DSO__ORIG_DSO,
DSO__ORIG_KMODULE,
DSO__ORIG_NOT_FOUND,
};
static void dsos__add(struct list_head *head, struct dso *dso);
static struct map *map__new2(u64 start, struct dso *dso, enum map_type type);
static int dso__load_kernel_sym(struct dso *self, struct map *map,
struct perf_session *session, symbol_filter_t filter);
static int vmlinux_path__nr_entries;
static char **vmlinux_path;
struct symbol_conf symbol_conf = {
.exclude_other = true,
.use_modules = true,
.try_vmlinux_path = true,
};
bool dso__loaded(const struct dso *self, enum map_type type)
{
return self->loaded & (1 << type);
}
bool dso__sorted_by_name(const struct dso *self, enum map_type type)
{
return self->sorted_by_name & (1 << type);
}
static void dso__set_loaded(struct dso *self, enum map_type type)
{
self->loaded |= (1 << type);
}
static void dso__set_sorted_by_name(struct dso *self, enum map_type type)
{
self->sorted_by_name |= (1 << type);
}
static bool symbol_type__is_a(char symbol_type, enum map_type map_type)
{
switch (map_type) {
case MAP__FUNCTION:
return symbol_type == 'T' || symbol_type == 'W';
case MAP__VARIABLE:
return symbol_type == 'D' || symbol_type == 'd';
default:
return false;
}
}
static void symbols__fixup_end(struct rb_root *self)
{
struct rb_node *nd, *prevnd = rb_first(self);
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 - 1;
}
/* Last entry */
if (curr->end == curr->start)
curr->end = roundup(curr->start, 4096);
}
static void __map_groups__fixup_end(struct map_groups *self, enum map_type type)
{
struct map *prev, *curr;
struct rb_node *nd, *prevnd = rb_first(&self->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 = ~0UL;
}
static void map_groups__fixup_end(struct map_groups *self)
{
int i;
for (i = 0; i < MAP__NR_TYPES; ++i)
__map_groups__fixup_end(self, i);
}
static struct symbol *symbol__new(u64 start, u64 len, const char *name)
{
size_t namelen = strlen(name) + 1;
struct symbol *self = zalloc(symbol_conf.priv_size +
sizeof(*self) + namelen);
if (self == NULL)
return NULL;
if (symbol_conf.priv_size)
self = ((void *)self) + symbol_conf.priv_size;
self->start = start;
self->end = len ? start + len - 1 : start;
pr_debug3("%s: %s %#Lx-%#Lx\n", __func__, name, start, self->end);
memcpy(self->name, name, namelen);
return self;
}
void symbol__delete(struct symbol *self)
{
free(((void *)self) - symbol_conf.priv_size);
}
static size_t symbol__fprintf(struct symbol *self, FILE *fp)
{
return fprintf(fp, " %llx-%llx %s\n",
self->start, self->end, self->name);
}
static void dso__set_long_name(struct dso *self, char *name)
{
if (name == NULL)
return;
self->long_name = name;
self->long_name_len = strlen(name);
}
static void dso__set_basename(struct dso *self)
{
self->short_name = basename(self->long_name);
}
struct dso *dso__new(const char *name)
{
struct dso *self = malloc(sizeof(*self) + strlen(name) + 1);
if (self != NULL) {
int i;
strcpy(self->name, name);
dso__set_long_name(self, self->name);
self->short_name = self->name;
for (i = 0; i < MAP__NR_TYPES; ++i)
self->symbols[i] = self->symbol_names[i] = RB_ROOT;
self->slen_calculated = 0;
self->origin = DSO__ORIG_NOT_FOUND;
self->loaded = 0;
self->sorted_by_name = 0;
self->has_build_id = 0;
}
return self;
}
static void symbols__delete(struct rb_root *self)
{
struct symbol *pos;
struct rb_node *next = rb_first(self);
while (next) {
pos = rb_entry(next, struct symbol, rb_node);
next = rb_next(&pos->rb_node);
rb_erase(&pos->rb_node, self);
symbol__delete(pos);
}
}
void dso__delete(struct dso *self)
{
int i;
for (i = 0; i < MAP__NR_TYPES; ++i)
symbols__delete(&self->symbols[i]);
if (self->long_name != self->name)
free(self->long_name);
free(self);
}
void dso__set_build_id(struct dso *self, void *build_id)
{
memcpy(self->build_id, build_id, sizeof(self->build_id));
self->has_build_id = 1;
}
static void symbols__insert(struct rb_root *self, struct symbol *sym)
{
struct rb_node **p = &self->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, self);
}
static struct symbol *symbols__find(struct rb_root *self, u64 ip)
{
struct rb_node *n;
if (self == NULL)
return NULL;
n = self->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;
}
struct symbol_name_rb_node {
struct rb_node rb_node;
struct symbol sym;
};
static void symbols__insert_by_name(struct rb_root *self, struct symbol *sym)
{
struct rb_node **p = &self->rb_node;
struct rb_node *parent = NULL;
struct symbol_name_rb_node *symn = ((void *)sym) - sizeof(*parent), *s;
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, self);
}
static void symbols__sort_by_name(struct rb_root *self, 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(self, pos);
}
}
static struct symbol *symbols__find_by_name(struct rb_root *self, const char *name)
{
struct rb_node *n;
if (self == NULL)
return NULL;
n = self->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 *self,
enum map_type type, u64 addr)
{
return symbols__find(&self->symbols[type], addr);
}
struct symbol *dso__find_symbol_by_name(struct dso *self, enum map_type type,
const char *name)
{
return symbols__find_by_name(&self->symbol_names[type], name);
}
void dso__sort_by_name(struct dso *self, enum map_type type)
{
dso__set_sorted_by_name(self, type);
return symbols__sort_by_name(&self->symbol_names[type],
&self->symbols[type]);
}
int build_id__sprintf(u8 *self, int len, char *bf)
{
char *bid = bf;
u8 *raw = self;
int i;
for (i = 0; i < len; ++i) {
sprintf(bid, "%02x", *raw);
++raw;
bid += 2;
}
return raw - self;
}
size_t dso__fprintf_buildid(struct dso *self, FILE *fp)
{
char sbuild_id[BUILD_ID_SIZE * 2 + 1];
build_id__sprintf(self->build_id, sizeof(self->build_id), sbuild_id);
return fprintf(fp, "%s", sbuild_id);
}
size_t dso__fprintf(struct dso *self, enum map_type type, FILE *fp)
{
struct rb_node *nd;
size_t ret = fprintf(fp, "dso: %s (", self->short_name);
ret += dso__fprintf_buildid(self, fp);
ret += fprintf(fp, ")\n");
for (nd = rb_first(&self->symbols[type]); nd; nd = rb_next(nd)) {
struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
ret += symbol__fprintf(pos, fp);
}
return ret;
}
/*
* 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 *self, struct map *map)
{
char *line = NULL;
size_t n;
struct rb_root *root = &self->symbols[map->type];
FILE *file = fopen("/proc/kallsyms", "r");
if (file == NULL)
goto out_failure;
while (!feof(file)) {
u64 start;
struct symbol *sym;
int line_len, len;
char symbol_type;
char *symbol_name;
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;
symbol_type = toupper(line[len]);
if (!symbol_type__is_a(symbol_type, map->type))
continue;
symbol_name = line + len + 2;
/*
* Will fix up the end later, when we have all symbols sorted.
*/
sym = symbol__new(start, 0, symbol_name);
if (sym == NULL)
goto out_delete_line;
/*
* 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);
}
free(line);
fclose(file);
return 0;
out_delete_line:
free(line);
out_failure:
return -1;
}
/*
* 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 *self, struct map *map,
struct perf_session *session, symbol_filter_t filter)
{
struct map *curr_map = map;
struct symbol *pos;
int count = 0;
struct rb_root *root = &self->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(self->name, module)) {
curr_map = map_groups__find_by_name(&session->kmaps, map->type, module);
if (curr_map == NULL) {
pr_debug("/proc/{kallsyms,modules} "
"inconsistency!\n");
return -1;
}
}
/*
* 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 *dso;
snprintf(dso_name, sizeof(dso_name), "[kernel].%d",
kernel_range++);
dso = dso__new(dso_name);
if (dso == NULL)
return -1;
curr_map = map__new2(pos->start, dso, map->type);
if (curr_map == NULL) {
dso__delete(dso);
return -1;
}
curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
map_groups__insert(&session->kmaps, curr_map);
++kernel_range;
}
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);
}
count++;
}
}
return count;
}
static int dso__load_kallsyms(struct dso *self, struct map *map,
struct perf_session *session, symbol_filter_t filter)
{
if (dso__load_all_kallsyms(self, map) < 0)
return -1;
symbols__fixup_end(&self->symbols[map->type]);
self->origin = DSO__ORIG_KERNEL;
return dso__split_kallsyms(self, map, session, filter);
}
static int dso__load_perf_map(struct dso *self, struct map *map,
symbol_filter_t filter)
{
char *line = NULL;
size_t n;
FILE *file;
int nr_syms = 0;
file = fopen(self->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, line + len);
if (sym == NULL)
goto out_delete_line;
if (filter && filter(map, sym))
symbol__delete(sym);
else {
symbols__insert(&self->symbols[map->type], sym);
nr_syms++;
}
}
free(line);
fclose(file);
return nr_syms;
out_delete_line:
free(line);
out_failure:
return -1;
}
/**
* elf_symtab__for_each_symbol - iterate thru all the symbols
*
* @self: struct elf_symtab instance to iterate
* @idx: uint32_t idx
* @sym: GElf_Sym iterator
*/
#define elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) \
for (idx = 0, gelf_getsym(syms, idx, &sym);\
idx < nr_syms; \
idx++, gelf_getsym(syms, idx, &sym))
static inline uint8_t elf_sym__type(const GElf_Sym *sym)
{
return GELF_ST_TYPE(sym->st_info);
}
static inline int elf_sym__is_function(const GElf_Sym *sym)
{
return elf_sym__type(sym) == STT_FUNC &&
sym->st_name != 0 &&
sym->st_shndx != SHN_UNDEF;
}
static inline bool elf_sym__is_object(const GElf_Sym *sym)
{
return elf_sym__type(sym) == STT_OBJECT &&
sym->st_name != 0 &&
sym->st_shndx != SHN_UNDEF;
}
static inline int elf_sym__is_label(const GElf_Sym *sym)
{
return elf_sym__type(sym) == STT_NOTYPE &&
sym->st_name != 0 &&
sym->st_shndx != SHN_UNDEF &&
sym->st_shndx != SHN_ABS;
}
static inline const char *elf_sec__name(const GElf_Shdr *shdr,
const Elf_Data *secstrs)
{
return secstrs->d_buf + shdr->sh_name;
}
static inline int elf_sec__is_text(const GElf_Shdr *shdr,
const Elf_Data *secstrs)
{
return strstr(elf_sec__name(shdr, secstrs), "text") != NULL;
}
static inline bool elf_sec__is_data(const GElf_Shdr *shdr,
const Elf_Data *secstrs)
{
return strstr(elf_sec__name(shdr, secstrs), "data") != NULL;
}
static inline const char *elf_sym__name(const GElf_Sym *sym,
const Elf_Data *symstrs)
{
return symstrs->d_buf + sym->st_name;
}
static Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep,
GElf_Shdr *shp, const char *name,
size_t *idx)
{
Elf_Scn *sec = NULL;
size_t cnt = 1;
while ((sec = elf_nextscn(elf, sec)) != NULL) {
char *str;
gelf_getshdr(sec, shp);
str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name);
if (!strcmp(name, str)) {
if (idx)
*idx = cnt;
break;
}
++cnt;
}
return sec;
}
#define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \
for (idx = 0, pos = gelf_getrel(reldata, 0, &pos_mem); \
idx < nr_entries; \
++idx, pos = gelf_getrel(reldata, idx, &pos_mem))
#define elf_section__for_each_rela(reldata, pos, pos_mem, idx, nr_entries) \
for (idx = 0, pos = gelf_getrela(reldata, 0, &pos_mem); \
idx < nr_entries; \
++idx, pos = gelf_getrela(reldata, idx, &pos_mem))
/*
* We need to check if we have a .dynsym, so that we can handle the
* .plt, synthesizing its symbols, that aren't on the symtabs (be it
* .dynsym or .symtab).
* And always look at the original dso, not at debuginfo packages, that
* have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS).
*/
static int dso__synthesize_plt_symbols(struct dso *self, struct map *map,
symbol_filter_t filter)
{
uint32_t nr_rel_entries, idx;
GElf_Sym sym;
u64 plt_offset;
GElf_Shdr shdr_plt;
struct symbol *f;
GElf_Shdr shdr_rel_plt, shdr_dynsym;
Elf_Data *reldata, *syms, *symstrs;
Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym;
size_t dynsym_idx;
GElf_Ehdr ehdr;
char sympltname[1024];
Elf *elf;
int nr = 0, symidx, fd, err = 0;
fd = open(self->long_name, O_RDONLY);
if (fd < 0)
goto out;
elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
if (elf == NULL)
goto out_close;
if (gelf_getehdr(elf, &ehdr) == NULL)
goto out_elf_end;
scn_dynsym = elf_section_by_name(elf, &ehdr, &shdr_dynsym,
".dynsym", &dynsym_idx);
if (scn_dynsym == NULL)
goto out_elf_end;
scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
".rela.plt", NULL);
if (scn_plt_rel == NULL) {
scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt,
".rel.plt", NULL);
if (scn_plt_rel == NULL)
goto out_elf_end;
}
err = -1;
if (shdr_rel_plt.sh_link != dynsym_idx)
goto out_elf_end;
if (elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL) == NULL)
goto out_elf_end;
/*
* Fetch the relocation section to find the idxes to the GOT
* and the symbols in the .dynsym they refer to.
*/
reldata = elf_getdata(scn_plt_rel, NULL);
if (reldata == NULL)
goto out_elf_end;
syms = elf_getdata(scn_dynsym, NULL);
if (syms == NULL)
goto out_elf_end;
scn_symstrs = elf_getscn(elf, shdr_dynsym.sh_link);
if (scn_symstrs == NULL)
goto out_elf_end;
symstrs = elf_getdata(scn_symstrs, NULL);
if (symstrs == NULL)
goto out_elf_end;
nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize;
plt_offset = shdr_plt.sh_offset;
if (shdr_rel_plt.sh_type == SHT_RELA) {
GElf_Rela pos_mem, *pos;
elf_section__for_each_rela(reldata, pos, pos_mem, idx,
nr_rel_entries) {
symidx = GELF_R_SYM(pos->r_info);
plt_offset += shdr_plt.sh_entsize;
gelf_getsym(syms, symidx, &sym);
snprintf(sympltname, sizeof(sympltname),
"%s@plt", elf_sym__name(&sym, symstrs));
f = symbol__new(plt_offset, shdr_plt.sh_entsize,
sympltname);
if (!f)
goto out_elf_end;
if (filter && filter(map, f))
symbol__delete(f);
else {
symbols__insert(&self->symbols[map->type], f);
++nr;
}
}
} else if (shdr_rel_plt.sh_type == SHT_REL) {
GElf_Rel pos_mem, *pos;
elf_section__for_each_rel(reldata, pos, pos_mem, idx,
nr_rel_entries) {
symidx = GELF_R_SYM(pos->r_info);
plt_offset += shdr_plt.sh_entsize;
gelf_getsym(syms, symidx, &sym);
snprintf(sympltname, sizeof(sympltname),
"%s@plt", elf_sym__name(&sym, symstrs));
f = symbol__new(plt_offset, shdr_plt.sh_entsize,
sympltname);
if (!f)
goto out_elf_end;
if (filter && filter(map, f))
symbol__delete(f);
else {
symbols__insert(&self->symbols[map->type], f);
++nr;
}
}
}
err = 0;
out_elf_end:
elf_end(elf);
out_close:
close(fd);
if (err == 0)
return nr;
out:
pr_warning("%s: problems reading %s PLT info.\n",
__func__, self->long_name);
return 0;
}
static bool elf_sym__is_a(GElf_Sym *self, enum map_type type)
{
switch (type) {
case MAP__FUNCTION:
return elf_sym__is_function(self);
case MAP__VARIABLE:
return elf_sym__is_object(self);
default:
return false;
}
}
static bool elf_sec__is_a(GElf_Shdr *self, Elf_Data *secstrs, enum map_type type)
{
switch (type) {
case MAP__FUNCTION:
return elf_sec__is_text(self, secstrs);
case MAP__VARIABLE:
return elf_sec__is_data(self, secstrs);
default:
return false;
}
}
static int dso__load_sym(struct dso *self, struct map *map,
struct perf_session *session, const char *name, int fd,
symbol_filter_t filter, int kernel, int kmodule)
{
struct map *curr_map = map;
struct dso *curr_dso = self;
size_t dso_name_len = strlen(self->short_name);
Elf_Data *symstrs, *secstrs;
uint32_t nr_syms;
int err = -1;
uint32_t idx;
GElf_Ehdr ehdr;
GElf_Shdr shdr;
Elf_Data *syms;
GElf_Sym sym;
Elf_Scn *sec, *sec_strndx;
Elf *elf;
int nr = 0;
elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
if (elf == NULL) {
pr_err("%s: cannot read %s ELF file.\n", __func__, name);
goto out_close;
}
if (gelf_getehdr(elf, &ehdr) == NULL) {
pr_err("%s: cannot get elf header.\n", __func__);
goto out_elf_end;
}
sec = elf_section_by_name(elf, &ehdr, &shdr, ".symtab", NULL);
if (sec == NULL) {
sec = elf_section_by_name(elf, &ehdr, &shdr, ".dynsym", NULL);
if (sec == NULL)
goto out_elf_end;
}
syms = elf_getdata(sec, NULL);
if (syms == NULL)
goto out_elf_end;
sec = elf_getscn(elf, shdr.sh_link);
if (sec == NULL)
goto out_elf_end;
symstrs = elf_getdata(sec, NULL);
if (symstrs == NULL)
goto out_elf_end;
sec_strndx = elf_getscn(elf, ehdr.e_shstrndx);
if (sec_strndx == NULL)
goto out_elf_end;
secstrs = elf_getdata(sec_strndx, NULL);
if (secstrs == NULL)
goto out_elf_end;
nr_syms = shdr.sh_size / shdr.sh_entsize;
memset(&sym, 0, sizeof(sym));
if (!kernel) {
self->adjust_symbols = (ehdr.e_type == ET_EXEC ||
elf_section_by_name(elf, &ehdr, &shdr,
".gnu.prelink_undo",
NULL) != NULL);
} else self->adjust_symbols = 0;
elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) {
struct symbol *f;
const char *elf_name;
char *demangled = NULL;
int is_label = elf_sym__is_label(&sym);
const char *section_name;
if (!is_label && !elf_sym__is_a(&sym, map->type))
continue;
sec = elf_getscn(elf, sym.st_shndx);
if (!sec)
goto out_elf_end;
gelf_getshdr(sec, &shdr);
if (is_label && !elf_sec__is_a(&shdr, secstrs, map->type))
continue;
elf_name = elf_sym__name(&sym, symstrs);
section_name = elf_sec__name(&shdr, secstrs);
if (kernel || kmodule) {
char dso_name[PATH_MAX];
if (strcmp(section_name,
curr_dso->short_name + dso_name_len) == 0)
goto new_symbol;
if (strcmp(section_name, ".text") == 0) {
curr_map = map;
curr_dso = self;
goto new_symbol;
}
snprintf(dso_name, sizeof(dso_name),
"%s%s", self->short_name, section_name);
curr_map = map_groups__find_by_name(&session->kmaps, map->type, dso_name);
if (curr_map == NULL) {
u64 start = sym.st_value;
if (kmodule)
start += map->start + shdr.sh_offset;
curr_dso = dso__new(dso_name);
if (curr_dso == NULL)
goto out_elf_end;
curr_map = map__new2(start, curr_dso,
MAP__FUNCTION);
if (curr_map == NULL) {
dso__delete(curr_dso);
goto out_elf_end;
}
curr_map->map_ip = identity__map_ip;
curr_map->unmap_ip = identity__map_ip;
curr_dso->origin = DSO__ORIG_KERNEL;
map_groups__insert(&session->kmaps, curr_map);
dsos__add(&dsos__kernel, curr_dso);
} else
curr_dso = curr_map->dso;
goto new_symbol;
}
if (curr_dso->adjust_symbols) {
pr_debug2("adjusting symbol: st_value: %Lx sh_addr: "
"%Lx sh_offset: %Lx\n", (u64)sym.st_value,
(u64)shdr.sh_addr, (u64)shdr.sh_offset);
sym.st_value -= shdr.sh_addr - shdr.sh_offset;
}
/*
* We need to figure out if the object was created from C++ sources
* DWARF DW_compile_unit has this, but we don't always have access
* to it...
*/
demangled = bfd_demangle(NULL, elf_name, DMGL_PARAMS | DMGL_ANSI);
if (demangled != NULL)
elf_name = demangled;
new_symbol:
f = symbol__new(sym.st_value, sym.st_size, elf_name);
free(demangled);
if (!f)
goto out_elf_end;
if (filter && filter(curr_map, f))
symbol__delete(f);
else {
symbols__insert(&curr_dso->symbols[curr_map->type], f);
nr++;
}
}
/*
* For misannotated, zeroed, ASM function sizes.
*/
if (nr > 0)
symbols__fixup_end(&self->symbols[map->type]);
err = nr;
out_elf_end:
elf_end(elf);
out_close:
return err;
}
static bool dso__build_id_equal(const struct dso *self, u8 *build_id)
{
return memcmp(self->build_id, build_id, sizeof(self->build_id)) == 0;
}
static bool __dsos__read_build_ids(struct list_head *head)
{
bool have_build_id = false;
struct dso *pos;
list_for_each_entry(pos, head, node)
if (filename__read_build_id(pos->long_name, pos->build_id,
sizeof(pos->build_id)) > 0) {
have_build_id = true;
pos->has_build_id = true;
}
return have_build_id;
}
bool dsos__read_build_ids(void)
{
bool kbuildids = __dsos__read_build_ids(&dsos__kernel),
ubuildids = __dsos__read_build_ids(&dsos__user);
return kbuildids || ubuildids;
}
/*
* Align offset to 4 bytes as needed for note name and descriptor data.
*/
#define NOTE_ALIGN(n) (((n) + 3) & -4U)
int filename__read_build_id(const char *filename, void *bf, size_t size)
{
int fd, err = -1;
GElf_Ehdr ehdr;
GElf_Shdr shdr;
Elf_Data *data;
Elf_Scn *sec;
Elf_Kind ek;
void *ptr;
Elf *elf;
if (size < BUILD_ID_SIZE)
goto out;
fd = open(filename, O_RDONLY);
if (fd < 0)
goto out;
elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
if (elf == NULL) {
pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename);
goto out_close;
}
ek = elf_kind(elf);
if (ek != ELF_K_ELF)
goto out_elf_end;
if (gelf_getehdr(elf, &ehdr) == NULL) {
pr_err("%s: cannot get elf header.\n", __func__);
goto out_elf_end;
}
sec = elf_section_by_name(elf, &ehdr, &shdr,
".note.gnu.build-id", NULL);
if (sec == NULL) {
sec = elf_section_by_name(elf, &ehdr, &shdr,
".notes", NULL);
if (sec == NULL)
goto out_elf_end;
}
data = elf_getdata(sec, NULL);
if (data == NULL)
goto out_elf_end;
ptr = data->d_buf;
while (ptr < (data->d_buf + data->d_size)) {
GElf_Nhdr *nhdr = ptr;
int namesz = NOTE_ALIGN(nhdr->n_namesz),
descsz = NOTE_ALIGN(nhdr->n_descsz);
const char *name;
ptr += sizeof(*nhdr);
name = ptr;
ptr += namesz;
if (nhdr->n_type == NT_GNU_BUILD_ID &&
nhdr->n_namesz == sizeof("GNU")) {
if (memcmp(name, "GNU", sizeof("GNU")) == 0) {
memcpy(bf, ptr, BUILD_ID_SIZE);
err = BUILD_ID_SIZE;
break;
}
}
ptr += descsz;
}
out_elf_end:
elf_end(elf);
out_close:
close(fd);
out:
return err;
}
int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
{
int fd, err = -1;
if (size < BUILD_ID_SIZE)
goto out;
fd = open(filename, O_RDONLY);
if (fd < 0)
goto out;
while (1) {
char bf[BUFSIZ];
GElf_Nhdr nhdr;
int namesz, descsz;
if (read(fd, &nhdr, sizeof(nhdr)) != sizeof(nhdr))
break;
namesz = NOTE_ALIGN(nhdr.n_namesz);
descsz = NOTE_ALIGN(nhdr.n_descsz);
if (nhdr.n_type == NT_GNU_BUILD_ID &&
nhdr.n_namesz == sizeof("GNU")) {
if (read(fd, bf, namesz) != namesz)
break;
if (memcmp(bf, "GNU", sizeof("GNU")) == 0) {
if (read(fd, build_id,
BUILD_ID_SIZE) == BUILD_ID_SIZE) {
err = 0;
break;
}
} else if (read(fd, bf, descsz) != descsz)
break;
} else {
int n = namesz + descsz;
if (read(fd, bf, n) != n)
break;
}
}
close(fd);
out:
return err;
}
char dso__symtab_origin(const struct dso *self)
{
static const char origin[] = {
[DSO__ORIG_KERNEL] = 'k',
[DSO__ORIG_JAVA_JIT] = 'j',
[DSO__ORIG_FEDORA] = 'f',
[DSO__ORIG_UBUNTU] = 'u',
[DSO__ORIG_BUILDID] = 'b',
[DSO__ORIG_DSO] = 'd',
[DSO__ORIG_KMODULE] = 'K',
};
if (self == NULL || self->origin == DSO__ORIG_NOT_FOUND)
return '!';
return origin[self->origin];
}
int dso__load(struct dso *self, struct map *map, struct perf_session *session,
symbol_filter_t filter)
{
int size = PATH_MAX;
char *name;
u8 build_id[BUILD_ID_SIZE];
int ret = -1;
int fd;
dso__set_loaded(self, map->type);
if (self->kernel)
return dso__load_kernel_sym(self, map, session, filter);
name = malloc(size);
if (!name)
return -1;
self->adjust_symbols = 0;
if (strncmp(self->name, "/tmp/perf-", 10) == 0) {
ret = dso__load_perf_map(self, map, filter);
self->origin = ret > 0 ? DSO__ORIG_JAVA_JIT :
DSO__ORIG_NOT_FOUND;
return ret;
}
self->origin = DSO__ORIG_FEDORA - 1;
more:
do {
self->origin++;
switch (self->origin) {
case DSO__ORIG_FEDORA:
snprintf(name, size, "/usr/lib/debug%s.debug",
self->long_name);
break;
case DSO__ORIG_UBUNTU:
snprintf(name, size, "/usr/lib/debug%s",
self->long_name);
break;
case DSO__ORIG_BUILDID:
if (filename__read_build_id(self->long_name, build_id,
sizeof(build_id))) {
char build_id_hex[BUILD_ID_SIZE * 2 + 1];
build_id__sprintf(build_id, sizeof(build_id),
build_id_hex);
snprintf(name, size,
"/usr/lib/debug/.build-id/%.2s/%s.debug",
build_id_hex, build_id_hex + 2);
if (self->has_build_id)
goto compare_build_id;
break;
}
self->origin++;
/* Fall thru */
case DSO__ORIG_DSO:
snprintf(name, size, "%s", self->long_name);
break;
default:
goto out;
}
if (self->has_build_id) {
if (filename__read_build_id(name, build_id,
sizeof(build_id)) < 0)
goto more;
compare_build_id:
if (!dso__build_id_equal(self, build_id))
goto more;
}
fd = open(name, O_RDONLY);
} while (fd < 0);
ret = dso__load_sym(self, map, NULL, name, fd, filter, 0, 0);
close(fd);
/*
* Some people seem to have debuginfo files _WITHOUT_ debug info!?!?
*/
if (!ret)
goto more;
if (ret > 0) {
int nr_plt = dso__synthesize_plt_symbols(self, map, filter);
if (nr_plt > 0)
ret += nr_plt;
}
out:
free(name);
if (ret < 0 && strstr(self->name, " (deleted)") != NULL)
return 0;
return ret;
}
struct map *map_groups__find_by_name(struct map_groups *self,
enum map_type type, const char *name)
{
struct rb_node *nd;
for (nd = rb_first(&self->maps[type]); nd; nd = rb_next(nd)) {
struct map *map = rb_entry(nd, struct map, rb_node);
if (map->dso && strcmp(map->dso->name, name) == 0)
return map;
}
return NULL;
}
static int perf_session__set_modules_path_dir(struct perf_session *self, char *dirname)
{
struct dirent *dent;
DIR *dir = opendir(dirname);
if (!dir) {
pr_debug("%s: cannot open %s dir\n", __func__, dirname);
return -1;
}
while ((dent = readdir(dir)) != NULL) {
char path[PATH_MAX];
if (dent->d_type == DT_DIR) {
if (!strcmp(dent->d_name, ".") ||
!strcmp(dent->d_name, ".."))
continue;
snprintf(path, sizeof(path), "%s/%s",
dirname, dent->d_name);
if (perf_session__set_modules_path_dir(self, path) < 0)
goto failure;
} else {
char *dot = strrchr(dent->d_name, '.'),
dso_name[PATH_MAX];
struct map *map;
char *long_name;
if (dot == NULL || strcmp(dot, ".ko"))
continue;
snprintf(dso_name, sizeof(dso_name), "[%.*s]",
(int)(dot - dent->d_name), dent->d_name);
strxfrchar(dso_name, '-', '_');
map = map_groups__find_by_name(&self->kmaps, MAP__FUNCTION, dso_name);
if (map == NULL)
continue;
snprintf(path, sizeof(path), "%s/%s",
dirname, dent->d_name);
long_name = strdup(path);
if (long_name == NULL)
goto failure;
dso__set_long_name(map->dso, long_name);
}
}
return 0;
failure:
closedir(dir);
return -1;
}
static int perf_session__set_modules_path(struct perf_session *self)
{
struct utsname uts;
char modules_path[PATH_MAX];
if (uname(&uts) < 0)
return -1;
snprintf(modules_path, sizeof(modules_path), "/lib/modules/%s/kernel",
uts.release);
return perf_session__set_modules_path_dir(self, modules_path);
}
/*
* Constructor variant for modules (where we know from /proc/modules where
* they are loaded) and for vmlinux, where only after we load all the
* symbols we'll know where it starts and ends.
*/
static struct map *map__new2(u64 start, struct dso *dso, enum map_type type)
{
struct map *self = malloc(sizeof(*self));
if (self != NULL) {
/*
* ->end will be filled after we load all the symbols
*/
map__init(self, type, start, 0, 0, dso);
}
return self;
}
static int perf_session__create_module_maps(struct perf_session *self)
{
char *line = NULL;
size_t n;
FILE *file = fopen("/proc/modules", "r");
struct map *map;
if (file == NULL)
return -1;
while (!feof(file)) {
char name[PATH_MAX];
u64 start;
struct dso *dso;
char *sep;
int line_len;
line_len = getline(&line, &n, file);
if (line_len < 0)
break;
if (!line)
goto out_failure;
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';
snprintf(name, sizeof(name), "[%s]", line);
dso = dso__new(name);
if (dso == NULL)
goto out_delete_line;
map = map__new2(start, dso, MAP__FUNCTION);
if (map == NULL) {
dso__delete(dso);
goto out_delete_line;
}
snprintf(name, sizeof(name),
"/sys/module/%s/notes/.note.gnu.build-id", line);
if (sysfs__read_build_id(name, dso->build_id,
sizeof(dso->build_id)) == 0)
dso->has_build_id = true;
dso->origin = DSO__ORIG_KMODULE;
map_groups__insert(&self->kmaps, map);
dsos__add(&dsos__kernel, dso);
}
free(line);
fclose(file);
return perf_session__set_modules_path(self);
out_delete_line:
free(line);
out_failure:
return -1;
}
static int dso__load_vmlinux(struct dso *self, struct map *map,
struct perf_session *session,
const char *vmlinux, symbol_filter_t filter)
{
int err = -1, fd;
if (self->has_build_id) {
u8 build_id[BUILD_ID_SIZE];
if (filename__read_build_id(vmlinux, build_id,
sizeof(build_id)) < 0) {
pr_debug("No build_id in %s, ignoring it\n", vmlinux);
return -1;
}
if (!dso__build_id_equal(self, build_id)) {
char expected_build_id[BUILD_ID_SIZE * 2 + 1],
vmlinux_build_id[BUILD_ID_SIZE * 2 + 1];
build_id__sprintf(self->build_id,
sizeof(self->build_id),
expected_build_id);
build_id__sprintf(build_id, sizeof(build_id),
vmlinux_build_id);
pr_debug("build_id in %s is %s while expected is %s, "
"ignoring it\n", vmlinux, vmlinux_build_id,
expected_build_id);
return -1;
}
}
fd = open(vmlinux, O_RDONLY);
if (fd < 0)
return -1;
dso__set_loaded(self, map->type);
err = dso__load_sym(self, map, session, self->long_name, fd, filter, 1, 0);
close(fd);
return err;
}
static int dso__load_kernel_sym(struct dso *self, struct map *map,
struct perf_session *session, symbol_filter_t filter)
{
int err;
bool is_kallsyms;
if (vmlinux_path != NULL) {
int i;
pr_debug("Looking at the vmlinux_path (%d entries long)\n",
vmlinux_path__nr_entries);
for (i = 0; i < vmlinux_path__nr_entries; ++i) {
err = dso__load_vmlinux(self, map, session,
vmlinux_path[i], filter);
if (err > 0) {
pr_debug("Using %s for symbols\n",
vmlinux_path[i]);
dso__set_long_name(self,
strdup(vmlinux_path[i]));
goto out_fixup;
}
}
}
is_kallsyms = self->long_name[0] == '[';
if (is_kallsyms)
goto do_kallsyms;
err = dso__load_vmlinux(self, map, session, self->long_name, filter);
if (err <= 0) {
pr_info("The file %s cannot be used, "
"trying to use /proc/kallsyms...", self->long_name);
do_kallsyms:
err = dso__load_kallsyms(self, map, session, filter);
if (err > 0 && !is_kallsyms)
dso__set_long_name(self, strdup("[kernel.kallsyms]"));
}
if (err > 0) {
out_fixup:
map__fixup_start(map);
map__fixup_end(map);
}
return err;
}
LIST_HEAD(dsos__user);
LIST_HEAD(dsos__kernel);
struct dso *vdso;
static void dsos__add(struct list_head *head, struct dso *dso)
{
list_add_tail(&dso->node, head);
}
static struct dso *dsos__find(struct list_head *head, const char *name)
{
struct dso *pos;
list_for_each_entry(pos, head, node)
if (strcmp(pos->name, name) == 0)
return pos;
return NULL;
}
struct dso *dsos__findnew(const char *name)
{
struct dso *dso = dsos__find(&dsos__user, name);
if (!dso) {
dso = dso__new(name);
if (dso != NULL) {
dsos__add(&dsos__user, dso);
dso__set_basename(dso);
}
}
return dso;
}
static void __dsos__fprintf(struct list_head *head, FILE *fp)
{
struct dso *pos;
list_for_each_entry(pos, head, node) {
int i;
for (i = 0; i < MAP__NR_TYPES; ++i)
dso__fprintf(pos, i, fp);
}
}
void dsos__fprintf(FILE *fp)
{
__dsos__fprintf(&dsos__kernel, fp);
__dsos__fprintf(&dsos__user, fp);
}
static size_t __dsos__fprintf_buildid(struct list_head *head, FILE *fp)
{
struct dso *pos;
size_t ret = 0;
list_for_each_entry(pos, head, node) {
ret += dso__fprintf_buildid(pos, fp);
ret += fprintf(fp, " %s\n", pos->long_name);
}
return ret;
}
size_t dsos__fprintf_buildid(FILE *fp)
{
return (__dsos__fprintf_buildid(&dsos__kernel, fp) +
__dsos__fprintf_buildid(&dsos__user, fp));
}
static struct dso *dsos__create_kernel( const char *vmlinux)
{
struct dso *kernel = dso__new(vmlinux ?: "[kernel.kallsyms]");
if (kernel == NULL)
return NULL;
kernel->short_name = "[kernel]";
kernel->kernel = 1;
vdso = dso__new("[vdso]");
if (vdso == NULL)
goto out_delete_kernel_dso;
dso__set_loaded(vdso, MAP__FUNCTION);
if (sysfs__read_build_id("/sys/kernel/notes", kernel->build_id,
sizeof(kernel->build_id)) == 0)
kernel->has_build_id = true;
dsos__add(&dsos__kernel, kernel);
dsos__add(&dsos__user, vdso);
return kernel;
out_delete_kernel_dso:
dso__delete(kernel);
return NULL;
}
static int map_groups__create_kernel_maps(struct map_groups *self, const char *vmlinux)
{
struct map *functions, *variables;
struct dso *kernel = dsos__create_kernel(vmlinux);
if (kernel == NULL)
return -1;
functions = map__new2(0, kernel, MAP__FUNCTION);
if (functions == NULL)
return -1;
variables = map__new2(0, kernel, MAP__VARIABLE);
if (variables == NULL) {
map__delete(functions);
return -1;
}
functions->map_ip = functions->unmap_ip =
variables->map_ip = variables->unmap_ip = identity__map_ip;
map_groups__insert(self, functions);
map_groups__insert(self, variables);
return 0;
}
static void vmlinux_path__exit(void)
{
while (--vmlinux_path__nr_entries >= 0) {
free(vmlinux_path[vmlinux_path__nr_entries]);
vmlinux_path[vmlinux_path__nr_entries] = NULL;
}
free(vmlinux_path);
vmlinux_path = NULL;
}
static int vmlinux_path__init(void)
{
struct utsname uts;
char bf[PATH_MAX];
if (uname(&uts) < 0)
return -1;
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;
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;
}
static 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;
}
int symbol__init(void)
{
elf_version(EV_CURRENT);
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;
return 0;
out_free_dso_list:
strlist__delete(symbol_conf.dso_list);
out_free_comm_list:
strlist__delete(symbol_conf.comm_list);
return -1;
}
int perf_session__create_kernel_maps(struct perf_session *self)
{
if (map_groups__create_kernel_maps(&self->kmaps,
symbol_conf.vmlinux_name) < 0)
return -1;
if (symbol_conf.use_modules &&
perf_session__create_module_maps(self) < 0)
pr_debug("Failed to load list of modules for session %s, "
"continuing...\n", self->filename);
/*
* Now that we have all the maps created, just set the ->end of them:
*/
map_groups__fixup_end(&self->kmaps);
return 0;
}