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kernel-fxtec-pro1x/tools/perf/util/symbol.c
Arnaldo Carvalho de Melo 3b01a413c1 perf symbols: Improve kallsyms symbol end addr calculation 
For kallsyms we don't have the symbol address end, so we do an extra pass and
set the symbol end addr as being the start of the next minus one.

But this was being done just after we filtered the symbols of a
particular type (functions, variables), so the symbol end was sometimes
after what it really is.

Fixing up symbol end also was falling apart when we have symbol aliases,
then the end address of all but the last alias was being set to be
before its start.

Fix it up by checking for symbol aliases and making the kallsyms__parse
routine use the next symbol, whatever its type, as the limit for the
previous symbol, passing that end address to the callback.

This was detected by the 'perf test' synthetic paranoid regression
tests, fix it up so that even that case doesn't mislead us.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-12-22 20:31:45 -02:00

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#define _GNU_SOURCE
#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <libgen.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 "build-id.h"
#include "debug.h"
#include "symbol.h"
#include "strlist.h"
#include <libelf.h>
#include <gelf.h>
#include <elf.h>
#include <limits.h>
#include <sys/utsname.h>
#ifndef KSYM_NAME_LEN
#define KSYM_NAME_LEN 128
#endif
#ifndef NT_GNU_BUILD_ID
#define NT_GNU_BUILD_ID 3
#endif
static bool dso__build_id_equal(const struct dso *self, u8 *build_id);
static int elf_read_build_id(Elf *elf, void *bf, size_t size);
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,
symbol_filter_t filter);
static int dso__load_guest_kernel_sym(struct dso *self, struct map *map,
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,
.symfs = "",
};
int dso__name_len(const struct dso *self)
{
if (verbose)
return self->long_name_len;
return self->short_name_len;
}
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_sorted_by_name(struct dso *self, enum map_type type)
{
self->sorted_by_name |= (1 << type);
}
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)
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 = ~0ULL;
}
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, u8 binding,
const char *name)
{
size_t namelen = strlen(name) + 1;
struct symbol *self = calloc(1, (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;
self->binding = binding;
self->namelen = namelen - 1;
pr_debug4("%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 %c %s\n",
self->start, self->end,
self->binding == STB_GLOBAL ? 'g' :
self->binding == STB_LOCAL ? 'l' : 'w',
self->name);
}
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_short_name(struct dso *self, const char *name)
{
if (name == NULL)
return;
self->short_name = name;
self->short_name_len = strlen(name);
}
static void dso__set_basename(struct dso *self)
{
dso__set_short_name(self, basename(self->long_name));
}
struct dso *dso__new(const char *name)
{
struct dso *self = calloc(1, sizeof(*self) + strlen(name) + 1);
if (self != NULL) {
int i;
strcpy(self->name, name);
dso__set_long_name(self, self->name);
dso__set_short_name(self, 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;
self->kernel = DSO_TYPE_USER;
INIT_LIST_HEAD(&self->node);
}
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->sname_alloc)
free((char *)self->short_name);
if (self->lname_alloc)
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, *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, 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(const u8 *self, int len, char *bf)
{
char *bid = bf;
const 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_symbols_by_name(struct dso *self, enum map_type type, FILE *fp)
{
size_t ret = 0;
struct rb_node *nd;
struct symbol_name_rb_node *pos;
for (nd = rb_first(&self->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;
}
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);
if (self->short_name != self->long_name)
ret += fprintf(fp, "%s, ", self->long_name);
ret += fprintf(fp, "%s, %sloaded, ", map_type__name[type],
self->loaded ? "" : "NOT ");
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;
}
int kallsyms__parse(const char *filename, void *arg,
int (*process_symbol)(void *arg, const char *name,
char type, u64 start, u64 end))
{
char *line = NULL;
size_t n;
int err = -1;
u64 prev_start = 0;
char prev_symbol_type = 0;
char *prev_symbol_name;
FILE *file = fopen(filename, "r");
if (file == NULL)
goto out_failure;
prev_symbol_name = malloc(KSYM_NAME_LEN);
if (prev_symbol_name == NULL)
goto out_close;
err = 0;
while (!feof(file)) {
u64 start;
int line_len, len;
char symbol_type;
char *symbol_name;
line_len = getline(&line, &n, file);
if (line_len < 0 || !line)
break;
line[--line_len] = '\0'; /* \n */
len = hex2u64(line, &start);
len++;
if (len + 2 >= line_len)
continue;
symbol_type = toupper(line[len]);
len += 2;
symbol_name = line + len;
len = line_len - len;
if (len >= KSYM_NAME_LEN) {
err = -1;
break;
}
if (prev_symbol_type) {
u64 end = start;
if (end != prev_start)
--end;
err = process_symbol(arg, prev_symbol_name,
prev_symbol_type, prev_start, end);
if (err)
break;
}
memcpy(prev_symbol_name, symbol_name, len + 1);
prev_symbol_type = symbol_type;
prev_start = start;
}
free(prev_symbol_name);
free(line);
out_close:
fclose(file);
return err;
out_failure:
return -1;
}
struct process_kallsyms_args {
struct map *map;
struct dso *dso;
};
static u8 kallsyms2elf_type(char type)
{
if (type == 'W')
return STB_WEAK;
return isupper(type) ? STB_GLOBAL : STB_LOCAL;
}
static int map__process_kallsym_symbol(void *arg, const char *name,
char type, u64 start, u64 end)
{
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;
sym = symbol__new(start, end - start + 1,
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 *self, const char *filename,
struct map *map)
{
struct process_kallsyms_args args = { .map = map, .dso = self, };
return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
}
/*
* 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,
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 = &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(curr_map->dso->short_name, module)) {
if (curr_map != map &&
self->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 *dso;
if (count == 0) {
curr_map = map;
goto filter_symbol;
}
if (self->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++);
dso = dso__new(dso_name);
if (dso == NULL)
return -1;
dso->kernel = self->kernel;
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(kmaps, curr_map);
++kernel_range;
}
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 &&
self->kernel == DSO_TYPE_GUEST_KERNEL &&
machine__is_default_guest(kmaps->machine)) {
dso__set_loaded(curr_map->dso, curr_map->type);
}
return count + moved;
}
int dso__load_kallsyms(struct dso *self, const char *filename,
struct map *map, symbol_filter_t filter)
{
if (dso__load_all_kallsyms(self, filename, map) < 0)
return -1;
if (self->kernel == DSO_TYPE_GUEST_KERNEL)
self->origin = DSO__ORIG_GUEST_KERNEL;
else
self->origin = DSO__ORIG_KERNEL;
return dso__split_kallsyms(self, map, 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, STB_GLOBAL, 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;
char name[PATH_MAX];
snprintf(name, sizeof(name), "%s%s",
symbol_conf.symfs, self->long_name);
fd = open(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,
STB_GLOBAL, 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,
STB_GLOBAL, 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_debug("%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 size_t elf_addr_to_index(Elf *elf, GElf_Addr addr)
{
Elf_Scn *sec = NULL;
GElf_Shdr shdr;
size_t cnt = 1;
while ((sec = elf_nextscn(elf, sec)) != NULL) {
gelf_getshdr(sec, &shdr);
if ((addr >= shdr.sh_addr) &&
(addr < (shdr.sh_addr + shdr.sh_size)))
return cnt;
++cnt;
}
return -1;
}
static int dso__load_sym(struct dso *self, struct map *map, const char *name,
int fd, symbol_filter_t filter, int kmodule,
int want_symtab)
{
struct kmap *kmap = self->kernel ? map__kmap(map) : NULL;
struct map *curr_map = map;
struct dso *curr_dso = self;
Elf_Data *symstrs, *secstrs;
uint32_t nr_syms;
int err = -1;
uint32_t idx;
GElf_Ehdr ehdr;
GElf_Shdr shdr, opdshdr;
Elf_Data *syms, *opddata = NULL;
GElf_Sym sym;
Elf_Scn *sec, *sec_strndx, *opdsec;
Elf *elf;
int nr = 0;
size_t opdidx = 0;
elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL);
if (elf == NULL) {
pr_debug("%s: cannot read %s ELF file.\n", __func__, name);
goto out_close;
}
if (gelf_getehdr(elf, &ehdr) == NULL) {
pr_debug("%s: cannot get elf header.\n", __func__);
goto out_elf_end;
}
/* Always reject images with a mismatched build-id: */
if (self->has_build_id) {
u8 build_id[BUILD_ID_SIZE];
if (elf_read_build_id(elf, build_id,
BUILD_ID_SIZE) != BUILD_ID_SIZE)
goto out_elf_end;
if (!dso__build_id_equal(self, build_id))
goto out_elf_end;
}
sec = elf_section_by_name(elf, &ehdr, &shdr, ".symtab", NULL);
if (sec == NULL) {
if (want_symtab)
goto out_elf_end;
sec = elf_section_by_name(elf, &ehdr, &shdr, ".dynsym", NULL);
if (sec == NULL)
goto out_elf_end;
}
opdsec = elf_section_by_name(elf, &ehdr, &opdshdr, ".opd", &opdidx);
if (opdsec)
opddata = elf_rawdata(opdsec, NULL);
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 (self->kernel == DSO_TYPE_USER) {
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 = elf_sym__name(&sym, symstrs);
char *demangled = NULL;
int is_label = elf_sym__is_label(&sym);
const char *section_name;
if (kmap && kmap->ref_reloc_sym && kmap->ref_reloc_sym->name &&
strcmp(elf_name, kmap->ref_reloc_sym->name) == 0)
kmap->ref_reloc_sym->unrelocated_addr = sym.st_value;
if (!is_label && !elf_sym__is_a(&sym, map->type))
continue;
/* Reject ARM ELF "mapping symbols": these aren't unique and
* don't identify functions, so will confuse the profile
* output: */
if (ehdr.e_machine == EM_ARM) {
if (!strcmp(elf_name, "$a") ||
!strcmp(elf_name, "$d") ||
!strcmp(elf_name, "$t"))
continue;
}
if (opdsec && sym.st_shndx == opdidx) {
u32 offset = sym.st_value - opdshdr.sh_addr;
u64 *opd = opddata->d_buf + offset;
sym.st_value = *opd;
sym.st_shndx = elf_addr_to_index(elf, sym.st_value);
}
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;
section_name = elf_sec__name(&shdr, secstrs);
if (self->kernel != DSO_TYPE_USER || kmodule) {
char dso_name[PATH_MAX];
if (strcmp(section_name,
(curr_dso->short_name +
self->short_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(kmap->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_dso->kernel = self->kernel;
curr_map = map__new2(start, curr_dso,
map->type);
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 = self->origin;
map_groups__insert(kmap->kmaps, curr_map);
dsos__add(&self->node, curr_dso);
dso__set_loaded(curr_dso, map->type);
} else
curr_dso = curr_map->dso;
goto new_symbol;
}
if (curr_dso->adjust_symbols) {
pr_debug4("%s: adjusting symbol: st_value: %#Lx "
"sh_addr: %#Lx sh_offset: %#Lx\n", __func__,
(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,
GELF_ST_BIND(sym.st_info), 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]);
if (kmap) {
/*
* We need to fixup this here too because we create new
* maps here, for things like vsyscall sections.
*/
__map_groups__fixup_end(kmap->kmaps, 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;
}
bool __dsos__read_build_ids(struct list_head *head, bool with_hits)
{
bool have_build_id = false;
struct dso *pos;
list_for_each_entry(pos, head, node) {
if (with_hits && !pos->hit)
continue;
if (pos->has_build_id) {
have_build_id = true;
continue;
}
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;
}
/*
* Align offset to 4 bytes as needed for note name and descriptor data.
*/
#define NOTE_ALIGN(n) (((n) + 3) & -4U)
static int elf_read_build_id(Elf *elf, void *bf, size_t size)
{
int err = -1;
GElf_Ehdr ehdr;
GElf_Shdr shdr;
Elf_Data *data;
Elf_Scn *sec;
Elf_Kind ek;
void *ptr;
if (size < BUILD_ID_SIZE)
goto out;
ek = elf_kind(elf);
if (ek != ELF_K_ELF)
goto out;
if (gelf_getehdr(elf, &ehdr) == NULL) {
pr_err("%s: cannot get elf header.\n", __func__);
goto out;
}
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;
}
data = elf_getdata(sec, NULL);
if (data == NULL)
goto out;
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:
return err;
}
int filename__read_build_id(const char *filename, void *bf, size_t size)
{
int fd, err = -1;
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;
}
err = elf_read_build_id(elf, bf, size);
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_BUILD_ID_CACHE] = 'B',
[DSO__ORIG_FEDORA] = 'f',
[DSO__ORIG_UBUNTU] = 'u',
[DSO__ORIG_BUILDID] = 'b',
[DSO__ORIG_DSO] = 'd',
[DSO__ORIG_KMODULE] = 'K',
[DSO__ORIG_GUEST_KERNEL] = 'g',
[DSO__ORIG_GUEST_KMODULE] = 'G',
};
if (self == NULL || self->origin == DSO__ORIG_NOT_FOUND)
return '!';
return origin[self->origin];
}
int dso__load(struct dso *self, struct map *map, symbol_filter_t filter)
{
int size = PATH_MAX;
char *name;
int ret = -1;
int fd;
struct machine *machine;
const char *root_dir;
int want_symtab;
dso__set_loaded(self, map->type);
if (self->kernel == DSO_TYPE_KERNEL)
return dso__load_kernel_sym(self, map, filter);
else if (self->kernel == DSO_TYPE_GUEST_KERNEL)
return dso__load_guest_kernel_sym(self, map, filter);
if (map->groups && map->groups->machine)
machine = map->groups->machine;
else
machine = NULL;
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;
}
/* Iterate over candidate debug images.
* On the first pass, only load images if they have a full symtab.
* Failing that, do a second pass where we accept .dynsym also
*/
for (self->origin = DSO__ORIG_BUILD_ID_CACHE, want_symtab = 1;
self->origin != DSO__ORIG_NOT_FOUND;
self->origin++) {
switch (self->origin) {
case DSO__ORIG_BUILD_ID_CACHE:
/* skip the locally configured cache if a symfs is given */
if (symbol_conf.symfs[0] ||
(dso__build_id_filename(self, name, size) == NULL)) {
continue;
}
break;
case DSO__ORIG_FEDORA:
snprintf(name, size, "%s/usr/lib/debug%s.debug",
symbol_conf.symfs, self->long_name);
break;
case DSO__ORIG_UBUNTU:
snprintf(name, size, "%s/usr/lib/debug%s",
symbol_conf.symfs, self->long_name);
break;
case DSO__ORIG_BUILDID: {
char build_id_hex[BUILD_ID_SIZE * 2 + 1];
if (!self->has_build_id)
continue;
build_id__sprintf(self->build_id,
sizeof(self->build_id),
build_id_hex);
snprintf(name, size,
"%s/usr/lib/debug/.build-id/%.2s/%s.debug",
symbol_conf.symfs, build_id_hex, build_id_hex + 2);
}
break;
case DSO__ORIG_DSO:
snprintf(name, size, "%s%s",
symbol_conf.symfs, self->long_name);
break;
case DSO__ORIG_GUEST_KMODULE:
if (map->groups && map->groups->machine)
root_dir = map->groups->machine->root_dir;
else
root_dir = "";
snprintf(name, size, "%s%s%s", symbol_conf.symfs,
root_dir, self->long_name);
break;
case DSO__ORIG_KMODULE:
snprintf(name, size, "%s%s", symbol_conf.symfs,
self->long_name);
break;
default:
/*
* If we wanted a full symtab but no image had one,
* relax our requirements and repeat the search.
*/
if (want_symtab) {
want_symtab = 0;
self->origin = DSO__ORIG_BUILD_ID_CACHE;
} else
continue;
}
/* Name is now the name of the next image to try */
fd = open(name, O_RDONLY);
if (fd < 0)
continue;
ret = dso__load_sym(self, map, name, fd, filter, 0,
want_symtab);
close(fd);
/*
* Some people seem to have debuginfo files _WITHOUT_ debug
* info!?!?
*/
if (!ret)
continue;
if (ret > 0) {
int nr_plt = dso__synthesize_plt_symbols(self, map, filter);
if (nr_plt > 0)
ret += nr_plt;
break;
}
}
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->short_name, name) == 0)
return map;
}
return NULL;
}
static int dso__kernel_module_get_build_id(struct dso *self,
const char *root_dir)
{
char filename[PATH_MAX];
/*
* kernel module short names are of the form "[module]" and
* we need just "module" here.
*/
const char *name = self->short_name + 1;
snprintf(filename, sizeof(filename),
"%s/sys/module/%.*s/notes/.note.gnu.build-id",
root_dir, (int)strlen(name) - 1, name);
if (sysfs__read_build_id(filename, self->build_id,
sizeof(self->build_id)) == 0)
self->has_build_id = true;
return 0;
}
static int map_groups__set_modules_path_dir(struct map_groups *self,
const char *dir_name)
{
struct dirent *dent;
DIR *dir = opendir(dir_name);
int ret = 0;
if (!dir) {
pr_debug("%s: cannot open %s dir\n", __func__, dir_name);
return -1;
}
while ((dent = readdir(dir)) != NULL) {
char path[PATH_MAX];
struct stat st;
/*sshfs might return bad dent->d_type, so we have to stat*/
sprintf(path, "%s/%s", dir_name, dent->d_name);
if (stat(path, &st))
continue;
if (S_ISDIR(st.st_mode)) {
if (!strcmp(dent->d_name, ".") ||
!strcmp(dent->d_name, ".."))
continue;
snprintf(path, sizeof(path), "%s/%s",
dir_name, dent->d_name);
ret = map_groups__set_modules_path_dir(self, path);
if (ret < 0)
goto out;
} 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, MAP__FUNCTION, dso_name);
if (map == NULL)
continue;
snprintf(path, sizeof(path), "%s/%s",
dir_name, dent->d_name);
long_name = strdup(path);
if (long_name == NULL) {
ret = -1;
goto out;
}
dso__set_long_name(map->dso, long_name);
map->dso->lname_alloc = 1;
dso__kernel_module_get_build_id(map->dso, "");
}
}
out:
closedir(dir);
return ret;
}
static char *get_kernel_version(const char *root_dir)
{
char version[PATH_MAX];
FILE *file;
char *name, *tmp;
const char *prefix = "Linux version ";
sprintf(version, "%s/proc/version", root_dir);
file = fopen(version, "r");
if (!file)
return NULL;
version[0] = '\0';
tmp = fgets(version, sizeof(version), file);
fclose(file);
name = strstr(version, prefix);
if (!name)
return NULL;
name += strlen(prefix);
tmp = strchr(name, ' ');
if (tmp)
*tmp = '\0';
return strdup(name);
}
static int machine__set_modules_path(struct machine *self)
{
char *version;
char modules_path[PATH_MAX];
version = get_kernel_version(self->root_dir);
if (!version)
return -1;
snprintf(modules_path, sizeof(modules_path), "%s/lib/modules/%s/kernel",
self->root_dir, version);
free(version);
return map_groups__set_modules_path_dir(&self->kmaps, 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 = calloc(1, (sizeof(*self) +
(dso->kernel ? sizeof(struct kmap) : 0)));
if (self != NULL) {
/*
* ->end will be filled after we load all the symbols
*/
map__init(self, type, start, 0, 0, dso);
}
return self;
}
struct map *machine__new_module(struct machine *self, u64 start,
const char *filename)
{
struct map *map;
struct dso *dso = __dsos__findnew(&self->kernel_dsos, filename);
if (dso == NULL)
return NULL;
map = map__new2(start, dso, MAP__FUNCTION);
if (map == NULL)
return NULL;
if (machine__is_host(self))
dso->origin = DSO__ORIG_KMODULE;
else
dso->origin = DSO__ORIG_GUEST_KMODULE;
map_groups__insert(&self->kmaps, map);
return map;
}
static int machine__create_modules(struct machine *self)
{
char *line = NULL;
size_t n;
FILE *file;
struct map *map;
const char *modules;
char path[PATH_MAX];
if (machine__is_default_guest(self))
modules = symbol_conf.default_guest_modules;
else {
sprintf(path, "%s/proc/modules", self->root_dir);
modules = path;
}
file = fopen(modules, "r");
if (file == NULL)
return -1;
while (!feof(file)) {
char name[PATH_MAX];
u64 start;
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);
map = machine__new_module(self, start, name);
if (map == NULL)
goto out_delete_line;
dso__kernel_module_get_build_id(map->dso, self->root_dir);
}
free(line);
fclose(file);
return machine__set_modules_path(self);
out_delete_line:
free(line);
out_failure:
return -1;
}
static int dso__load_vmlinux(struct dso *self, struct map *map,
const char *vmlinux, symbol_filter_t filter)
{
int err = -1, fd;
char symfs_vmlinux[PATH_MAX];
snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s/%s",
symbol_conf.symfs, vmlinux);
fd = open(symfs_vmlinux, O_RDONLY);
if (fd < 0)
return -1;
dso__set_loaded(self, map->type);
err = dso__load_sym(self, map, symfs_vmlinux, fd, filter, 0, 0);
close(fd);
if (err > 0)
pr_debug("Using %s for symbols\n", symfs_vmlinux);
return err;
}
int dso__load_vmlinux_path(struct dso *self, 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(self, NULL, 0);
if (filename != NULL) {
err = dso__load_vmlinux(self, map, filename, filter);
if (err > 0) {
dso__set_long_name(self, filename);
goto out;
}
free(filename);
}
for (i = 0; i < vmlinux_path__nr_entries; ++i) {
err = dso__load_vmlinux(self, map, vmlinux_path[i], filter);
if (err > 0) {
dso__set_long_name(self, strdup(vmlinux_path[i]));
break;
}
}
out:
return err;
}
static int dso__load_kernel_sym(struct dso *self, 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.vmlinux_name != NULL) {
err = dso__load_vmlinux(self, map,
symbol_conf.vmlinux_name, filter);
if (err > 0) {
dso__set_long_name(self,
strdup(symbol_conf.vmlinux_name));
goto out_fixup;
}
return err;
}
if (vmlinux_path != NULL) {
err = dso__load_vmlinux_path(self, map, filter);
if (err > 0)
goto out_fixup;
}
/* do not try local files if a symfs was given */
if (symbol_conf.symfs[0] != 0)
return -1;
/*
* Say the kernel DSO was created when processing the build-id header table,
* we have a build-id, so check if it is the same as the running kernel,
* using it if it is.
*/
if (self->has_build_id) {
u8 kallsyms_build_id[BUILD_ID_SIZE];
char sbuild_id[BUILD_ID_SIZE * 2 + 1];
if (sysfs__read_build_id("/sys/kernel/notes", kallsyms_build_id,
sizeof(kallsyms_build_id)) == 0) {
if (dso__build_id_equal(self, kallsyms_build_id)) {
kallsyms_filename = "/proc/kallsyms";
goto do_kallsyms;
}
}
/*
* Now look if we have it on the build-id cache in
* $HOME/.debug/[kernel.kallsyms].
*/
build_id__sprintf(self->build_id, sizeof(self->build_id),
sbuild_id);
if (asprintf(&kallsyms_allocated_filename,
"%s/.debug/[kernel.kallsyms]/%s",
getenv("HOME"), sbuild_id) == -1) {
pr_err("Not enough memory for kallsyms file lookup\n");
return -1;
}
kallsyms_filename = kallsyms_allocated_filename;
if (access(kallsyms_filename, F_OK)) {
pr_err("No kallsyms or vmlinux with build-id %s "
"was found\n", sbuild_id);
free(kallsyms_allocated_filename);
return -1;
}
} else {
/*
* Last resort, if we don't have a build-id and couldn't find
* any vmlinux file, try the running kernel kallsyms table.
*/
kallsyms_filename = "/proc/kallsyms";
}
do_kallsyms:
err = dso__load_kallsyms(self, kallsyms_filename, map, filter);
if (err > 0)
pr_debug("Using %s for symbols\n", kallsyms_filename);
free(kallsyms_allocated_filename);
if (err > 0) {
out_fixup:
if (kallsyms_filename != NULL)
dso__set_long_name(self, strdup("[kernel.kallsyms]"));
map__fixup_start(map);
map__fixup_end(map);
}
return err;
}
static int dso__load_guest_kernel_sym(struct dso *self, 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(self, map,
symbol_conf.default_guest_vmlinux_name, filter);
goto out_try_fixup;
}
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(self, kallsyms_filename, map, filter);
if (err > 0)
pr_debug("Using %s for symbols\n", kallsyms_filename);
out_try_fixup:
if (err > 0) {
if (kallsyms_filename != NULL) {
machine__mmap_name(machine, path, sizeof(path));
dso__set_long_name(self, strdup(path));
}
map__fixup_start(map);
map__fixup_end(map);
}
return err;
}
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->long_name, name) == 0)
return pos;
return NULL;
}
struct dso *__dsos__findnew(struct list_head *head, const char *name)
{
struct dso *dso = dsos__find(head, name);
if (!dso) {
dso = dso__new(name);
if (dso != NULL) {
dsos__add(head, dso);
dso__set_basename(dso);
}
}
return dso;
}
size_t __dsos__fprintf(struct list_head *head, FILE *fp)
{
struct dso *pos;
size_t ret = 0;
list_for_each_entry(pos, head, node) {
int i;
for (i = 0; i < MAP__NR_TYPES; ++i)
ret += dso__fprintf(pos, i, fp);
}
return ret;
}
size_t machines__fprintf_dsos(struct rb_root *self, FILE *fp)
{
struct rb_node *nd;
size_t ret = 0;
for (nd = rb_first(self); nd; nd = rb_next(nd)) {
struct machine *pos = rb_entry(nd, struct machine, rb_node);
ret += __dsos__fprintf(&pos->kernel_dsos, fp);
ret += __dsos__fprintf(&pos->user_dsos, fp);
}
return ret;
}
static size_t __dsos__fprintf_buildid(struct list_head *head, FILE *fp,
bool with_hits)
{
struct dso *pos;
size_t ret = 0;
list_for_each_entry(pos, head, node) {
if (with_hits && !pos->hit)
continue;
ret += dso__fprintf_buildid(pos, fp);
ret += fprintf(fp, " %s\n", pos->long_name);
}
return ret;
}
size_t machine__fprintf_dsos_buildid(struct machine *self, FILE *fp, bool with_hits)
{
return __dsos__fprintf_buildid(&self->kernel_dsos, fp, with_hits) +
__dsos__fprintf_buildid(&self->user_dsos, fp, with_hits);
}
size_t machines__fprintf_dsos_buildid(struct rb_root *self, FILE *fp, bool with_hits)
{
struct rb_node *nd;
size_t ret = 0;
for (nd = rb_first(self); nd; nd = rb_next(nd)) {
struct machine *pos = rb_entry(nd, struct machine, rb_node);
ret += machine__fprintf_dsos_buildid(pos, fp, with_hits);
}
return ret;
}
struct dso *dso__new_kernel(const char *name)
{
struct dso *self = dso__new(name ?: "[kernel.kallsyms]");
if (self != NULL) {
dso__set_short_name(self, "[kernel]");
self->kernel = DSO_TYPE_KERNEL;
}
return self;
}
static struct dso *dso__new_guest_kernel(struct machine *machine,
const char *name)
{
char bf[PATH_MAX];
struct dso *self = dso__new(name ?: machine__mmap_name(machine, bf, sizeof(bf)));
if (self != NULL) {
dso__set_short_name(self, "[guest.kernel]");
self->kernel = DSO_TYPE_GUEST_KERNEL;
}
return self;
}
void dso__read_running_kernel_build_id(struct dso *self, struct machine *machine)
{
char path[PATH_MAX];
if (machine__is_default_guest(machine))
return;
sprintf(path, "%s/sys/kernel/notes", machine->root_dir);
if (sysfs__read_build_id(path, self->build_id,
sizeof(self->build_id)) == 0)
self->has_build_id = true;
}
static struct dso *machine__create_kernel(struct machine *self)
{
const char *vmlinux_name = NULL;
struct dso *kernel;
if (machine__is_host(self)) {
vmlinux_name = symbol_conf.vmlinux_name;
kernel = dso__new_kernel(vmlinux_name);
} else {
if (machine__is_default_guest(self))
vmlinux_name = symbol_conf.default_guest_vmlinux_name;
kernel = dso__new_guest_kernel(self, vmlinux_name);
}
if (kernel != NULL) {
dso__read_running_kernel_build_id(kernel, self);
dsos__add(&self->kernel_dsos, kernel);
}
return kernel;
}
struct process_args {
u64 start;
};
static int symbol__in_kernel(void *arg, const char *name,
char type __used, u64 start, u64 end __used)
{
struct process_args *args = arg;
if (strchr(name, '['))
return 0;
args->start = start;
return 1;
}
/* Figure out the start address of kernel map from /proc/kallsyms */
static u64 machine__get_kernel_start_addr(struct machine *machine)
{
const char *filename;
char path[PATH_MAX];
struct process_args args;
if (machine__is_host(machine)) {
filename = "/proc/kallsyms";
} else {
if (machine__is_default_guest(machine))
filename = (char *)symbol_conf.default_guest_kallsyms;
else {
sprintf(path, "%s/proc/kallsyms", machine->root_dir);
filename = path;
}
}
if (kallsyms__parse(filename, &args, symbol__in_kernel) <= 0)
return 0;
return args.start;
}
int __machine__create_kernel_maps(struct machine *self, struct dso *kernel)
{
enum map_type type;
u64 start = machine__get_kernel_start_addr(self);
for (type = 0; type < MAP__NR_TYPES; ++type) {
struct kmap *kmap;
self->vmlinux_maps[type] = map__new2(start, kernel, type);
if (self->vmlinux_maps[type] == NULL)
return -1;
self->vmlinux_maps[type]->map_ip =
self->vmlinux_maps[type]->unmap_ip = identity__map_ip;
kmap = map__kmap(self->vmlinux_maps[type]);
kmap->kmaps = &self->kmaps;
map_groups__insert(&self->kmaps, self->vmlinux_maps[type]);
}
return 0;
}
void machine__destroy_kernel_maps(struct machine *self)
{
enum map_type type;
for (type = 0; type < MAP__NR_TYPES; ++type) {
struct kmap *kmap;
if (self->vmlinux_maps[type] == NULL)
continue;
kmap = map__kmap(self->vmlinux_maps[type]);
map_groups__remove(&self->kmaps, self->vmlinux_maps[type]);
if (kmap->ref_reloc_sym) {
/*
* ref_reloc_sym is shared among all maps, so free just
* on one of them.
*/
if (type == MAP__FUNCTION) {
free((char *)kmap->ref_reloc_sym->name);
kmap->ref_reloc_sym->name = NULL;
free(kmap->ref_reloc_sym);
}
kmap->ref_reloc_sym = NULL;
}
map__delete(self->vmlinux_maps[type]);
self->vmlinux_maps[type] = NULL;
}
}
int machine__create_kernel_maps(struct machine *self)
{
struct dso *kernel = machine__create_kernel(self);
if (kernel == NULL ||
__machine__create_kernel_maps(self, kernel) < 0)
return -1;
if (symbol_conf.use_modules && machine__create_modules(self) < 0)
pr_debug("Problems creating module maps, continuing anyway...\n");
/*
* Now that we have all the maps created, just set the ->end of them:
*/
map_groups__fixup_end(&self->kmaps);
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];
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;
}
size_t machine__fprintf_vmlinux_path(struct machine *self, FILE *fp)
{
int i;
size_t printed = 0;
struct dso *kdso = self->vmlinux_maps[MAP__FUNCTION]->dso;
if (kdso->has_build_id) {
char filename[PATH_MAX];
if (dso__build_id_filename(kdso, filename, sizeof(filename)))
printed += fprintf(fp, "[0] %s\n", filename);
}
for (i = 0; i < vmlinux_path__nr_entries; ++i)
printed += fprintf(fp, "[%d] %s\n",
i + kdso->has_build_id, vmlinux_path[i]);
return printed;
}
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)
{
const char *symfs;
if (symbol_conf.initialized)
return 0;
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;
/*
* 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.initialized = true;
return 0;
out_free_dso_list:
strlist__delete(symbol_conf.dso_list);
out_free_comm_list:
strlist__delete(symbol_conf.comm_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;
}
int machines__create_kernel_maps(struct rb_root *self, pid_t pid)
{
struct machine *machine = machines__findnew(self, pid);
if (machine == NULL)
return -1;
return machine__create_kernel_maps(machine);
}
static int hex(char ch)
{
if ((ch >= '0') && (ch <= '9'))
return ch - '0';
if ((ch >= 'a') && (ch <= 'f'))
return ch - 'a' + 10;
if ((ch >= 'A') && (ch <= 'F'))
return ch - 'A' + 10;
return -1;
}
/*
* While we find nice hex chars, build a long_val.
* Return number of chars processed.
*/
int hex2u64(const char *ptr, u64 *long_val)
{
const char *p = ptr;
*long_val = 0;
while (*p) {
const int hex_val = hex(*p);
if (hex_val < 0)
break;
*long_val = (*long_val << 4) | hex_val;
p++;
}
return p - ptr;
}
char *strxfrchar(char *s, char from, char to)
{
char *p = s;
while ((p = strchr(p, from)) != NULL)
*p++ = to;
return s;
}
int machines__create_guest_kernel_maps(struct rb_root *self)
{
int ret = 0;
struct dirent **namelist = NULL;
int i, items = 0;
char path[PATH_MAX];
pid_t pid;
if (symbol_conf.default_guest_vmlinux_name ||
symbol_conf.default_guest_modules ||
symbol_conf.default_guest_kallsyms) {
machines__create_kernel_maps(self, DEFAULT_GUEST_KERNEL_ID);
}
if (symbol_conf.guestmount) {
items = scandir(symbol_conf.guestmount, &namelist, NULL, NULL);
if (items <= 0)
return -ENOENT;
for (i = 0; i < items; i++) {
if (!isdigit(namelist[i]->d_name[0])) {
/* Filter out . and .. */
continue;
}
pid = atoi(namelist[i]->d_name);
sprintf(path, "%s/%s/proc/kallsyms",
symbol_conf.guestmount,
namelist[i]->d_name);
ret = access(path, R_OK);
if (ret) {
pr_debug("Can't access file %s\n", path);
goto failure;
}
machines__create_kernel_maps(self, pid);
}
failure:
free(namelist);
}
return ret;
}
void machines__destroy_guest_kernel_maps(struct rb_root *self)
{
struct rb_node *next = rb_first(self);
while (next) {
struct machine *pos = rb_entry(next, struct machine, rb_node);
next = rb_next(&pos->rb_node);
rb_erase(&pos->rb_node, self);
machine__delete(pos);
}
}
int machine__load_kallsyms(struct machine *self, const char *filename,
enum map_type type, symbol_filter_t filter)
{
struct map *map = self->vmlinux_maps[type];
int ret = dso__load_kallsyms(map->dso, filename, map, filter);
if (ret > 0) {
dso__set_loaded(map->dso, type);
/*
* Since /proc/kallsyms will have multiple sessions for the
* kernel, with modules between them, fixup the end of all
* sections.
*/
__map_groups__fixup_end(&self->kmaps, type);
}
return ret;
}
int machine__load_vmlinux_path(struct machine *self, enum map_type type,
symbol_filter_t filter)
{
struct map *map = self->vmlinux_maps[type];
int ret = dso__load_vmlinux_path(map->dso, map, filter);
if (ret > 0) {
dso__set_loaded(map->dso, type);
map__reloc_vmlinux(map);
}
return ret;
}
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