linux-stable/tools/perf/util/map.c
Jiri Olsa cb8382e058 perf tools: Insert split maps correctly into origin group
When new maps are cloned out of split map they are added into origin
map's group, but their groups pointer is not updated.

This could lead to a segfault, because map->groups is expected to be
always set as reported by Markus:

  __map__is_kernel (map=map@entry=0x1abb7a0) at util/map.c:238
  238             return __machine__kernel_map(map->groups->machine, map->type) =
  (gdb) bt
  #0  __map__is_kernel (map=map@entry=0x1abb7a0) at util/map.c:238
  #1  0x00000000004393e4 in symbol_filter (map=map@entry=0x1abb7a0, sym=sym@entry
  #2  0x00000000004fcd4d in dso__load_sym (dso=dso@entry=0x166dae0, map=map@entry
  #3  0x00000000004a64e0 in dso__load (dso=0x166dae0, map=map@entry=0x1abb7a0, fi
  #4  0x00000000004b941f in map__load (filter=0x4393c0 <symbol_filter>, map=<opti
  #5  map__find_symbol (map=0x1abb7a0, addr=40188, filter=0x4393c0 <symbol_filter
  ...

Adding __map_groups__insert function to add map into groups together
with map->groups pointer update. It takes no lock as opposed to existing
map_groups__insert, as maps__fixup_overlappings(), where it is being
called, already has the necessary lock held.

Using __map_groups__insert to add new maps after map split.

Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20151104140811.GA32664@krava.brq.redhat.com
Fixes: cfc5acd4c8 ("perf top: Filter symbols based on __map__is_kernel(map)")
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-11-05 11:39:38 -03:00

855 lines
19 KiB
C

#include "symbol.h"
#include <errno.h>
#include <inttypes.h>
#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include "map.h"
#include "thread.h"
#include "strlist.h"
#include "vdso.h"
#include "build-id.h"
#include "util.h"
#include "debug.h"
#include "machine.h"
#include <linux/string.h>
static void __maps__insert(struct maps *maps, struct map *map);
const char *map_type__name[MAP__NR_TYPES] = {
[MAP__FUNCTION] = "Functions",
[MAP__VARIABLE] = "Variables",
};
static inline int is_anon_memory(const char *filename)
{
return !strcmp(filename, "//anon") ||
!strcmp(filename, "/dev/zero (deleted)") ||
!strcmp(filename, "/anon_hugepage (deleted)");
}
static inline int is_no_dso_memory(const char *filename)
{
return !strncmp(filename, "[stack", 6) ||
!strncmp(filename, "/SYSV",5) ||
!strcmp(filename, "[heap]");
}
static inline int is_android_lib(const char *filename)
{
return !strncmp(filename, "/data/app-lib", 13) ||
!strncmp(filename, "/system/lib", 11);
}
static inline bool replace_android_lib(const char *filename, char *newfilename)
{
const char *libname;
char *app_abi;
size_t app_abi_length, new_length;
size_t lib_length = 0;
libname = strrchr(filename, '/');
if (libname)
lib_length = strlen(libname);
app_abi = getenv("APP_ABI");
if (!app_abi)
return false;
app_abi_length = strlen(app_abi);
if (!strncmp(filename, "/data/app-lib", 13)) {
char *apk_path;
if (!app_abi_length)
return false;
new_length = 7 + app_abi_length + lib_length;
apk_path = getenv("APK_PATH");
if (apk_path) {
new_length += strlen(apk_path) + 1;
if (new_length > PATH_MAX)
return false;
snprintf(newfilename, new_length,
"%s/libs/%s/%s", apk_path, app_abi, libname);
} else {
if (new_length > PATH_MAX)
return false;
snprintf(newfilename, new_length,
"libs/%s/%s", app_abi, libname);
}
return true;
}
if (!strncmp(filename, "/system/lib/", 11)) {
char *ndk, *app;
const char *arch;
size_t ndk_length;
size_t app_length;
ndk = getenv("NDK_ROOT");
app = getenv("APP_PLATFORM");
if (!(ndk && app))
return false;
ndk_length = strlen(ndk);
app_length = strlen(app);
if (!(ndk_length && app_length && app_abi_length))
return false;
arch = !strncmp(app_abi, "arm", 3) ? "arm" :
!strncmp(app_abi, "mips", 4) ? "mips" :
!strncmp(app_abi, "x86", 3) ? "x86" : NULL;
if (!arch)
return false;
new_length = 27 + ndk_length +
app_length + lib_length
+ strlen(arch);
if (new_length > PATH_MAX)
return false;
snprintf(newfilename, new_length,
"%s/platforms/%s/arch-%s/usr/lib/%s",
ndk, app, arch, libname);
return true;
}
return false;
}
void map__init(struct map *map, enum map_type type,
u64 start, u64 end, u64 pgoff, struct dso *dso)
{
map->type = type;
map->start = start;
map->end = end;
map->pgoff = pgoff;
map->reloc = 0;
map->dso = dso__get(dso);
map->map_ip = map__map_ip;
map->unmap_ip = map__unmap_ip;
RB_CLEAR_NODE(&map->rb_node);
map->groups = NULL;
map->erange_warned = false;
atomic_set(&map->refcnt, 1);
}
struct map *map__new(struct machine *machine, u64 start, u64 len,
u64 pgoff, u32 pid, u32 d_maj, u32 d_min, u64 ino,
u64 ino_gen, u32 prot, u32 flags, char *filename,
enum map_type type, struct thread *thread)
{
struct map *map = malloc(sizeof(*map));
if (map != NULL) {
char newfilename[PATH_MAX];
struct dso *dso;
int anon, no_dso, vdso, android;
android = is_android_lib(filename);
anon = is_anon_memory(filename);
vdso = is_vdso_map(filename);
no_dso = is_no_dso_memory(filename);
map->maj = d_maj;
map->min = d_min;
map->ino = ino;
map->ino_generation = ino_gen;
map->prot = prot;
map->flags = flags;
if ((anon || no_dso) && type == MAP__FUNCTION) {
snprintf(newfilename, sizeof(newfilename), "/tmp/perf-%d.map", pid);
filename = newfilename;
}
if (android) {
if (replace_android_lib(filename, newfilename))
filename = newfilename;
}
if (vdso) {
pgoff = 0;
dso = machine__findnew_vdso(machine, thread);
} else
dso = machine__findnew_dso(machine, filename);
if (dso == NULL)
goto out_delete;
map__init(map, type, start, start + len, pgoff, dso);
if (anon || no_dso) {
map->map_ip = map->unmap_ip = identity__map_ip;
/*
* Set memory without DSO as loaded. All map__find_*
* functions still return NULL, and we avoid the
* unnecessary map__load warning.
*/
if (type != MAP__FUNCTION)
dso__set_loaded(dso, map->type);
}
dso__put(dso);
}
return map;
out_delete:
free(map);
return NULL;
}
/*
* 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.
*/
struct map *map__new2(u64 start, struct dso *dso, enum map_type type)
{
struct map *map = calloc(1, (sizeof(*map) +
(dso->kernel ? sizeof(struct kmap) : 0)));
if (map != NULL) {
/*
* ->end will be filled after we load all the symbols
*/
map__init(map, type, start, 0, 0, dso);
}
return map;
}
/*
* Use this and __map__is_kmodule() for map instances that are in
* machine->kmaps, and thus have map->groups->machine all properly set, to
* disambiguate between the kernel and modules.
*
* When the need arises, introduce map__is_{kernel,kmodule)() that
* checks (map->groups != NULL && map->groups->machine != NULL &&
* map->dso->kernel) before calling __map__is_{kernel,kmodule}())
*/
bool __map__is_kernel(const struct map *map)
{
return __machine__kernel_map(map->groups->machine, map->type) == map;
}
static void map__exit(struct map *map)
{
BUG_ON(!RB_EMPTY_NODE(&map->rb_node));
dso__zput(map->dso);
}
void map__delete(struct map *map)
{
map__exit(map);
free(map);
}
void map__put(struct map *map)
{
if (map && atomic_dec_and_test(&map->refcnt))
map__delete(map);
}
void map__fixup_start(struct map *map)
{
struct rb_root *symbols = &map->dso->symbols[map->type];
struct rb_node *nd = rb_first(symbols);
if (nd != NULL) {
struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
map->start = sym->start;
}
}
void map__fixup_end(struct map *map)
{
struct rb_root *symbols = &map->dso->symbols[map->type];
struct rb_node *nd = rb_last(symbols);
if (nd != NULL) {
struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
map->end = sym->end;
}
}
#define DSO__DELETED "(deleted)"
int map__load(struct map *map, symbol_filter_t filter)
{
const char *name = map->dso->long_name;
int nr;
if (dso__loaded(map->dso, map->type))
return 0;
nr = dso__load(map->dso, map, filter);
if (nr < 0) {
if (map->dso->has_build_id) {
char sbuild_id[BUILD_ID_SIZE * 2 + 1];
build_id__sprintf(map->dso->build_id,
sizeof(map->dso->build_id),
sbuild_id);
pr_warning("%s with build id %s not found",
name, sbuild_id);
} else
pr_warning("Failed to open %s", name);
pr_warning(", continuing without symbols\n");
return -1;
} else if (nr == 0) {
#ifdef HAVE_LIBELF_SUPPORT
const size_t len = strlen(name);
const size_t real_len = len - sizeof(DSO__DELETED);
if (len > sizeof(DSO__DELETED) &&
strcmp(name + real_len + 1, DSO__DELETED) == 0) {
pr_warning("%.*s was updated (is prelink enabled?). "
"Restart the long running apps that use it!\n",
(int)real_len, name);
} else {
pr_warning("no symbols found in %s, maybe install "
"a debug package?\n", name);
}
#endif
return -1;
}
return 0;
}
int __weak arch__compare_symbol_names(const char *namea, const char *nameb)
{
return strcmp(namea, nameb);
}
struct symbol *map__find_symbol(struct map *map, u64 addr,
symbol_filter_t filter)
{
if (map__load(map, filter) < 0)
return NULL;
return dso__find_symbol(map->dso, map->type, addr);
}
struct symbol *map__find_symbol_by_name(struct map *map, const char *name,
symbol_filter_t filter)
{
if (map__load(map, filter) < 0)
return NULL;
if (!dso__sorted_by_name(map->dso, map->type))
dso__sort_by_name(map->dso, map->type);
return dso__find_symbol_by_name(map->dso, map->type, name);
}
struct map *map__clone(struct map *from)
{
struct map *map = memdup(from, sizeof(*map));
if (map != NULL) {
atomic_set(&map->refcnt, 1);
RB_CLEAR_NODE(&map->rb_node);
dso__get(map->dso);
map->groups = NULL;
}
return map;
}
int map__overlap(struct map *l, struct map *r)
{
if (l->start > r->start) {
struct map *t = l;
l = r;
r = t;
}
if (l->end > r->start)
return 1;
return 0;
}
size_t map__fprintf(struct map *map, FILE *fp)
{
return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %" PRIx64 " %s\n",
map->start, map->end, map->pgoff, map->dso->name);
}
size_t map__fprintf_dsoname(struct map *map, FILE *fp)
{
const char *dsoname = "[unknown]";
if (map && map->dso && (map->dso->name || map->dso->long_name)) {
if (symbol_conf.show_kernel_path && map->dso->long_name)
dsoname = map->dso->long_name;
else if (map->dso->name)
dsoname = map->dso->name;
}
return fprintf(fp, "%s", dsoname);
}
int map__fprintf_srcline(struct map *map, u64 addr, const char *prefix,
FILE *fp)
{
char *srcline;
int ret = 0;
if (map && map->dso) {
srcline = get_srcline(map->dso,
map__rip_2objdump(map, addr), NULL, true);
if (srcline != SRCLINE_UNKNOWN)
ret = fprintf(fp, "%s%s", prefix, srcline);
free_srcline(srcline);
}
return ret;
}
/**
* map__rip_2objdump - convert symbol start address to objdump address.
* @map: memory map
* @rip: symbol start address
*
* objdump wants/reports absolute IPs for ET_EXEC, and RIPs for ET_DYN.
* map->dso->adjust_symbols==1 for ET_EXEC-like cases except ET_REL which is
* relative to section start.
*
* Return: Address suitable for passing to "objdump --start-address="
*/
u64 map__rip_2objdump(struct map *map, u64 rip)
{
if (!map->dso->adjust_symbols)
return rip;
if (map->dso->rel)
return rip - map->pgoff;
return map->unmap_ip(map, rip) - map->reloc;
}
/**
* map__objdump_2mem - convert objdump address to a memory address.
* @map: memory map
* @ip: objdump address
*
* Closely related to map__rip_2objdump(), this function takes an address from
* objdump and converts it to a memory address. Note this assumes that @map
* contains the address. To be sure the result is valid, check it forwards
* e.g. map__rip_2objdump(map->map_ip(map, map__objdump_2mem(map, ip))) == ip
*
* Return: Memory address.
*/
u64 map__objdump_2mem(struct map *map, u64 ip)
{
if (!map->dso->adjust_symbols)
return map->unmap_ip(map, ip);
if (map->dso->rel)
return map->unmap_ip(map, ip + map->pgoff);
return ip + map->reloc;
}
static void maps__init(struct maps *maps)
{
maps->entries = RB_ROOT;
pthread_rwlock_init(&maps->lock, NULL);
}
void map_groups__init(struct map_groups *mg, struct machine *machine)
{
int i;
for (i = 0; i < MAP__NR_TYPES; ++i) {
maps__init(&mg->maps[i]);
}
mg->machine = machine;
atomic_set(&mg->refcnt, 1);
}
static void __maps__purge(struct maps *maps)
{
struct rb_root *root = &maps->entries;
struct rb_node *next = rb_first(root);
while (next) {
struct map *pos = rb_entry(next, struct map, rb_node);
next = rb_next(&pos->rb_node);
rb_erase_init(&pos->rb_node, root);
map__put(pos);
}
}
static void maps__exit(struct maps *maps)
{
pthread_rwlock_wrlock(&maps->lock);
__maps__purge(maps);
pthread_rwlock_unlock(&maps->lock);
}
void map_groups__exit(struct map_groups *mg)
{
int i;
for (i = 0; i < MAP__NR_TYPES; ++i)
maps__exit(&mg->maps[i]);
}
bool map_groups__empty(struct map_groups *mg)
{
int i;
for (i = 0; i < MAP__NR_TYPES; ++i) {
if (maps__first(&mg->maps[i]))
return false;
}
return true;
}
struct map_groups *map_groups__new(struct machine *machine)
{
struct map_groups *mg = malloc(sizeof(*mg));
if (mg != NULL)
map_groups__init(mg, machine);
return mg;
}
void map_groups__delete(struct map_groups *mg)
{
map_groups__exit(mg);
free(mg);
}
void map_groups__put(struct map_groups *mg)
{
if (mg && atomic_dec_and_test(&mg->refcnt))
map_groups__delete(mg);
}
struct symbol *map_groups__find_symbol(struct map_groups *mg,
enum map_type type, u64 addr,
struct map **mapp,
symbol_filter_t filter)
{
struct map *map = map_groups__find(mg, type, addr);
/* Ensure map is loaded before using map->map_ip */
if (map != NULL && map__load(map, filter) >= 0) {
if (mapp != NULL)
*mapp = map;
return map__find_symbol(map, map->map_ip(map, addr), filter);
}
return NULL;
}
struct symbol *maps__find_symbol_by_name(struct maps *maps, const char *name,
struct map **mapp, symbol_filter_t filter)
{
struct symbol *sym;
struct rb_node *nd;
pthread_rwlock_rdlock(&maps->lock);
for (nd = rb_first(&maps->entries); nd; nd = rb_next(nd)) {
struct map *pos = rb_entry(nd, struct map, rb_node);
sym = map__find_symbol_by_name(pos, name, filter);
if (sym == NULL)
continue;
if (mapp != NULL)
*mapp = pos;
goto out;
}
sym = NULL;
out:
pthread_rwlock_unlock(&maps->lock);
return sym;
}
struct symbol *map_groups__find_symbol_by_name(struct map_groups *mg,
enum map_type type,
const char *name,
struct map **mapp,
symbol_filter_t filter)
{
struct symbol *sym = maps__find_symbol_by_name(&mg->maps[type], name, mapp, filter);
return sym;
}
int map_groups__find_ams(struct addr_map_symbol *ams, symbol_filter_t filter)
{
if (ams->addr < ams->map->start || ams->addr >= ams->map->end) {
if (ams->map->groups == NULL)
return -1;
ams->map = map_groups__find(ams->map->groups, ams->map->type,
ams->addr);
if (ams->map == NULL)
return -1;
}
ams->al_addr = ams->map->map_ip(ams->map, ams->addr);
ams->sym = map__find_symbol(ams->map, ams->al_addr, filter);
return ams->sym ? 0 : -1;
}
static size_t maps__fprintf(struct maps *maps, FILE *fp)
{
size_t printed = 0;
struct rb_node *nd;
pthread_rwlock_rdlock(&maps->lock);
for (nd = rb_first(&maps->entries); nd; nd = rb_next(nd)) {
struct map *pos = rb_entry(nd, struct map, rb_node);
printed += fprintf(fp, "Map:");
printed += map__fprintf(pos, fp);
if (verbose > 2) {
printed += dso__fprintf(pos->dso, pos->type, fp);
printed += fprintf(fp, "--\n");
}
}
pthread_rwlock_unlock(&maps->lock);
return printed;
}
size_t __map_groups__fprintf_maps(struct map_groups *mg, enum map_type type,
FILE *fp)
{
size_t printed = fprintf(fp, "%s:\n", map_type__name[type]);
return printed += maps__fprintf(&mg->maps[type], fp);
}
size_t map_groups__fprintf(struct map_groups *mg, FILE *fp)
{
size_t printed = 0, i;
for (i = 0; i < MAP__NR_TYPES; ++i)
printed += __map_groups__fprintf_maps(mg, i, fp);
return printed;
}
static void __map_groups__insert(struct map_groups *mg, struct map *map)
{
__maps__insert(&mg->maps[map->type], map);
map->groups = mg;
}
static int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
{
struct rb_root *root;
struct rb_node *next;
int err = 0;
pthread_rwlock_wrlock(&maps->lock);
root = &maps->entries;
next = rb_first(root);
while (next) {
struct map *pos = rb_entry(next, struct map, rb_node);
next = rb_next(&pos->rb_node);
if (!map__overlap(pos, map))
continue;
if (verbose >= 2) {
fputs("overlapping maps:\n", fp);
map__fprintf(map, fp);
map__fprintf(pos, fp);
}
rb_erase_init(&pos->rb_node, root);
/*
* Now check if we need to create new maps for areas not
* overlapped by the new map:
*/
if (map->start > pos->start) {
struct map *before = map__clone(pos);
if (before == NULL) {
err = -ENOMEM;
goto put_map;
}
before->end = map->start;
__map_groups__insert(pos->groups, before);
if (verbose >= 2)
map__fprintf(before, fp);
}
if (map->end < pos->end) {
struct map *after = map__clone(pos);
if (after == NULL) {
err = -ENOMEM;
goto put_map;
}
after->start = map->end;
__map_groups__insert(pos->groups, after);
if (verbose >= 2)
map__fprintf(after, fp);
}
put_map:
map__put(pos);
if (err)
goto out;
}
err = 0;
out:
pthread_rwlock_unlock(&maps->lock);
return err;
}
int map_groups__fixup_overlappings(struct map_groups *mg, struct map *map,
FILE *fp)
{
return maps__fixup_overlappings(&mg->maps[map->type], map, fp);
}
/*
* XXX This should not really _copy_ te maps, but refcount them.
*/
int map_groups__clone(struct map_groups *mg,
struct map_groups *parent, enum map_type type)
{
int err = -ENOMEM;
struct map *map;
struct maps *maps = &parent->maps[type];
pthread_rwlock_rdlock(&maps->lock);
for (map = maps__first(maps); map; map = map__next(map)) {
struct map *new = map__clone(map);
if (new == NULL)
goto out_unlock;
map_groups__insert(mg, new);
}
err = 0;
out_unlock:
pthread_rwlock_unlock(&maps->lock);
return err;
}
static void __maps__insert(struct maps *maps, struct map *map)
{
struct rb_node **p = &maps->entries.rb_node;
struct rb_node *parent = NULL;
const u64 ip = map->start;
struct map *m;
while (*p != NULL) {
parent = *p;
m = rb_entry(parent, struct map, rb_node);
if (ip < m->start)
p = &(*p)->rb_left;
else
p = &(*p)->rb_right;
}
rb_link_node(&map->rb_node, parent, p);
rb_insert_color(&map->rb_node, &maps->entries);
map__get(map);
}
void maps__insert(struct maps *maps, struct map *map)
{
pthread_rwlock_wrlock(&maps->lock);
__maps__insert(maps, map);
pthread_rwlock_unlock(&maps->lock);
}
static void __maps__remove(struct maps *maps, struct map *map)
{
rb_erase_init(&map->rb_node, &maps->entries);
map__put(map);
}
void maps__remove(struct maps *maps, struct map *map)
{
pthread_rwlock_wrlock(&maps->lock);
__maps__remove(maps, map);
pthread_rwlock_unlock(&maps->lock);
}
struct map *maps__find(struct maps *maps, u64 ip)
{
struct rb_node **p, *parent = NULL;
struct map *m;
pthread_rwlock_rdlock(&maps->lock);
p = &maps->entries.rb_node;
while (*p != NULL) {
parent = *p;
m = rb_entry(parent, struct map, rb_node);
if (ip < m->start)
p = &(*p)->rb_left;
else if (ip >= m->end)
p = &(*p)->rb_right;
else
goto out;
}
m = NULL;
out:
pthread_rwlock_unlock(&maps->lock);
return m;
}
struct map *maps__first(struct maps *maps)
{
struct rb_node *first = rb_first(&maps->entries);
if (first)
return rb_entry(first, struct map, rb_node);
return NULL;
}
struct map *map__next(struct map *map)
{
struct rb_node *next = rb_next(&map->rb_node);
if (next)
return rb_entry(next, struct map, rb_node);
return NULL;
}
struct kmap *map__kmap(struct map *map)
{
if (!map->dso || !map->dso->kernel) {
pr_err("Internal error: map__kmap with a non-kernel map\n");
return NULL;
}
return (struct kmap *)(map + 1);
}
struct map_groups *map__kmaps(struct map *map)
{
struct kmap *kmap = map__kmap(map);
if (!kmap || !kmap->kmaps) {
pr_err("Internal error: map__kmaps with a non-kernel map\n");
return NULL;
}
return kmap->kmaps;
}