blob: bff425e1232cdcb99f362e1b7d5971e5d1121a23 [file] [log] [blame]
/*
* build-id.c
*
* build-id support
*
* Copyright (C) 2009, 2010 Red Hat Inc.
* Copyright (C) 2009, 2010 Arnaldo Carvalho de Melo <acme@redhat.com>
*/
#include "util.h"
#include <stdio.h>
#include "build-id.h"
#include "event.h"
#include "symbol.h"
#include <linux/kernel.h>
#include "debug.h"
#include "session.h"
#include "tool.h"
#include "header.h"
#include "vdso.h"
static bool no_buildid_cache;
int build_id__mark_dso_hit(struct perf_tool *tool __maybe_unused,
union perf_event *event,
struct perf_sample *sample,
struct perf_evsel *evsel __maybe_unused,
struct machine *machine)
{
struct addr_location al;
struct thread *thread = machine__findnew_thread(machine, sample->pid,
sample->tid);
if (thread == NULL) {
pr_err("problem processing %d event, skipping it.\n",
event->header.type);
return -1;
}
thread__find_addr_map(thread, sample->cpumode, MAP__FUNCTION, sample->ip, &al);
if (al.map != NULL)
al.map->dso->hit = 1;
thread__put(thread);
return 0;
}
static int perf_event__exit_del_thread(struct perf_tool *tool __maybe_unused,
union perf_event *event,
struct perf_sample *sample
__maybe_unused,
struct machine *machine)
{
struct thread *thread = machine__findnew_thread(machine,
event->fork.pid,
event->fork.tid);
dump_printf("(%d:%d):(%d:%d)\n", event->fork.pid, event->fork.tid,
event->fork.ppid, event->fork.ptid);
if (thread) {
machine__remove_thread(machine, thread);
thread__put(thread);
}
return 0;
}
struct perf_tool build_id__mark_dso_hit_ops = {
.sample = build_id__mark_dso_hit,
.mmap = perf_event__process_mmap,
.mmap2 = perf_event__process_mmap2,
.fork = perf_event__process_fork,
.exit = perf_event__exit_del_thread,
.attr = perf_event__process_attr,
.build_id = perf_event__process_build_id,
.ordered_events = true,
};
int build_id__sprintf(const u8 *build_id, int len, char *bf)
{
char *bid = bf;
const u8 *raw = build_id;
int i;
for (i = 0; i < len; ++i) {
sprintf(bid, "%02x", *raw);
++raw;
bid += 2;
}
return (bid - bf) + 1;
}
int sysfs__sprintf_build_id(const char *root_dir, char *sbuild_id)
{
char notes[PATH_MAX];
u8 build_id[BUILD_ID_SIZE];
int ret;
if (!root_dir)
root_dir = "";
scnprintf(notes, sizeof(notes), "%s/sys/kernel/notes", root_dir);
ret = sysfs__read_build_id(notes, build_id, sizeof(build_id));
if (ret < 0)
return ret;
return build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
}
int filename__sprintf_build_id(const char *pathname, char *sbuild_id)
{
u8 build_id[BUILD_ID_SIZE];
int ret;
ret = filename__read_build_id(pathname, build_id, sizeof(build_id));
if (ret < 0)
return ret;
else if (ret != sizeof(build_id))
return -EINVAL;
return build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
}
/* asnprintf consolidates asprintf and snprintf */
static int asnprintf(char **strp, size_t size, const char *fmt, ...)
{
va_list ap;
int ret;
if (!strp)
return -EINVAL;
va_start(ap, fmt);
if (*strp)
ret = vsnprintf(*strp, size, fmt, ap);
else
ret = vasprintf(strp, fmt, ap);
va_end(ap);
return ret;
}
static char *build_id__filename(const char *sbuild_id, char *bf, size_t size)
{
char *tmp = bf;
int ret = asnprintf(&bf, size, "%s/.build-id/%.2s/%s", buildid_dir,
sbuild_id, sbuild_id + 2);
if (ret < 0 || (tmp && size < (unsigned int)ret))
return NULL;
return bf;
}
char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size)
{
char build_id_hex[SBUILD_ID_SIZE];
if (!dso->has_build_id)
return NULL;
build_id__sprintf(dso->build_id, sizeof(dso->build_id), build_id_hex);
return build_id__filename(build_id_hex, bf, size);
}
bool dso__build_id_is_kmod(const struct dso *dso, char *bf, size_t size)
{
char *id_name, *ch;
struct stat sb;
id_name = dso__build_id_filename(dso, bf, size);
if (!id_name)
goto err;
if (access(id_name, F_OK))
goto err;
if (lstat(id_name, &sb) == -1)
goto err;
if ((size_t)sb.st_size > size - 1)
goto err;
if (readlink(id_name, bf, size - 1) < 0)
goto err;
bf[sb.st_size] = '\0';
/*
* link should be:
* ../../lib/modules/4.4.0-rc4/kernel/net/ipv4/netfilter/nf_nat_ipv4.ko/a09fe3eb3147dafa4e3b31dbd6257e4d696bdc92
*/
ch = strrchr(bf, '/');
if (!ch)
goto err;
if (ch - 3 < bf)
goto err;
return strncmp(".ko", ch - 3, 3) == 0;
err:
/*
* If dso__build_id_filename work, get id_name again,
* because id_name points to bf and is broken.
*/
if (id_name)
id_name = dso__build_id_filename(dso, bf, size);
pr_err("Invalid build id: %s\n", id_name ? :
dso->long_name ? :
dso->short_name ? :
"[unknown]");
return false;
}
#define dsos__for_each_with_build_id(pos, head) \
list_for_each_entry(pos, head, node) \
if (!pos->has_build_id) \
continue; \
else
static int write_buildid(const char *name, size_t name_len, u8 *build_id,
pid_t pid, u16 misc, int fd)
{
int err;
struct build_id_event b;
size_t len;
len = name_len + 1;
len = PERF_ALIGN(len, NAME_ALIGN);
memset(&b, 0, sizeof(b));
memcpy(&b.build_id, build_id, BUILD_ID_SIZE);
b.pid = pid;
b.header.misc = misc;
b.header.size = sizeof(b) + len;
err = writen(fd, &b, sizeof(b));
if (err < 0)
return err;
return write_padded(fd, name, name_len + 1, len);
}
static int machine__write_buildid_table(struct machine *machine, int fd)
{
int err = 0;
char nm[PATH_MAX];
struct dso *pos;
u16 kmisc = PERF_RECORD_MISC_KERNEL,
umisc = PERF_RECORD_MISC_USER;
if (!machine__is_host(machine)) {
kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
umisc = PERF_RECORD_MISC_GUEST_USER;
}
dsos__for_each_with_build_id(pos, &machine->dsos.head) {
const char *name;
size_t name_len;
bool in_kernel = false;
if (!pos->hit)
continue;
if (dso__is_vdso(pos)) {
name = pos->short_name;
name_len = pos->short_name_len;
} else if (dso__is_kcore(pos)) {
machine__mmap_name(machine, nm, sizeof(nm));
name = nm;
name_len = strlen(nm);
} else {
name = pos->long_name;
name_len = pos->long_name_len;
}
in_kernel = pos->kernel ||
is_kernel_module(name,
PERF_RECORD_MISC_CPUMODE_UNKNOWN);
err = write_buildid(name, name_len, pos->build_id, machine->pid,
in_kernel ? kmisc : umisc, fd);
if (err)
break;
}
return err;
}
int perf_session__write_buildid_table(struct perf_session *session, int fd)
{
struct rb_node *nd;
int err = machine__write_buildid_table(&session->machines.host, fd);
if (err)
return err;
for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
struct machine *pos = rb_entry(nd, struct machine, rb_node);
err = machine__write_buildid_table(pos, fd);
if (err)
break;
}
return err;
}
static int __dsos__hit_all(struct list_head *head)
{
struct dso *pos;
list_for_each_entry(pos, head, node)
pos->hit = true;
return 0;
}
static int machine__hit_all_dsos(struct machine *machine)
{
return __dsos__hit_all(&machine->dsos.head);
}
int dsos__hit_all(struct perf_session *session)
{
struct rb_node *nd;
int err;
err = machine__hit_all_dsos(&session->machines.host);
if (err)
return err;
for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
struct machine *pos = rb_entry(nd, struct machine, rb_node);
err = machine__hit_all_dsos(pos);
if (err)
return err;
}
return 0;
}
void disable_buildid_cache(void)
{
no_buildid_cache = true;
}
static char *build_id_cache__dirname_from_path(const char *name,
bool is_kallsyms, bool is_vdso)
{
char *realname = (char *)name, *filename;
bool slash = is_kallsyms || is_vdso;
if (!slash) {
realname = realpath(name, NULL);
if (!realname)
return NULL;
}
if (asprintf(&filename, "%s%s%s", buildid_dir, slash ? "/" : "",
is_vdso ? DSO__NAME_VDSO : realname) < 0)
filename = NULL;
if (!slash)
free(realname);
return filename;
}
int build_id_cache__list_build_ids(const char *pathname,
struct strlist **result)
{
char *dir_name;
int ret = 0;
dir_name = build_id_cache__dirname_from_path(pathname, false, false);
if (!dir_name)
return -ENOMEM;
*result = lsdir(dir_name, lsdir_no_dot_filter);
if (!*result)
ret = -errno;
free(dir_name);
return ret;
}
int build_id_cache__add_s(const char *sbuild_id, const char *name,
bool is_kallsyms, bool is_vdso)
{
const size_t size = PATH_MAX;
char *realname = NULL, *filename = NULL, *dir_name = NULL,
*linkname = zalloc(size), *targetname, *tmp;
int err = -1;
if (!is_kallsyms) {
realname = realpath(name, NULL);
if (!realname)
goto out_free;
}
dir_name = build_id_cache__dirname_from_path(name, is_kallsyms, is_vdso);
if (!dir_name)
goto out_free;
if (mkdir_p(dir_name, 0755))
goto out_free;
if (asprintf(&filename, "%s/%s", dir_name, sbuild_id) < 0) {
filename = NULL;
goto out_free;
}
if (access(filename, F_OK)) {
if (is_kallsyms) {
if (copyfile("/proc/kallsyms", filename))
goto out_free;
} else if (link(realname, filename) && errno != EEXIST &&
copyfile(name, filename))
goto out_free;
}
if (!build_id__filename(sbuild_id, linkname, size))
goto out_free;
tmp = strrchr(linkname, '/');
*tmp = '\0';
if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
goto out_free;
*tmp = '/';
targetname = filename + strlen(buildid_dir) - 5;
memcpy(targetname, "../..", 5);
if (symlink(targetname, linkname) == 0)
err = 0;
out_free:
if (!is_kallsyms)
free(realname);
free(filename);
free(dir_name);
free(linkname);
return err;
}
static int build_id_cache__add_b(const u8 *build_id, size_t build_id_size,
const char *name, bool is_kallsyms,
bool is_vdso)
{
char sbuild_id[SBUILD_ID_SIZE];
build_id__sprintf(build_id, build_id_size, sbuild_id);
return build_id_cache__add_s(sbuild_id, name, is_kallsyms, is_vdso);
}
bool build_id_cache__cached(const char *sbuild_id)
{
bool ret = false;
char *filename = build_id__filename(sbuild_id, NULL, 0);
if (filename && !access(filename, F_OK))
ret = true;
free(filename);
return ret;
}
int build_id_cache__remove_s(const char *sbuild_id)
{
const size_t size = PATH_MAX;
char *filename = zalloc(size),
*linkname = zalloc(size), *tmp;
int err = -1;
if (filename == NULL || linkname == NULL)
goto out_free;
if (!build_id__filename(sbuild_id, linkname, size))
goto out_free;
if (access(linkname, F_OK))
goto out_free;
if (readlink(linkname, filename, size - 1) < 0)
goto out_free;
if (unlink(linkname))
goto out_free;
/*
* Since the link is relative, we must make it absolute:
*/
tmp = strrchr(linkname, '/') + 1;
snprintf(tmp, size - (tmp - linkname), "%s", filename);
if (unlink(linkname))
goto out_free;
err = 0;
out_free:
free(filename);
free(linkname);
return err;
}
static int dso__cache_build_id(struct dso *dso, struct machine *machine)
{
bool is_kallsyms = dso->kernel && dso->long_name[0] != '/';
bool is_vdso = dso__is_vdso(dso);
const char *name = dso->long_name;
char nm[PATH_MAX];
if (dso__is_kcore(dso)) {
is_kallsyms = true;
machine__mmap_name(machine, nm, sizeof(nm));
name = nm;
}
return build_id_cache__add_b(dso->build_id, sizeof(dso->build_id), name,
is_kallsyms, is_vdso);
}
static int __dsos__cache_build_ids(struct list_head *head,
struct machine *machine)
{
struct dso *pos;
int err = 0;
dsos__for_each_with_build_id(pos, head)
if (dso__cache_build_id(pos, machine))
err = -1;
return err;
}
static int machine__cache_build_ids(struct machine *machine)
{
return __dsos__cache_build_ids(&machine->dsos.head, machine);
}
int perf_session__cache_build_ids(struct perf_session *session)
{
struct rb_node *nd;
int ret;
if (no_buildid_cache)
return 0;
if (mkdir(buildid_dir, 0755) != 0 && errno != EEXIST)
return -1;
ret = machine__cache_build_ids(&session->machines.host);
for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
struct machine *pos = rb_entry(nd, struct machine, rb_node);
ret |= machine__cache_build_ids(pos);
}
return ret ? -1 : 0;
}
static bool machine__read_build_ids(struct machine *machine, bool with_hits)
{
return __dsos__read_build_ids(&machine->dsos.head, with_hits);
}
bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
{
struct rb_node *nd;
bool ret = machine__read_build_ids(&session->machines.host, with_hits);
for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
struct machine *pos = rb_entry(nd, struct machine, rb_node);
ret |= machine__read_build_ids(pos, with_hits);
}
return ret;
}