// SPDX-License-Identifier: GPL-2.0
#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <linux/kernel.h>
#include <linux/zalloc.h>
#include "dso.h"
#include "session.h"
#include "thread.h"
#include "thread-stack.h"
#include "debug.h"
#include "namespaces.h"
#include "comm.h"
#include "map.h"
#include "symbol.h"
#include "unwind.h"
#include "callchain.h"
#include <api/fs/fs.h>
int thread__init_maps(struct thread *thread, struct machine *machine)
{
pid_t pid = thread__pid(thread);
if (pid == thread__tid(thread) || pid == -1) {
thread__set_maps(thread, maps__new(machine));
} else {
struct thread *leader = machine__findnew_thread(machine, pid, pid);
if (leader) {
thread__set_maps(thread, maps__get(thread__maps(leader)));
thread__put(leader);
}
}
return thread__maps(thread) ? 0 : -1;
}
struct thread *thread__new(pid_t pid, pid_t tid)
{
RC_STRUCT(thread) *_thread = zalloc(sizeof(*_thread));
struct thread *thread;
if (ADD_RC_CHK(thread, _thread) != NULL) {
struct comm *comm;
char comm_str[32];
thread__set_pid(thread, pid);
thread__set_tid(thread, tid);
thread__set_ppid(thread, -1);
thread__set_cpu(thread, -1);
thread__set_guest_cpu(thread, -1);
thread__set_lbr_stitch_enable(thread, false);
INIT_LIST_HEAD(thread__namespaces_list(thread));
INIT_LIST_HEAD(thread__comm_list(thread));
init_rwsem(thread__namespaces_lock(thread));
init_rwsem(thread__comm_lock(thread));
snprintf(comm_str, sizeof(comm_str), ":%d", tid);
comm = comm__new(comm_str, 0, false);
if (!comm)
goto err_thread;
list_add(&comm->list, thread__comm_list(thread));
refcount_set(thread__refcnt(thread), 1);
/* Thread holds first ref to nsdata. */
RC_CHK_ACCESS(thread)->nsinfo = nsinfo__new(pid);
srccode_state_init(thread__srccode_state(thread));
}
return thread;
err_thread:
thread__delete(thread);
return NULL;
}
static void (*thread__priv_destructor)(void *priv);
void thread__set_priv_destructor(void (*destructor)(void *priv))
{
assert(thread__priv_destructor == NULL);
thread__priv_destructor = destructor;
}
void thread__delete(struct thread *thread)
{
struct namespaces *namespaces, *tmp_namespaces;
struct comm *comm, *tmp_comm;
thread_stack__free(thread);
if (thread__maps(thread)) {
maps__put(thread__maps(thread));
thread__set_maps(thread, NULL);
}
down_write(thread__namespaces_lock(thread));
list_for_each_entry_safe(namespaces, tmp_namespaces,
thread__namespaces_list(thread), list) {
list_del_init(&namespaces->list);
namespaces__free(namespaces);
}
up_write(thread__namespaces_lock(thread));
down_write(thread__comm_lock(thread));
list_for_each_entry_safe(comm, tmp_comm, thread__comm_list(thread), list) {
list_del_init(&comm->list);
comm__free(comm);
}
up_write(thread__comm_lock(thread));
nsinfo__zput(RC_CHK_ACCESS(thread)->nsinfo);
srccode_state_free(thread__srccode_state(thread));
exit_rwsem(thread__namespaces_lock(thread));
exit_rwsem(thread__comm_lock(thread));
thread__free_stitch_list(thread);
if (thread__priv_destructor)
thread__priv_destructor(thread__priv(thread));
RC_CHK_FREE(thread);
}
struct thread *thread__get(struct thread *thread)
{
struct thread *result;
if (RC_CHK_GET(result, thread))
refcount_inc(thread__refcnt(thread));
return result;
}
void thread__put(struct thread *thread)
{
if (thread && refcount_dec_and_test(thread__refcnt(thread)))
thread__delete(thread);
else
RC_CHK_PUT(thread);
}
static struct namespaces *__thread__namespaces(struct thread *thread)
{
if (list_empty(thread__namespaces_list(thread)))
return NULL;
return list_first_entry(thread__namespaces_list(thread), struct namespaces, list);
}
struct namespaces *thread__namespaces(struct thread *thread)
{
struct namespaces *ns;
down_read(thread__namespaces_lock(thread));
ns = __thread__namespaces(thread);
up_read(thread__namespaces_lock(thread));
return ns;
}
static int __thread__set_namespaces(struct thread *thread, u64 timestamp,
struct perf_record_namespaces *event)
{
struct namespaces *new, *curr = __thread__namespaces(thread);
new = namespaces__new(event);
if (!new)
return -ENOMEM;
list_add(&new->list, thread__namespaces_list(thread));
if (timestamp && curr) {
/*
* setns syscall must have changed few or all the namespaces
* of this thread. Update end time for the namespaces
* previously used.
*/
curr = list_next_entry(new, list);
curr->end_time = timestamp;
}
return 0;
}
int thread__set_namespaces(struct thread *thread, u64 timestamp,
struct perf_record_namespaces *event)
{
int ret;
down_write(thread__namespaces_lock(thread));
ret = __thread__set_namespaces(thread, timestamp, event);
up_write(thread__namespaces_lock(thread));
return ret;
}
struct comm *thread__comm(struct thread *thread)
{
if (list_empty(thread__comm_list(thread)))
return NULL;
return list_first_entry(thread__comm_list(thread), struct comm, list);
}
struct comm *thread__exec_comm(struct thread *thread)
{
struct comm *comm, *last = NULL, *second_last = NULL;
list_for_each_entry(comm, thread__comm_list(thread), list) {
if (comm->exec)
return comm;
second_last = last;
last = comm;
}
/*
* 'last' with no start time might be the parent's comm of a synthesized
* thread (created by processing a synthesized fork event). For a main
* thread, that is very probably wrong. Prefer a later comm to avoid
* that case.
*/
if (second_last && !last->start && thread__pid(thread) == thread__tid(thread))
return second_last;
return last;
}
static int ____thread__set_comm(struct thread *thread, const char *str,
u64 timestamp, bool exec)
{
struct comm *new, *curr = thread__comm(thread);
/* Override the default :tid entry */
if (!thread__comm_set(thread)) {
int err = comm__override(curr, str, timestamp, exec);
if (err)
return err;
} else {
new = comm__new(str, timestamp, exec);
if (!new)
return -ENOMEM;
list_add(&new->list, thread__comm_list(thread));
if (exec)
unwind__flush_access(thread__maps(thread));
}
thread__set_comm_set(thread, true);
return 0;
}
int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp,
bool exec)
{
int ret;
down_write(thread__comm_lock(thread));
ret = ____thread__set_comm(thread, str, timestamp, exec);
up_write(thread__comm_lock(thread));
return ret;
}
int thread__set_comm_from_proc(struct thread *thread)
{
char path[64];
char *comm = NULL;
size_t sz;
int err = -1;
if (!(snprintf(path, sizeof(path), "%d/task/%d/comm",
thread__pid(thread), thread__tid(thread)) >= (int)sizeof(path)) &&
procfs__read_str(path, &comm, &sz) == 0) {
comm[sz - 1] = '\0';
err = thread__set_comm(thread, comm, 0);
}
return err;
}
static const char *__thread__comm_str(struct thread *thread)
{
const struct comm *comm = thread__comm(thread);
if (!comm)
return NULL;
return comm__str(comm);
}
const char *thread__comm_str(struct thread *thread)
{
const char *str;
down_read(thread__comm_lock(thread));
str = __thread__comm_str(thread);
up_read(thread__comm_lock(thread));
return str;
}
static int __thread__comm_len(struct thread *thread, const char *comm)
{
if (!comm)
return 0;
thread__set_comm_len(thread, strlen(comm));
return thread__var_comm_len(thread);
}
/* CHECKME: it should probably better return the max comm len from its comm list */
int thread__comm_len(struct thread *thread)
{
int comm_len = thread__var_comm_len(thread);
if (!comm_len) {
const char *comm;
down_read(thread__comm_lock(thread));
comm = __thread__comm_str(thread);
comm_len = __thread__comm_len(thread, comm);
up_read(thread__comm_lock(thread));
}
return comm_len;
}
size_t thread__fprintf(struct thread *thread, FILE *fp)
{
return fprintf(fp, "Thread %d %s\n", thread__tid(thread), thread__comm_str(thread)) +
maps__fprintf(thread__maps(thread), fp);
}
int thread__insert_map(struct thread *thread, struct map *map)
{
int ret;
ret = unwind__prepare_access(thread__maps(thread), map, NULL);
if (ret)
return ret;
return maps__fixup_overlap_and_insert(thread__maps(thread), map);
}
struct thread__prepare_access_maps_cb_args {
int err;
struct maps *maps;
};
static int thread__prepare_access_maps_cb(struct map *map, void *data)
{
bool initialized = false;
struct thread__prepare_access_maps_cb_args *args = data;
args->err = unwind__prepare_access(args->maps, map, &initialized);
return (args->err || initialized) ? 1 : 0;
}
static int thread__prepare_access(struct thread *thread)
{
struct thread__prepare_access_maps_cb_args args = {
.err = 0,
};
if (dwarf_callchain_users) {
args.maps = thread__maps(thread);
maps__for_each_map(thread__maps(thread), thread__prepare_access_maps_cb, &args);
}
return args.err;
}
static int thread__clone_maps(struct thread *thread, struct thread *parent, bool do_maps_clone)
{
/* This is new thread, we share map groups for process. */
if (thread__pid(thread) == thread__pid(parent))
return thread__prepare_access(thread);
if (maps__equal(thread__maps(thread), thread__maps(parent))) {
pr_debug("broken map groups on thread %d/%d parent %d/%d\n",
thread__pid(thread), thread__tid(thread),
thread__pid(parent), thread__tid(parent));
return 0;
}
/* But this one is new process, copy maps. */
return do_maps_clone ? maps__copy_from(thread__maps(thread), thread__maps(parent)) : 0;
}
int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp, bool do_maps_clone)
{
if (thread__comm_set(parent)) {
const char *comm = thread__comm_str(parent);
int err;
if (!comm)
return -ENOMEM;
err = thread__set_comm(thread, comm, timestamp);
if (err)
return err;
}
thread__set_ppid(thread, thread__tid(parent));
return thread__clone_maps(thread, parent, do_maps_clone);
}
void thread__find_cpumode_addr_location(struct thread *thread, u64 addr,
struct addr_location *al)
{
size_t i;
const u8 cpumodes[] = {
PERF_RECORD_MISC_USER,
PERF_RECORD_MISC_KERNEL,
PERF_RECORD_MISC_GUEST_USER,
PERF_RECORD_MISC_GUEST_KERNEL
};
for (i = 0; i < ARRAY_SIZE(cpumodes); i++) {
thread__find_symbol(thread, cpumodes[i], addr, al);
if (al->map)
break;
}
}
struct thread *thread__main_thread(struct machine *machine, struct thread *thread)
{
if (thread__pid(thread) == thread__tid(thread))
return thread__get(thread);
if (thread__pid(thread) == -1)
return NULL;
return machine__find_thread(machine, thread__pid(thread), thread__pid(thread));
}
int thread__memcpy(struct thread *thread, struct machine *machine,
void *buf, u64 ip, int len, bool *is64bit)
{
u8 cpumode = PERF_RECORD_MISC_USER;
struct addr_location al;
struct dso *dso;
long offset;
if (machine__kernel_ip(machine, ip))
cpumode = PERF_RECORD_MISC_KERNEL;
addr_location__init(&al);
if (!thread__find_map(thread, cpumode, ip, &al)) {
addr_location__exit(&al);
return -1;
}
dso = map__dso(al.map);
if (!dso || dso__data(dso)->status == DSO_DATA_STATUS_ERROR || map__load(al.map) < 0) {
addr_location__exit(&al);
return -1;
}
offset = map__map_ip(al.map, ip);
if (is64bit)
*is64bit = dso__is_64_bit(dso);
addr_location__exit(&al);
return dso__data_read_offset(dso, machine, offset, buf, len);
}
void thread__free_stitch_list(struct thread *thread)
{
struct lbr_stitch *lbr_stitch = thread__lbr_stitch(thread);
struct stitch_list *pos, *tmp;
if (!lbr_stitch)
return;
list_for_each_entry_safe(pos, tmp, &lbr_stitch->lists, node) {
map_symbol__exit(&pos->cursor.ms);
list_del_init(&pos->node);
free(pos);
}
list_for_each_entry_safe(pos, tmp, &lbr_stitch->free_lists, node) {
list_del_init(&pos->node);
free(pos);
}
for (unsigned int i = 0 ; i < lbr_stitch->prev_lbr_cursor_size; i++)
map_symbol__exit(&lbr_stitch->prev_lbr_cursor[i].ms);
zfree(&lbr_stitch->prev_lbr_cursor);
free(thread__lbr_stitch(thread));
thread__set_lbr_stitch(thread, NULL);
}
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