496 lines · c
1// SPDX-License-Identifier: GPL-2.02#include <errno.h>3#include <stdlib.h>4#include <stdio.h>5#include <string.h>6#include <linux/kernel.h>7#include <linux/zalloc.h>8#include "dso.h"9#include "session.h"10#include "thread.h"11#include "thread-stack.h"12#include "debug.h"13#include "namespaces.h"14#include "comm.h"15#include "map.h"16#include "symbol.h"17#include "unwind.h"18#include "callchain.h"19 20#include <api/fs/fs.h>21 22int thread__init_maps(struct thread *thread, struct machine *machine)23{24 pid_t pid = thread__pid(thread);25 26 if (pid == thread__tid(thread) || pid == -1) {27 thread__set_maps(thread, maps__new(machine));28 } else {29 struct thread *leader = machine__findnew_thread(machine, pid, pid);30 31 if (leader) {32 thread__set_maps(thread, maps__get(thread__maps(leader)));33 thread__put(leader);34 }35 }36 37 return thread__maps(thread) ? 0 : -1;38}39 40struct thread *thread__new(pid_t pid, pid_t tid)41{42 RC_STRUCT(thread) *_thread = zalloc(sizeof(*_thread));43 struct thread *thread;44 45 if (ADD_RC_CHK(thread, _thread) != NULL) {46 struct comm *comm;47 char comm_str[32];48 49 thread__set_pid(thread, pid);50 thread__set_tid(thread, tid);51 thread__set_ppid(thread, -1);52 thread__set_cpu(thread, -1);53 thread__set_guest_cpu(thread, -1);54 thread__set_lbr_stitch_enable(thread, false);55 INIT_LIST_HEAD(thread__namespaces_list(thread));56 INIT_LIST_HEAD(thread__comm_list(thread));57 init_rwsem(thread__namespaces_lock(thread));58 init_rwsem(thread__comm_lock(thread));59 60 snprintf(comm_str, sizeof(comm_str), ":%d", tid);61 comm = comm__new(comm_str, 0, false);62 if (!comm)63 goto err_thread;64 65 list_add(&comm->list, thread__comm_list(thread));66 refcount_set(thread__refcnt(thread), 1);67 /* Thread holds first ref to nsdata. */68 RC_CHK_ACCESS(thread)->nsinfo = nsinfo__new(pid);69 srccode_state_init(thread__srccode_state(thread));70 }71 72 return thread;73 74err_thread:75 thread__delete(thread);76 return NULL;77}78 79static void (*thread__priv_destructor)(void *priv);80 81void thread__set_priv_destructor(void (*destructor)(void *priv))82{83 assert(thread__priv_destructor == NULL);84 85 thread__priv_destructor = destructor;86}87 88void thread__delete(struct thread *thread)89{90 struct namespaces *namespaces, *tmp_namespaces;91 struct comm *comm, *tmp_comm;92 93 thread_stack__free(thread);94 95 if (thread__maps(thread)) {96 maps__put(thread__maps(thread));97 thread__set_maps(thread, NULL);98 }99 down_write(thread__namespaces_lock(thread));100 list_for_each_entry_safe(namespaces, tmp_namespaces,101 thread__namespaces_list(thread), list) {102 list_del_init(&namespaces->list);103 namespaces__free(namespaces);104 }105 up_write(thread__namespaces_lock(thread));106 107 down_write(thread__comm_lock(thread));108 list_for_each_entry_safe(comm, tmp_comm, thread__comm_list(thread), list) {109 list_del_init(&comm->list);110 comm__free(comm);111 }112 up_write(thread__comm_lock(thread));113 114 nsinfo__zput(RC_CHK_ACCESS(thread)->nsinfo);115 srccode_state_free(thread__srccode_state(thread));116 117 exit_rwsem(thread__namespaces_lock(thread));118 exit_rwsem(thread__comm_lock(thread));119 thread__free_stitch_list(thread);120 121 if (thread__priv_destructor)122 thread__priv_destructor(thread__priv(thread));123 124 RC_CHK_FREE(thread);125}126 127struct thread *thread__get(struct thread *thread)128{129 struct thread *result;130 131 if (RC_CHK_GET(result, thread))132 refcount_inc(thread__refcnt(thread));133 134 return result;135}136 137void thread__put(struct thread *thread)138{139 if (thread && refcount_dec_and_test(thread__refcnt(thread)))140 thread__delete(thread);141 else142 RC_CHK_PUT(thread);143}144 145static struct namespaces *__thread__namespaces(struct thread *thread)146{147 if (list_empty(thread__namespaces_list(thread)))148 return NULL;149 150 return list_first_entry(thread__namespaces_list(thread), struct namespaces, list);151}152 153struct namespaces *thread__namespaces(struct thread *thread)154{155 struct namespaces *ns;156 157 down_read(thread__namespaces_lock(thread));158 ns = __thread__namespaces(thread);159 up_read(thread__namespaces_lock(thread));160 161 return ns;162}163 164static int __thread__set_namespaces(struct thread *thread, u64 timestamp,165 struct perf_record_namespaces *event)166{167 struct namespaces *new, *curr = __thread__namespaces(thread);168 169 new = namespaces__new(event);170 if (!new)171 return -ENOMEM;172 173 list_add(&new->list, thread__namespaces_list(thread));174 175 if (timestamp && curr) {176 /*177 * setns syscall must have changed few or all the namespaces178 * of this thread. Update end time for the namespaces179 * previously used.180 */181 curr = list_next_entry(new, list);182 curr->end_time = timestamp;183 }184 185 return 0;186}187 188int thread__set_namespaces(struct thread *thread, u64 timestamp,189 struct perf_record_namespaces *event)190{191 int ret;192 193 down_write(thread__namespaces_lock(thread));194 ret = __thread__set_namespaces(thread, timestamp, event);195 up_write(thread__namespaces_lock(thread));196 return ret;197}198 199struct comm *thread__comm(struct thread *thread)200{201 if (list_empty(thread__comm_list(thread)))202 return NULL;203 204 return list_first_entry(thread__comm_list(thread), struct comm, list);205}206 207struct comm *thread__exec_comm(struct thread *thread)208{209 struct comm *comm, *last = NULL, *second_last = NULL;210 211 list_for_each_entry(comm, thread__comm_list(thread), list) {212 if (comm->exec)213 return comm;214 second_last = last;215 last = comm;216 }217 218 /*219 * 'last' with no start time might be the parent's comm of a synthesized220 * thread (created by processing a synthesized fork event). For a main221 * thread, that is very probably wrong. Prefer a later comm to avoid222 * that case.223 */224 if (second_last && !last->start && thread__pid(thread) == thread__tid(thread))225 return second_last;226 227 return last;228}229 230static int ____thread__set_comm(struct thread *thread, const char *str,231 u64 timestamp, bool exec)232{233 struct comm *new, *curr = thread__comm(thread);234 235 /* Override the default :tid entry */236 if (!thread__comm_set(thread)) {237 int err = comm__override(curr, str, timestamp, exec);238 if (err)239 return err;240 } else {241 new = comm__new(str, timestamp, exec);242 if (!new)243 return -ENOMEM;244 list_add(&new->list, thread__comm_list(thread));245 246 if (exec)247 unwind__flush_access(thread__maps(thread));248 }249 250 thread__set_comm_set(thread, true);251 252 return 0;253}254 255int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp,256 bool exec)257{258 int ret;259 260 down_write(thread__comm_lock(thread));261 ret = ____thread__set_comm(thread, str, timestamp, exec);262 up_write(thread__comm_lock(thread));263 return ret;264}265 266int thread__set_comm_from_proc(struct thread *thread)267{268 char path[64];269 char *comm = NULL;270 size_t sz;271 int err = -1;272 273 if (!(snprintf(path, sizeof(path), "%d/task/%d/comm",274 thread__pid(thread), thread__tid(thread)) >= (int)sizeof(path)) &&275 procfs__read_str(path, &comm, &sz) == 0) {276 comm[sz - 1] = '\0';277 err = thread__set_comm(thread, comm, 0);278 }279 280 return err;281}282 283static const char *__thread__comm_str(struct thread *thread)284{285 const struct comm *comm = thread__comm(thread);286 287 if (!comm)288 return NULL;289 290 return comm__str(comm);291}292 293const char *thread__comm_str(struct thread *thread)294{295 const char *str;296 297 down_read(thread__comm_lock(thread));298 str = __thread__comm_str(thread);299 up_read(thread__comm_lock(thread));300 301 return str;302}303 304static int __thread__comm_len(struct thread *thread, const char *comm)305{306 if (!comm)307 return 0;308 thread__set_comm_len(thread, strlen(comm));309 310 return thread__var_comm_len(thread);311}312 313/* CHECKME: it should probably better return the max comm len from its comm list */314int thread__comm_len(struct thread *thread)315{316 int comm_len = thread__var_comm_len(thread);317 318 if (!comm_len) {319 const char *comm;320 321 down_read(thread__comm_lock(thread));322 comm = __thread__comm_str(thread);323 comm_len = __thread__comm_len(thread, comm);324 up_read(thread__comm_lock(thread));325 }326 327 return comm_len;328}329 330size_t thread__fprintf(struct thread *thread, FILE *fp)331{332 return fprintf(fp, "Thread %d %s\n", thread__tid(thread), thread__comm_str(thread)) +333 maps__fprintf(thread__maps(thread), fp);334}335 336int thread__insert_map(struct thread *thread, struct map *map)337{338 int ret;339 340 ret = unwind__prepare_access(thread__maps(thread), map, NULL);341 if (ret)342 return ret;343 344 return maps__fixup_overlap_and_insert(thread__maps(thread), map);345}346 347struct thread__prepare_access_maps_cb_args {348 int err;349 struct maps *maps;350};351 352static int thread__prepare_access_maps_cb(struct map *map, void *data)353{354 bool initialized = false;355 struct thread__prepare_access_maps_cb_args *args = data;356 357 args->err = unwind__prepare_access(args->maps, map, &initialized);358 359 return (args->err || initialized) ? 1 : 0;360}361 362static int thread__prepare_access(struct thread *thread)363{364 struct thread__prepare_access_maps_cb_args args = {365 .err = 0,366 };367 368 if (dwarf_callchain_users) {369 args.maps = thread__maps(thread);370 maps__for_each_map(thread__maps(thread), thread__prepare_access_maps_cb, &args);371 }372 373 return args.err;374}375 376static int thread__clone_maps(struct thread *thread, struct thread *parent, bool do_maps_clone)377{378 /* This is new thread, we share map groups for process. */379 if (thread__pid(thread) == thread__pid(parent))380 return thread__prepare_access(thread);381 382 if (maps__equal(thread__maps(thread), thread__maps(parent))) {383 pr_debug("broken map groups on thread %d/%d parent %d/%d\n",384 thread__pid(thread), thread__tid(thread),385 thread__pid(parent), thread__tid(parent));386 return 0;387 }388 /* But this one is new process, copy maps. */389 return do_maps_clone ? maps__copy_from(thread__maps(thread), thread__maps(parent)) : 0;390}391 392int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp, bool do_maps_clone)393{394 if (thread__comm_set(parent)) {395 const char *comm = thread__comm_str(parent);396 int err;397 if (!comm)398 return -ENOMEM;399 err = thread__set_comm(thread, comm, timestamp);400 if (err)401 return err;402 }403 404 thread__set_ppid(thread, thread__tid(parent));405 return thread__clone_maps(thread, parent, do_maps_clone);406}407 408void thread__find_cpumode_addr_location(struct thread *thread, u64 addr,409 struct addr_location *al)410{411 size_t i;412 const u8 cpumodes[] = {413 PERF_RECORD_MISC_USER,414 PERF_RECORD_MISC_KERNEL,415 PERF_RECORD_MISC_GUEST_USER,416 PERF_RECORD_MISC_GUEST_KERNEL417 };418 419 for (i = 0; i < ARRAY_SIZE(cpumodes); i++) {420 thread__find_symbol(thread, cpumodes[i], addr, al);421 if (al->map)422 break;423 }424}425 426struct thread *thread__main_thread(struct machine *machine, struct thread *thread)427{428 if (thread__pid(thread) == thread__tid(thread))429 return thread__get(thread);430 431 if (thread__pid(thread) == -1)432 return NULL;433 434 return machine__find_thread(machine, thread__pid(thread), thread__pid(thread));435}436 437int thread__memcpy(struct thread *thread, struct machine *machine,438 void *buf, u64 ip, int len, bool *is64bit)439{440 u8 cpumode = PERF_RECORD_MISC_USER;441 struct addr_location al;442 struct dso *dso;443 long offset;444 445 if (machine__kernel_ip(machine, ip))446 cpumode = PERF_RECORD_MISC_KERNEL;447 448 addr_location__init(&al);449 if (!thread__find_map(thread, cpumode, ip, &al)) {450 addr_location__exit(&al);451 return -1;452 }453 454 dso = map__dso(al.map);455 456 if (!dso || dso__data(dso)->status == DSO_DATA_STATUS_ERROR || map__load(al.map) < 0) {457 addr_location__exit(&al);458 return -1;459 }460 461 offset = map__map_ip(al.map, ip);462 if (is64bit)463 *is64bit = dso__is_64_bit(dso);464 465 addr_location__exit(&al);466 467 return dso__data_read_offset(dso, machine, offset, buf, len);468}469 470void thread__free_stitch_list(struct thread *thread)471{472 struct lbr_stitch *lbr_stitch = thread__lbr_stitch(thread);473 struct stitch_list *pos, *tmp;474 475 if (!lbr_stitch)476 return;477 478 list_for_each_entry_safe(pos, tmp, &lbr_stitch->lists, node) {479 map_symbol__exit(&pos->cursor.ms);480 list_del_init(&pos->node);481 free(pos);482 }483 484 list_for_each_entry_safe(pos, tmp, &lbr_stitch->free_lists, node) {485 list_del_init(&pos->node);486 free(pos);487 }488 489 for (unsigned int i = 0 ; i < lbr_stitch->prev_lbr_cursor_size; i++)490 map_symbol__exit(&lbr_stitch->prev_lbr_cursor[i].ms);491 492 zfree(&lbr_stitch->prev_lbr_cursor);493 free(thread__lbr_stitch(thread));494 thread__set_lbr_stitch(thread, NULL);495}496