// 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) { char *comm_str; struct comm *comm; RC_STRUCT(thread) *_thread = zalloc(sizeof(*_thread)); struct thread *thread; if (ADD_RC_CHK(thread, _thread) != NULL) { 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)); comm_str = malloc(32); if (!comm_str) goto err_thread; snprintf(comm_str, 32, ":%d", tid); comm = comm__new(comm_str, 0, false); free(comm_str); 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: free(thread); return NULL; } 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); 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; maps__fixup_overlappings(thread__maps(thread), map, stderr); return maps__insert(thread__maps(thread), map); } static int __thread__prepare_access(struct thread *thread) { bool initialized = false; int err = 0; struct maps *maps = thread__maps(thread); struct map_rb_node *rb_node; down_read(maps__lock(maps)); maps__for_each_entry(maps, rb_node) { err = unwind__prepare_access(thread__maps(thread), rb_node->map, &initialized); if (err || initialized) break; } up_read(maps__lock(maps)); return err; } static int thread__prepare_access(struct thread *thread) { int err = 0; if (dwarf_callchain_users) err = __thread__prepare_access(thread); return 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 (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__clone(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.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; 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) { 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); } zfree(&lbr_stitch->prev_lbr_cursor); free(thread__lbr_stitch(thread)); thread__set_lbr_stitch(thread, NULL); }