// SPDX-License-Identifier: GPL-2.0 #include "../perf.h" #include <errno.h> #include <stdlib.h> #include <stdio.h> #include <string.h> #include <linux/kernel.h> #include "session.h" #include "thread.h" #include "thread-stack.h" #include "util.h" #include "debug.h" #include "namespaces.h" #include "comm.h" #include "map.h" #include "symbol.h" #include "unwind.h" #include <api/fs/fs.h> int thread__init_map_groups(struct thread *thread, struct machine *machine) { pid_t pid = thread->pid_; if (pid == thread->tid || pid == -1) { thread->mg = map_groups__new(machine); } else { struct thread *leader = __machine__findnew_thread(machine, pid, pid); if (leader) { thread->mg = map_groups__get(leader->mg); thread__put(leader); } } return thread->mg ? 0 : -1; } struct thread *thread__new(pid_t pid, pid_t tid) { char *comm_str; struct comm *comm; struct thread *thread = zalloc(sizeof(*thread)); if (thread != NULL) { thread->pid_ = pid; thread->tid = tid; thread->ppid = -1; thread->cpu = -1; INIT_LIST_HEAD(&thread->namespaces_list); INIT_LIST_HEAD(&thread->comm_list); init_rwsem(&thread->namespaces_lock); init_rwsem(&thread->comm_lock); 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); refcount_set(&thread->refcnt, 1); RB_CLEAR_NODE(&thread->rb_node); /* Thread holds first ref to nsdata. */ thread->nsinfo = nsinfo__new(pid); srccode_state_init(&thread->srccode_state); } return thread; err_thread: free(thread); return NULL; } void thread__delete(struct thread *thread) { struct namespaces *namespaces, *tmp_namespaces; struct comm *comm, *tmp_comm; BUG_ON(!RB_EMPTY_NODE(&thread->rb_node)); thread_stack__free(thread); if (thread->mg) { map_groups__put(thread->mg); thread->mg = NULL; } down_write(&thread->namespaces_lock); list_for_each_entry_safe(namespaces, tmp_namespaces, &thread->namespaces_list, list) { list_del(&namespaces->list); namespaces__free(namespaces); } up_write(&thread->namespaces_lock); down_write(&thread->comm_lock); list_for_each_entry_safe(comm, tmp_comm, &thread->comm_list, list) { list_del(&comm->list); comm__free(comm); } up_write(&thread->comm_lock); unwind__finish_access(thread); nsinfo__zput(thread->nsinfo); srccode_state_free(&thread->srccode_state); exit_rwsem(&thread->namespaces_lock); exit_rwsem(&thread->comm_lock); free(thread); } struct thread *thread__get(struct thread *thread) { if (thread) refcount_inc(&thread->refcnt); return thread; } void thread__put(struct thread *thread) { if (thread && refcount_dec_and_test(&thread->refcnt)) { /* * Remove it from the dead_threads list, as last reference * is gone. */ list_del_init(&thread->node); thread__delete(thread); } } struct namespaces *thread__namespaces(const struct thread *thread) { if (list_empty(&thread->namespaces_list)) return NULL; return list_first_entry(&thread->namespaces_list, struct namespaces, list); } static int __thread__set_namespaces(struct thread *thread, u64 timestamp, struct namespaces_event *event) { struct namespaces *new, *curr = thread__namespaces(thread); new = namespaces__new(event); if (!new) return -ENOMEM; list_add(&new->list, &thread->namespaces_list); 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 namespaces_event *event) { int ret; down_write(&thread->namespaces_lock); ret = __thread__set_namespaces(thread, timestamp, event); up_write(&thread->namespaces_lock); return ret; } struct comm *thread__comm(const struct thread *thread) { if (list_empty(&thread->comm_list)) return NULL; return list_first_entry(&thread->comm_list, struct comm, list); } struct comm *thread__exec_comm(const struct thread *thread) { struct comm *comm, *last = NULL; list_for_each_entry(comm, &thread->comm_list, list) { if (comm->exec) return comm; last = comm; } 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) { 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); if (exec) unwind__flush_access(thread); } thread->comm_set = true; return 0; } int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp, bool exec) { int ret; down_write(&thread->comm_lock); ret = ____thread__set_comm(thread, str, timestamp, exec); up_write(&thread->comm_lock); 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->tid) >= (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(const struct thread *thread) { const struct comm *comm = thread__comm(thread); if (!comm) return NULL; return comm__str(comm); } const char *thread__comm_str(const struct thread *thread) { const char *str; down_read((struct rw_semaphore *)&thread->comm_lock); str = __thread__comm_str(thread); up_read((struct rw_semaphore *)&thread->comm_lock); return str; } /* CHECKME: it should probably better return the max comm len from its comm list */ int thread__comm_len(struct thread *thread) { if (!thread->comm_len) { const char *comm = thread__comm_str(thread); if (!comm) return 0; thread->comm_len = strlen(comm); } return thread->comm_len; } size_t thread__fprintf(struct thread *thread, FILE *fp) { return fprintf(fp, "Thread %d %s\n", thread->tid, thread__comm_str(thread)) + map_groups__fprintf(thread->mg, fp); } int thread__insert_map(struct thread *thread, struct map *map) { int ret; ret = unwind__prepare_access(thread, map, NULL); if (ret) return ret; map_groups__fixup_overlappings(thread->mg, map, stderr); map_groups__insert(thread->mg, map); return 0; } static int __thread__prepare_access(struct thread *thread) { bool initialized = false; int err = 0; struct maps *maps = &thread->mg->maps; struct map *map; down_read(&maps->lock); for (map = maps__first(maps); map; map = map__next(map)) { err = unwind__prepare_access(thread, map, &initialized); if (err || initialized) break; } up_read(&maps->lock); return err; } static int thread__prepare_access(struct thread *thread) { int err = 0; if (symbol_conf.use_callchain) err = __thread__prepare_access(thread); return err; } static int thread__clone_map_groups(struct thread *thread, struct thread *parent, bool do_maps_clone) { /* This is new thread, we share map groups for process. */ if (thread->pid_ == parent->pid_) return thread__prepare_access(thread); if (thread->mg == parent->mg) { pr_debug("broken map groups on thread %d/%d parent %d/%d\n", thread->pid_, thread->tid, parent->pid_, parent->tid); return 0; } /* But this one is new process, copy maps. */ return do_maps_clone ? map_groups__clone(thread, parent->mg) : 0; } int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp, bool do_maps_clone) { if (parent->comm_set) { 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->ppid = parent->tid; return thread__clone_map_groups(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->tid) return thread__get(thread); if (thread->pid_ == -1) return NULL; return machine__find_thread(machine, thread->pid_, thread->pid_); } 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; long offset; if (machine__kernel_ip(machine, ip)) cpumode = PERF_RECORD_MISC_KERNEL; if (!thread__find_map(thread, cpumode, ip, &al) || !al.map->dso || al.map->dso->data.status == DSO_DATA_STATUS_ERROR || map__load(al.map) < 0) return -1; offset = al.map->map_ip(al.map, ip); if (is64bit) *is64bit = al.map->dso->is_64_bit; return dso__data_read_offset(al.map->dso, machine, offset, buf, len); }