diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/exit.c | 21 | ||||
| -rw-r--r-- | kernel/fork.c | 9 | ||||
| -rw-r--r-- | kernel/signal.c | 38 |
3 files changed, 41 insertions, 27 deletions
diff --git a/kernel/exit.c b/kernel/exit.c index a305043a5d0d..49f279e1a004 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -583,7 +583,6 @@ static void exit_notify(void) * jobs, send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2) */ - current->state = TASK_ZOMBIE; if (current->exit_signal != -1) do_notify_parent(current, current->exit_signal); @@ -592,6 +591,8 @@ static void exit_notify(void) while (!list_empty(¤t->ptrace_children)) zap_thread(list_entry(current->ptrace_children.next,struct task_struct,ptrace_list), current, 1); BUG_ON(!list_empty(¤t->children)); + + current->state = TASK_ZOMBIE; /* * No need to unlock IRQs, we'll schedule() immediately * anyway. In the preemption case this also makes it @@ -697,9 +698,9 @@ asmlinkage long sys_exit_group(int error_code) do_exit(sig->group_exit_code); } -static inline int eligible_child(pid_t pid, int options, task_t *p) +static int eligible_child(pid_t pid, int options, task_t *p) { - if (pid>0) { + if (pid > 0) { if (p->pid != pid) return 0; } else if (!pid) { @@ -725,6 +726,12 @@ static inline int eligible_child(pid_t pid, int options, task_t *p) if (((p->exit_signal != SIGCHLD) ^ ((options & __WCLONE) != 0)) && !(options & __WALL)) return 0; + /* + * Do not consider thread group leaders that are + * in a non-empty thread group: + */ + if (current->tgid != p->tgid && delay_group_leader(p)) + return 0; if (security_ops->task_wait(p)) return 0; @@ -781,8 +788,12 @@ repeat: current->cstime += p->stime + p->cstime; read_unlock(&tasklist_lock); retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0; - if (!retval && stat_addr) - retval = put_user(p->exit_code, stat_addr); + if (!retval && stat_addr) { + if (p->sig->group_exit) + retval = put_user(p->sig->group_exit_code, stat_addr); + else + retval = put_user(p->exit_code, stat_addr); + } if (retval) goto end_wait4; retval = p->pid; diff --git a/kernel/fork.c b/kernel/fork.c index bd902cc45283..5bc7f2a07915 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -628,7 +628,6 @@ static inline int copy_sighand(unsigned long clone_flags, struct task_struct * t atomic_set(&sig->count, 1); sig->group_exit = 0; sig->group_exit_code = 0; - init_completion(&sig->group_exit_done); memcpy(sig->action, current->sig->action, sizeof(sig->action)); sig->curr_target = NULL; init_sigpending(&sig->shared_pending); @@ -672,6 +671,12 @@ static struct task_struct *copy_process(unsigned long clone_flags, */ if (clone_flags & CLONE_THREAD) clone_flags |= CLONE_SIGHAND; + /* + * Detached threads can only be started up within the thread + * group. + */ + if (clone_flags & CLONE_DETACHED) + clone_flags |= CLONE_THREAD; retval = security_ops->task_create(clone_flags); if (retval) @@ -843,6 +848,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, * Let it rip! */ p->tgid = p->pid; + p->group_leader = p; INIT_LIST_HEAD(&p->thread_group); INIT_LIST_HEAD(&p->ptrace_children); INIT_LIST_HEAD(&p->ptrace_list); @@ -870,6 +876,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, goto bad_fork_cleanup_namespace; } p->tgid = current->tgid; + p->group_leader = current->group_leader; list_add(&p->thread_group, ¤t->thread_group); spin_unlock(¤t->sig->siglock); } diff --git a/kernel/signal.c b/kernel/signal.c index 82ef92369ad1..c2dc0ca60a8b 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -251,23 +251,6 @@ void __exit_sighand(struct task_struct *tsk) if (!atomic_read(&sig->count)) BUG(); spin_lock(&sig->siglock); - /* - * Do not let the thread group leader exit until all other - * threads are done: - */ - while (!list_empty(¤t->thread_group) && - current->tgid == current->pid && - atomic_read(&sig->count) > 1) { - - spin_unlock(&sig->siglock); - write_unlock_irq(&tasklist_lock); - - wait_for_completion(&sig->group_exit_done); - - write_lock_irq(&tasklist_lock); - spin_lock(&sig->siglock); - } - spin_lock(&tsk->sigmask_lock); tsk->sig = NULL; if (atomic_dec_and_test(&sig->count)) { @@ -276,10 +259,21 @@ void __exit_sighand(struct task_struct *tsk) flush_sigqueue(&sig->shared_pending); kmem_cache_free(sigact_cachep, sig); } else { - if (!list_empty(¤t->thread_group) && - atomic_read(&sig->count) == 1) - complete(&sig->group_exit_done); - __remove_thread_group(tsk, sig); + struct task_struct *leader = tsk->group_leader; + /* + * If we are the last non-leader member of the thread + * group, and the leader is zombie, then notify the + * group leader's parent process. + * + * (subtle: here we also rely on the fact that if we are the + * thread group leader then we are not zombied yet.) + */ + if (atomic_read(&sig->count) == 1 && + leader->state == TASK_ZOMBIE) { + __remove_thread_group(tsk, sig); + do_notify_parent(leader, leader->exit_signal); + } else + __remove_thread_group(tsk, sig); spin_unlock(&sig->siglock); } clear_tsk_thread_flag(tsk,TIF_SIGPENDING); @@ -1096,6 +1090,8 @@ void do_notify_parent(struct task_struct *tsk, int sig) struct siginfo info; int why, status; + if (delay_group_leader(tsk)) + return; if (sig == -1) BUG(); |