From: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/kernel/exit.c | 36 ++++++++++++++++++------------------
1 files changed, 18 insertions(+), 18 deletions(-)
diff -puN kernel/exit.c~release_task-may-sleep kernel/exit.c
--- 25/kernel/exit.c~release_task-may-sleep 2004-07-26 23:24:19.872377536 -0700
+++ 25-akpm/kernel/exit.c 2004-07-26 23:24:19.876376928 -0700
@@ -57,8 +57,6 @@ void release_task(struct task_struct * p
struct dentry *proc_dentry;
repeat:
- BUG_ON(p->state < TASK_ZOMBIE);
-
atomic_dec(&p->user->processes);
spin_lock(&p->proc_lock);
proc_dentry = proc_pid_unhash(p);
@@ -757,9 +755,8 @@ static void exit_notify(struct task_stru
state = TASK_ZOMBIE;
if (tsk->exit_signal == -1 && tsk->ptrace == 0)
state = TASK_DEAD;
- tsk->state = state;
- tsk->flags |= PF_DEAD;
-
+ else
+ tsk->state = state;
/*
* Clear these here so that update_process_times() won't try to deliver
* itimer, profile or rlimit signals to this task while it is in late exit.
@@ -769,19 +766,14 @@ static void exit_notify(struct task_stru
tsk->rlim[RLIMIT_CPU].rlim_cur = RLIM_INFINITY;
/*
- * In the preemption case it must be impossible for the task
- * to get runnable again, so use "_raw_" unlock to keep
- * preempt_count elevated until we schedule().
- *
- * To avoid deadlock on SMP, interrupts must be unmasked. If we
- * don't, subsequently called functions (e.g, wait_task_inactive()
- * via release_task()) will spin, with interrupt flags
- * unwittingly blocked, until the other task sleeps. That task
- * may itself be waiting for smp_call_function() to answer and
- * complete, and with interrupts blocked that will never happen.
+ * Get a reference to it so that we can set the state
+ * as the last step. The state-setting only matters if the
+ * current task is releasing itself, to trigger the final
+ * put_task_struct() in finish_task_switch(). (thread self-reap)
*/
- _raw_write_unlock(&tasklist_lock);
- local_irq_enable();
+ get_task_struct(tsk);
+
+ write_unlock_irq(&tasklist_lock);
list_for_each_safe(_p, _n, &ptrace_dead) {
list_del_init(_p);
@@ -790,9 +782,17 @@ static void exit_notify(struct task_stru
}
/* If the process is dead, release it - nobody will wait for it */
- if (state == TASK_DEAD)
+ if (state == TASK_DEAD) {
release_task(tsk);
+ write_lock_irq(&tasklist_lock);
+ tsk->state = state;
+ _raw_write_unlock(&tasklist_lock);
+ local_irq_enable();
+ } else
+ preempt_disable();
+ tsk->flags |= PF_DEAD;
+ put_task_struct(tsk);
}
asmlinkage NORET_TYPE void do_exit(long code)
_