2007-11-23 20:00:52

by Oleg Nesterov

Subject: [PATCH -mm 1/2] wait_task_stopped: remove unneeded delay_group_leader check

wait_task_stopped() doesn't need the "delay_group_leader" parameter. If the
child is not traced it must be a group leader. With or without subthreads
->group_stop_count == 0 when the whole task is stopped.

Signed-off-by: Oleg Nesterov <[email protected]>

--- PT/kernel/exit.c~5_ck_group_stop 2007-11-22 19:08:43.000000000 +0300
+++ PT/kernel/exit.c 2007-11-23 20:31:21.000000000 +0300
@@ -1348,7 +1348,7 @@ static int wait_task_zombie(struct task_
* the lock and this task is uninteresting. If we return nonzero, we have
* released the lock and the system call should return.
*/
-static int wait_task_stopped(struct task_struct *p, int delayed_group_leader,
+static int wait_task_stopped(struct task_struct *p,
int noreap, struct siginfo __user *infop,
int __user *stat_addr, struct rusage __user *ru)
{
@@ -1362,8 +1362,7 @@ static int wait_task_stopped(struct task
if (unlikely(!is_task_stopped_or_traced(p)))
goto unlock_sig;

- if (delayed_group_leader && !(p->ptrace & PT_PTRACED) &&
- p->signal->group_stop_count > 0)
+ if (!(p->ptrace & PT_PTRACED) && p->signal->group_stop_count > 0)
/*
* A group stop is in progress and this is the group leader.
* We won't report until all threads have stopped.
@@ -1519,7 +1518,7 @@ repeat:
!(options & WUNTRACED))
continue;

- retval = wait_task_stopped(p, ret == 2,
+ retval = wait_task_stopped(p,
(options & WNOWAIT), infop,
stat_addr, ru);
} else if (p->exit_state == EXIT_ZOMBIE) {

2007-11-24 08:48:19

by Mika Penttilä

Subject: Re: [PATCH -mm 1/2] wait_task_stopped: remove unneeded delay_group_leader check

> wait_task_stopped() doesn't need the "delay_group_leader" parameter. If the
> child is not traced it must be a group leader. With or without subthreads
>
What do you mean "has to be a group leader"? It could be a stopped thread.

> ->group_stop_count == 0 when the whole task is stopped.
>
>
> Signed-off-by: Oleg Nesterov <[email protected]>
>
> --- PT/kernel/exit.c~5_ck_group_stop 2007-11-22 19:08:43.000000000 +0300
> +++ PT/kernel/exit.c 2007-11-23 20:31:21.000000000 +0300
> @@ -1348,7 +1348,7 @@ static int wait_task_zombie(struct task_
> * the lock and this task is uninteresting. If we return nonzero, we have
> * released the lock and the system call should return.
> */
> -static int wait_task_stopped(struct task_struct *p, int delayed_group_leader,
> +static int wait_task_stopped(struct task_struct *p,
> int noreap, struct siginfo __user *infop,
> int __user *stat_addr, struct rusage __user *ru)
> {
> @@ -1362,8 +1362,7 @@ static int wait_task_stopped(struct task
> if (unlikely(!is_task_stopped_or_traced(p)))
> goto unlock_sig;
>
> - if (delayed_group_leader && !(p->ptrace & PT_PTRACED) &&
> - p->signal->group_stop_count > 0)
> + if (!(p->ptrace & PT_PTRACED) && p->signal->group_stop_count > 0)
> /*
> * A group stop is in progress and this is the group leader.
> * We won't report until all threads have stopped.
> @@ -1519,7 +1518,7 @@ repeat:
> !(options & WUNTRACED))
> continue;
>
> - retval = wait_task_stopped(p, ret == 2,
> + retval = wait_task_stopped(p,
> (options & WNOWAIT), infop,
> stat_addr, ru);
> } else if (p->exit_state == EXIT_ZOMBIE) {
>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
>
>
>

2007-12-11 01:45:47

by Roland McGrath

Subject: Re: [PATCH -mm 1/2] wait_task_stopped: remove unneeded delay_group_leader check

Your change looks correct to me.


Thanks,
Roland