lkml.org 
[lkml]   [2010]   [Mar]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH -mm 0/3] proc: task->signal can't be NULL
On 03/23, Eric W. Biederman wrote:
>
> We need a value that can be computed in constant time, and is not correct
> except when the number of threads is actively changing.

Sure. I was thinking of something like

int get_nr_threads(struct task_struct *tsk)
{
int nr = atomic_read(&task->signal->live);
int reasonable_min = 1;
rcu_read_lock();
if (!thread_group_leader(tsk) && pid_alive(tsk) &&
tsk->group_leader->exit_state)
reasonable_min = 2;
rcu_read_unlock();
return max(nr, reasonable_min);
}
but as I said this doesn't look nice at all.

> > OK. Let's keep this counter as "int nr_thread".
> >
> > Besides, when I tried to re-implement get_nr_threads() using signal->live
> > I got the really ugly result ;)
>
> Sounds good.

OK, please see the "final" patch I am going to send...

Oleg.



\
 
 \ /
  Last update: 2010-03-24 18:53    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site