Re: [RFC][PATCH 0/5] Signal scalability series

Oleg Nesterov
2011-10-04T17:44:16Z

On 10/04, Thomas Gleixner wrote:
>
> The main nuisance of sighand->siglock is the exit race protection and
> that's why we need to take it for evrything and some more.
>
> In order to distangle the posix-(cpu)-timer and other stuffs
> protection from that single lock, you need to introduce "independent"
> locks

Yes. And there is another (much more important imho) reason.

We need a separate lock to protect thread_group/children to avoid
tasklist_lock in exit_notify/wait/etc. And probably it should be
sleepable.

Oleg.