Messages in this thread | | | Date | Sun, 11 Mar 2012 18:49:53 +0100 | From | Oleg Nesterov <> | Subject | self_exec_id/parent_exec_id && CLONE_PARENT |
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(change subject)
On 03/11, Oleg Nesterov wrote: > > Well, I don't think it is right to add this counter into task_struct. > > It should be per-process, signal_struct makes more sense. Or may be > mm_struct. > > Btw this is also true for parent_exec_id/self_exec_id, but this is > another story.
In fact I think it would be nice to kill parent_exec_id/self_exec_id.
Afaics, this only problem is clone(CLONE_PARENT | SIGXXX). I expect the answer is "no, can break existing applications", but I'll ask anyway.
Can't we change this? IOW, can't we modify copy_process
- p->exit_signal = (clone_flags & CLONE_THREAD) ? -1 : (clone_flags & CSIGNAL); + p->exit_signal = + (clone_flags & CLONE_THREAD) ? -1 : + (clobe_flags & CLONE_PARENT) ? current->group_leader->exit_signal : + (clone_flags & CSIGNAL);
(or simply use SIGCHLD instead of group_leader->exit_signal).
Then we can kill parent_exec_id/self_exec_id if me modify de_thread() to set ->exit_signal = SIGCHLD for every child.
I am also asking because the change above looks like the fix to me. The child must not control its ->exit_signal, it is the parent who decides which signal the child should use for notification.
And to me, clone(CLONE_PARENT | SIGXXX) looks like a violation of rule above.
Oleg.
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