On 06/18, Louis Rilling wrote: > > On 17/06/10 23:36 +0200, Oleg Nesterov wrote: > > On 06/17, Eric W. Biederman wrote: > > > > > > The task->children isn't changed until __unhash_process() which runs > > > after flush_proc_task(). > > > > Yes. But this is only the current implementation detail. > > It would be nice to cleanup the code so that EXIT_DEAD tasks are > > never sit in ->children list. > > > > > So we should be able to come up with > > > a variant of do_wait() that zap_pid_ns_processes can use that does > > > what we need. > > > > See above... > > > > Even if we modify do_wait() or add the new variant, how the caller > > can wait for EXIT_DEAD tasks? I don't think we want to modify > > release_task() to do __wake_up_parent() or something similar. > > Indeed, I was thinking about calling __wake_up_parent() from release_task() > once parent->children becomes empty. > > Not sure about the performance impact though. Maybe some WAIT_NO_CHILDREN flag > in parent->signal could limit it. But if EXIT_DEAD children are removed from > ->children before release_task(), I'm afraid that this becomes impossible. Thinking more, even the current do_wait() from zap_pid_ns_processes() is not really good. Suppose that some none-init thread is ptraced, then zap_pid_ns_processes() will hange until the tracer does do_wait() or exits. Oleg. _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers
