| Date | Tue, 23 Aug 2011 17:52:21 +0200 | From | Oleg Nesterov <> | Subject | Re: [PATCH 06/16] freezer: make exiting tasks properly unfreezable |
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Hi.
Not a comment, but the question. Probably falls into the "read the whole series" category too.
On 08/19, Tejun Heo wrote: > > There's no point in freezing an exiting task.
This is not clear to me. Probably this is fine, I do not know what the callers of freeze_processes() actually expect.
> @@ -915,6 +913,12 @@ NORET_TYPE void do_exit(long code) > > ptrace_event(PTRACE_EVENT_EXIT, code); > > + /* > + * With ptrace notification done, there's no point in freezing from > + * here on. Disallow freezing. > + */ > + current->flags |= PF_NOFREEZE;
OK, but what PF_NOFREEZE actually means?
Apart from "dont try to freeze" it means "no need to freeze", yes?
IOW, try_to_freeze_tasks() can succeed even if we have a lot of exitinig task which can make some activity, say, disk i/o. Is this correct?
Once again, I do not understand the problem-space at all, jus I am curious.
Thanks,
Oleg.
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