Messages in this thread | | | Date | Wed, 30 Jul 2008 22:13:20 +0400 | From | Oleg Nesterov <> | Subject | Re: [PATCH 3/3] wait_task_inactive: don't use the dummy version when !SMP && PREEMPT |
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On 07/30, Linus Torvalds wrote: > > On Wed, 30 Jul 2008, Oleg Nesterov wrote: > > > > The patch looks monstrous because it moves the (unchanged) definition > > of wait_task_inactive() outside of "#ifdef CONFIG_SMP", but it is quite > > trivial. > > Hmm. Doesn't this just deadlock in UP (PREEMPT) if wait_task_interactive() > is ever called from a no-preempt context?
Given that it calls schedule_timeout_uninterruptible(), it can't be used from the no-preempt context,
> And if that's never the case, the comment should be updated to reflect > that (right now it says that it's only invalid to call it with interrupts > disabled to avoid cross-IPI deadlocks).
Yes, I think this function is might_sleep(),
> Oh, and shouldn't it do a "yield()" instead of a cpu_relax() on UP?
I _think_ that rq->curr must be == current without CONFIG_SMP, but
> and I want to understand why it's > ok (_if_ it's ok).
me too.
Hopefully Ingo can ack/nack.
Oleg.
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