Messages in this thread | | | Date | Mon, 18 Jun 2007 08:43:43 +0200 | From | Ingo Molnar <> | Subject | Re: [BUG] long freezes on thinkpad t60 |
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* Miklos Szeredi <miklos@szeredi.hu> wrote:
> > could you try the quick hack below, ontop of cfs-v17? It adds two > > things to wait_task_inactive(): > > > > - a cond_resched() [in case you are running !PREEMPT] > > > > - use MONITOR+MWAIT to monitor memory transactions to the rq->curr > > cacheline. This should make the polling loop definitely fair. > > Is it not possible for the mwait to get stuck?
it is - when the other CPU does nothing.
> > If this solves the problem on your box then i'll do a proper fix and > > introduce a cpu_relax_memory_change(*addr) type of API to around > > monitor/mwait. This patch boots fine on my T60 - but i never saw > > your problem. > > Yes, the patch does make the pauses go away. In fact just the > smp_mb() seems to suffice.
cool! Could you send me the smallest patch you tried that still made the hangs go away?
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