Messages in this thread | | | Subject | Re: rcu: endless stalls | From | Mike Galbraith <> | Date | Mon, 11 Jun 2012 16:22:23 +0200 |
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On Mon, 2012-06-11 at 06:39 -0700, Paul E. McKenney wrote: > On Mon, Jun 11, 2012 at 12:06:16PM +0200, Mike Galbraith wrote: > > Greetings, > > > > I received a report of a 48 core UV box hitting a gripe, taking longer > > than timeout to emit same, so box griped endlessly, forcing reboot. > > So it took minutes to print an RCU CPU stall warning? On only 48 CPUs? > > If so, yow!!!
The report was a tad fuzzy on details, but serial console can take a while at low baud rate, and the box was apparently perma-stalled.
> My guess is that rcu_cpu_stall_suppress must be manipulated atomically > for this to work reliably, for example, using xchg().
Ah, thanks.
-Mike
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