Messages in this thread | | | Date | Sun, 29 Mar 2015 12:24:40 +0200 | From | Peter Zijlstra <> | Subject | Re: [RFC] vmstat: Avoid waking up idle-cpu to service shepherd work |
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On Sat, Mar 28, 2015 at 02:44:57PM +0100, Peter Zijlstra wrote: > > Now there are few issues I see here (Sorry if they are all imaginary): > > - In case a timer re-arms itself from its handler and is migrated from CPU A to B, what > > happens if the re-armed timer fires before the first handler finishes ? i.e. timer->fn() > > hasn't finished running on CPU A and it has fired again on CPU B. Wouldn't this expose > > us to a lot of other problems? It wouldn't be serialized to itself anymore ? > > What I said above.
What I didn't say, but had thought of is that __run_timer() should skip any timer that has RUNNING set -- for obvious reasons :-)
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