Messages in this thread | | | Subject | Re: + generic-ipi-fix-the-race-between-generic_smp_call_function_-and-hotplug_cfd.patch added to -mm tree | From | Suresh Siddha <> | Date | Mon, 21 Sep 2009 22:32:33 -0700 |
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On Sun, 2009-09-20 at 21:04 -0700, Xiao Guangrong wrote: > > Suresh Siddha wrote: > > > > I am referring to the missing csd_lock_wait() here that you had in the > > first version of your patch. Let's say, if cpu X is going offline, we > > need to ensure that the smp_call_function() initiated by cpu X (i.e., > > smp_call_function IPI sent to some other cpu's from cpu X) got serviced > > before cpu X goes offline. We can't do csd_lock_wait() here, as that > > might deadlock (as all the other cpu's are already in stop machine with > > interrupts disabled). > > > > It not happen because the preemption is disabled while send IPI request and > can't schedule to stop machine path, it also stop cpu down.
Xiao, I am getting confused. I am referring to case '1' mentioned by you here http://marc.info/?l=linux-kernel&m=125265516529139&w=2
thanks, suresh
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