Carsten Otte wrote: > Laurent Vivier wrote: > >> This patches can be applied only on kvm-updates-2.6.24 and kvm-updates-2.6.25 >> as it needs smp_call_function_mask(). >> > There's one thing I don't understand: How is this locked versus cpu > hotplug? Isn't there an obvious race involved where a cpu unplugged > after cpu_set()? > >
A cpu unplug first evicts all tasks from the victim cpu. During this process, it calls kvm via a hotplug notifier, which notifier calls vcpu_clear() for all vcpus that are resident on that cpu. So after it runs, there won't be any vcpus on the dead cpu. The notifier is called from within stop_machine_run(), which ensures that no task is running on any cpu, so by the time the cpu is being unplugged, any concurrent call to kvm_flush_remote_tlbs() will have ended. It's a miracle that it works. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
