On 2011-02-07 16:52, Avi Kivity wrote: > On 02/07/2011 05:38 PM, Jan Kiszka wrote: >>> >>> I don't know as it is allowed to sleep, it doesn't call any sleeping >>> functions to my knowledge. What worries me in the RT case is that the >>> spinlock acquired for hardware_enable might be preempted and run on >>> another CPU, which obviously isn't what you want. >> >> I see now, there are calls to raw_smp_processor_id. >> >> I think it's best to make this a raw lock. At this chance, some >> read-only users of vm_list should be rcu'ified. Will have a look. > > vm_list is rarely used, for either read or write. I don't see the need > to rcu it. Avoid that code under this lock expands the preempt-disabled period, specifically under -rt, and specifically as the number of objects over which we loop is user-defined. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
