On Wed, Aug 15, 2012 at 10:05:28AM +0100, Mel Gorman wrote: > On Tue, Aug 14, 2012 at 05:11:13PM -0300, Rafael Aquini wrote: > > On Tue, Aug 14, 2012 at 10:51:39PM +0300, Michael S. Tsirkin wrote: > > > What I think you should do is use rcu for access. > > > And here sync rcu before freeing. > > > Maybe an overkill but at least a documented synchronization > > > primitive, and it is very light weight. > > > > > > > I liked your suggestion on barriers, as well. > > > > I have not thought about this as deeply as I shouold but is simply rechecking > the mapping under the pages_lock to make sure the page is still a balloon > page an option? i.e. use pages_lock to stabilise page->mapping.
To clarify, are you concerned about cost of rcu_read_lock for non balloon pages? > -- > Mel Gorman > SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
