On Tue, Jun 17, 2014 at 02:39:46PM -0500, Christoph Lameter wrote: > On Tue, 17 Jun 2014, Paul E. McKenney wrote: > > > We are talking about one CPU initializing all CPUs' portions of > > dynamically allocated per-CPU memory, so there really is more than > > one CPU involved. > > Well that only occurs on initialization before the address of the > struct that contains the offset is available to other processors.
So does assignment of the pointer in most cases. > During operation the percpu area functions like a single processor. And > its designed that way to avoid synchronization issues and take full > advantage of *no* synchronization for full speed. We compromise on that > for statistics but that is only read access. And during normal operation, it doesn't make any difference for anything except alpha. It's about making the initialization part easier / safer. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
