On Sun, Mar 30, 2014 at 08:57:51AM -0400, Tejun Heo wrote: > On Thu, Mar 27, 2014 at 06:21:00PM +0100, Frederic Weisbecker wrote: > > The workqueues are all listed in a global list protected by a big mutex. > > And this big mutex is used in apply_workqueue_attrs() as well. > > > > Now as we plan to implement a directory to control the cpumask of > > all non-ABI unbound workqueues, we want to be able to iterate over all > > unbound workqueues and call apply_workqueue_attrs() for each of > > them with the new cpumask. > > > > But the risk for a deadlock is on the way: we need to iterate the list > > of workqueues under wq_pool_mutex. But then apply_workqueue_attrs() > > itself calls wq_pool_mutex. > > Wouldn't the right thing to do would be factoring out > apply_workqueue_attrs_locked()? It's cleaner to block out addition of > new workqueues while the masks are being updated anyway.
I'm not quite sure I get what you suggest. Do you mean have apply_workqueue_attrs_locked() calling apply_workqueue_attrs() under the lock on this patch? Thanks. -- 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/
