Hello, On Thu, Oct 22, 2015 at 09:41:11AM -0500, Christoph Lameter wrote: > > If this is actually a legit busy-waiting cyclic dependency, just let > > me know. > > There is no dependency of the vmstat updater on anything. > They can run anytime. If there is a dependency then its created by the > kworker subsystem itself. Sure, the other direction is from workqueue concurrency detection. I was asking whether a work item can busy-wait on vmstat_update work item cuz that's what confuses workqueue. Looking at the original dump, the pool has two idle workers indicating that the workqueue wasn't short of execution resources and it really looks like that work item was live-locking the pool. I'll go ahead and add WQ_IMMEDIATE. Thanks. -- tejun -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>