Hello, On Fri, Jan 20, 2017 at 03:26:06PM +0000, Mel Gorman wrote: > > This translates to queue_work_on(), which has the comment of "We queue > > the work to a specific CPU, the caller must ensure it can't go away.", > > so is this safe? lru_add_drain_all() uses get_online_cpus() around this. > > > > get_online_cpus() would be required. This part of workqueue usage has always been a bit clunky and I should imrpove it but you don't necessarily have to pin the cpus from queueing to execution. You can queue without checking whether the CPU is online and instead synchronize the actual work item execution against cpu offline callback so that if the work item gets executed after offline callback is finished, it becomes a noop. 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>
