Hello, On Mon, Jan 24, 2011 at 05:09:18PM +0100, Bart Van Assche wrote: > Insertion of flush_work_sync() fixes a race - that's a good catch. > flush_work_sync() should be invoked a little earlier though because > the scheduled work may access the queue destroyed by the > crq_queue_destroy(target) call. And the CRQ interrupt should be > disabled from before flush_work_sync() is invoked until after the CRQ > has been destroyed. Heh, I'm a bit out of my depth here. If you know what's necessary, please go ahead and make the change. > Regarding the queue removal: I might have missed something, but why > would you like to remove the vtgtd work queue ? Since the ibmvstgt > driver is a storage target driver, processing latency matters. I'm > afraid that switching from a dedicated queue to the global work queue > will increase processing latency. Having a dedicated workqueue no longer makes any difference regarding processing latency. Each workqueue is mere frontend to the shared worker pool anyway. Dedicated workqueues are now meaningful only as forward progress guarantee, attribute and/or flush domain - IOW, when the workqueue needs to be used during memory reclaim, the work items need to have specific attributes or certain group of work items need to be flushed together. Apart from that, there's virtually no difference between using the system_wq and a dedicated one. As using the system one is usually simpler, it's natural to do that. Thank you. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
