On Thu, Jul 13, 2017 at 10:14:31AM -0600, Jens Axboe wrote: > On 07/13/2017 10:10 AM, weiping zhang wrote: > > one hw queue only has one hctx, reduce it's number same as nr_hw_queues. > > What happens if a device registers with eg 4 hw queues, then later > calls blk_mq_update_nr_hw_queues()? > your means, 10 cpu, and device has 10 hw queues, but only register 4, and then update it to 10, no place store new hctx. Am i understanding right ? if yes, could you tell me why driver do that ? thanks. -- weiping
