On 12/14/18 4:39 AM, Ming Lei wrote: > Hi, > > The 1st patch provides support debugfs on rq_qos. > > The 2nd patch exports blk-wbt's internal states via debugfs. This is great! We do indeed badly need it, not just to diagnose hangs, but also to get a better idea of what is going on. I've got a wbt-trace script that I use, but this is easier for a quick inspection. -- Jens Axboe