On Fri, Sep 08, 2017 at 04:52:22PM -0700, Bart Van Assche wrote: > The blk-mq core keeps track of the number of request queue users > through q->q_usage_count. Make it possible to switch this counter > to atomic mode from the context of the block layer power management > code by introducing percpu_ref_switch_to_atomic_nowait(). Do you ever have to switch back? If so, how do you know whether the previous transition finished? Thanks. -- tejun
