On Fri, Sep 17, 2021 at 02:37:19PM +0200, Christoph Hellwig wrote: > On Fri, Sep 17, 2021 at 04:32:15PM +0800, Ming Lei wrote: > > > Is it? For the typical case the second free in blk_cleanp_queue will > > > be bsically free because there is no pending I/O. The only case > > > where that matters if if there is pending passthrough I/O again, > > > which can only happen with SCSI, and even there is highly unusual. > > > > RCU grace period is involved in blk_freeze_queue(). > > where? __percpu_ref_switch_to_atomic(). -- Ming
