On Fri, Oct 20, 2017 at 04:45:23PM +0200, Christoph Hellwig wrote: > We need to look for an active PM request until the next softbarrier > instead of looking for the first non-PM request. Otherwise any cause > of request reordering might starve the PM request(s).
Hi Christoph, Could you share us how the starve is caused? Looks all PM request is run via scsi_execute(), and the caller is always waiting for the completion of PM request. Especially PM request is run after SCSI device is in quiesce state, during that time, no normal(non-preempt) request can enter queue after the making quiesce safe patchset is merged. -- Ming
