Change Details

When we suspend, we need to tear down all the qpairs. We call nvme_admin_qpair_abort_aers with the admin qpair lock held, but the tracker it will call for the pending AER also locks it (recursively) hitting an assert. This routine is called without the qpair lock held when we destroy the device entirely in a number of places. Add an assert to this effect and drop the qpair lock before calling it. nvme_admin_qpair_abort_aers copes with the lack of lock by restarting its scan of the outstanding list after calling the manual completion, so it's always safe to call w/o the lock held. Sponsored by: Netflix

Currently, when we suspend, we need to tear down all the qpairs. We call nvme_admin_qpair_abort_aers with the admin qpair lock held, but the tracker it will call for the pending AER also locks it (recursively) hitting an assert. This routine is called without the qpair lock held when we destroy the device entirely in a number of places. Add an assert to this effect and drop the qpair lock before calling it. nvme_admin_qpair_abort_aers then locks the qpair lock to traverse the list, dropping it around calls to nvme_qpair_complete_tracker, and restarting the list scan after picking it back up. Note: If interrupts are still running, there's a tiny window for these AERs: If one fires just an instant after we manually complete it, then we'll be fine: we set the state of the queue to 'waiting' and we ignore interrupts while 'waiting'. We know we'll destroy all the queue state with these pending interrupts before looking at them again and we know all the TRs will have been completed or rescheduled. Also, tidy up the failure case as well: failing a queue is a superset of disabling it, so no need to call disable first. This solves solves some locking issues. Set the qpair state of failed queues to RECOVERY_FAILED and stop scheduling the watchdog. Assert we're not failed when we're enabling a qpair. Next, kill the pre/post reset stuff. It's completely bogus since we disable the qparis, we don't need to also hold the lock through the reset: disabling will cause the ISR to return early. This keeps us from recursing on the recovery lock when resuming. Finally, kill NVME_RESET_2X. It'S been a major release since we put it in and nobody has used it as far as I can tell. And it was a motivator for the pre/post uglification. These are all interrelated, so need to be done at the same time.

WCurrently, when we suspend, we need to tear down all the qpairs. We call nvme_admin_qpair_abort_aers with the admin qpair lock held, but the tracker it will call for the pending AER also locks it (recursively) hitting an assert. This routine is called without the qpair lock held when we destroy the device entirely in a number of places. Add an assert to this effect and drop the qpair lock before calling it. nvme_admin_qpair_abort_aers copes withthen locks the lack ofqpair lock by restartingto traverse the its scan of the outstandlist, dropping list afterit around calling the manual s to nvme_qpair_completion,ete_tracker, and so it's always safe to call w/o the lock heldrestarting the list scan after picking it back up. Sponsored by: NetflixNote: If interrupts are still running, there's a tiny window for these AERs: If one fires just an instant after we manually complete it, then we'll be fine: we set the state of the queue to 'waiting' and we ignore interrupts while 'waiting'. We know we'll destroy all the queue state with these pending interrupts before looking at them again and we know all the TRs will have been completed or rescheduled. Also, tidy up the failure case as well: failing a queue is a superset of disabling it, so no need to call disable first. This solves solves some locking issues. Set the qpair state of failed queues to RECOVERY_FAILED and stop scheduling the watchdog. Assert we're not failed when we're enabling a qpair. Next, kill the pre/post reset stuff. It's completely bogus since we disable the qparis, we don't need to also hold the lock through the reset: disabling will cause the ISR to return early. This keeps us from recursing on the recovery lock when resuming. Finally, kill NVME_RESET_2X. It'S been a major release since we put it in and nobody has used it as far as I can tell. And it was a motivator for the pre/post uglification. These are all interrelated, so need to be done at the same time.