scsi: remove two cancel_delayed_work() calls from the mid-layer

scsi_put_command() is either invoked before blk_start_request() or
after block layer processing has completed.  scsi_cmnd.abort_work
is scheduled from inside the SCSI timeout handler.  The block layer
guarantees that either the regular completion handler
(softirq_done_fn()) or the timeout handler (rq_timed_out_fn()) is
invoked but not both. This means that scsi_put_command() is never
invoked while abort_work is scheduled.  Hence remove the
cancel_delayed_work() call from scsi_put_command().

Similarly, scsi_abort_command() is only invoked from the SCSI
timeout handler. If scsi_abort_command() is invoked for a SCSI
command with the SCSI_EH_ABORT_SCHEDULED flag set this means that
scmd_eh_abort_handler() has already invoked scsi_queue_insert() and
hence that scsi_cmnd.abort_work is no longer pending. Hence also
remove the cancel_delayed_work() call from scsi_abort_command().

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Bart Van Assche 2014-06-02 11:50:52 +02:00 committed by Christoph Hellwig
parent 89fb4cd1f7
commit fcc95a7634
2 changed files with 2 additions and 2 deletions

View File

@ -334,7 +334,7 @@ void scsi_put_command(struct scsi_cmnd *cmd)
list_del_init(&cmd->list);
spin_unlock_irqrestore(&cmd->device->list_lock, flags);
cancel_delayed_work(&cmd->abort_work);
BUG_ON(delayed_work_pending(&cmd->abort_work));
__scsi_put_command(cmd->device->host, cmd);
}

View File

@ -193,7 +193,7 @@ scsi_abort_command(struct scsi_cmnd *scmd)
SCSI_LOG_ERROR_RECOVERY(3,
scmd_printk(KERN_INFO, scmd,
"scmd %p previous abort failed\n", scmd));
cancel_delayed_work(&scmd->abort_work);
BUG_ON(delayed_work_pending(&scmd->abort_work));
return FAILED;
}