Commit fcc95a76 authored Jun 02, 2014 by Bart Van Assche Committed by Christoph Hellwig Jul 17, 2014

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>

parent 89fb4cd1

drivers/scsi/scsi.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -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);
		}

drivers/scsi/scsi_error.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -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;
		}