Commit 1d726aa6 authored by Mike Christie's avatar Mike Christie Committed by Martin K. Petersen
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scsi: iscsi: Optimize work queue flush use 

There is no need for one session to flush the entire iscsi_eh_timer_workq
when removing/unblocking a session. During removal we need to make sure our
works are not running anymore. And iscsi_unblock_session only needs to make
sure its work is done. The unblock work function will flush/cancel the
works it has conflicts with.

Link: https://lore.kernel.org/r/1593632868-6808-3-git-send-email-michael.christie@oracle.com


Signed-off-by: default avatarMike Christie <michael.christie@oracle.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent e463f96b

drivers/scsi/scsi_transport_iscsi.c

+7 −8
Original line number Diff line number Diff line
@@ -1978,10 +1978,11 @@ void iscsi_unblock_session(struct iscsi_cls_session *session) 
{

	queue_work(iscsi_eh_timer_workq, &session->unblock_work);

	/*

	 * make sure all the events have completed before tell the driver

	 * it is safe

	 * Blocking the session can be done from any context so we only

	 * queue the block work. Make sure the unblock work has completed

	 * because it flushes/cancels the other works and updates the state.

	 */

	flush_workqueue(iscsi_eh_timer_workq);

	flush_work(&session->unblock_work);

}

EXPORT_SYMBOL_GPL(iscsi_unblock_session);
@@ -2205,11 +2206,9 @@ void iscsi_remove_session(struct iscsi_cls_session *session) 
	list_del(&session->sess_list);

	spin_unlock_irqrestore(&sesslock, flags);



	/* make sure there are no blocks/unblocks queued */

	flush_workqueue(iscsi_eh_timer_workq);

	/* make sure the timedout callout is not running */

	if (!cancel_delayed_work(&session->recovery_work))

		flush_workqueue(iscsi_eh_timer_workq);

	flush_work(&session->block_work);

	flush_work(&session->unblock_work);

	cancel_delayed_work_sync(&session->recovery_work);

	/*

	 * If we are blocked let commands flow again. The lld or iscsi

	 * layer should set up the queuecommand to fail commands.