From 1d726aa6ef574afbaa90a2c46286d94e55d864b8 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Wed, 1 Jul 2020 14:47:47 -0500 Subject: [PATCH] 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: Mike Christie Signed-off-by: Martin K. Petersen --- drivers/scsi/scsi_transport_iscsi.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c index d4da7d21530d..a55ea229fce8 100644 --- a/drivers/scsi/scsi_transport_iscsi.c +++ b/drivers/scsi/scsi_transport_iscsi.c @@ -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.