From cc6b32ee3b914d3036a4d364fd4918b48fc034eb Mon Sep 17 00:00:00 2001 From: Frank Mayhar Date: Thu, 27 Feb 2020 14:59:45 -0500 Subject: scsi: iscsi: Add support for asynchronous iSCSI session destruction iSCSI session destruction can be arbitrarily slow, since it might require network operations and serialization inside the SCSI layer. This patch adds a new user event to trigger the destruction work asynchronously, releasing the rx_queue_mutex as soon as the operation is queued and before it is performed. This change allows other operations to run in other sessions in the meantime, removing one of the major iSCSI bottlenecks for us. To prevent the session from being used after the destruction request, we remove it immediately from the sesslist. This simplifies the locking required during the asynchronous removal. Link: https://lore.kernel.org/r/20200227195945.761719-1-krisman@collabora.com Co-developed-by: Gabriel Krisman Bertazi Co-developed-by: Khazhismel Kumykov Reviewed-by: Lee Duncan Signed-off-by: Gabriel Krisman Bertazi Signed-off-by: Frank Mayhar Signed-off-by: Khazhismel Kumykov Signed-off-by: Martin K. Petersen --- include/scsi/iscsi_if.h | 1 + include/scsi/scsi_transport_iscsi.h | 1 + 2 files changed, 2 insertions(+) (limited to 'include/scsi') diff --git a/include/scsi/iscsi_if.h b/include/scsi/iscsi_if.h index b0e240b10bf9..5225a23f2d0e 100644 --- a/include/scsi/iscsi_if.h +++ b/include/scsi/iscsi_if.h @@ -60,6 +60,7 @@ enum iscsi_uevent_e { ISCSI_UEVENT_LOGOUT_FLASHNODE_SID = UEVENT_BASE + 30, ISCSI_UEVENT_SET_CHAP = UEVENT_BASE + 31, ISCSI_UEVENT_GET_HOST_STATS = UEVENT_BASE + 32, + ISCSI_UEVENT_DESTROY_SESSION_ASYNC = UEVENT_BASE + 33, /* up events */ ISCSI_KEVENT_RECV_PDU = KEVENT_BASE + 1, diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h index 2129dc9e2dec..fa8814245796 100644 --- a/include/scsi/scsi_transport_iscsi.h +++ b/include/scsi/scsi_transport_iscsi.h @@ -226,6 +226,7 @@ struct iscsi_cls_session { struct work_struct unblock_work; struct work_struct scan_work; struct work_struct unbind_work; + struct work_struct destroy_work; /* recovery fields */ int recovery_tmo; -- cgit v1.2.3-59-g8ed1b