Patch "iser-target: Fix implicit termination of connections" has been added to the 3.10-stable tree

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



This is a note to let you know that I've just added the patch titled

    iser-target: Fix implicit termination of connections

to the 3.10-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     iser-target-fix-implicit-termination-of-connections.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.


>From nab@xxxxxxxxxxxxxxx  Tue Feb  3 15:08:43 2015
From: "Nicholas A. Bellinger" <nab@xxxxxxxxxxxxxxx>
Date: Fri, 30 Jan 2015 22:17:30 +0000
Subject: iser-target: Fix implicit termination of connections
To: target-devel <target-devel@xxxxxxxxxxxxxxx>
Cc: Greg-KH <gregkh@xxxxxxxxxxxxxxxxxxx>, stable <stable@xxxxxxxxxxxxxxx>, Sagi Grimberg <sagig@xxxxxxxxxxxx>
Message-ID: <1422656251-29468-12-git-send-email-nab@xxxxxxxxxxxxxxx>


From: Sagi Grimberg <sagig@xxxxxxxxxxxx>

commit b02efbfc9a051b41e71fe8f94ddf967260e024a6 upstream.

In situations such as bond failover, The new session establishment
implicitly invokes the termination of the old connection.

So, we don't want to wait for the old connection wait_conn to completely
terminate before we accept the new connection and post a login response.

The solution is to deffer the comp_wait completion and the conn_put to
a work so wait_conn will effectively be non-blocking (flush errors are
assumed to come very fast).

We allocate isert_release_wq with WQ_UNBOUND and WQ_UNBOUND_MAX_ACTIVE
to spread the concurrency of release works.

Reported-by: Slava Shwartsman <valyushash@xxxxxxxxx>
Signed-off-by: Sagi Grimberg <sagig@xxxxxxxxxxxx>
Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/infiniband/ulp/isert/ib_isert.c |   45 ++++++++++++++++++++++++--------
 drivers/infiniband/ulp/isert/ib_isert.h |    1 
 2 files changed, 36 insertions(+), 10 deletions(-)

--- a/drivers/infiniband/ulp/isert/ib_isert.c
+++ b/drivers/infiniband/ulp/isert/ib_isert.c
@@ -40,6 +40,7 @@ static DEFINE_MUTEX(device_list_mutex);
 static LIST_HEAD(device_list);
 static struct workqueue_struct *isert_rx_wq;
 static struct workqueue_struct *isert_comp_wq;
+static struct workqueue_struct *isert_release_wq;
 static struct kmem_cache *isert_cmd_cache;
 
 static int
@@ -2379,6 +2380,24 @@ isert_free_np(struct iscsi_np *np)
 	kfree(isert_np);
 }
 
+static void isert_release_work(struct work_struct *work)
+{
+	struct isert_conn *isert_conn = container_of(work,
+						     struct isert_conn,
+						     release_work);
+
+	pr_info("Starting release conn %p\n", isert_conn);
+
+	wait_for_completion(&isert_conn->conn_wait);
+
+	mutex_lock(&isert_conn->conn_mutex);
+	isert_conn->state = ISER_CONN_DOWN;
+	mutex_unlock(&isert_conn->conn_mutex);
+
+	pr_info("Destroying conn %p\n", isert_conn);
+	isert_put_conn(isert_conn);
+}
+
 static void isert_wait_conn(struct iscsi_conn *conn)
 {
 	struct isert_conn *isert_conn = conn->context;
@@ -2398,14 +2417,9 @@ static void isert_wait_conn(struct iscsi
 	mutex_unlock(&isert_conn->conn_mutex);
 
 	wait_for_completion(&isert_conn->conn_wait_comp_err);
-	wait_for_completion(&isert_conn->conn_wait);
-
-	mutex_lock(&isert_conn->conn_mutex);
-	isert_conn->state = ISER_CONN_DOWN;
-	mutex_unlock(&isert_conn->conn_mutex);
 
-	pr_info("Destroying conn %p\n", isert_conn);
-	isert_put_conn(isert_conn);
+	INIT_WORK(&isert_conn->release_work, isert_release_work);
+	queue_work(isert_release_wq, &isert_conn->release_work);
 }
 
 static void isert_free_conn(struct iscsi_conn *conn)
@@ -2451,20 +2465,30 @@ static int __init isert_init(void)
 		goto destroy_rx_wq;
 	}
 
+	isert_release_wq = alloc_workqueue("isert_release_wq", WQ_UNBOUND,
+					WQ_UNBOUND_MAX_ACTIVE);
+	if (!isert_release_wq) {
+		pr_err("Unable to allocate isert_release_wq\n");
+		ret = -ENOMEM;
+		goto destroy_comp_wq;
+	}
+
 	isert_cmd_cache = kmem_cache_create("isert_cmd_cache",
 			sizeof(struct isert_cmd), __alignof__(struct isert_cmd),
 			0, NULL);
 	if (!isert_cmd_cache) {
 		pr_err("Unable to create isert_cmd_cache\n");
 		ret = -ENOMEM;
-		goto destroy_tx_cq;
+		goto destroy_release_wq;
 	}
 
 	iscsit_register_transport(&iser_target_transport);
-	pr_debug("iSER_TARGET[0] - Loaded iser_target_transport\n");
+	pr_info("iSER_TARGET[0] - Loaded iser_target_transport\n");
 	return 0;
 
-destroy_tx_cq:
+destroy_release_wq:
+	destroy_workqueue(isert_release_wq);
+destroy_comp_wq:
 	destroy_workqueue(isert_comp_wq);
 destroy_rx_wq:
 	destroy_workqueue(isert_rx_wq);
@@ -2475,6 +2499,7 @@ static void __exit isert_exit(void)
 {
 	flush_scheduled_work();
 	kmem_cache_destroy(isert_cmd_cache);
+	destroy_workqueue(isert_release_wq);
 	destroy_workqueue(isert_comp_wq);
 	destroy_workqueue(isert_rx_wq);
 	iscsit_unregister_transport(&iser_target_transport);
--- a/drivers/infiniband/ulp/isert/ib_isert.h
+++ b/drivers/infiniband/ulp/isert/ib_isert.h
@@ -107,6 +107,7 @@ struct isert_conn {
 	struct completion	conn_wait;
 	struct completion	conn_wait_comp_err;
 	struct kref		conn_kref;
+	struct work_struct	release_work;
 };
 
 #define ISERT_MAX_CQ 64


Patches currently in stable-queue which might be from nab@xxxxxxxxxxxxxxx are

queue-3.10/iser-target-fix-connected_handler-teardown-flow-race.patch
queue-3.10/iscsi-iser-target-initiate-termination-only-once.patch
queue-3.10/ib_isert-add-max_send_sge-2-minimum-for-control-pdu-responses.patch
queue-3.10/iser-target-fix-implicit-termination-of-connections.patch
queue-3.10/iser-target-parallelize-cm-connection-establishment.patch
queue-3.10/vhost-scsi-take-configfs-group-dependency-during-vhost_scsi_set_endpoint.patch
queue-3.10/ib-isert-adjust-cq-size-to-hw-limits.patch
queue-3.10/iser-target-handle-addr_change-event-for-listener-cm_id.patch
queue-3.10/vhost-scsi-add-missing-virtio-scsi-tcm-attribute-conversion.patch
queue-3.10/target-drop-arbitrary-maximum-i-o-size-limit.patch
queue-3.10/tcm_loop-fix-wrong-i_t-nexus-association.patch
queue-3.10/iser-target-fix-flush-disconnect-completion-handling.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]