summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorSagi Grimberg <sagig@mellanox.com>2015-01-30 22:17:30 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2015-02-05 22:35:41 -0800
commita3ecefb6bf2ce3d6fbaa1ca0469dcd3f53fce2f4 (patch)
tree93337039efaf37518ab0edc1d0bfe8658d215a31
parentb80e6c5ae062134a0a857d831388d73a52cecbd5 (diff)
downloadlwn-a3ecefb6bf2ce3d6fbaa1ca0469dcd3f53fce2f4.tar.gz
lwn-a3ecefb6bf2ce3d6fbaa1ca0469dcd3f53fce2f4.zip
iser-target: Fix implicit termination of connections
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@gmail.com> Signed-off-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/infiniband/ulp/isert/ib_isert.c45
-rw-r--r--drivers/infiniband/ulp/isert/ib_isert.h1
2 files changed, 36 insertions, 10 deletions
diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c
index e1dd60b8fed9..8019e642d2f5 100644
--- 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_conn *conn)
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);
diff --git a/drivers/infiniband/ulp/isert/ib_isert.h b/drivers/infiniband/ulp/isert/ib_isert.h
index 721bbb7bb279..b233ee5e46b0 100644
--- 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