[SCSI] zfcp: Do not wait for SBALs on stopped queue

Trying to read the FC host statistics on an offline adapter results in
a 5 seconds wait. Reading the statistics tries to issue an exchange
port data request which first waits up to 5 seconds for an entry in
the request queue.

Change the strategy for getting a free SBAL to exit when the queue is
stopped. Reading the statistics will then fail without the wait.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This commit is contained in:
Christof Schmitt 2010-06-21 10:11:32 +02:00 committed by James Bottomley
parent 30b6777b89
commit c2af7545aa
2 changed files with 9 additions and 6 deletions

View File

@ -719,11 +719,6 @@ static struct zfcp_fsf_req *zfcp_fsf_req_create(struct zfcp_qdio *qdio,
zfcp_qdio_req_init(adapter->qdio, &req->qdio_req, req->req_id, sbtype,
req->qtcb, sizeof(struct fsf_qtcb));
if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)) {
zfcp_fsf_req_free(req);
return ERR_PTR(-EIO);
}
return req;
}

View File

@ -251,7 +251,8 @@ static int zfcp_qdio_sbal_check(struct zfcp_qdio *qdio)
struct zfcp_qdio_queue *req_q = &qdio->req_q;
spin_lock_bh(&qdio->req_q_lock);
if (atomic_read(&req_q->count))
if (atomic_read(&req_q->count) ||
!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
return 1;
spin_unlock_bh(&qdio->req_q_lock);
return 0;
@ -274,8 +275,13 @@ int zfcp_qdio_sbal_get(struct zfcp_qdio *qdio)
spin_unlock_bh(&qdio->req_q_lock);
ret = wait_event_interruptible_timeout(qdio->req_q_wq,
zfcp_qdio_sbal_check(qdio), 5 * HZ);
if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
return -EIO;
if (ret > 0)
return 0;
if (!ret) {
atomic_inc(&qdio->req_q_full);
/* assume hanging outbound queue, try queue recovery */
@ -375,6 +381,8 @@ void zfcp_qdio_close(struct zfcp_qdio *qdio)
atomic_clear_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &qdio->adapter->status);
spin_unlock_bh(&qdio->req_q_lock);
wake_up(&qdio->req_q_wq);
qdio_shutdown(qdio->adapter->ccw_device,
QDIO_FLAG_CLEANUP_USING_CLEAR);