[SCSI] iscsi lib: have lib create work queue for transmitting IO

We were using the shost work queue which ended up being
a little akward since all iscsi hosts need a thread for
scanning, but only drivers hooked into libiscsi need
a workqueue for transmitting. So this patch moves the
xmit workqueue to the lib.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This commit is contained in:
Mike Christie 2009-03-05 14:46:03 -06:00 committed by James Bottomley
parent 06d25af4ed
commit 32ae763e3f
7 changed files with 48 additions and 16 deletions

View File

@ -404,7 +404,7 @@ iscsi_iser_session_create(struct iscsi_endpoint *ep,
struct Scsi_Host *shost;
struct iser_conn *ib_conn;
shost = iscsi_host_alloc(&iscsi_iser_sht, 0, ISER_DEF_CMD_PER_LUN);
shost = iscsi_host_alloc(&iscsi_iser_sht, 0, ISER_DEF_CMD_PER_LUN, 1);
if (!shost)
return NULL;
shost->transportt = iscsi_iser_scsi_transport;

View File

@ -661,7 +661,7 @@ void iser_snd_completion(struct iser_desc *tx_desc)
if (resume_tx) {
iser_dbg("%ld resuming tx\n",jiffies);
scsi_queue_work(conn->session->host, &conn->xmitwork);
iscsi_conn_queue_work(conn);
}
if (tx_desc->type == ISCSI_TX_CONTROL) {

View File

@ -171,7 +171,7 @@ struct cxgb3i_hba *cxgb3i_hba_host_add(struct cxgb3i_adapter *snic,
shost = iscsi_host_alloc(&cxgb3i_host_template,
sizeof(struct cxgb3i_hba),
CXGB3I_SCSI_QDEPTH_DFLT);
CXGB3I_SCSI_QDEPTH_DFLT, 1);
if (!shost) {
cxgb3i_log_info("iscsi_host_alloc failed.\n");
return NULL;

View File

@ -479,7 +479,7 @@ void cxgb3i_conn_tx_open(struct s3_conn *c3cn)
cxgb3i_tx_debug("cn 0x%p.\n", c3cn);
if (conn) {
cxgb3i_tx_debug("cn 0x%p, cid %d.\n", c3cn, conn->id);
scsi_queue_work(conn->session->host, &conn->xmitwork);
iscsi_conn_queue_work(conn);
}
}

View File

@ -166,7 +166,7 @@ static void iscsi_sw_tcp_write_space(struct sock *sk)
tcp_sw_conn->old_write_space(sk);
ISCSI_SW_TCP_DBG(conn, "iscsi_write_space\n");
scsi_queue_work(conn->session->host, &conn->xmitwork);
iscsi_conn_queue_work(conn);
}
static void iscsi_sw_tcp_conn_set_callbacks(struct iscsi_conn *conn)
@ -777,7 +777,7 @@ iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
return NULL;
}
shost = iscsi_host_alloc(&iscsi_sw_tcp_sht, 0, qdepth);
shost = iscsi_host_alloc(&iscsi_sw_tcp_sht, 0, qdepth, 1);
if (!shost)
return NULL;
shost->transportt = iscsi_sw_tcp_scsi_transport;

View File

@ -76,6 +76,15 @@ static int iscsi_sna_lte(u32 n1, u32 n2)
(n1 > n2 && (n2 - n1 < SNA32_CHECK)));
}
inline void iscsi_conn_queue_work(struct iscsi_conn *conn)
{
struct Scsi_Host *shost = conn->session->host;
struct iscsi_host *ihost = shost_priv(shost);
queue_work(ihost->workq, &conn->xmitwork);
}
EXPORT_SYMBOL_GPL(iscsi_conn_queue_work);
void
iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
{
@ -103,8 +112,7 @@ iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
if (!list_empty(&session->leadconn->xmitqueue) ||
!list_empty(&session->leadconn->mgmtqueue)) {
if (!(session->tt->caps & CAP_DATA_PATH_OFFLOAD))
scsi_queue_work(session->host,
&session->leadconn->xmitwork);
iscsi_conn_queue_work(session->leadconn);
}
}
}
@ -586,7 +594,7 @@ __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
goto free_task;
} else
scsi_queue_work(conn->session->host, &conn->xmitwork);
iscsi_conn_queue_work(conn);
return task;
@ -1160,7 +1168,7 @@ void iscsi_requeue_task(struct iscsi_task *task)
struct iscsi_conn *conn = task->conn;
list_move_tail(&task->running, &conn->requeue);
scsi_queue_work(conn->session->host, &conn->xmitwork);
iscsi_conn_queue_work(conn);
}
EXPORT_SYMBOL_GPL(iscsi_requeue_task);
@ -1413,7 +1421,7 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
goto prepd_reject;
}
} else
scsi_queue_work(session->host, &conn->xmitwork);
iscsi_conn_queue_work(conn);
session->queued_cmdsn++;
spin_unlock(&session->lock);
@ -1631,9 +1639,12 @@ static void fail_all_commands(struct iscsi_conn *conn, unsigned lun,
void iscsi_suspend_tx(struct iscsi_conn *conn)
{
struct Scsi_Host *shost = conn->session->host;
struct iscsi_host *ihost = shost_priv(shost);
set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
if (!(conn->session->tt->caps & CAP_DATA_PATH_OFFLOAD))
scsi_flush_work(conn->session->host);
flush_workqueue(ihost->workq);
}
EXPORT_SYMBOL_GPL(iscsi_suspend_tx);
@ -1641,7 +1652,7 @@ static void iscsi_start_tx(struct iscsi_conn *conn)
{
clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
if (!(conn->session->tt->caps & CAP_DATA_PATH_OFFLOAD))
scsi_queue_work(conn->session->host, &conn->xmitwork);
iscsi_conn_queue_work(conn);
}
static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
@ -2046,12 +2057,14 @@ EXPORT_SYMBOL_GPL(iscsi_host_add);
* @sht: scsi host template
* @dd_data_size: driver host data size
* @qdepth: default device queue depth
* @xmit_can_sleep: bool indicating if LLD will queue IO from a work queue
*
* This should be called by partial offload and software iscsi drivers.
* To access the driver specific memory use the iscsi_host_priv() macro.
*/
struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
int dd_data_size, uint16_t qdepth)
int dd_data_size, uint16_t qdepth,
bool xmit_can_sleep)
{
struct Scsi_Host *shost;
struct iscsi_host *ihost;
@ -2063,13 +2076,25 @@ struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
if (qdepth == 0)
qdepth = ISCSI_DEF_CMD_PER_LUN;
shost->cmd_per_lun = qdepth;
ihost = shost_priv(shost);
if (xmit_can_sleep) {
snprintf(ihost->workq_name, sizeof(ihost->workq_name),
"iscsi_q_%d", shost->host_no);
ihost->workq = create_singlethread_workqueue(ihost->workq_name);
if (!ihost->workq)
goto free_host;
}
spin_lock_init(&ihost->lock);
ihost->state = ISCSI_HOST_SETUP;
ihost->num_sessions = 0;
init_waitqueue_head(&ihost->session_removal_wq);
return shost;
free_host:
scsi_host_put(shost);
return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_host_alloc);
@ -2101,6 +2126,8 @@ void iscsi_host_remove(struct Scsi_Host *shost)
flush_signals(current);
scsi_remove_host(shost);
if (ihost->workq)
destroy_workqueue(ihost->workq);
}
EXPORT_SYMBOL_GPL(iscsi_host_remove);

View File

@ -318,6 +318,9 @@ struct iscsi_host {
spinlock_t lock;
int num_sessions;
int state;
struct workqueue_struct *workq;
char workq_name[20];
};
/*
@ -343,7 +346,8 @@ extern int iscsi_host_get_param(struct Scsi_Host *shost,
enum iscsi_host_param param, char *buf);
extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
int dd_data_size, uint16_t qdepth);
int dd_data_size, uint16_t qdepth,
bool xmit_can_sleep);
extern void iscsi_host_remove(struct Scsi_Host *shost);
extern void iscsi_host_free(struct Scsi_Host *shost);
@ -379,6 +383,7 @@ extern void iscsi_session_failure(struct iscsi_cls_session *cls_session,
extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
enum iscsi_param param, char *buf);
extern void iscsi_suspend_tx(struct iscsi_conn *conn);
extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
#define iscsi_conn_printk(prefix, _c, fmt, a...) \
iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \