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Diffstat (limited to 'drivers/s390/scsi/zfcp_qdio.c')
-rw-r--r--drivers/s390/scsi/zfcp_qdio.c68
1 files changed, 56 insertions, 12 deletions
diff --git a/drivers/s390/scsi/zfcp_qdio.c b/drivers/s390/scsi/zfcp_qdio.c
index 23ab16d65f2a..16a332d501e7 100644
--- a/drivers/s390/scsi/zfcp_qdio.c
+++ b/drivers/s390/scsi/zfcp_qdio.c
@@ -20,6 +20,9 @@ static bool enable_multibuffer = true;
module_param_named(datarouter, enable_multibuffer, bool, 0400);
MODULE_PARM_DESC(datarouter, "Enable hardware data router support (default on)");
+#define ZFCP_QDIO_REQUEST_RESCAN_MSECS (MSEC_PER_SEC * 10)
+#define ZFCP_QDIO_REQUEST_SCAN_MSECS MSEC_PER_SEC
+
static void zfcp_qdio_handler_error(struct zfcp_qdio *qdio, char *dbftag,
unsigned int qdio_err)
{
@@ -70,15 +73,41 @@ static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err,
zfcp_qdio_handler_error(qdio, "qdireq1", qdio_err);
return;
}
+}
- /* cleanup all SBALs being program-owned now */
- zfcp_qdio_zero_sbals(qdio->req_q, idx, count);
+static void zfcp_qdio_request_tasklet(struct tasklet_struct *tasklet)
+{
+ struct zfcp_qdio *qdio = from_tasklet(qdio, tasklet, request_tasklet);
+ struct ccw_device *cdev = qdio->adapter->ccw_device;
+ unsigned int start, error;
+ int completed;
- spin_lock_irq(&qdio->stat_lock);
- zfcp_qdio_account(qdio);
- spin_unlock_irq(&qdio->stat_lock);
- atomic_add(count, &qdio->req_q_free);
- wake_up(&qdio->req_q_wq);
+ completed = qdio_inspect_queue(cdev, 0, false, &start, &error);
+ if (completed > 0) {
+ if (error) {
+ zfcp_qdio_handler_error(qdio, "qdreqt1", error);
+ } else {
+ /* cleanup all SBALs being program-owned now */
+ zfcp_qdio_zero_sbals(qdio->req_q, start, completed);
+
+ spin_lock_irq(&qdio->stat_lock);
+ zfcp_qdio_account(qdio);
+ spin_unlock_irq(&qdio->stat_lock);
+ atomic_add(completed, &qdio->req_q_free);
+ wake_up(&qdio->req_q_wq);
+ }
+ }
+
+ if (atomic_read(&qdio->req_q_free) < QDIO_MAX_BUFFERS_PER_Q)
+ timer_reduce(&qdio->request_timer,
+ jiffies + msecs_to_jiffies(ZFCP_QDIO_REQUEST_RESCAN_MSECS));
+}
+
+static void zfcp_qdio_request_timer(struct timer_list *timer)
+{
+ struct zfcp_qdio *qdio = from_timer(qdio, timer, request_timer);
+
+ tasklet_schedule(&qdio->request_tasklet);
}
static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err,
@@ -139,8 +168,11 @@ static void zfcp_qdio_irq_tasklet(struct tasklet_struct *tasklet)
unsigned int start, error;
int completed;
- /* Check the Response Queue, and kick off the Request Queue tasklet: */
- completed = qdio_get_next_buffers(cdev, 0, &start, &error);
+ if (atomic_read(&qdio->req_q_free) < QDIO_MAX_BUFFERS_PER_Q)
+ tasklet_schedule(&qdio->request_tasklet);
+
+ /* Check the Response Queue: */
+ completed = qdio_inspect_queue(cdev, 0, true, &start, &error);
if (completed < 0)
return;
if (completed > 0)
@@ -286,7 +318,7 @@ int zfcp_qdio_send(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
/*
* This should actually be a spin_lock_bh(stat_lock), to protect against
- * zfcp_qdio_int_req() in tasklet context.
+ * Request Queue completion processing in tasklet context.
* But we can't do so (and are safe), as we always get called with IRQs
* disabled by spin_lock_irq[save](req_q_lock).
*/
@@ -308,6 +340,12 @@ int zfcp_qdio_send(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
return retval;
}
+ if (atomic_read(&qdio->req_q_free) <= 2 * ZFCP_QDIO_MAX_SBALS_PER_REQ)
+ tasklet_schedule(&qdio->request_tasklet);
+ else
+ timer_reduce(&qdio->request_timer,
+ jiffies + msecs_to_jiffies(ZFCP_QDIO_REQUEST_SCAN_MSECS));
+
/* account for transferred buffers */
qdio->req_q_idx += sbal_number;
qdio->req_q_idx %= QDIO_MAX_BUFFERS_PER_Q;
@@ -368,6 +406,8 @@ void zfcp_qdio_close(struct zfcp_qdio *qdio)
wake_up(&qdio->req_q_wq);
tasklet_disable(&qdio->irq_tasklet);
+ tasklet_disable(&qdio->request_tasklet);
+ del_timer_sync(&qdio->request_timer);
qdio_stop_irq(adapter->ccw_device);
qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR);
@@ -428,8 +468,6 @@ int zfcp_qdio_open(struct zfcp_qdio *qdio)
init_data.int_parm = (unsigned long) qdio;
init_data.input_sbal_addr_array = input_sbals;
init_data.output_sbal_addr_array = output_sbals;
- init_data.scan_threshold =
- QDIO_MAX_BUFFERS_PER_Q - ZFCP_QDIO_MAX_SBALS_PER_REQ * 2;
if (qdio_establish(cdev, &init_data))
goto failed_establish;
@@ -471,6 +509,8 @@ int zfcp_qdio_open(struct zfcp_qdio *qdio)
atomic_set(&qdio->req_q_free, QDIO_MAX_BUFFERS_PER_Q);
atomic_or(ZFCP_STATUS_ADAPTER_QDIOUP, &qdio->adapter->status);
+ /* Enable processing for Request Queue completions: */
+ tasklet_enable(&qdio->request_tasklet);
/* Enable processing for QDIO interrupts: */
tasklet_enable(&qdio->irq_tasklet);
/* This results in a qdio_start_irq(): */
@@ -494,6 +534,7 @@ void zfcp_qdio_destroy(struct zfcp_qdio *qdio)
return;
tasklet_kill(&qdio->irq_tasklet);
+ tasklet_kill(&qdio->request_tasklet);
if (qdio->adapter->ccw_device)
qdio_free(qdio->adapter->ccw_device);
@@ -520,8 +561,11 @@ int zfcp_qdio_setup(struct zfcp_adapter *adapter)
spin_lock_init(&qdio->req_q_lock);
spin_lock_init(&qdio->stat_lock);
+ timer_setup(&qdio->request_timer, zfcp_qdio_request_timer, 0);
tasklet_setup(&qdio->irq_tasklet, zfcp_qdio_irq_tasklet);
+ tasklet_setup(&qdio->request_tasklet, zfcp_qdio_request_tasklet);
tasklet_disable(&qdio->irq_tasklet);
+ tasklet_disable(&qdio->request_tasklet);
adapter->qdio = qdio;
return 0;