Adds scsi_handle_queue_ramp_up to ramp up queue_depth on
successful completion of IO. The scsi_handle_queue_ramp_up
will do ramp up on all luns of a target, just same as
ramp down done on all luns on a target.
However ramp up is skipped if lapsed time since either
last queue ramp up or down is less than LLD specified
queue_ramp_up_period.
The ramp up is also skipped in case the change_queue_depth
is not supported by LLD.
Signed-off-by: Vasu Dev <vasu.dev@xxxxxxxxx>
---
drivers/scsi/scsi_error.c | 38 ++++++++++++++++++++++++++++++++++++++
1 files changed, 38 insertions(+), 0 deletions(-)
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 7d1b862..08490c7 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -331,6 +331,42 @@ static int scsi_check_sense(struct scsi_cmnd *scmd)
}
}
+static void scsi_handle_queue_ramp_up(struct scsi_device *sdev)
+{
+ struct scsi_host_template *sht = sdev->host->hostt;
+ struct scsi_device *tmp_sdev;
+
+ if (!sht->change_queue_depth)
+ return;
+
+ if (time_before(jiffies,
+ sdev->last_queue_ramp_up + sdev->queue_ramp_up_period))
+ return;
+
+ if (time_before(jiffies,
+ sdev->last_queue_full_time + sdev->queue_ramp_up_period))
+ return;
+
+ /*
+ * Walk all devices of a target and do
+ * ramp up on them.
+ */
+ shost_for_each_device(tmp_sdev, sdev->host) {
+ if ((tmp_sdev->channel != sdev->channel) ||
+ (tmp_sdev->id != sdev->id))
+ continue;
+ /*
+ * We do not know max queue_depth supported by the
+ * device, so pass the existing queue_depth and let
+ * device adjust the queue_depth on ramp up change
+ * event.
+ */
+ sht->change_queue_depth(tmp_sdev, tmp_sdev->queue_depth,
+ SCSI_QDEPTH_RAMP_UP);
+ sdev->last_queue_ramp_up = jiffies;
+ }
+}
+
static void scsi_handle_queue_full(struct scsi_device *sdev)
{
struct scsi_host_template *sht = sdev->host->hostt;
@@ -392,6 +428,7 @@ static int scsi_eh_completed_normally(struct scsi_cmnd *scmd)
*/
switch (status_byte(scmd->result)) {
case GOOD:
+ scsi_handle_queue_ramp_up(scmd->device);
case COMMAND_TERMINATED:
return SUCCESS;
case CHECK_CONDITION:
@@ -1421,6 +1458,7 @@ int scsi_decide_disposition(struct scsi_cmnd *scmd)
*/
return ADD_TO_MLQUEUE;
case GOOD:
+ scsi_handle_queue_ramp_up(scmd->device);
case COMMAND_TERMINATED:
return SUCCESS;
case TASK_ABORTED:
--
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