On 09/03/2009 05:23 PM, Vasu Dev wrote:
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 | 36 ++++++++++++++++++++++++++++++++++++
1 files changed, 36 insertions(+), 0 deletions(-)
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index 7d1b862..c820ee7 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -331,6 +331,40 @@ 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;
I just noticed that while on the ramp down we just check the id, but why
on the ramp up do we check the channel and id?
Do we just want to adjust the devices on one specific target? If so is
starget_for_each_device() better to use?
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
