Current FC HBA queue_depth ramp up code depends on :-
1. last queue full time.
2. last queue ramp up time.
3. ramp up period (time interval)
The sdev already has last_queue_full_time field to track last
queue full time but stored value is truncated by last four bits.
So this patch updates last_queue_full_time without truncating
last 4 bits to store complete value and then updates its only
current usages in scsi_track_queue_full to ignore last four bits
to keep current usages same. This will allow same
last_queue_full_time used by scsi_track_queue_full and queue_depth
ramp up code.
Adds additional new sdev fields for above 2 and 3 items.
Signed-off-by: Vasu Dev <vasu.dev@xxxxxxxxx>
---
drivers/scsi/scsi.c | 10 ++++++++--
include/scsi/scsi_device.h | 6 +++---
2 files changed, 11 insertions(+), 5 deletions(-)
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index b6e0307..bffaa9c 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -937,10 +937,16 @@ EXPORT_SYMBOL(scsi_adjust_queue_depth);
*/
int scsi_track_queue_full(struct scsi_device *sdev, int depth)
{
- if ((jiffies >> 4) == sdev->last_queue_full_time)
+
+ /*
+ * Don't let QUEUE_FULLs on the same
+ * jiffies count, they could all be from
+ * same event.
+ */
+ if ((jiffies >> 4) == (sdev->last_queue_full_time >> 4))
return 0;
- sdev->last_queue_full_time = (jiffies >> 4);
+ sdev->last_queue_full_time = jiffies;
if (sdev->last_queue_full_depth != depth) {
sdev->last_queue_full_count = 1;
sdev->last_queue_full_depth = depth;
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 9af48cb..041d4f9 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -83,9 +83,9 @@ struct scsi_device {
unsigned short queue_depth; /* How deep of a queue we want */
unsigned short last_queue_full_depth; /* These two are used by */
unsigned short last_queue_full_count; /* scsi_track_queue_full() */
- unsigned long last_queue_full_time;/* don't let QUEUE_FULLs on the same
- jiffie count on our counter, they
- could all be from the same event. */
+ unsigned long last_queue_full_time; /* last queue full time */
+ unsigned long queue_ramp_up_period; /* ramp up period in jiffies */
+ unsigned long last_queue_ramp_up; /* last queue ramp up time */
unsigned int id, lun, channel;
--
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