[SCSI] add queue_depth ramp up code

Current FC HBA queue_depth ramp up code depends on last queue full time. 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 full value and then updates its only current usages in scsi_track_queue_full to ignore last four bits to keep current usages same while also use this field in added ramp up code. 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. The ramp up is skipped in case the change_queue_depth is not supported by LLD or already reached to added max_queue_depth. Updates added max_queue_depth on every new update to default queue_depth value. The ramp up is also skipped if lapsed time since either last queue ramp up or down is less than LLD specified queue_ramp_up_period. Adds queue_ramp_up_period to sysfs but only if change_queue_depth is supported since ramp up and queue_ramp_up_period is needed only in case change_queue_depth is supported first. Initializes queue_ramp_up_period to 120HZ jiffies as initial default value, it is same as used in existing lpfc and qla2xxx. -v2 Combined all ramp code into this single patch. -v3 Moves max_queue_depth initialization after slave_configure is called from after slave_alloc calling done. Also adjusted max_queue_depth check to skip ramp up if current queue_depth is >= max_queue_depth. -v4 Changes sdev->queue_ramp_up_period unit to ms when using sysfs i/f to store or show its value. Signed-off-by: Vasu Dev <vasu.dev@intel.com> Tested-by: Christof Schmitt <christof.schmitt@de.ibm.com> Tested-by: Giridhar Malavali <giridhar.malavali@qlogic.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>

[SCSI] add queue_depth ramp up code
Current FC HBA queue_depth ramp up code depends on last queue full time. 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 full value and then updates its only current usages in scsi_track_queue_full to ignore last four bits to keep current usages same while also use this field in added ramp up code. 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. The ramp up is skipped in case the change_queue_depth is not supported by LLD or already reached to added max_queue_depth. Updates added max_queue_depth on every new update to default queue_depth value. The ramp up is also skipped if lapsed time since either last queue ramp up or down is less than LLD specified queue_ramp_up_period. Adds queue_ramp_up_period to sysfs but only if change_queue_depth is supported since ramp up and queue_ramp_up_period is needed only in case change_queue_depth is supported first. Initializes queue_ramp_up_period to 120HZ jiffies as initial default value, it is same as used in existing lpfc and qla2xxx. -v2 Combined all ramp code into this single patch. -v3 Moves max_queue_depth initialization after slave_configure is called from after slave_alloc calling done. Also adjusted max_queue_depth check to skip ramp up if current queue_depth is >= max_queue_depth. -v4 Changes sdev->queue_ramp_up_period unit to ms when using sysfs i/f to store or show its value. Signed-off-by: Vasu Dev <vasu.dev@intel.com> Tested-by: Christof Schmitt <christof.schmitt@de.ibm.com> Tested-by: Giridhar Malavali <giridhar.malavali@qlogic.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Vasu Dev · James Bottomley
1 parent 14caf44c69
Showing 5 changed files with 94 additions and 7 deletions Side-by-side Diff
drivers/scsi/scsi.c
drivers/scsi/scsi_error.c
drivers/scsi/scsi_scan.c
drivers/scsi/scsi_sysfs.c
include/scsi/scsi_device.h
@@ -940,10 +940,16 @@
  */
 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;
@@ -331,6 +331,42 @@
 	}
 }
  
+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 ||
+	    sdev->queue_depth >= sdev->max_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 ||
+		    tmp_sdev->queue_depth == sdev->max_queue_depth)
+			continue;
+		/*
+		 * call back into LLD to increase queue_depth by one
+		 * with ramp up reason code.
+		 */
+		sht->change_queue_depth(tmp_sdev, tmp_sdev->queue_depth + 1,
+					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;
@@ -393,6 +429,7 @@
 	 */
 	switch (status_byte(scmd->result)) {
 	case GOOD:
+		scsi_handle_queue_ramp_up(scmd->device);
 	case COMMAND_TERMINATED:
 		return SUCCESS;
 	case CHECK_CONDITION:
@@ -1425,6 +1462,7 @@
 		 */
 		return ADD_TO_MLQUEUE;
 	case GOOD:
+		scsi_handle_queue_ramp_up(scmd->device);
 	case COMMAND_TERMINATED:
 		return SUCCESS;
 	case TASK_ABORTED:
@@ -251,6 +251,7 @@
 	sdev->model = scsi_null_device_strs;
 	sdev->rev = scsi_null_device_strs;
 	sdev->host = shost;
+	sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD;
 	sdev->id = starget->id;
 	sdev->lun = lun;
 	sdev->channel = starget->channel;
@@ -940,6 +941,8 @@
 			return SCSI_SCAN_NO_RESPONSE;
 		}
 	}
+
+	sdev->max_queue_depth = sdev->queue_depth;
  
 	/*
 	 * Ok, the device is now all set up, we can
@@ -771,6 +771,8 @@
 	if (retval < 0)
 		return retval;
  
+	sdev->max_queue_depth = sdev->queue_depth;
+
 	return count;
 }
  
@@ -779,6 +781,37 @@
 	       sdev_store_queue_depth_rw);
  
 static ssize_t
+sdev_show_queue_ramp_up_period(struct device *dev,
+			       struct device_attribute *attr,
+			       char *buf)
+{
+	struct scsi_device *sdev;
+	sdev = to_scsi_device(dev);
+	return snprintf(buf, 20, "%u\n",
+			jiffies_to_msecs(sdev->queue_ramp_up_period));
+}
+
+static ssize_t
+sdev_store_queue_ramp_up_period(struct device *dev,
+				struct device_attribute *attr,
+				const char *buf, size_t count)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	unsigned long period;
+
+	if (strict_strtoul(buf, 10, &period))
+		return -EINVAL;
+
+	sdev->queue_ramp_up_period = msecs_to_jiffies(period);
+	return period;
+}
+
+static struct device_attribute sdev_attr_queue_ramp_up_period =
+	__ATTR(queue_ramp_up_period, S_IRUGO | S_IWUSR,
+	       sdev_show_queue_ramp_up_period,
+	       sdev_store_queue_ramp_up_period);
+
+static ssize_t
 sdev_store_queue_type_rw(struct device *dev, struct device_attribute *attr,
 			 const char *buf, size_t count)
 {
@@ -866,8 +899,12 @@
 	}
  
 	/* create queue files, which may be writable, depending on the host */
-	if (sdev->host->hostt->change_queue_depth)
-		error = device_create_file(&sdev->sdev_gendev, &sdev_attr_queue_depth_rw);
+	if (sdev->host->hostt->change_queue_depth) {
+		error = device_create_file(&sdev->sdev_gendev,
+					   &sdev_attr_queue_depth_rw);
+		error = device_create_file(&sdev->sdev_gendev,
+					   &sdev_attr_queue_ramp_up_period);
+	}
 	else
 		error = device_create_file(&sdev->sdev_gendev, &dev_attr_queue_depth);
 	if (error) {
@@ -81,11 +81,14 @@
 	struct list_head starved_entry;
 	struct scsi_cmnd *current_cmnd;	/* currently active command */
 	unsigned short queue_depth;	/* How deep of a queue we want */
+	unsigned short max_queue_depth;	/* max queue depth */
 	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 */
+#define SCSI_DEFAULT_RAMP_UP_PERIOD	(120 * HZ)
+
+	unsigned long last_queue_ramp_up;	/* last queue ramp up time */
  
 	unsigned int id, lun, channel;
...	...	@@ -940,10 +940,16 @@
940	940	*/
941	941	int scsi_track_queue_full(struct scsi_device *sdev, int depth)
942	942	{
943		- if ((jiffies >> 4) == sdev->last_queue_full_time)
	943	+
	944	+ /*
	945	+ * Don't let QUEUE_FULLs on the same
	946	+ * jiffies count, they could all be from
	947	+ * same event.
	948	+ */
	949	+ if ((jiffies >> 4) == (sdev->last_queue_full_time >> 4))
944	950	return 0;
945	951
946		- sdev->last_queue_full_time = (jiffies >> 4);
	952	+ sdev->last_queue_full_time = jiffies;
947	953	if (sdev->last_queue_full_depth != depth) {
948	954	sdev->last_queue_full_count = 1;
949	955	sdev->last_queue_full_depth = depth;
...	...	@@ -331,6 +331,42 @@
331	331	}
332	332	}
333	333
	334	+static void scsi_handle_queue_ramp_up(struct scsi_device *sdev)
	335	+{
	336	+ struct scsi_host_template *sht = sdev->host->hostt;
	337	+ struct scsi_device *tmp_sdev;
	338	+
	339	+ if (!sht->change_queue_depth \|\|
	340	+ sdev->queue_depth >= sdev->max_queue_depth)
	341	+ return;
	342	+
	343	+ if (time_before(jiffies,
	344	+ sdev->last_queue_ramp_up + sdev->queue_ramp_up_period))
	345	+ return;
	346	+
	347	+ if (time_before(jiffies,
	348	+ sdev->last_queue_full_time + sdev->queue_ramp_up_period))
	349	+ return;
	350	+
	351	+ /*
	352	+ * Walk all devices of a target and do
	353	+ * ramp up on them.
	354	+ */
	355	+ shost_for_each_device(tmp_sdev, sdev->host) {
	356	+ if (tmp_sdev->channel != sdev->channel \|\|
	357	+ tmp_sdev->id != sdev->id \|\|
	358	+ tmp_sdev->queue_depth == sdev->max_queue_depth)
	359	+ continue;
	360	+ /*
	361	+ * call back into LLD to increase queue_depth by one
	362	+ * with ramp up reason code.
	363	+ */
	364	+ sht->change_queue_depth(tmp_sdev, tmp_sdev->queue_depth + 1,
	365	+ SCSI_QDEPTH_RAMP_UP);
	366	+ sdev->last_queue_ramp_up = jiffies;
	367	+ }
	368	+}
	369	+
334	370	static void scsi_handle_queue_full(struct scsi_device *sdev)
335	371	{
336	372	struct scsi_host_template *sht = sdev->host->hostt;
...	...	@@ -393,6 +429,7 @@
393	429	*/
394	430	switch (status_byte(scmd->result)) {
395	431	case GOOD:
	432	+ scsi_handle_queue_ramp_up(scmd->device);
396	433	case COMMAND_TERMINATED:
397	434	return SUCCESS;
398	435	case CHECK_CONDITION:
...	...	@@ -1425,6 +1462,7 @@
1425	1462	*/
1426	1463	return ADD_TO_MLQUEUE;
1427	1464	case GOOD:
	1465	+ scsi_handle_queue_ramp_up(scmd->device);
1428	1466	case COMMAND_TERMINATED:
1429	1467	return SUCCESS;
1430	1468	case TASK_ABORTED:
...	...	@@ -251,6 +251,7 @@
251	251	sdev->model = scsi_null_device_strs;
252	252	sdev->rev = scsi_null_device_strs;
253	253	sdev->host = shost;
	254	+ sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD;
254	255	sdev->id = starget->id;
255	256	sdev->lun = lun;
256	257	sdev->channel = starget->channel;
...	...	@@ -940,6 +941,8 @@
940	941	return SCSI_SCAN_NO_RESPONSE;
941	942	}
942	943	}
	944	+
	945	+ sdev->max_queue_depth = sdev->queue_depth;
943	946
944	947	/*
945	948	* Ok, the device is now all set up, we can
...	...	@@ -771,6 +771,8 @@
771	771	if (retval < 0)
772	772	return retval;
773	773
	774	+ sdev->max_queue_depth = sdev->queue_depth;
	775	+
774	776	return count;
775	777	}
776	778
...	...	@@ -779,6 +781,37 @@
779	781	sdev_store_queue_depth_rw);
780	782
781	783	static ssize_t
	784	+sdev_show_queue_ramp_up_period(struct device *dev,
	785	+ struct device_attribute *attr,
	786	+ char *buf)
	787	+{
	788	+ struct scsi_device *sdev;
	789	+ sdev = to_scsi_device(dev);
	790	+ return snprintf(buf, 20, "%u\n",
	791	+ jiffies_to_msecs(sdev->queue_ramp_up_period));
	792	+}
	793	+
	794	+static ssize_t
	795	+sdev_store_queue_ramp_up_period(struct device *dev,
	796	+ struct device_attribute *attr,
	797	+ const char *buf, size_t count)
	798	+{
	799	+ struct scsi_device *sdev = to_scsi_device(dev);
	800	+ unsigned long period;
	801	+
	802	+ if (strict_strtoul(buf, 10, &period))
	803	+ return -EINVAL;
	804	+
	805	+ sdev->queue_ramp_up_period = msecs_to_jiffies(period);
	806	+ return period;
	807	+}
	808	+
	809	+static struct device_attribute sdev_attr_queue_ramp_up_period =
	810	+ __ATTR(queue_ramp_up_period, S_IRUGO \| S_IWUSR,
	811	+ sdev_show_queue_ramp_up_period,
	812	+ sdev_store_queue_ramp_up_period);
	813	+
	814	+static ssize_t
782	815	sdev_store_queue_type_rw(struct device dev, struct device_attribute attr,
783	816	const char *buf, size_t count)
784	817	{
...	...	@@ -866,8 +899,12 @@
866	899	}
867	900
868	901	/* create queue files, which may be writable, depending on the host */
869		- if (sdev->host->hostt->change_queue_depth)
870		- error = device_create_file(&sdev->sdev_gendev, &sdev_attr_queue_depth_rw);
	902	+ if (sdev->host->hostt->change_queue_depth) {
	903	+ error = device_create_file(&sdev->sdev_gendev,
	904	+ &sdev_attr_queue_depth_rw);
	905	+ error = device_create_file(&sdev->sdev_gendev,
	906	+ &sdev_attr_queue_ramp_up_period);
	907	+ }
871	908	else
872	909	error = device_create_file(&sdev->sdev_gendev, &dev_attr_queue_depth);
873	910	if (error) {
...	...	@@ -81,11 +81,14 @@
81	81	struct list_head starved_entry;
82	82	struct scsi_cmnd current_cmnd; / currently active command */
83	83	unsigned short queue_depth; /* How deep of a queue we want */
	84	+ unsigned short max_queue_depth; /* max queue depth */
84	85	unsigned short last_queue_full_depth; /* These two are used by */
85	86	unsigned short last_queue_full_count; /* scsi_track_queue_full() */
86		- unsigned long last_queue_full_time;/* don't let QUEUE_FULLs on the same
87		- jiffie count on our counter, they
88		- could all be from the same event. */
	87	+ unsigned long last_queue_full_time; /* last queue full time */
	88	+ unsigned long queue_ramp_up_period; /* ramp up period in jiffies */
	89	+#define SCSI_DEFAULT_RAMP_UP_PERIOD (120 * HZ)
	90	+
	91	+ unsigned long last_queue_ramp_up; /* last queue ramp up time */
89	92
90	93	unsigned int id, lun, channel;
91	94