MFprojects/camlock r248890, r248897, r248898, r248900, r248903, r248905,

r248917, r248918, r248978, r249001, r249014, r249030:

Remove multilevel freezing mechanism, implemented to handle specifics of
the ATA/SATA error recovery, when post-reset recovery commands should be
allocated when queues are already full of payload requests.  Instead of
removing frozen CCBs with specified range of priorities from the queue
to provide free openings, use simple hack, allowing explicit CCBs over-
allocation for requests with priority higher (numerically lower) then
CAM_PRIORITY_OOB threshold.

Simplify CCB allocation logic by removing SIM-level allocation queue.
After that SIM-level queue manages only CCBs execution, while allocation
logic is localized within each single device.

Suggested by:	gibbs

1 files changed, 5 insertions, 86 deletions

diff --git a/sys/cam/cam_queue.h b/sys/cam/cam_queue.h
index dd9f9a7..a000fe4 100644
--- a/sys/cam/cam_queue.h
+++ b/sys/cam/cam_queue.h
@@ -48,7 +48,7 @@ struct camq {
 	int	   array_size;
 	int	   entries;
 	u_int32_t  generation;
-	u_int32_t  qfrozen_cnt[CAM_RL_VALUES];
+	u_int32_t  qfrozen_cnt;
 };
 
 TAILQ_HEAD(ccb_hdr_tailq, ccb_hdr);
@@ -58,7 +58,8 @@ SLIST_HEAD(ccb_hdr_slist, ccb_hdr);
 struct cam_ccbq {
 	struct	camq queue;
 	int	devq_openings;
-	int	dev_openings;	
+	int	devq_allocating;
+	int	dev_openings;
 	int	dev_active;
 	int	held;
 };
@@ -66,11 +67,7 @@ struct cam_ccbq {
 struct cam_ed;
 
 struct cam_devq {
-	struct	camq alloc_queue;
 	struct	camq send_queue;
-	struct	cam_ed *active_dev;
-	int	alloc_openings;
-	int	alloc_active;
 	int	send_openings;
 	int	send_active;
 };
@@ -195,8 +192,7 @@ cam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb)
 {
 	ccbq->held--;
 	camq_insert(&ccbq->queue, &new_ccb->ccb_h.pinfo);
-	if (ccbq->queue.qfrozen_cnt[CAM_PRIORITY_TO_RL(
-	    new_ccb->ccb_h.pinfo.priority)] > 0) {
+	if (ccbq->queue.qfrozen_cnt > 0) {
 		ccbq->devq_openings++;
 		ccbq->held++;
 		return (1);
@@ -208,8 +204,7 @@ static __inline int
 cam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb)
 {
 	camq_remove(&ccbq->queue, ccb->ccb_h.pinfo.index);
-	if (ccbq->queue.qfrozen_cnt[CAM_PRIORITY_TO_RL(
-	    ccb->ccb_h.pinfo.priority)] > 0) {
+	if (ccbq->queue.qfrozen_cnt > 0) {
 		ccbq->devq_openings--;
 		ccbq->held--;
 		return (1);
@@ -248,81 +243,5 @@ cam_ccbq_release_opening(struct cam_ccbq *ccbq)
 	ccbq->devq_openings++;
 }
 
-static __inline int
-cam_ccbq_freeze(struct cam_ccbq *ccbq, cam_rl rl, u_int32_t cnt)
-{
-	int i, frozen = 0;
-	cam_rl p, n;
-
-	/* Find pevious run level. */
-	for (p = 0; p < CAM_RL_VALUES && ccbq->queue.qfrozen_cnt[p] == 0; p++);
-	/* Find new run level. */
-	n = min(rl, p);
-	/* Apply new run level. */
-	for (i = rl; i < CAM_RL_VALUES; i++)
-		ccbq->queue.qfrozen_cnt[i] += cnt;
-	/* Update ccbq statistics. */
-	if (n == p)
-		return (0);
-	for (i = CAMQ_HEAD; i <= ccbq->queue.entries; i++) {
-		cam_rl rrl =
-		    CAM_PRIORITY_TO_RL(ccbq->queue.queue_array[i]->priority);
-		if (rrl < n)
-			continue;
-		if (rrl >= p)
-			break;
-		ccbq->devq_openings++;
-		ccbq->held++;
-		frozen++;
-	}
-	return (frozen);
-}
-
-static __inline int
-cam_ccbq_release(struct cam_ccbq *ccbq, cam_rl rl, u_int32_t cnt)
-{
-	int i, released = 0;
-	cam_rl p, n;
-
-	/* Apply new run level. */
-	for (i = rl; i < CAM_RL_VALUES; i++)
-		ccbq->queue.qfrozen_cnt[i] -= cnt;
-	/* Find new run level. */
-	for (n = 0; n < CAM_RL_VALUES && ccbq->queue.qfrozen_cnt[n] == 0; n++);
-	/* Find previous run level. */
-	p = min(rl, n);
-	/* Update ccbq statistics. */
-	if (n == p)
-		return (0);
-	for (i = CAMQ_HEAD; i <= ccbq->queue.entries; i++) {
-		cam_rl rrl =
-		    CAM_PRIORITY_TO_RL(ccbq->queue.queue_array[i]->priority);
-		if (rrl < p)
-			continue;
-		if (rrl >= n)
-			break;
-		ccbq->devq_openings--;
-		ccbq->held--;
-		released++;
-	}
-	return (released);
-}
-
-static __inline u_int32_t
-cam_ccbq_frozen(struct cam_ccbq *ccbq, cam_rl rl)
-{
-	
-	return (ccbq->queue.qfrozen_cnt[rl]);
-}
-
-static __inline u_int32_t
-cam_ccbq_frozen_top(struct cam_ccbq *ccbq)
-{
-	cam_rl rl;
-	
-	rl = CAM_PRIORITY_TO_RL(CAMQ_GET_PRIO(&ccbq->queue));
-	return (ccbq->queue.qfrozen_cnt[rl]);
-}
-
 #endif /* _KERNEL */
 #endif  /* _CAM_CAM_QUEUE_H */