cciss: reinstate proper FIFO order of command queue list

Commit 8a3173d inadvertently changed the ordering when
switching to hlists. Change to regular list heads so we
can use tail list adds, this improves performance.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

drivers/block/cciss.c

@@ -266,9 +266,9 @@ static void set_performant_mode(ctlr_info_t *h, CommandList_struct *c)
 /*
  * Enqueuing and dequeuing functions for cmdlists.
  */
-static inline void addQ(struct hlist_head *list, CommandList_struct *c)
+static inline void addQ(struct list_head *list, CommandList_struct *c)
 {
-	hlist_add_head(&c->list, list);
+	list_add_tail(&c->list, list);
 }
 
 static inline void removeQ(CommandList_struct *c)
@@ -281,12 +281,12 @@ static inline void removeQ(CommandList_struct *c)
 	 * them off as 'stale' to prevent the driver from
 	 * falling over.
 	 */
-	if (WARN_ON(hlist_unhashed(&c->list))) {
+	if (WARN_ON(list_empty(&c->list))) {
 		c->cmd_type = CMD_MSG_STALE;
 		return;
 	}
 
-	hlist_del_init(&c->list);
+	list_del_init(&c->list);
 }
 
 static void enqueue_cmd_and_start_io(ctlr_info_t *h,
@@ -935,7 +935,7 @@ static CommandList_struct *cmd_alloc(ctlr_info_t *h)
 
 	c->cmdindex = i;
 
-	INIT_HLIST_NODE(&c->list);
+	INIT_LIST_HEAD(&c->list);
 	c->busaddr = (__u32) cmd_dma_handle;
 	temp64.val = (__u64) err_dma_handle;
 	c->ErrDesc.Addr.lower = temp64.val32.lower;
@@ -974,7 +974,7 @@ static CommandList_struct *cmd_special_alloc(ctlr_info_t *h)
 	}
 	memset(c->err_info, 0, sizeof(ErrorInfo_struct));
 
-	INIT_HLIST_NODE(&c->list);
+	INIT_LIST_HEAD(&c->list);
 	c->busaddr = (__u32) cmd_dma_handle;
 	temp64.val = (__u64) err_dma_handle;
 	c->ErrDesc.Addr.lower = temp64.val32.lower;
@@ -2933,8 +2933,8 @@ static void start_io(ctlr_info_t *h)
 {
 	CommandList_struct *c;
 
-	while (!hlist_empty(&h->reqQ)) {
-		c = hlist_entry(h->reqQ.first, CommandList_struct, list);
+	while (!list_empty(&h->reqQ)) {
+		c = list_entry(h->reqQ.next, CommandList_struct, list);
 		/* can't do anything if fifo is full */
 		if ((h->access.fifo_full(h))) {
 			dev_warn(&h->pdev->dev, "fifo full\n");
@@ -3447,11 +3447,10 @@ static inline u32 process_nonindexed_cmd(ctlr_info_t *h, u32 raw_tag)
 {
 	u32 tag;
 	CommandList_struct *c = NULL;
-	struct hlist_node *tmp;
 	__u32 busaddr_masked, tag_masked;
 
 	tag = cciss_tag_discard_error_bits(raw_tag);
-	hlist_for_each_entry(c, tmp, &h->cmpQ, list) {
+	list_for_each_entry(c, &h->cmpQ, list) {
 		busaddr_masked = cciss_tag_discard_error_bits(c->busaddr);
 		tag_masked = cciss_tag_discard_error_bits(tag);
 		if (busaddr_masked == tag_masked) {
@@ -4632,8 +4631,8 @@ static int __devinit cciss_init_one(struct pci_dev *pdev,
 	h = hba[i];
 	h->pdev = pdev;
 	h->busy_initializing = 1;
-	INIT_HLIST_HEAD(&h->cmpQ);
-	INIT_HLIST_HEAD(&h->reqQ);
+	INIT_LIST_HEAD(&h->cmpQ);
+	INIT_LIST_HEAD(&h->reqQ);
 	mutex_init(&h->busy_shutting_down);
 
 	if (cciss_pci_init(h) != 0)

drivers/block/cciss.h

@@ -103,8 +103,8 @@ struct ctlr_info
 	struct access_method access;
 
 	/* queue and queue Info */ 
-	struct hlist_head reqQ;
-	struct hlist_head cmpQ;
+	struct list_head reqQ;
+	struct list_head cmpQ;
 	unsigned int Qdepth;
 	unsigned int maxQsinceinit;
 	unsigned int maxSG;

drivers/block/cciss_cmd.h

@@ -195,7 +195,7 @@ typedef struct _CommandList_struct {
   int			   ctlr;
   int			   cmd_type; 
   long			   cmdindex;
-  struct hlist_node list;
+  struct list_head list;
   struct request *	   rq;
   struct completion *waiting;
   int	 retry_count;