[SCSI] lpfc 8.3.33: Misc changes to optimize critical path

Signed-off-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

1 files changed, 13 insertions, 8 deletions

diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index 51c7fc746de1..d7afd0fb4579 100644
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -94,6 +94,7 @@ lpfc_sli4_wq_put(struct lpfc_queue *q, union lpfc_wqe *wqe)
         union lpfc_wqe *temp_wqe;
         struct lpfc_register doorbell;
         uint32_t host_index;
+        uint32_t idx;
 
         /* sanity check on queue memory */
         if (unlikely(!q))
@@ -101,7 +102,8 @@ lpfc_sli4_wq_put(struct lpfc_queue *q, union lpfc_wqe *wqe)
         temp_wqe = q->qe[q->host_index].wqe;
 
         /* If the host has not yet processed the next entry then we are done */
-        if (((q->host_index + 1) % q->entry_count) == q->hba_index) {
+        idx = ((q->host_index + 1) % q->entry_count);
+        if (idx == q->hba_index) {
                 q->WQ_overflow++;
                 return -ENOMEM;
         }
@@ -115,7 +117,8 @@ lpfc_sli4_wq_put(struct lpfc_queue *q, union lpfc_wqe *wqe)
 
         /* Update the host index before invoking device */
         host_index = q->host_index;
-        q->host_index = ((q->host_index + 1) % q->entry_count);
+
+        q->host_index = idx;
 
         /* Ring Doorbell */
         doorbell.word0 = 0;
@@ -123,7 +126,6 @@ lpfc_sli4_wq_put(struct lpfc_queue *q, union lpfc_wqe *wqe)
         bf_set(lpfc_wq_doorbell_index, &doorbell, host_index);
         bf_set(lpfc_wq_doorbell_id, &doorbell, q->queue_id);
         writel(doorbell.word0, q->phba->sli4_hba.WQDBregaddr);
-        readl(q->phba->sli4_hba.WQDBregaddr); /* Flush */
 
         return 0;
 }
@@ -197,7 +199,6 @@ lpfc_sli4_mq_put(struct lpfc_queue *q, struct lpfc_mqe *mqe)
         bf_set(lpfc_mq_doorbell_num_posted, &doorbell, 1);
         bf_set(lpfc_mq_doorbell_id, &doorbell, q->queue_id);
         writel(doorbell.word0, q->phba->sli4_hba.MQDBregaddr);
-        readl(q->phba->sli4_hba.MQDBregaddr); /* Flush */
         return 0;
 }
 
@@ -237,6 +238,7 @@ static struct lpfc_eqe *
 lpfc_sli4_eq_get(struct lpfc_queue *q)
 {
         struct lpfc_eqe *eqe;
+        uint32_t idx;
 
         /* sanity check on queue memory */
         if (unlikely(!q))
@@ -247,10 +249,11 @@ lpfc_sli4_eq_get(struct lpfc_queue *q)
         if (!bf_get_le32(lpfc_eqe_valid, eqe))
                 return NULL;
         /* If the host has not yet processed the next entry then we are done */
-        if (((q->hba_index + 1) % q->entry_count) == q->host_index)
+        idx = ((q->hba_index + 1) % q->entry_count);
+        if (idx == q->host_index)
                 return NULL;
 
-        q->hba_index = ((q->hba_index + 1) % q->entry_count);
+        q->hba_index = idx;
         return eqe;
 }
 
@@ -321,6 +324,7 @@ static struct lpfc_cqe *
 lpfc_sli4_cq_get(struct lpfc_queue *q)
 {
         struct lpfc_cqe *cqe;
+        uint32_t idx;
 
         /* sanity check on queue memory */
         if (unlikely(!q))
@@ -330,11 +334,12 @@ lpfc_sli4_cq_get(struct lpfc_queue *q)
         if (!bf_get_le32(lpfc_cqe_valid, q->qe[q->hba_index].cqe))
                 return NULL;
         /* If the host has not yet processed the next entry then we are done */
-        if (((q->hba_index + 1) % q->entry_count) == q->host_index)
+        idx = ((q->hba_index + 1) % q->entry_count);
+        if (idx == q->host_index)
                 return NULL;
 
         cqe = q->qe[q->hba_index].cqe;
-        q->hba_index = ((q->hba_index + 1) % q->entry_count);
+        q->hba_index = idx;
         return cqe;
 }