diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
index 0fedca6e273b..590997961a93 100644
--- a/drivers/scsi/ipr.c
+++ b/drivers/scsi/ipr.c
@@ -850,8 +850,6 @@ static void ipr_do_req(struct ipr_cmnd *ipr_cmd,
 
 	ipr_trc_hook(ipr_cmd, IPR_TRACE_START, 0);
 
-	mb();
-
 	ipr_send_command(ipr_cmd);
 }
 
@@ -985,8 +983,6 @@ static void ipr_send_hcam(struct ipr_ioa_cfg *ioa_cfg, u8 type,
 
 		ipr_trc_hook(ipr_cmd, IPR_TRACE_START, IPR_IOA_RES_ADDR);
 
-		mb();
-
 		ipr_send_command(ipr_cmd);
 	} else {
 		list_add_tail(&hostrcb->queue, &ioa_cfg->hostrcb_free_q);
@@ -5863,14 +5859,12 @@ static int ipr_queuecommand_lck(struct scsi_cmnd *scsi_cmd,
 			rc = ipr_build_ioadl(ioa_cfg, ipr_cmd);
 	}
 
-	if (likely(rc == 0)) {
-		mb();
-		ipr_send_command(ipr_cmd);
-	} else {
-		 list_move_tail(&ipr_cmd->queue, &ioa_cfg->free_q);
-		 return SCSI_MLQUEUE_HOST_BUSY;
+	if (unlikely(rc != 0)) {
+		list_move_tail(&ipr_cmd->queue, &ioa_cfg->free_q);
+		return SCSI_MLQUEUE_HOST_BUSY;
 	}
 
+	ipr_send_command(ipr_cmd);
 	return 0;
 }
 
@@ -6248,8 +6242,6 @@ static unsigned int ipr_qc_issue(struct ata_queued_cmd *qc)
 		return AC_ERR_INVALID;
 	}
 
-	mb();
-
 	ipr_send_command(ipr_cmd);
 
 	return 0;