1402 ixgbe intel 10gbit driver very slow (backs out 534)

*** 7330,7357 ****
                  fp = waitfp;
          *handlep = impl_acc_hdl_alloc(fp, arg);
          if (*handlep == NULL)
                  return (DDI_FAILURE);
  
- /* SPARC mappings are always cacheable, as SPARC guarantees cache coherency. */
- #ifndef __sparc
-         /* Transform attributes into correct cache flags. */
-         if ((flags & IOMEM_DATA_MASK) == 0) {
-                 switch (accattrp->devacc_attr_dataorder) {
-                 case DDI_STRICTORDER_ACC:
-                         flags |= IOMEM_DATA_UNCACHED;
-                         break;
-                 case DDI_MERGING_OK_ACC:
-                         flags |= IOMEM_DATA_UC_WR_COMBINE;
-                         break;
-                 default:
-                         flags |= IOMEM_DATA_CACHED;
-                         break;
-                 }
-         }
- #endif
- 
          /* check if the cache attributes are supported */
          if (i_ddi_check_cache_attr(flags) == B_FALSE)
                  return (DDI_FAILURE);
  
          /*
--- 7330,7339 ----