Messages in this thread Patch in this message | | | From | "Chen, Kenneth W" <> | Subject | RE: [PATCH 1/1] Implement shared page tables | Date | Thu, 1 Sep 2005 21:26:27 -0700 |
| |
Dave McCracken wrote on Tuesday, August 30, 2005 3:13 PM > This patch implements page table sharing for all shared memory regions that > span an entire page table page. It supports sharing at multiple page > levels, depending on the architecture.
In function pt_share_pte():
> + while ((svma = next_shareable_vma(vma, svma, &iter))) { > + spgd = pgd_offset(svma->vm_mm, address); > + if (pgd_none(*spgd)) > + continue; > + > + spud = pud_offset(spgd, address); > + if (pud_none(*spud)) > + continue; > + > + spmd = pmd_offset(spud, address); > + if (pmd_none(*spmd)) > + continue; .... > + page = pmd_page(*spmd); > + pt_increment_share(page); > + pmd_populate(vma->vm_mm, pmd, page); > + }
Do you really have to iterate through all the vma? Can't you just break out of the while loop on first successful match and populating the pmd? I would think you will find them to be the same pte page. Or did I miss some thing?
--- ./mm/ptshare.c.orig 2005-09-01 21:16:35.311915518 -0700 +++ ./mm/ptshare.c 2005-09-01 21:18:24.629296992 -0700 @@ -200,6 +200,7 @@ pt_share_pte(struct vm_area_struct *vma, page = pmd_page(*spmd); pt_increment_share(page); pmd_populate(vma->vm_mm, pmd, page); + break; } } pte = pte_alloc_map(vma->vm_mm, pmd, address);
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |