On Thu, May 27, 2010 at 01:43:00PM -0700, Doug Doan wrote:
> From: Doug Doan <dougd@xxxxxxxx>
>
> When a copy-on-write occurs, we take one of two paths in handle_mm_fault:
> through handle_pte_fault for normal pages, or through hugetlb_fault for
> huge pages.
>
> In the normal page case, we eventually get to do_wp_page and call mmu
> notifiers via ptep_clear_flush_notify. There is no callout to the mmmu
> notifiers in the huge page case. This patch fixes that.
>
> Signed-off-by: Doug Doan <dougd@xxxxxxxx>
> ---
> --- mm/hugetlb.c.orig 2010-05-27 13:07:58.569546314 -0700
> +++ mm/hugetlb.c 2010-05-26 14:41:06.449296524 -0700
> @@ -2345,11 +2345,17 @@ retry_avoidcopy:
> ptep = huge_pte_offset(mm, address & huge_page_mask(h));
> if (likely(pte_same(huge_ptep_get(ptep), pte))) {
> /* Break COW */
> + mmu_notifier_invalidate_range_start(mm,
> + address & huge_page_mask(h),
> + (address & huge_page_mask(h)) + huge_page_size(h));
Should the address not already be aligned?
Otherwise, I don't see any problem.
> huge_ptep_clear_flush(vma, address, ptep);
> set_huge_pte_at(mm, address, ptep,
> make_huge_pte(vma, new_page, 1));
> /* Make the old page be freed below */
> new_page = old_page;
> + mmu_notifier_invalidate_range_end(mm,
> + address & huge_page_mask(h),
> + (address & huge_page_mask(h)) + huge_page_size(h));
> }
> page_cache_release(new_page);
> page_cache_release(old_page);
--
Mel Gorman
Part-time Phd Student Linux Technology Center
University of Limerick IBM Dublin Software Lab
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxxx For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>