Re: [RFC PATCH] s390: mm: rmap: Transfer storage key to struct page under the page lock

Rik van Riel
2012-04-16T14:53:07Z

On 04/16/2012 10:14 AM, Mel Gorman wrote:
> This patch is horribly ugly and there has to be a better way of doing
> it. I'm looking for suggestions on what s390 can do here that is not
> painful or broken.

I'm hoping the S390 arch maintainers have an idea.

Ugly or not, we'll need something to fix the bug.

> + * When the late PTE has gone, s390 must transfer the dirty flag from the
> + * storage key to struct page. We can usually skip this if the page is anon,
> + * so about to be freed; but perhaps not if it's in swapcache - there might
> + * be another pte slot containing the swap entry, but page not yet written to
> + * swap.
> *
> - * The caller needs to hold the pte lock.
> + * set_page_dirty() is called while the page_mapcount is still postive and
> + * under the page lock to avoid races with the mapping being invalidated.
> */
> -void page_remove_rmap(struct page *page)
> +static void propogate_storage_key(struct page *page, bool lock_required)

Do you mean "propAgate" ?

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