Re: [patch] cache pipe buf page address for non-highmem arch

Ken Chen
2007-03-24T01:01:57Z

On 3/23/07, Christoph Hellwig <hch@infradead.org> wrote:
> I think you're fixing the symptom here and not the cause. If calculating
> the virtual address of a page is so expensive on your setup it should
> define WANT_PAGE_VIRTUAL and we should always cache the virtual address
> in struct page. There's a lot more code, epecially in filesystems that's
> rather upset about a slow page_address.

Adding WANT_PAGE_VIRTUAL would be too costly I think as it will expand
the sizeof struct page. I would rather go incremental fix on these
issues and not blindly increase page struct size.