On Tue, 2008-02-26 at 16:29 +0100, Miklos Szeredi wrote: > > > mm-page_file_methods.patch > > > > > > This makes page_offset and others more expensive by adding a > > > conditional jump to a function call that is not usually made. > > > > > > Why do swap pages have a different index to everyone else? > > > > Because the page->index of an anonymous page is related to its (anon)vma > > so that it satisfies the constraints for vm_normal_page(). > > > > The index in the swap file it totally unrelated and quite random. Hence > > the swap-cache uses page->private to store it in. > > Yeah, and putting the condition into page_offset() will confuse code > which uses it for finding the offset in the VMA
Right, do we do that anywhere? > or in a tmpfs file. Good point. I really should go read tmpfs some day, its really a blind spot for me. > So why not just have a separate page_swap_offset() function, used > exclusively by swap_in/out()? That would require duplicating quite a lot of NFS code from what I can see. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
