Re: [patch] NEW: arca-vm-21, swapout via shrink_mmap using PG_dirty

Linus Torvalds
1999-01-18T17:51:15Z

On Mon, 18 Jan 1999, Andrea Arcangeli wrote:
>
> I can't understand this. I think to know _where_ to mark the page dirty
> (in the `if (vm_op->swapout)' path) but I don't understand _where_ to
> write the page out to disk avoiding the fs deadlock. Writing them in
> shrink_mmap() would not fix the deadlock (obviously if shrink_mmap() is
> still recalled as now by try_to_free_pages() etc...).

You'd write them out only from a separate deamon that only needs to scan
the physical page map. That separate deamon might actually be kswapd, but
that's just an implementation detail rather than a conceptual issue.

Linus