Re: [RFC][PATCH 1/3] radix priority search tree - objrmap complexity fix

Hugh Dickins
2004-03-31T16:45:31Z

On Wed, 31 Mar 2004, Andrea Arcangeli wrote:
>
> So I rewritten the fix this way:
>
> + ret = add_to_swap_cache(page, entry);

I think you'll find that gets into trouble on the header page,
entry 0, which pmdisk/swsusp does access through this interface,
but swapping does not: I'd expect its swap_duplicate to fail.

I've put off dealing with this, wasn't a priority for me to
decide what to do with it. You might experiment with setting
p->swap_map[0] = 1 instead of SWAP_MAP_BAD in sys_swapon, but
offhand I'm unsure whether that's enough e.g. would the totals
come out right, would swapoff complete?

Just an idea, not something to finalize.

Hugh