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

[Pavel Machek <pavel@suse.cz>]

Hi!

> > An anonymous user page meets these requirements.  A did say "anal", but
> > rw_swap_page_sync() is a general-purpose library function and we shouldn't
> > be making assumptions about the type of page which the caller happens to be
> > feeding us.
> 
> that is a specialized backdoor to do I/O on _private_ pages, it's not a
> general-purpose library function for doing anonymous pages
> swapin/swapout, infact the only user is swap susped and we'd better
> forbid swap suspend to pass anonymous pages through that interface and
> be sure that nobody will ever attempt anything like that.
> 
> that interface is useful only to reach the swap device, for doing I/O on
> private pages outside the VM, in the old days that was used to
> read/write the swap header (again on a private page), swap suspend is
> using it for similar reasons on _private_ pages.

Ahha, so *here* is that discussion happening. I was only seeing it at
bugzilla, and could not make sense of it.

If swsusp/pmdisk are only user of rw_swap_page_sync, perhaps it should
be moved to power/ directory?
								Pavel
-- 
When do you have a heart between your knees?
[Johanka's followup: and *two* hearts?]