Re: [PATCH 09/11] lib/interval-tree: convert interval_tree to half closed intervals

[Davidlohr Bueso]

On Fri, 04 Oct 2019, Koenig, Christian wrote:

> Am 04.10.19 um 08:57 schrieb Christian König:
> > Am 03.10.19 um 22:18 schrieb Davidlohr Bueso:
> > > The generic tree tree really wants [a, b) intervals, not fully closed.
> > > As such convert it to use the new interval_tree_gen.h. Most of the
> > > conversions are straightforward, with the exception of perhaps
> > > radeon_vm_bo_set_addr(), but semantics have been tried to be left
> > > untouched.
> >
> > NAK, the whole thing won't work.
> >
> > See we need to handle the full device address space which means we
> > have values in the range of 0x0-0xffffffff.
> >
> > If you make this a closed interval then the end would wrap around to
> > 0x0 if long is only 32bit.
>
> Well I've just now re-read the subject line. From that it sounds like
> you are actually trying to fix the interval tree to use a half closed
> interval, e.g. something like [a, b[

Correct.

> But your code changes sometimes doesn't seem to reflect that.

Hmm the change simply aims at avoiding the end - 1 trick when dealing
with interval_tree insertions and lookups; the rest of the series
converts other interval tree users in a similar way, albeit some errors
which will be updated. What are your concerns about this patch?

Thanks,
Davidlohr