[Crash-utility] kernel 4.20-rc1 compatibility - radix tree replaced by xarray

[Dominique Martinet]

Hi,

just a head's up that the linux radix_tree got replaced by something
called xarray in 4.20 (already into master, will be in 4.20-rc1)

You can look at the patch series here:
https://lore.kernel.org/lkml/20180313132639.17387-3-willy@infradead.org/T/#m6a36aa7f22925c61ed59ed78312ccfadb08f9ecc

* [PATCH v9 11/61] xarray: Add definition of struct xarray
 -> replaces radix_tree_root by xarray
* [PATCH v9 12/61] xarray: Define struct xa_node
 -> replaces radix_tree_node by xa_node

As far as I can tell they look fairly close to radix_tree for now, but
while I hoped just renaming fields and removing max height might do the
trick, but it looks like one would need to actually look at the
differences in implementation as just doing that was a bit optimistic...
The tree iteration for running tasks got me 4 tasks so it obviously
didn't get very far; I probably missed something obvious.


For now I wanted to debug something else so went back a notch instead of
trying harder, I'll probably come back to this in the next few weeks if
nobody else has. Don't wait for me if you want to do it though :)

(hopefully that'll save someone a few minutes if they run into this
meanwhile)


Cheers,
-- 
Dominique Martinet | Asmadeus